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i2c: octeon: Split the driver into two parts
Move common functionality into a separate file in preparation of the re-use from the ThunderX i2c driver. Functions are slightly re-ordered but no other changes are included. Signed-off-by: Jan Glauber <jglauber@cavium.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Jan Glauber
Wolfram Sang
parent
68af512a74
commit
ad83665b46
@ -91,7 +91,8 @@ obj-$(CONFIG_I2C_UNIPHIER) += i2c-uniphier.o
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obj-$(CONFIG_I2C_UNIPHIER_F) += i2c-uniphier-f.o
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obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o
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obj-$(CONFIG_I2C_WMT) += i2c-wmt.o
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obj-$(CONFIG_I2C_OCTEON) += i2c-octeon-platdrv.o
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i2c-octeon-objs := i2c-octeon-core.o i2c-octeon-platdrv.o
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obj-$(CONFIG_I2C_OCTEON) += i2c-octeon.o
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obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o
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obj-$(CONFIG_I2C_XLR) += i2c-xlr.o
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obj-$(CONFIG_I2C_XLP9XX) += i2c-xlp9xx.o
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810
drivers/i2c/busses/i2c-octeon-core.c
Normal file
810
drivers/i2c/busses/i2c-octeon-core.c
Normal file
@ -0,0 +1,810 @@
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/*
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* (C) Copyright 2009-2010
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* Nokia Siemens Networks, michael.lawnick.ext@nsn.com
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*
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* Portions Copyright (C) 2010 - 2016 Cavium, Inc.
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*
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* This file contains the shared part of the driver for the i2c adapter in
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* Cavium Networks' OCTEON processors and ThunderX SOCs.
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*
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* This file is licensed under the terms of the GNU General Public
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* License version 2. This program is licensed "as is" without any
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* warranty of any kind, whether express or implied.
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*/
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#include <linux/delay.h>
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#include <linux/i2c.h>
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#include <linux/interrupt.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include "i2c-octeon-core.h"
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/* interrupt service routine */
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irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
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{
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struct octeon_i2c *i2c = dev_id;
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i2c->int_disable(i2c);
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wake_up(&i2c->queue);
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return IRQ_HANDLED;
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}
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static bool octeon_i2c_test_iflg(struct octeon_i2c *i2c)
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{
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return (octeon_i2c_ctl_read(i2c) & TWSI_CTL_IFLG);
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}
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static bool octeon_i2c_test_ready(struct octeon_i2c *i2c, bool *first)
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{
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if (octeon_i2c_test_iflg(i2c))
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return true;
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if (*first) {
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*first = false;
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return false;
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}
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/*
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* IRQ has signaled an event but IFLG hasn't changed.
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* Sleep and retry once.
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*/
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usleep_range(I2C_OCTEON_EVENT_WAIT, 2 * I2C_OCTEON_EVENT_WAIT);
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return octeon_i2c_test_iflg(i2c);
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}
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/**
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* octeon_i2c_wait - wait for the IFLG to be set
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* @i2c: The struct octeon_i2c
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*
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* Returns 0 on success, otherwise a negative errno.
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*/
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static int octeon_i2c_wait(struct octeon_i2c *i2c)
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{
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long time_left;
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bool first = 1;
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/*
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* Some chip revisions don't assert the irq in the interrupt
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* controller. So we must poll for the IFLG change.
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*/
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if (i2c->broken_irq_mode) {
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u64 end = get_jiffies_64() + i2c->adap.timeout;
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while (!octeon_i2c_test_iflg(i2c) &&
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time_before64(get_jiffies_64(), end))
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usleep_range(I2C_OCTEON_EVENT_WAIT / 2, I2C_OCTEON_EVENT_WAIT);
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return octeon_i2c_test_iflg(i2c) ? 0 : -ETIMEDOUT;
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}
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i2c->int_enable(i2c);
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time_left = wait_event_timeout(i2c->queue, octeon_i2c_test_ready(i2c, &first),
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i2c->adap.timeout);
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i2c->int_disable(i2c);
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if (i2c->broken_irq_check && !time_left &&
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octeon_i2c_test_iflg(i2c)) {
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dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n");
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i2c->broken_irq_mode = true;
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return 0;
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}
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if (!time_left)
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return -ETIMEDOUT;
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return 0;
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}
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static bool octeon_i2c_hlc_test_valid(struct octeon_i2c *i2c)
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{
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return (__raw_readq(i2c->twsi_base + SW_TWSI) & SW_TWSI_V) == 0;
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}
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static bool octeon_i2c_hlc_test_ready(struct octeon_i2c *i2c, bool *first)
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{
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/* check if valid bit is cleared */
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if (octeon_i2c_hlc_test_valid(i2c))
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return true;
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if (*first) {
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*first = false;
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return false;
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}
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/*
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* IRQ has signaled an event but valid bit isn't cleared.
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* Sleep and retry once.
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*/
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usleep_range(I2C_OCTEON_EVENT_WAIT, 2 * I2C_OCTEON_EVENT_WAIT);
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return octeon_i2c_hlc_test_valid(i2c);
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}
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static void octeon_i2c_hlc_int_clear(struct octeon_i2c *i2c)
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{
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/* clear ST/TS events, listen for neither */
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octeon_i2c_write_int(i2c, TWSI_INT_ST_INT | TWSI_INT_TS_INT);
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}
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/*
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* Cleanup low-level state & enable high-level controller.
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*/
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static void octeon_i2c_hlc_enable(struct octeon_i2c *i2c)
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{
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int try = 0;
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u64 val;
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if (i2c->hlc_enabled)
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return;
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i2c->hlc_enabled = true;
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while (1) {
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val = octeon_i2c_ctl_read(i2c);
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if (!(val & (TWSI_CTL_STA | TWSI_CTL_STP)))
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break;
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/* clear IFLG event */
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if (val & TWSI_CTL_IFLG)
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octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
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if (try++ > 100) {
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pr_err("%s: giving up\n", __func__);
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break;
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}
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/* spin until any start/stop has finished */
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udelay(10);
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}
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octeon_i2c_ctl_write(i2c, TWSI_CTL_CE | TWSI_CTL_AAK | TWSI_CTL_ENAB);
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}
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static void octeon_i2c_hlc_disable(struct octeon_i2c *i2c)
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{
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if (!i2c->hlc_enabled)
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return;
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i2c->hlc_enabled = false;
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octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
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}
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/**
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* octeon_i2c_hlc_wait - wait for an HLC operation to complete
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* @i2c: The struct octeon_i2c
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*
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* Returns 0 on success, otherwise -ETIMEDOUT.
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*/
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static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
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{
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bool first = 1;
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int time_left;
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/*
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* Some cn38xx boards don't assert the irq in the interrupt
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* controller. So we must poll for the valid bit change.
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*/
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if (i2c->broken_irq_mode) {
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u64 end = get_jiffies_64() + i2c->adap.timeout;
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while (!octeon_i2c_hlc_test_valid(i2c) &&
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time_before64(get_jiffies_64(), end))
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usleep_range(I2C_OCTEON_EVENT_WAIT / 2, I2C_OCTEON_EVENT_WAIT);
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return octeon_i2c_hlc_test_valid(i2c) ? 0 : -ETIMEDOUT;
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}
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i2c->hlc_int_enable(i2c);
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time_left = wait_event_timeout(i2c->queue,
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octeon_i2c_hlc_test_ready(i2c, &first),
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i2c->adap.timeout);
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i2c->hlc_int_disable(i2c);
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if (!time_left)
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octeon_i2c_hlc_int_clear(i2c);
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if (i2c->broken_irq_check && !time_left &&
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octeon_i2c_hlc_test_valid(i2c)) {
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dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n");
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i2c->broken_irq_mode = true;
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return 0;
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}
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if (!time_left)
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return -ETIMEDOUT;
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return 0;
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}
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static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read)
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{
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u8 stat = octeon_i2c_stat_read(i2c);
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switch (stat) {
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/* Everything is fine */
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case STAT_IDLE:
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case STAT_AD2W_ACK:
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case STAT_RXADDR_ACK:
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case STAT_TXADDR_ACK:
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case STAT_TXDATA_ACK:
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return 0;
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/* ACK allowed on pre-terminal bytes only */
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case STAT_RXDATA_ACK:
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if (!final_read)
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return 0;
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return -EIO;
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/* NAK allowed on terminal byte only */
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case STAT_RXDATA_NAK:
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if (final_read)
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return 0;
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return -EIO;
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/* Arbitration lost */
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case STAT_LOST_ARB_38:
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case STAT_LOST_ARB_68:
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case STAT_LOST_ARB_78:
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case STAT_LOST_ARB_B0:
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return -EAGAIN;
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/* Being addressed as slave, should back off & listen */
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case STAT_SLAVE_60:
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case STAT_SLAVE_70:
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case STAT_GENDATA_ACK:
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case STAT_GENDATA_NAK:
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return -EOPNOTSUPP;
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/* Core busy as slave */
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case STAT_SLAVE_80:
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case STAT_SLAVE_88:
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case STAT_SLAVE_A0:
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case STAT_SLAVE_A8:
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case STAT_SLAVE_LOST:
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case STAT_SLAVE_NAK:
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case STAT_SLAVE_ACK:
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return -EOPNOTSUPP;
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case STAT_TXDATA_NAK:
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return -EIO;
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case STAT_TXADDR_NAK:
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case STAT_RXADDR_NAK:
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case STAT_AD2W_NAK:
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return -ENXIO;
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default:
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dev_err(i2c->dev, "unhandled state: %d\n", stat);
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return -EIO;
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}
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}
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static int octeon_i2c_recovery(struct octeon_i2c *i2c)
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{
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int ret;
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ret = i2c_recover_bus(&i2c->adap);
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if (ret)
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/* recover failed, try hardware re-init */
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ret = octeon_i2c_init_lowlevel(i2c);
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return ret;
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}
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/**
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* octeon_i2c_start - send START to the bus
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* @i2c: The struct octeon_i2c
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*
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* Returns 0 on success, otherwise a negative errno.
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*/
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static int octeon_i2c_start(struct octeon_i2c *i2c)
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{
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int ret;
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u8 stat;
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octeon_i2c_hlc_disable(i2c);
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octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_STA);
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ret = octeon_i2c_wait(i2c);
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if (ret)
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goto error;
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stat = octeon_i2c_stat_read(i2c);
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if (stat == STAT_START || stat == STAT_REP_START)
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/* START successful, bail out */
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return 0;
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error:
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/* START failed, try to recover */
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ret = octeon_i2c_recovery(i2c);
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return (ret) ? ret : -EAGAIN;
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}
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/* send STOP to the bus */
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static void octeon_i2c_stop(struct octeon_i2c *i2c)
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{
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octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_STP);
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}
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/**
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* octeon_i2c_read - receive data from the bus via low-level controller
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* @i2c: The struct octeon_i2c
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* @target: Target address
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* @data: Pointer to the location to store the data
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* @rlength: Length of the data
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* @recv_len: flag for length byte
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*
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* The address is sent over the bus, then the data is read.
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*
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* Returns 0 on success, otherwise a negative errno.
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*/
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static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
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u8 *data, u16 *rlength, bool recv_len)
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{
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int i, result, length = *rlength;
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bool final_read = false;
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octeon_i2c_data_write(i2c, (target << 1) | 1);
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octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
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result = octeon_i2c_wait(i2c);
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if (result)
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return result;
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/* address OK ? */
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result = octeon_i2c_check_status(i2c, false);
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if (result)
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return result;
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for (i = 0; i < length; i++) {
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/*
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* For the last byte to receive TWSI_CTL_AAK must not be set.
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*
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* A special case is I2C_M_RECV_LEN where we don't know the
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* additional length yet. If recv_len is set we assume we're
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* not reading the final byte and therefore need to set
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* TWSI_CTL_AAK.
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*/
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if ((i + 1 == length) && !(recv_len && i == 0))
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final_read = true;
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/* clear iflg to allow next event */
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if (final_read)
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octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
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else
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octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_AAK);
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result = octeon_i2c_wait(i2c);
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if (result)
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return result;
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data[i] = octeon_i2c_data_read(i2c);
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if (recv_len && i == 0) {
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if (data[i] > I2C_SMBUS_BLOCK_MAX + 1)
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return -EPROTO;
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length += data[i];
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}
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result = octeon_i2c_check_status(i2c, final_read);
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if (result)
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return result;
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}
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*rlength = length;
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return 0;
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}
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/**
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* octeon_i2c_write - send data to the bus via low-level controller
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* @i2c: The struct octeon_i2c
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* @target: Target address
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* @data: Pointer to the data to be sent
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* @length: Length of the data
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*
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* The address is sent over the bus, then the data.
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*
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* Returns 0 on success, otherwise a negative errno.
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*/
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static int octeon_i2c_write(struct octeon_i2c *i2c, int target,
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const u8 *data, int length)
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{
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int i, result;
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octeon_i2c_data_write(i2c, target << 1);
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octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
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result = octeon_i2c_wait(i2c);
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if (result)
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return result;
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for (i = 0; i < length; i++) {
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result = octeon_i2c_check_status(i2c, false);
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if (result)
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return result;
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octeon_i2c_data_write(i2c, data[i]);
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octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
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result = octeon_i2c_wait(i2c);
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if (result)
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return result;
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}
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return 0;
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}
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/* high-level-controller pure read of up to 8 bytes */
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static int octeon_i2c_hlc_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
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{
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int i, j, ret = 0;
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u64 cmd;
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octeon_i2c_hlc_enable(i2c);
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octeon_i2c_hlc_int_clear(i2c);
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cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
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/* SIZE */
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cmd |= (u64)(msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
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/* A */
|
||||
cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
|
||||
|
||||
if (msgs[0].flags & I2C_M_TEN)
|
||||
cmd |= SW_TWSI_OP_10;
|
||||
else
|
||||
cmd |= SW_TWSI_OP_7;
|
||||
|
||||
octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI);
|
||||
ret = octeon_i2c_hlc_wait(i2c);
|
||||
if (ret)
|
||||
goto err;
|
||||
|
||||
cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
|
||||
if ((cmd & SW_TWSI_R) == 0)
|
||||
return -EAGAIN;
|
||||
|
||||
for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
|
||||
msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
|
||||
|
||||
if (msgs[0].len > 4) {
|
||||
cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
|
||||
for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
|
||||
msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
|
||||
}
|
||||
|
||||
err:
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* high-level-controller pure write of up to 8 bytes */
|
||||
static int octeon_i2c_hlc_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
|
||||
{
|
||||
int i, j, ret = 0;
|
||||
u64 cmd;
|
||||
|
||||
octeon_i2c_hlc_enable(i2c);
|
||||
octeon_i2c_hlc_int_clear(i2c);
|
||||
|
||||
cmd = SW_TWSI_V | SW_TWSI_SOVR;
|
||||
/* SIZE */
|
||||
cmd |= (u64)(msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
|
||||
/* A */
|
||||
cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
|
||||
|
||||
if (msgs[0].flags & I2C_M_TEN)
|
||||
cmd |= SW_TWSI_OP_10;
|
||||
else
|
||||
cmd |= SW_TWSI_OP_7;
|
||||
|
||||
for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
|
||||
cmd |= (u64)msgs[0].buf[j] << (8 * i);
|
||||
|
||||
if (msgs[0].len > 4) {
|
||||
u64 ext = 0;
|
||||
|
||||
for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
|
||||
ext |= (u64)msgs[0].buf[j] << (8 * i);
|
||||
octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT);
|
||||
}
|
||||
|
||||
octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI);
|
||||
ret = octeon_i2c_hlc_wait(i2c);
|
||||
if (ret)
|
||||
goto err;
|
||||
|
||||
cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
|
||||
if ((cmd & SW_TWSI_R) == 0)
|
||||
return -EAGAIN;
|
||||
|
||||
ret = octeon_i2c_check_status(i2c, false);
|
||||
|
||||
err:
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* high-level-controller composite write+read, msg0=addr, msg1=data */
|
||||
static int octeon_i2c_hlc_comp_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
|
||||
{
|
||||
int i, j, ret = 0;
|
||||
u64 cmd;
|
||||
|
||||
octeon_i2c_hlc_enable(i2c);
|
||||
|
||||
cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
|
||||
/* SIZE */
|
||||
cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
|
||||
/* A */
|
||||
cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
|
||||
|
||||
if (msgs[0].flags & I2C_M_TEN)
|
||||
cmd |= SW_TWSI_OP_10_IA;
|
||||
else
|
||||
cmd |= SW_TWSI_OP_7_IA;
|
||||
|
||||
if (msgs[0].len == 2) {
|
||||
u64 ext = 0;
|
||||
|
||||
cmd |= SW_TWSI_EIA;
|
||||
ext = (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
|
||||
cmd |= (u64)msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
|
||||
octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT);
|
||||
} else {
|
||||
cmd |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
|
||||
}
|
||||
|
||||
octeon_i2c_hlc_int_clear(i2c);
|
||||
octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI);
|
||||
|
||||
ret = octeon_i2c_hlc_wait(i2c);
|
||||
if (ret)
|
||||
goto err;
|
||||
|
||||
cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
|
||||
if ((cmd & SW_TWSI_R) == 0)
|
||||
return -EAGAIN;
|
||||
|
||||
for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
|
||||
msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
|
||||
|
||||
if (msgs[1].len > 4) {
|
||||
cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
|
||||
for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
|
||||
msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
|
||||
}
|
||||
|
||||
err:
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* high-level-controller composite write+write, m[0]len<=2, m[1]len<=8 */
|
||||
static int octeon_i2c_hlc_comp_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
|
||||
{
|
||||
bool set_ext = false;
|
||||
int i, j, ret = 0;
|
||||
u64 cmd, ext = 0;
|
||||
|
||||
octeon_i2c_hlc_enable(i2c);
|
||||
|
||||
cmd = SW_TWSI_V | SW_TWSI_SOVR;
|
||||
/* SIZE */
|
||||
cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
|
||||
/* A */
|
||||
cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
|
||||
|
||||
if (msgs[0].flags & I2C_M_TEN)
|
||||
cmd |= SW_TWSI_OP_10_IA;
|
||||
else
|
||||
cmd |= SW_TWSI_OP_7_IA;
|
||||
|
||||
if (msgs[0].len == 2) {
|
||||
cmd |= SW_TWSI_EIA;
|
||||
ext |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
|
||||
set_ext = true;
|
||||
cmd |= (u64)msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
|
||||
} else {
|
||||
cmd |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
|
||||
}
|
||||
|
||||
for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
|
||||
cmd |= (u64)msgs[1].buf[j] << (8 * i);
|
||||
|
||||
if (msgs[1].len > 4) {
|
||||
for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
|
||||
ext |= (u64)msgs[1].buf[j] << (8 * i);
|
||||
set_ext = true;
|
||||
}
|
||||
if (set_ext)
|
||||
octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT);
|
||||
|
||||
octeon_i2c_hlc_int_clear(i2c);
|
||||
octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI);
|
||||
|
||||
ret = octeon_i2c_hlc_wait(i2c);
|
||||
if (ret)
|
||||
goto err;
|
||||
|
||||
cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
|
||||
if ((cmd & SW_TWSI_R) == 0)
|
||||
return -EAGAIN;
|
||||
|
||||
ret = octeon_i2c_check_status(i2c, false);
|
||||
|
||||
err:
|
||||
return ret;
|
||||
}
|
||||
|
||||
/**
|
||||
* octeon_i2c_xfer - The driver's master_xfer function
|
||||
* @adap: Pointer to the i2c_adapter structure
|
||||
* @msgs: Pointer to the messages to be processed
|
||||
* @num: Length of the MSGS array
|
||||
*
|
||||
* Returns the number of messages processed, or a negative errno on failure.
|
||||
*/
|
||||
int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
|
||||
{
|
||||
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
||||
int i, ret = 0;
|
||||
|
||||
if (num == 1) {
|
||||
if (msgs[0].len > 0 && msgs[0].len <= 8) {
|
||||
if (msgs[0].flags & I2C_M_RD)
|
||||
ret = octeon_i2c_hlc_read(i2c, msgs);
|
||||
else
|
||||
ret = octeon_i2c_hlc_write(i2c, msgs);
|
||||
goto out;
|
||||
}
|
||||
} else if (num == 2) {
|
||||
if ((msgs[0].flags & I2C_M_RD) == 0 &&
|
||||
(msgs[1].flags & I2C_M_RECV_LEN) == 0 &&
|
||||
msgs[0].len > 0 && msgs[0].len <= 2 &&
|
||||
msgs[1].len > 0 && msgs[1].len <= 8 &&
|
||||
msgs[0].addr == msgs[1].addr) {
|
||||
if (msgs[1].flags & I2C_M_RD)
|
||||
ret = octeon_i2c_hlc_comp_read(i2c, msgs);
|
||||
else
|
||||
ret = octeon_i2c_hlc_comp_write(i2c, msgs);
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
|
||||
for (i = 0; ret == 0 && i < num; i++) {
|
||||
struct i2c_msg *pmsg = &msgs[i];
|
||||
|
||||
/* zero-length messages are not supported */
|
||||
if (!pmsg->len) {
|
||||
ret = -EOPNOTSUPP;
|
||||
break;
|
||||
}
|
||||
|
||||
ret = octeon_i2c_start(i2c);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
if (pmsg->flags & I2C_M_RD)
|
||||
ret = octeon_i2c_read(i2c, pmsg->addr, pmsg->buf,
|
||||
&pmsg->len, pmsg->flags & I2C_M_RECV_LEN);
|
||||
else
|
||||
ret = octeon_i2c_write(i2c, pmsg->addr, pmsg->buf,
|
||||
pmsg->len);
|
||||
}
|
||||
octeon_i2c_stop(i2c);
|
||||
out:
|
||||
return (ret != 0) ? ret : num;
|
||||
}
|
||||
|
||||
/* calculate and set clock divisors */
|
||||
void octeon_i2c_set_clock(struct octeon_i2c *i2c)
|
||||
{
|
||||
int tclk, thp_base, inc, thp_idx, mdiv_idx, ndiv_idx, foscl, diff;
|
||||
int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = 1000000;
|
||||
|
||||
for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
|
||||
/*
|
||||
* An mdiv value of less than 2 seems to not work well
|
||||
* with ds1337 RTCs, so we constrain it to larger values.
|
||||
*/
|
||||
for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
|
||||
/*
|
||||
* For given ndiv and mdiv values check the
|
||||
* two closest thp values.
|
||||
*/
|
||||
tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
|
||||
tclk *= (1 << ndiv_idx);
|
||||
thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
|
||||
|
||||
for (inc = 0; inc <= 1; inc++) {
|
||||
thp_idx = thp_base + inc;
|
||||
if (thp_idx < 5 || thp_idx > 0xff)
|
||||
continue;
|
||||
|
||||
foscl = i2c->sys_freq / (2 * (thp_idx + 1));
|
||||
foscl = foscl / (1 << ndiv_idx);
|
||||
foscl = foscl / (mdiv_idx + 1) / 10;
|
||||
diff = abs(foscl - i2c->twsi_freq);
|
||||
if (diff < delta_hz) {
|
||||
delta_hz = diff;
|
||||
thp = thp_idx;
|
||||
mdiv = mdiv_idx;
|
||||
ndiv = ndiv_idx;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
octeon_i2c_reg_write(i2c, SW_TWSI_OP_TWSI_CLK, thp);
|
||||
octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
|
||||
}
|
||||
|
||||
int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c)
|
||||
{
|
||||
u8 status = 0;
|
||||
int tries;
|
||||
|
||||
/* reset controller */
|
||||
octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_RST, 0);
|
||||
|
||||
for (tries = 10; tries && status != STAT_IDLE; tries--) {
|
||||
udelay(1);
|
||||
status = octeon_i2c_stat_read(i2c);
|
||||
if (status == STAT_IDLE)
|
||||
break;
|
||||
}
|
||||
|
||||
if (status != STAT_IDLE) {
|
||||
dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n",
|
||||
__func__, status);
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
/* toggle twice to force both teardowns */
|
||||
octeon_i2c_hlc_enable(i2c);
|
||||
octeon_i2c_hlc_disable(i2c);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int octeon_i2c_get_scl(struct i2c_adapter *adap)
|
||||
{
|
||||
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
||||
u64 state;
|
||||
|
||||
state = octeon_i2c_read_int(i2c);
|
||||
return state & TWSI_INT_SCL;
|
||||
}
|
||||
|
||||
static void octeon_i2c_set_scl(struct i2c_adapter *adap, int val)
|
||||
{
|
||||
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
||||
|
||||
octeon_i2c_write_int(i2c, TWSI_INT_SCL_OVR);
|
||||
}
|
||||
|
||||
static int octeon_i2c_get_sda(struct i2c_adapter *adap)
|
||||
{
|
||||
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
||||
u64 state;
|
||||
|
||||
state = octeon_i2c_read_int(i2c);
|
||||
return state & TWSI_INT_SDA;
|
||||
}
|
||||
|
||||
static void octeon_i2c_prepare_recovery(struct i2c_adapter *adap)
|
||||
{
|
||||
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
||||
|
||||
/*
|
||||
* The stop resets the state machine, does not _transmit_ STOP unless
|
||||
* engine was active.
|
||||
*/
|
||||
octeon_i2c_stop(i2c);
|
||||
|
||||
octeon_i2c_hlc_disable(i2c);
|
||||
octeon_i2c_write_int(i2c, 0);
|
||||
}
|
||||
|
||||
static void octeon_i2c_unprepare_recovery(struct i2c_adapter *adap)
|
||||
{
|
||||
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
||||
|
||||
octeon_i2c_write_int(i2c, 0);
|
||||
}
|
||||
|
||||
struct i2c_bus_recovery_info octeon_i2c_recovery_info = {
|
||||
.recover_bus = i2c_generic_scl_recovery,
|
||||
.get_scl = octeon_i2c_get_scl,
|
||||
.set_scl = octeon_i2c_set_scl,
|
||||
.get_sda = octeon_i2c_get_sda,
|
||||
.prepare_recovery = octeon_i2c_prepare_recovery,
|
||||
.unprepare_recovery = octeon_i2c_unprepare_recovery,
|
||||
};
|
||||
197
drivers/i2c/busses/i2c-octeon-core.h
Normal file
197
drivers/i2c/busses/i2c-octeon-core.h
Normal file
@ -0,0 +1,197 @@
|
||||
#include <linux/atomic.h>
|
||||
#include <linux/clk.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/device.h>
|
||||
#include <linux/i2c.h>
|
||||
#include <linux/io.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/pci.h>
|
||||
|
||||
/* Register offsets */
|
||||
#define SW_TWSI 0x00
|
||||
#define TWSI_INT 0x10
|
||||
#define SW_TWSI_EXT 0x18
|
||||
|
||||
/* Controller command patterns */
|
||||
#define SW_TWSI_V BIT_ULL(63) /* Valid bit */
|
||||
#define SW_TWSI_EIA BIT_ULL(61) /* Extended internal address */
|
||||
#define SW_TWSI_R BIT_ULL(56) /* Result or read bit */
|
||||
#define SW_TWSI_SOVR BIT_ULL(55) /* Size override */
|
||||
#define SW_TWSI_SIZE_SHIFT 52
|
||||
#define SW_TWSI_ADDR_SHIFT 40
|
||||
#define SW_TWSI_IA_SHIFT 32 /* Internal address */
|
||||
|
||||
/* Controller opcode word (bits 60:57) */
|
||||
#define SW_TWSI_OP_SHIFT 57
|
||||
#define SW_TWSI_OP_7 (0ULL << SW_TWSI_OP_SHIFT)
|
||||
#define SW_TWSI_OP_7_IA (1ULL << SW_TWSI_OP_SHIFT)
|
||||
#define SW_TWSI_OP_10 (2ULL << SW_TWSI_OP_SHIFT)
|
||||
#define SW_TWSI_OP_10_IA (3ULL << SW_TWSI_OP_SHIFT)
|
||||
#define SW_TWSI_OP_TWSI_CLK (4ULL << SW_TWSI_OP_SHIFT)
|
||||
#define SW_TWSI_OP_EOP (6ULL << SW_TWSI_OP_SHIFT) /* Extended opcode */
|
||||
|
||||
/* Controller extended opcode word (bits 34:32) */
|
||||
#define SW_TWSI_EOP_SHIFT 32
|
||||
#define SW_TWSI_EOP_TWSI_DATA (SW_TWSI_OP_EOP | 1ULL << SW_TWSI_EOP_SHIFT)
|
||||
#define SW_TWSI_EOP_TWSI_CTL (SW_TWSI_OP_EOP | 2ULL << SW_TWSI_EOP_SHIFT)
|
||||
#define SW_TWSI_EOP_TWSI_CLKCTL (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
|
||||
#define SW_TWSI_EOP_TWSI_STAT (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
|
||||
#define SW_TWSI_EOP_TWSI_RST (SW_TWSI_OP_EOP | 7ULL << SW_TWSI_EOP_SHIFT)
|
||||
|
||||
/* Controller command and status bits */
|
||||
#define TWSI_CTL_CE 0x80 /* High level controller enable */
|
||||
#define TWSI_CTL_ENAB 0x40 /* Bus enable */
|
||||
#define TWSI_CTL_STA 0x20 /* Master-mode start, HW clears when done */
|
||||
#define TWSI_CTL_STP 0x10 /* Master-mode stop, HW clears when done */
|
||||
#define TWSI_CTL_IFLG 0x08 /* HW event, SW writes 0 to ACK */
|
||||
#define TWSI_CTL_AAK 0x04 /* Assert ACK */
|
||||
|
||||
/* Status values */
|
||||
#define STAT_ERROR 0x00
|
||||
#define STAT_START 0x08
|
||||
#define STAT_REP_START 0x10
|
||||
#define STAT_TXADDR_ACK 0x18
|
||||
#define STAT_TXADDR_NAK 0x20
|
||||
#define STAT_TXDATA_ACK 0x28
|
||||
#define STAT_TXDATA_NAK 0x30
|
||||
#define STAT_LOST_ARB_38 0x38
|
||||
#define STAT_RXADDR_ACK 0x40
|
||||
#define STAT_RXADDR_NAK 0x48
|
||||
#define STAT_RXDATA_ACK 0x50
|
||||
#define STAT_RXDATA_NAK 0x58
|
||||
#define STAT_SLAVE_60 0x60
|
||||
#define STAT_LOST_ARB_68 0x68
|
||||
#define STAT_SLAVE_70 0x70
|
||||
#define STAT_LOST_ARB_78 0x78
|
||||
#define STAT_SLAVE_80 0x80
|
||||
#define STAT_SLAVE_88 0x88
|
||||
#define STAT_GENDATA_ACK 0x90
|
||||
#define STAT_GENDATA_NAK 0x98
|
||||
#define STAT_SLAVE_A0 0xA0
|
||||
#define STAT_SLAVE_A8 0xA8
|
||||
#define STAT_LOST_ARB_B0 0xB0
|
||||
#define STAT_SLAVE_LOST 0xB8
|
||||
#define STAT_SLAVE_NAK 0xC0
|
||||
#define STAT_SLAVE_ACK 0xC8
|
||||
#define STAT_AD2W_ACK 0xD0
|
||||
#define STAT_AD2W_NAK 0xD8
|
||||
#define STAT_IDLE 0xF8
|
||||
|
||||
/* TWSI_INT values */
|
||||
#define TWSI_INT_ST_INT BIT_ULL(0)
|
||||
#define TWSI_INT_TS_INT BIT_ULL(1)
|
||||
#define TWSI_INT_CORE_INT BIT_ULL(2)
|
||||
#define TWSI_INT_ST_EN BIT_ULL(4)
|
||||
#define TWSI_INT_TS_EN BIT_ULL(5)
|
||||
#define TWSI_INT_CORE_EN BIT_ULL(6)
|
||||
#define TWSI_INT_SDA_OVR BIT_ULL(8)
|
||||
#define TWSI_INT_SCL_OVR BIT_ULL(9)
|
||||
#define TWSI_INT_SDA BIT_ULL(10)
|
||||
#define TWSI_INT_SCL BIT_ULL(11)
|
||||
|
||||
#define I2C_OCTEON_EVENT_WAIT 80 /* microseconds */
|
||||
|
||||
struct octeon_i2c {
|
||||
wait_queue_head_t queue;
|
||||
struct i2c_adapter adap;
|
||||
int irq;
|
||||
int hlc_irq; /* For cn7890 only */
|
||||
u32 twsi_freq;
|
||||
int sys_freq;
|
||||
void __iomem *twsi_base;
|
||||
struct device *dev;
|
||||
bool hlc_enabled;
|
||||
bool broken_irq_mode;
|
||||
bool broken_irq_check;
|
||||
void (*int_enable)(struct octeon_i2c *);
|
||||
void (*int_disable)(struct octeon_i2c *);
|
||||
void (*hlc_int_enable)(struct octeon_i2c *);
|
||||
void (*hlc_int_disable)(struct octeon_i2c *);
|
||||
atomic_t int_enable_cnt;
|
||||
atomic_t hlc_int_enable_cnt;
|
||||
};
|
||||
|
||||
static inline void octeon_i2c_writeq_flush(u64 val, void __iomem *addr)
|
||||
{
|
||||
__raw_writeq(val, addr);
|
||||
__raw_readq(addr); /* wait for write to land */
|
||||
}
|
||||
|
||||
/**
|
||||
* octeon_i2c_reg_write - write an I2C core register
|
||||
* @i2c: The struct octeon_i2c
|
||||
* @eop_reg: Register selector
|
||||
* @data: Value to be written
|
||||
*
|
||||
* The I2C core registers are accessed indirectly via the SW_TWSI CSR.
|
||||
*/
|
||||
static inline void octeon_i2c_reg_write(struct octeon_i2c *i2c, u64 eop_reg, u8 data)
|
||||
{
|
||||
u64 tmp;
|
||||
|
||||
__raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + SW_TWSI);
|
||||
do {
|
||||
tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
|
||||
} while ((tmp & SW_TWSI_V) != 0);
|
||||
}
|
||||
|
||||
#define octeon_i2c_ctl_write(i2c, val) \
|
||||
octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_CTL, val)
|
||||
#define octeon_i2c_data_write(i2c, val) \
|
||||
octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_DATA, val)
|
||||
|
||||
/**
|
||||
* octeon_i2c_reg_read - read lower bits of an I2C core register
|
||||
* @i2c: The struct octeon_i2c
|
||||
* @eop_reg: Register selector
|
||||
*
|
||||
* Returns the data.
|
||||
*
|
||||
* The I2C core registers are accessed indirectly via the SW_TWSI CSR.
|
||||
*/
|
||||
static inline u8 octeon_i2c_reg_read(struct octeon_i2c *i2c, u64 eop_reg)
|
||||
{
|
||||
u64 tmp;
|
||||
|
||||
__raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base + SW_TWSI);
|
||||
do {
|
||||
tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
|
||||
} while ((tmp & SW_TWSI_V) != 0);
|
||||
|
||||
return tmp & 0xFF;
|
||||
}
|
||||
|
||||
#define octeon_i2c_ctl_read(i2c) \
|
||||
octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_CTL)
|
||||
#define octeon_i2c_data_read(i2c) \
|
||||
octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_DATA)
|
||||
#define octeon_i2c_stat_read(i2c) \
|
||||
octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_STAT)
|
||||
|
||||
/**
|
||||
* octeon_i2c_read_int - read the TWSI_INT register
|
||||
* @i2c: The struct octeon_i2c
|
||||
*
|
||||
* Returns the value of the register.
|
||||
*/
|
||||
static inline u64 octeon_i2c_read_int(struct octeon_i2c *i2c)
|
||||
{
|
||||
return __raw_readq(i2c->twsi_base + TWSI_INT);
|
||||
}
|
||||
|
||||
/**
|
||||
* octeon_i2c_write_int - write the TWSI_INT register
|
||||
* @i2c: The struct octeon_i2c
|
||||
* @data: Value to be written
|
||||
*/
|
||||
static inline void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
|
||||
{
|
||||
octeon_i2c_writeq_flush(data, i2c->twsi_base + TWSI_INT);
|
||||
}
|
||||
|
||||
/* Prototypes */
|
||||
irqreturn_t octeon_i2c_isr(int irq, void *dev_id);
|
||||
int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num);
|
||||
int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c);
|
||||
void octeon_i2c_set_clock(struct octeon_i2c *i2c);
|
||||
extern struct i2c_bus_recovery_info octeon_i2c_recovery_info;
|
||||
@ -24,191 +24,10 @@
|
||||
#include <linux/of.h>
|
||||
|
||||
#include <asm/octeon/octeon.h>
|
||||
#include "i2c-octeon-core.h"
|
||||
|
||||
#define DRV_NAME "i2c-octeon"
|
||||
|
||||
/* Register offsets */
|
||||
#define SW_TWSI 0x00
|
||||
#define TWSI_INT 0x10
|
||||
#define SW_TWSI_EXT 0x18
|
||||
|
||||
/* Controller command patterns */
|
||||
#define SW_TWSI_V BIT_ULL(63) /* Valid bit */
|
||||
#define SW_TWSI_EIA BIT_ULL(61) /* Extended internal address */
|
||||
#define SW_TWSI_R BIT_ULL(56) /* Result or read bit */
|
||||
#define SW_TWSI_SOVR BIT_ULL(55) /* Size override */
|
||||
#define SW_TWSI_SIZE_SHIFT 52
|
||||
#define SW_TWSI_ADDR_SHIFT 40
|
||||
#define SW_TWSI_IA_SHIFT 32 /* Internal address */
|
||||
|
||||
/* Controller opcode word (bits 60:57) */
|
||||
#define SW_TWSI_OP_SHIFT 57
|
||||
#define SW_TWSI_OP_7 (0ULL << SW_TWSI_OP_SHIFT)
|
||||
#define SW_TWSI_OP_7_IA (1ULL << SW_TWSI_OP_SHIFT)
|
||||
#define SW_TWSI_OP_10 (2ULL << SW_TWSI_OP_SHIFT)
|
||||
#define SW_TWSI_OP_10_IA (3ULL << SW_TWSI_OP_SHIFT)
|
||||
#define SW_TWSI_OP_TWSI_CLK (4ULL << SW_TWSI_OP_SHIFT)
|
||||
#define SW_TWSI_OP_EOP (6ULL << SW_TWSI_OP_SHIFT) /* Extended opcode */
|
||||
|
||||
/* Controller extended opcode word (bits 34:32) */
|
||||
#define SW_TWSI_EOP_SHIFT 32
|
||||
#define SW_TWSI_EOP_TWSI_DATA (SW_TWSI_OP_EOP | 1ULL << SW_TWSI_EOP_SHIFT)
|
||||
#define SW_TWSI_EOP_TWSI_CTL (SW_TWSI_OP_EOP | 2ULL << SW_TWSI_EOP_SHIFT)
|
||||
#define SW_TWSI_EOP_TWSI_CLKCTL (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
|
||||
#define SW_TWSI_EOP_TWSI_STAT (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
|
||||
#define SW_TWSI_EOP_TWSI_RST (SW_TWSI_OP_EOP | 7ULL << SW_TWSI_EOP_SHIFT)
|
||||
|
||||
/* Controller command and status bits */
|
||||
#define TWSI_CTL_CE 0x80 /* High level controller enable */
|
||||
#define TWSI_CTL_ENAB 0x40 /* Bus enable */
|
||||
#define TWSI_CTL_STA 0x20 /* Master-mode start, HW clears when done */
|
||||
#define TWSI_CTL_STP 0x10 /* Master-mode stop, HW clears when done */
|
||||
#define TWSI_CTL_IFLG 0x08 /* HW event, SW writes 0 to ACK */
|
||||
#define TWSI_CTL_AAK 0x04 /* Assert ACK */
|
||||
|
||||
/* Status values */
|
||||
#define STAT_ERROR 0x00
|
||||
#define STAT_START 0x08
|
||||
#define STAT_REP_START 0x10
|
||||
#define STAT_TXADDR_ACK 0x18
|
||||
#define STAT_TXADDR_NAK 0x20
|
||||
#define STAT_TXDATA_ACK 0x28
|
||||
#define STAT_TXDATA_NAK 0x30
|
||||
#define STAT_LOST_ARB_38 0x38
|
||||
#define STAT_RXADDR_ACK 0x40
|
||||
#define STAT_RXADDR_NAK 0x48
|
||||
#define STAT_RXDATA_ACK 0x50
|
||||
#define STAT_RXDATA_NAK 0x58
|
||||
#define STAT_SLAVE_60 0x60
|
||||
#define STAT_LOST_ARB_68 0x68
|
||||
#define STAT_SLAVE_70 0x70
|
||||
#define STAT_LOST_ARB_78 0x78
|
||||
#define STAT_SLAVE_80 0x80
|
||||
#define STAT_SLAVE_88 0x88
|
||||
#define STAT_GENDATA_ACK 0x90
|
||||
#define STAT_GENDATA_NAK 0x98
|
||||
#define STAT_SLAVE_A0 0xA0
|
||||
#define STAT_SLAVE_A8 0xA8
|
||||
#define STAT_LOST_ARB_B0 0xB0
|
||||
#define STAT_SLAVE_LOST 0xB8
|
||||
#define STAT_SLAVE_NAK 0xC0
|
||||
#define STAT_SLAVE_ACK 0xC8
|
||||
#define STAT_AD2W_ACK 0xD0
|
||||
#define STAT_AD2W_NAK 0xD8
|
||||
#define STAT_IDLE 0xF8
|
||||
|
||||
/* TWSI_INT values */
|
||||
#define TWSI_INT_ST_INT BIT_ULL(0)
|
||||
#define TWSI_INT_TS_INT BIT_ULL(1)
|
||||
#define TWSI_INT_CORE_INT BIT_ULL(2)
|
||||
#define TWSI_INT_ST_EN BIT_ULL(4)
|
||||
#define TWSI_INT_TS_EN BIT_ULL(5)
|
||||
#define TWSI_INT_CORE_EN BIT_ULL(6)
|
||||
#define TWSI_INT_SDA_OVR BIT_ULL(8)
|
||||
#define TWSI_INT_SCL_OVR BIT_ULL(9)
|
||||
#define TWSI_INT_SDA BIT_ULL(10)
|
||||
#define TWSI_INT_SCL BIT_ULL(11)
|
||||
|
||||
#define I2C_OCTEON_EVENT_WAIT 80 /* microseconds */
|
||||
|
||||
struct octeon_i2c {
|
||||
wait_queue_head_t queue;
|
||||
struct i2c_adapter adap;
|
||||
int irq;
|
||||
int hlc_irq; /* For cn7890 only */
|
||||
u32 twsi_freq;
|
||||
int sys_freq;
|
||||
void __iomem *twsi_base;
|
||||
struct device *dev;
|
||||
bool hlc_enabled;
|
||||
bool broken_irq_mode;
|
||||
bool broken_irq_check;
|
||||
void (*int_enable)(struct octeon_i2c *);
|
||||
void (*int_disable)(struct octeon_i2c *);
|
||||
void (*hlc_int_enable)(struct octeon_i2c *);
|
||||
void (*hlc_int_disable)(struct octeon_i2c *);
|
||||
atomic_t int_enable_cnt;
|
||||
atomic_t hlc_int_enable_cnt;
|
||||
};
|
||||
|
||||
static void octeon_i2c_writeq_flush(u64 val, void __iomem *addr)
|
||||
{
|
||||
__raw_writeq(val, addr);
|
||||
__raw_readq(addr); /* wait for write to land */
|
||||
}
|
||||
|
||||
/**
|
||||
* octeon_i2c_reg_write - write an I2C core register
|
||||
* @i2c: The struct octeon_i2c
|
||||
* @eop_reg: Register selector
|
||||
* @data: Value to be written
|
||||
*
|
||||
* The I2C core registers are accessed indirectly via the SW_TWSI CSR.
|
||||
*/
|
||||
static void octeon_i2c_reg_write(struct octeon_i2c *i2c, u64 eop_reg, u8 data)
|
||||
{
|
||||
u64 tmp;
|
||||
|
||||
__raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + SW_TWSI);
|
||||
do {
|
||||
tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
|
||||
} while ((tmp & SW_TWSI_V) != 0);
|
||||
}
|
||||
|
||||
#define octeon_i2c_ctl_write(i2c, val) \
|
||||
octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_CTL, val)
|
||||
#define octeon_i2c_data_write(i2c, val) \
|
||||
octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_DATA, val)
|
||||
|
||||
/**
|
||||
* octeon_i2c_reg_read - read lower bits of an I2C core register
|
||||
* @i2c: The struct octeon_i2c
|
||||
* @eop_reg: Register selector
|
||||
*
|
||||
* Returns the data.
|
||||
*
|
||||
* The I2C core registers are accessed indirectly via the SW_TWSI CSR.
|
||||
*/
|
||||
static u8 octeon_i2c_reg_read(struct octeon_i2c *i2c, u64 eop_reg)
|
||||
{
|
||||
u64 tmp;
|
||||
|
||||
__raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base + SW_TWSI);
|
||||
do {
|
||||
tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
|
||||
} while ((tmp & SW_TWSI_V) != 0);
|
||||
|
||||
return tmp & 0xFF;
|
||||
}
|
||||
|
||||
#define octeon_i2c_ctl_read(i2c) \
|
||||
octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_CTL)
|
||||
#define octeon_i2c_data_read(i2c) \
|
||||
octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_DATA)
|
||||
#define octeon_i2c_stat_read(i2c) \
|
||||
octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_STAT)
|
||||
|
||||
/**
|
||||
* octeon_i2c_read_int - read the TWSI_INT register
|
||||
* @i2c: The struct octeon_i2c
|
||||
*
|
||||
* Returns the value of the register.
|
||||
*/
|
||||
static u64 octeon_i2c_read_int(struct octeon_i2c *i2c)
|
||||
{
|
||||
return __raw_readq(i2c->twsi_base + TWSI_INT);
|
||||
}
|
||||
|
||||
/**
|
||||
* octeon_i2c_write_int - write the TWSI_INT register
|
||||
* @i2c: The struct octeon_i2c
|
||||
* @data: Value to be written
|
||||
*/
|
||||
static void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
|
||||
{
|
||||
octeon_i2c_writeq_flush(data, i2c->twsi_base + TWSI_INT);
|
||||
}
|
||||
|
||||
/**
|
||||
* octeon_i2c_int_enable - enable the CORE interrupt
|
||||
* @i2c: The struct octeon_i2c
|
||||
@ -280,58 +99,6 @@ static void octeon_i2c_hlc_int_disable78(struct octeon_i2c *i2c)
|
||||
__octeon_i2c_irq_disable(&i2c->hlc_int_enable_cnt, i2c->hlc_irq);
|
||||
}
|
||||
|
||||
/*
|
||||
* Cleanup low-level state & enable high-level controller.
|
||||
*/
|
||||
static void octeon_i2c_hlc_enable(struct octeon_i2c *i2c)
|
||||
{
|
||||
int try = 0;
|
||||
u64 val;
|
||||
|
||||
if (i2c->hlc_enabled)
|
||||
return;
|
||||
i2c->hlc_enabled = true;
|
||||
|
||||
while (1) {
|
||||
val = octeon_i2c_ctl_read(i2c);
|
||||
if (!(val & (TWSI_CTL_STA | TWSI_CTL_STP)))
|
||||
break;
|
||||
|
||||
/* clear IFLG event */
|
||||
if (val & TWSI_CTL_IFLG)
|
||||
octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
|
||||
|
||||
if (try++ > 100) {
|
||||
pr_err("%s: giving up\n", __func__);
|
||||
break;
|
||||
}
|
||||
|
||||
/* spin until any start/stop has finished */
|
||||
udelay(10);
|
||||
}
|
||||
octeon_i2c_ctl_write(i2c, TWSI_CTL_CE | TWSI_CTL_AAK | TWSI_CTL_ENAB);
|
||||
}
|
||||
|
||||
static void octeon_i2c_hlc_disable(struct octeon_i2c *i2c)
|
||||
{
|
||||
if (!i2c->hlc_enabled)
|
||||
return;
|
||||
|
||||
i2c->hlc_enabled = false;
|
||||
octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
|
||||
}
|
||||
|
||||
/* interrupt service routine */
|
||||
static irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
|
||||
{
|
||||
struct octeon_i2c *i2c = dev_id;
|
||||
|
||||
i2c->int_disable(i2c);
|
||||
wake_up(&i2c->queue);
|
||||
|
||||
return IRQ_HANDLED;
|
||||
}
|
||||
|
||||
/* HLC interrupt service routine */
|
||||
static irqreturn_t octeon_i2c_hlc_isr78(int irq, void *dev_id)
|
||||
{
|
||||
@ -343,749 +110,11 @@ static irqreturn_t octeon_i2c_hlc_isr78(int irq, void *dev_id)
|
||||
return IRQ_HANDLED;
|
||||
}
|
||||
|
||||
static bool octeon_i2c_test_iflg(struct octeon_i2c *i2c)
|
||||
{
|
||||
return (octeon_i2c_ctl_read(i2c) & TWSI_CTL_IFLG);
|
||||
}
|
||||
|
||||
static bool octeon_i2c_test_ready(struct octeon_i2c *i2c, bool *first)
|
||||
{
|
||||
if (octeon_i2c_test_iflg(i2c))
|
||||
return true;
|
||||
|
||||
if (*first) {
|
||||
*first = false;
|
||||
return false;
|
||||
}
|
||||
|
||||
/*
|
||||
* IRQ has signaled an event but IFLG hasn't changed.
|
||||
* Sleep and retry once.
|
||||
*/
|
||||
usleep_range(I2C_OCTEON_EVENT_WAIT, 2 * I2C_OCTEON_EVENT_WAIT);
|
||||
return octeon_i2c_test_iflg(i2c);
|
||||
}
|
||||
|
||||
/**
|
||||
* octeon_i2c_wait - wait for the IFLG to be set
|
||||
* @i2c: The struct octeon_i2c
|
||||
*
|
||||
* Returns 0 on success, otherwise a negative errno.
|
||||
*/
|
||||
static int octeon_i2c_wait(struct octeon_i2c *i2c)
|
||||
{
|
||||
long time_left;
|
||||
bool first = 1;
|
||||
|
||||
/*
|
||||
* Some chip revisions don't assert the irq in the interrupt
|
||||
* controller. So we must poll for the IFLG change.
|
||||
*/
|
||||
if (i2c->broken_irq_mode) {
|
||||
u64 end = get_jiffies_64() + i2c->adap.timeout;
|
||||
|
||||
while (!octeon_i2c_test_iflg(i2c) &&
|
||||
time_before64(get_jiffies_64(), end))
|
||||
usleep_range(I2C_OCTEON_EVENT_WAIT / 2, I2C_OCTEON_EVENT_WAIT);
|
||||
|
||||
return octeon_i2c_test_iflg(i2c) ? 0 : -ETIMEDOUT;
|
||||
}
|
||||
|
||||
i2c->int_enable(i2c);
|
||||
time_left = wait_event_timeout(i2c->queue, octeon_i2c_test_ready(i2c, &first),
|
||||
i2c->adap.timeout);
|
||||
i2c->int_disable(i2c);
|
||||
|
||||
if (i2c->broken_irq_check && !time_left &&
|
||||
octeon_i2c_test_iflg(i2c)) {
|
||||
dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n");
|
||||
i2c->broken_irq_mode = true;
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (!time_left)
|
||||
return -ETIMEDOUT;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read)
|
||||
{
|
||||
u8 stat = octeon_i2c_stat_read(i2c);
|
||||
|
||||
switch (stat) {
|
||||
/* Everything is fine */
|
||||
case STAT_IDLE:
|
||||
case STAT_AD2W_ACK:
|
||||
case STAT_RXADDR_ACK:
|
||||
case STAT_TXADDR_ACK:
|
||||
case STAT_TXDATA_ACK:
|
||||
return 0;
|
||||
|
||||
/* ACK allowed on pre-terminal bytes only */
|
||||
case STAT_RXDATA_ACK:
|
||||
if (!final_read)
|
||||
return 0;
|
||||
return -EIO;
|
||||
|
||||
/* NAK allowed on terminal byte only */
|
||||
case STAT_RXDATA_NAK:
|
||||
if (final_read)
|
||||
return 0;
|
||||
return -EIO;
|
||||
|
||||
/* Arbitration lost */
|
||||
case STAT_LOST_ARB_38:
|
||||
case STAT_LOST_ARB_68:
|
||||
case STAT_LOST_ARB_78:
|
||||
case STAT_LOST_ARB_B0:
|
||||
return -EAGAIN;
|
||||
|
||||
/* Being addressed as slave, should back off & listen */
|
||||
case STAT_SLAVE_60:
|
||||
case STAT_SLAVE_70:
|
||||
case STAT_GENDATA_ACK:
|
||||
case STAT_GENDATA_NAK:
|
||||
return -EOPNOTSUPP;
|
||||
|
||||
/* Core busy as slave */
|
||||
case STAT_SLAVE_80:
|
||||
case STAT_SLAVE_88:
|
||||
case STAT_SLAVE_A0:
|
||||
case STAT_SLAVE_A8:
|
||||
case STAT_SLAVE_LOST:
|
||||
case STAT_SLAVE_NAK:
|
||||
case STAT_SLAVE_ACK:
|
||||
return -EOPNOTSUPP;
|
||||
|
||||
case STAT_TXDATA_NAK:
|
||||
return -EIO;
|
||||
case STAT_TXADDR_NAK:
|
||||
case STAT_RXADDR_NAK:
|
||||
case STAT_AD2W_NAK:
|
||||
return -ENXIO;
|
||||
default:
|
||||
dev_err(i2c->dev, "unhandled state: %d\n", stat);
|
||||
return -EIO;
|
||||
}
|
||||
}
|
||||
|
||||
static bool octeon_i2c_hlc_test_valid(struct octeon_i2c *i2c)
|
||||
{
|
||||
return (__raw_readq(i2c->twsi_base + SW_TWSI) & SW_TWSI_V) == 0;
|
||||
}
|
||||
|
||||
static bool octeon_i2c_hlc_test_ready(struct octeon_i2c *i2c, bool *first)
|
||||
{
|
||||
/* check if valid bit is cleared */
|
||||
if (octeon_i2c_hlc_test_valid(i2c))
|
||||
return true;
|
||||
|
||||
if (*first) {
|
||||
*first = false;
|
||||
return false;
|
||||
}
|
||||
|
||||
/*
|
||||
* IRQ has signaled an event but valid bit isn't cleared.
|
||||
* Sleep and retry once.
|
||||
*/
|
||||
usleep_range(I2C_OCTEON_EVENT_WAIT, 2 * I2C_OCTEON_EVENT_WAIT);
|
||||
return octeon_i2c_hlc_test_valid(i2c);
|
||||
}
|
||||
|
||||
static void octeon_i2c_hlc_int_enable(struct octeon_i2c *i2c)
|
||||
{
|
||||
octeon_i2c_write_int(i2c, TWSI_INT_ST_EN);
|
||||
}
|
||||
|
||||
static void octeon_i2c_hlc_int_clear(struct octeon_i2c *i2c)
|
||||
{
|
||||
/* clear ST/TS events, listen for neither */
|
||||
octeon_i2c_write_int(i2c, TWSI_INT_ST_INT | TWSI_INT_TS_INT);
|
||||
}
|
||||
|
||||
/**
|
||||
* octeon_i2c_hlc_wait - wait for an HLC operation to complete
|
||||
* @i2c: The struct octeon_i2c
|
||||
*
|
||||
* Returns 0 on success, otherwise -ETIMEDOUT.
|
||||
*/
|
||||
static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
|
||||
{
|
||||
bool first = 1;
|
||||
int time_left;
|
||||
|
||||
/*
|
||||
* Some cn38xx boards don't assert the irq in the interrupt
|
||||
* controller. So we must poll for the valid bit change.
|
||||
*/
|
||||
if (i2c->broken_irq_mode) {
|
||||
u64 end = get_jiffies_64() + i2c->adap.timeout;
|
||||
|
||||
while (!octeon_i2c_hlc_test_valid(i2c) &&
|
||||
time_before64(get_jiffies_64(), end))
|
||||
usleep_range(I2C_OCTEON_EVENT_WAIT / 2, I2C_OCTEON_EVENT_WAIT);
|
||||
|
||||
return octeon_i2c_hlc_test_valid(i2c) ? 0 : -ETIMEDOUT;
|
||||
}
|
||||
|
||||
i2c->hlc_int_enable(i2c);
|
||||
time_left = wait_event_timeout(i2c->queue,
|
||||
octeon_i2c_hlc_test_ready(i2c, &first),
|
||||
i2c->adap.timeout);
|
||||
i2c->hlc_int_disable(i2c);
|
||||
if (!time_left)
|
||||
octeon_i2c_hlc_int_clear(i2c);
|
||||
|
||||
if (i2c->broken_irq_check && !time_left &&
|
||||
octeon_i2c_hlc_test_valid(i2c)) {
|
||||
dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n");
|
||||
i2c->broken_irq_mode = true;
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (!time_left)
|
||||
return -ETIMEDOUT;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* high-level-controller pure read of up to 8 bytes */
|
||||
static int octeon_i2c_hlc_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
|
||||
{
|
||||
int i, j, ret = 0;
|
||||
u64 cmd;
|
||||
|
||||
octeon_i2c_hlc_enable(i2c);
|
||||
octeon_i2c_hlc_int_clear(i2c);
|
||||
|
||||
cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
|
||||
/* SIZE */
|
||||
cmd |= (u64)(msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
|
||||
/* A */
|
||||
cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
|
||||
|
||||
if (msgs[0].flags & I2C_M_TEN)
|
||||
cmd |= SW_TWSI_OP_10;
|
||||
else
|
||||
cmd |= SW_TWSI_OP_7;
|
||||
|
||||
octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI);
|
||||
ret = octeon_i2c_hlc_wait(i2c);
|
||||
if (ret)
|
||||
goto err;
|
||||
|
||||
cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
|
||||
if ((cmd & SW_TWSI_R) == 0)
|
||||
return -EAGAIN;
|
||||
|
||||
for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
|
||||
msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
|
||||
|
||||
if (msgs[0].len > 4) {
|
||||
cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
|
||||
for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
|
||||
msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
|
||||
}
|
||||
|
||||
err:
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* high-level-controller pure write of up to 8 bytes */
|
||||
static int octeon_i2c_hlc_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
|
||||
{
|
||||
int i, j, ret = 0;
|
||||
u64 cmd;
|
||||
|
||||
octeon_i2c_hlc_enable(i2c);
|
||||
octeon_i2c_hlc_int_clear(i2c);
|
||||
|
||||
cmd = SW_TWSI_V | SW_TWSI_SOVR;
|
||||
/* SIZE */
|
||||
cmd |= (u64)(msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
|
||||
/* A */
|
||||
cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
|
||||
|
||||
if (msgs[0].flags & I2C_M_TEN)
|
||||
cmd |= SW_TWSI_OP_10;
|
||||
else
|
||||
cmd |= SW_TWSI_OP_7;
|
||||
|
||||
for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
|
||||
cmd |= (u64)msgs[0].buf[j] << (8 * i);
|
||||
|
||||
if (msgs[0].len > 4) {
|
||||
u64 ext = 0;
|
||||
|
||||
for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
|
||||
ext |= (u64)msgs[0].buf[j] << (8 * i);
|
||||
octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT);
|
||||
}
|
||||
|
||||
octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI);
|
||||
ret = octeon_i2c_hlc_wait(i2c);
|
||||
if (ret)
|
||||
goto err;
|
||||
|
||||
cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
|
||||
if ((cmd & SW_TWSI_R) == 0)
|
||||
return -EAGAIN;
|
||||
|
||||
ret = octeon_i2c_check_status(i2c, false);
|
||||
|
||||
err:
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* high-level-controller composite write+read, msg0=addr, msg1=data */
|
||||
static int octeon_i2c_hlc_comp_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
|
||||
{
|
||||
int i, j, ret = 0;
|
||||
u64 cmd;
|
||||
|
||||
octeon_i2c_hlc_enable(i2c);
|
||||
|
||||
cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
|
||||
/* SIZE */
|
||||
cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
|
||||
/* A */
|
||||
cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
|
||||
|
||||
if (msgs[0].flags & I2C_M_TEN)
|
||||
cmd |= SW_TWSI_OP_10_IA;
|
||||
else
|
||||
cmd |= SW_TWSI_OP_7_IA;
|
||||
|
||||
if (msgs[0].len == 2) {
|
||||
u64 ext = 0;
|
||||
|
||||
cmd |= SW_TWSI_EIA;
|
||||
ext = (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
|
||||
cmd |= (u64)msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
|
||||
octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT);
|
||||
} else {
|
||||
cmd |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
|
||||
}
|
||||
|
||||
octeon_i2c_hlc_int_clear(i2c);
|
||||
octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI);
|
||||
|
||||
ret = octeon_i2c_hlc_wait(i2c);
|
||||
if (ret)
|
||||
goto err;
|
||||
|
||||
cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
|
||||
if ((cmd & SW_TWSI_R) == 0)
|
||||
return -EAGAIN;
|
||||
|
||||
for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
|
||||
msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
|
||||
|
||||
if (msgs[1].len > 4) {
|
||||
cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
|
||||
for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
|
||||
msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
|
||||
}
|
||||
|
||||
err:
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* high-level-controller composite write+write, m[0]len<=2, m[1]len<=8 */
|
||||
static int octeon_i2c_hlc_comp_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
|
||||
{
|
||||
bool set_ext = false;
|
||||
int i, j, ret = 0;
|
||||
u64 cmd, ext = 0;
|
||||
|
||||
octeon_i2c_hlc_enable(i2c);
|
||||
|
||||
cmd = SW_TWSI_V | SW_TWSI_SOVR;
|
||||
/* SIZE */
|
||||
cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
|
||||
/* A */
|
||||
cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
|
||||
|
||||
if (msgs[0].flags & I2C_M_TEN)
|
||||
cmd |= SW_TWSI_OP_10_IA;
|
||||
else
|
||||
cmd |= SW_TWSI_OP_7_IA;
|
||||
|
||||
if (msgs[0].len == 2) {
|
||||
cmd |= SW_TWSI_EIA;
|
||||
ext |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
|
||||
set_ext = true;
|
||||
cmd |= (u64)msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
|
||||
} else {
|
||||
cmd |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
|
||||
}
|
||||
|
||||
for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
|
||||
cmd |= (u64)msgs[1].buf[j] << (8 * i);
|
||||
|
||||
if (msgs[1].len > 4) {
|
||||
for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
|
||||
ext |= (u64)msgs[1].buf[j] << (8 * i);
|
||||
set_ext = true;
|
||||
}
|
||||
if (set_ext)
|
||||
octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT);
|
||||
|
||||
octeon_i2c_hlc_int_clear(i2c);
|
||||
octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI);
|
||||
|
||||
ret = octeon_i2c_hlc_wait(i2c);
|
||||
if (ret)
|
||||
goto err;
|
||||
|
||||
cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
|
||||
if ((cmd & SW_TWSI_R) == 0)
|
||||
return -EAGAIN;
|
||||
|
||||
ret = octeon_i2c_check_status(i2c, false);
|
||||
|
||||
err:
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* calculate and set clock divisors */
|
||||
static void octeon_i2c_set_clock(struct octeon_i2c *i2c)
|
||||
{
|
||||
int tclk, thp_base, inc, thp_idx, mdiv_idx, ndiv_idx, foscl, diff;
|
||||
int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = 1000000;
|
||||
|
||||
for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
|
||||
/*
|
||||
* An mdiv value of less than 2 seems to not work well
|
||||
* with ds1337 RTCs, so we constrain it to larger values.
|
||||
*/
|
||||
for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
|
||||
/*
|
||||
* For given ndiv and mdiv values check the
|
||||
* two closest thp values.
|
||||
*/
|
||||
tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
|
||||
tclk *= (1 << ndiv_idx);
|
||||
thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
|
||||
|
||||
for (inc = 0; inc <= 1; inc++) {
|
||||
thp_idx = thp_base + inc;
|
||||
if (thp_idx < 5 || thp_idx > 0xff)
|
||||
continue;
|
||||
|
||||
foscl = i2c->sys_freq / (2 * (thp_idx + 1));
|
||||
foscl = foscl / (1 << ndiv_idx);
|
||||
foscl = foscl / (mdiv_idx + 1) / 10;
|
||||
diff = abs(foscl - i2c->twsi_freq);
|
||||
if (diff < delta_hz) {
|
||||
delta_hz = diff;
|
||||
thp = thp_idx;
|
||||
mdiv = mdiv_idx;
|
||||
ndiv = ndiv_idx;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
octeon_i2c_reg_write(i2c, SW_TWSI_OP_TWSI_CLK, thp);
|
||||
octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
|
||||
}
|
||||
|
||||
static int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c)
|
||||
{
|
||||
u8 status = 0;
|
||||
int tries;
|
||||
|
||||
/* reset controller */
|
||||
octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_RST, 0);
|
||||
|
||||
for (tries = 10; tries && status != STAT_IDLE; tries--) {
|
||||
udelay(1);
|
||||
status = octeon_i2c_stat_read(i2c);
|
||||
if (status == STAT_IDLE)
|
||||
break;
|
||||
}
|
||||
|
||||
if (status != STAT_IDLE) {
|
||||
dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n",
|
||||
__func__, status);
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
/* toggle twice to force both teardowns */
|
||||
octeon_i2c_hlc_enable(i2c);
|
||||
octeon_i2c_hlc_disable(i2c);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int octeon_i2c_recovery(struct octeon_i2c *i2c)
|
||||
{
|
||||
int ret;
|
||||
|
||||
ret = i2c_recover_bus(&i2c->adap);
|
||||
if (ret)
|
||||
/* recover failed, try hardware re-init */
|
||||
ret = octeon_i2c_init_lowlevel(i2c);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/**
|
||||
* octeon_i2c_start - send START to the bus
|
||||
* @i2c: The struct octeon_i2c
|
||||
*
|
||||
* Returns 0 on success, otherwise a negative errno.
|
||||
*/
|
||||
static int octeon_i2c_start(struct octeon_i2c *i2c)
|
||||
{
|
||||
int ret;
|
||||
u8 stat;
|
||||
|
||||
octeon_i2c_hlc_disable(i2c);
|
||||
|
||||
octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_STA);
|
||||
ret = octeon_i2c_wait(i2c);
|
||||
if (ret)
|
||||
goto error;
|
||||
|
||||
stat = octeon_i2c_stat_read(i2c);
|
||||
if (stat == STAT_START || stat == STAT_REP_START)
|
||||
/* START successful, bail out */
|
||||
return 0;
|
||||
|
||||
error:
|
||||
/* START failed, try to recover */
|
||||
ret = octeon_i2c_recovery(i2c);
|
||||
return (ret) ? ret : -EAGAIN;
|
||||
}
|
||||
|
||||
/* send STOP to the bus */
|
||||
static void octeon_i2c_stop(struct octeon_i2c *i2c)
|
||||
{
|
||||
octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_STP);
|
||||
}
|
||||
|
||||
/**
|
||||
* octeon_i2c_write - send data to the bus via low-level controller
|
||||
* @i2c: The struct octeon_i2c
|
||||
* @target: Target address
|
||||
* @data: Pointer to the data to be sent
|
||||
* @length: Length of the data
|
||||
*
|
||||
* The address is sent over the bus, then the data.
|
||||
*
|
||||
* Returns 0 on success, otherwise a negative errno.
|
||||
*/
|
||||
static int octeon_i2c_write(struct octeon_i2c *i2c, int target,
|
||||
const u8 *data, int length)
|
||||
{
|
||||
int i, result;
|
||||
|
||||
octeon_i2c_data_write(i2c, target << 1);
|
||||
octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
|
||||
|
||||
result = octeon_i2c_wait(i2c);
|
||||
if (result)
|
||||
return result;
|
||||
|
||||
for (i = 0; i < length; i++) {
|
||||
result = octeon_i2c_check_status(i2c, false);
|
||||
if (result)
|
||||
return result;
|
||||
|
||||
octeon_i2c_data_write(i2c, data[i]);
|
||||
octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
|
||||
|
||||
result = octeon_i2c_wait(i2c);
|
||||
if (result)
|
||||
return result;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* octeon_i2c_read - receive data from the bus via low-level controller
|
||||
* @i2c: The struct octeon_i2c
|
||||
* @target: Target address
|
||||
* @data: Pointer to the location to store the data
|
||||
* @rlength: Length of the data
|
||||
* @recv_len: flag for length byte
|
||||
*
|
||||
* The address is sent over the bus, then the data is read.
|
||||
*
|
||||
* Returns 0 on success, otherwise a negative errno.
|
||||
*/
|
||||
static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
|
||||
u8 *data, u16 *rlength, bool recv_len)
|
||||
{
|
||||
int i, result, length = *rlength;
|
||||
bool final_read = false;
|
||||
|
||||
octeon_i2c_data_write(i2c, (target << 1) | 1);
|
||||
octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
|
||||
|
||||
result = octeon_i2c_wait(i2c);
|
||||
if (result)
|
||||
return result;
|
||||
|
||||
/* address OK ? */
|
||||
result = octeon_i2c_check_status(i2c, false);
|
||||
if (result)
|
||||
return result;
|
||||
|
||||
for (i = 0; i < length; i++) {
|
||||
/*
|
||||
* For the last byte to receive TWSI_CTL_AAK must not be set.
|
||||
*
|
||||
* A special case is I2C_M_RECV_LEN where we don't know the
|
||||
* additional length yet. If recv_len is set we assume we're
|
||||
* not reading the final byte and therefore need to set
|
||||
* TWSI_CTL_AAK.
|
||||
*/
|
||||
if ((i + 1 == length) && !(recv_len && i == 0))
|
||||
final_read = true;
|
||||
|
||||
/* clear iflg to allow next event */
|
||||
if (final_read)
|
||||
octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
|
||||
else
|
||||
octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_AAK);
|
||||
|
||||
result = octeon_i2c_wait(i2c);
|
||||
if (result)
|
||||
return result;
|
||||
|
||||
data[i] = octeon_i2c_data_read(i2c);
|
||||
if (recv_len && i == 0) {
|
||||
if (data[i] > I2C_SMBUS_BLOCK_MAX + 1)
|
||||
return -EPROTO;
|
||||
length += data[i];
|
||||
}
|
||||
|
||||
result = octeon_i2c_check_status(i2c, final_read);
|
||||
if (result)
|
||||
return result;
|
||||
}
|
||||
*rlength = length;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* octeon_i2c_xfer - The driver's master_xfer function
|
||||
* @adap: Pointer to the i2c_adapter structure
|
||||
* @msgs: Pointer to the messages to be processed
|
||||
* @num: Length of the MSGS array
|
||||
*
|
||||
* Returns the number of messages processed, or a negative errno on failure.
|
||||
*/
|
||||
static int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
|
||||
int num)
|
||||
{
|
||||
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
||||
int i, ret = 0;
|
||||
|
||||
if (num == 1) {
|
||||
if (msgs[0].len > 0 && msgs[0].len <= 8) {
|
||||
if (msgs[0].flags & I2C_M_RD)
|
||||
ret = octeon_i2c_hlc_read(i2c, msgs);
|
||||
else
|
||||
ret = octeon_i2c_hlc_write(i2c, msgs);
|
||||
goto out;
|
||||
}
|
||||
} else if (num == 2) {
|
||||
if ((msgs[0].flags & I2C_M_RD) == 0 &&
|
||||
(msgs[1].flags & I2C_M_RECV_LEN) == 0 &&
|
||||
msgs[0].len > 0 && msgs[0].len <= 2 &&
|
||||
msgs[1].len > 0 && msgs[1].len <= 8 &&
|
||||
msgs[0].addr == msgs[1].addr) {
|
||||
if (msgs[1].flags & I2C_M_RD)
|
||||
ret = octeon_i2c_hlc_comp_read(i2c, msgs);
|
||||
else
|
||||
ret = octeon_i2c_hlc_comp_write(i2c, msgs);
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
|
||||
for (i = 0; ret == 0 && i < num; i++) {
|
||||
struct i2c_msg *pmsg = &msgs[i];
|
||||
|
||||
/* zero-length messages are not supported */
|
||||
if (!pmsg->len) {
|
||||
ret = -EOPNOTSUPP;
|
||||
break;
|
||||
}
|
||||
|
||||
ret = octeon_i2c_start(i2c);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
if (pmsg->flags & I2C_M_RD)
|
||||
ret = octeon_i2c_read(i2c, pmsg->addr, pmsg->buf,
|
||||
&pmsg->len, pmsg->flags & I2C_M_RECV_LEN);
|
||||
else
|
||||
ret = octeon_i2c_write(i2c, pmsg->addr, pmsg->buf,
|
||||
pmsg->len);
|
||||
}
|
||||
octeon_i2c_stop(i2c);
|
||||
out:
|
||||
return (ret != 0) ? ret : num;
|
||||
}
|
||||
|
||||
static int octeon_i2c_get_scl(struct i2c_adapter *adap)
|
||||
{
|
||||
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
||||
u64 state;
|
||||
|
||||
state = octeon_i2c_read_int(i2c);
|
||||
return state & TWSI_INT_SCL;
|
||||
}
|
||||
|
||||
static void octeon_i2c_set_scl(struct i2c_adapter *adap, int val)
|
||||
{
|
||||
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
||||
|
||||
octeon_i2c_write_int(i2c, TWSI_INT_SCL_OVR);
|
||||
}
|
||||
|
||||
static int octeon_i2c_get_sda(struct i2c_adapter *adap)
|
||||
{
|
||||
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
||||
u64 state;
|
||||
|
||||
state = octeon_i2c_read_int(i2c);
|
||||
return state & TWSI_INT_SDA;
|
||||
}
|
||||
|
||||
static void octeon_i2c_prepare_recovery(struct i2c_adapter *adap)
|
||||
{
|
||||
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
||||
|
||||
/*
|
||||
* The stop resets the state machine, does not _transmit_ STOP unless
|
||||
* engine was active.
|
||||
*/
|
||||
octeon_i2c_stop(i2c);
|
||||
|
||||
octeon_i2c_hlc_disable(i2c);
|
||||
octeon_i2c_write_int(i2c, 0);
|
||||
}
|
||||
|
||||
static void octeon_i2c_unprepare_recovery(struct i2c_adapter *adap)
|
||||
{
|
||||
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
|
||||
|
||||
octeon_i2c_write_int(i2c, 0);
|
||||
}
|
||||
|
||||
static struct i2c_bus_recovery_info octeon_i2c_recovery_info = {
|
||||
.recover_bus = i2c_generic_scl_recovery,
|
||||
.get_scl = octeon_i2c_get_scl,
|
||||
.set_scl = octeon_i2c_set_scl,
|
||||
.get_sda = octeon_i2c_get_sda,
|
||||
.prepare_recovery = octeon_i2c_prepare_recovery,
|
||||
.unprepare_recovery = octeon_i2c_unprepare_recovery,
|
||||
};
|
||||
|
||||
static u32 octeon_i2c_functionality(struct i2c_adapter *adap)
|
||||
{
|
||||
return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
|
||||
|
||||
Loading…
Reference in New Issue
Block a user