korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-14 06:24:53 +08:00
Code Issues Packages Projects Releases Wiki Activity
e6aa640eb2
linux/drivers/i2c/busses/i2c-jz4780.c
Thomas Gleixner c942fddf87 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 
Based on 3 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [kishon] [vijay] [abraham]
  [i] [kishon]@[ti] [com] this program is distributed in the hope that
  it will be useful but without any warranty without even the implied
  warranty of merchantability or fitness for a particular purpose see
  the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [graeme] [gregory]
  [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
  [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
  [hk] [hemahk]@[ti] [com] this program is distributed in the hope
  that it will be useful but without any warranty without even the
  implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:37 -07:00

826 lines
20 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Ingenic JZ4780 I2C bus driver
*
* Copyright (C) 2006 - 2009 Ingenic Semiconductor Inc.
* Copyright (C) 2015 Imagination Technologies
*/
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/time.h>
#define JZ4780_I2C_CTRL 0x00
#define JZ4780_I2C_TAR 0x04
#define JZ4780_I2C_SAR 0x08
#define JZ4780_I2C_DC 0x10
#define JZ4780_I2C_SHCNT 0x14
#define JZ4780_I2C_SLCNT 0x18
#define JZ4780_I2C_FHCNT 0x1C
#define JZ4780_I2C_FLCNT 0x20
#define JZ4780_I2C_INTST 0x2C
#define JZ4780_I2C_INTM 0x30
#define JZ4780_I2C_RXTL 0x38
#define JZ4780_I2C_TXTL 0x3C
#define JZ4780_I2C_CINTR 0x40
#define JZ4780_I2C_CRXUF 0x44
#define JZ4780_I2C_CRXOF 0x48
#define JZ4780_I2C_CTXOF 0x4C
#define JZ4780_I2C_CRXREQ 0x50
#define JZ4780_I2C_CTXABRT 0x54
#define JZ4780_I2C_CRXDONE 0x58
#define JZ4780_I2C_CACT 0x5C
#define JZ4780_I2C_CSTP 0x60
#define JZ4780_I2C_CSTT 0x64
#define JZ4780_I2C_CGC 0x68
#define JZ4780_I2C_ENB 0x6C
#define JZ4780_I2C_STA 0x70
#define JZ4780_I2C_TXABRT 0x80
#define JZ4780_I2C_DMACR 0x88
#define JZ4780_I2C_DMATDLR 0x8C
#define JZ4780_I2C_DMARDLR 0x90
#define JZ4780_I2C_SDASU 0x94
#define JZ4780_I2C_ACKGC 0x98
#define JZ4780_I2C_ENSTA 0x9C
#define JZ4780_I2C_SDAHD 0xD0
#define JZ4780_I2C_CTRL_STPHLD BIT(7)
#define JZ4780_I2C_CTRL_SLVDIS BIT(6)
#define JZ4780_I2C_CTRL_REST BIT(5)
#define JZ4780_I2C_CTRL_MATP BIT(4)
#define JZ4780_I2C_CTRL_SATP BIT(3)
#define JZ4780_I2C_CTRL_SPDF BIT(2)
#define JZ4780_I2C_CTRL_SPDS BIT(1)
#define JZ4780_I2C_CTRL_MD BIT(0)
#define JZ4780_I2C_STA_SLVACT BIT(6)
#define JZ4780_I2C_STA_MSTACT BIT(5)
#define JZ4780_I2C_STA_RFF BIT(4)
#define JZ4780_I2C_STA_RFNE BIT(3)
#define JZ4780_I2C_STA_TFE BIT(2)
#define JZ4780_I2C_STA_TFNF BIT(1)
#define JZ4780_I2C_STA_ACT BIT(0)
static const char * const jz4780_i2c_abrt_src[] = {
"ABRT_7B_ADDR_NOACK",
"ABRT_10ADDR1_NOACK",
"ABRT_10ADDR2_NOACK",
"ABRT_XDATA_NOACK",
"ABRT_GCALL_NOACK",
"ABRT_GCALL_READ",
"ABRT_HS_ACKD",
"SBYTE_ACKDET",
"ABRT_HS_NORSTRT",
"SBYTE_NORSTRT",
"ABRT_10B_RD_NORSTRT",
"ABRT_MASTER_DIS",
"ARB_LOST",
"SLVFLUSH_TXFIFO",
"SLV_ARBLOST",
"SLVRD_INTX",
};
#define JZ4780_I2C_INTST_IGC BIT(11)
#define JZ4780_I2C_INTST_ISTT BIT(10)
#define JZ4780_I2C_INTST_ISTP BIT(9)
#define JZ4780_I2C_INTST_IACT BIT(8)
#define JZ4780_I2C_INTST_RXDN BIT(7)
#define JZ4780_I2C_INTST_TXABT BIT(6)
#define JZ4780_I2C_INTST_RDREQ BIT(5)
#define JZ4780_I2C_INTST_TXEMP BIT(4)
#define JZ4780_I2C_INTST_TXOF BIT(3)
#define JZ4780_I2C_INTST_RXFL BIT(2)
#define JZ4780_I2C_INTST_RXOF BIT(1)
#define JZ4780_I2C_INTST_RXUF BIT(0)
#define JZ4780_I2C_INTM_MIGC BIT(11)
#define JZ4780_I2C_INTM_MISTT BIT(10)
#define JZ4780_I2C_INTM_MISTP BIT(9)
#define JZ4780_I2C_INTM_MIACT BIT(8)
#define JZ4780_I2C_INTM_MRXDN BIT(7)
#define JZ4780_I2C_INTM_MTXABT BIT(6)
#define JZ4780_I2C_INTM_MRDREQ BIT(5)
#define JZ4780_I2C_INTM_MTXEMP BIT(4)
#define JZ4780_I2C_INTM_MTXOF BIT(3)
#define JZ4780_I2C_INTM_MRXFL BIT(2)
#define JZ4780_I2C_INTM_MRXOF BIT(1)
#define JZ4780_I2C_INTM_MRXUF BIT(0)
#define JZ4780_I2C_DC_READ BIT(8)
#define JZ4780_I2C_SDAHD_HDENB BIT(8)
#define JZ4780_I2C_ENB_I2C BIT(0)
#define JZ4780_I2CSHCNT_ADJUST(n) (((n) - 8) < 6 ? 6 : ((n) - 8))
#define JZ4780_I2CSLCNT_ADJUST(n) (((n) - 1) < 8 ? 8 : ((n) - 1))
#define JZ4780_I2CFHCNT_ADJUST(n) (((n) - 8) < 6 ? 6 : ((n) - 8))
#define JZ4780_I2CFLCNT_ADJUST(n) (((n) - 1) < 8 ? 8 : ((n) - 1))
#define JZ4780_I2C_FIFO_LEN 16
#define TX_LEVEL 3
#define RX_LEVEL (JZ4780_I2C_FIFO_LEN - TX_LEVEL - 1)
#define JZ4780_I2C_TIMEOUT 300
#define BUFSIZE 200
struct jz4780_i2c {
void __iomem *iomem;
int irq;
struct clk *clk;
struct i2c_adapter adap;
/* lock to protect rbuf and wbuf between xfer_rd/wr and irq handler */
spinlock_t lock;
/* beginning of lock scope */
unsigned char *rbuf;
int rd_total_len;
int rd_data_xfered;
int rd_cmd_xfered;
unsigned char *wbuf;
int wt_len;
int is_write;
int stop_hold;
int speed;
int data_buf[BUFSIZE];
int cmd_buf[BUFSIZE];
int cmd;
/* end of lock scope */
struct completion trans_waitq;
};
static inline unsigned short jz4780_i2c_readw(struct jz4780_i2c *i2c,
unsigned long offset)
{
return readw(i2c->iomem + offset);
}
static inline void jz4780_i2c_writew(struct jz4780_i2c *i2c,
unsigned long offset, unsigned short val)
{
writew(val, i2c->iomem + offset);
}
static int jz4780_i2c_disable(struct jz4780_i2c *i2c)
{
unsigned short regval;
unsigned long loops = 5;
jz4780_i2c_writew(i2c, JZ4780_I2C_ENB, 0);
do {
regval = jz4780_i2c_readw(i2c, JZ4780_I2C_ENSTA);
if (!(regval & JZ4780_I2C_ENB_I2C))
return 0;
usleep_range(5000, 15000);
} while (--loops);
dev_err(&i2c->adap.dev, "disable failed: ENSTA=0x%04x\n", regval);
return -ETIMEDOUT;
}
static int jz4780_i2c_enable(struct jz4780_i2c *i2c)
{
unsigned short regval;
unsigned long loops = 5;
jz4780_i2c_writew(i2c, JZ4780_I2C_ENB, 1);
do {
regval = jz4780_i2c_readw(i2c, JZ4780_I2C_ENSTA);
if (regval & JZ4780_I2C_ENB_I2C)
return 0;
usleep_range(5000, 15000);
} while (--loops);
dev_err(&i2c->adap.dev, "enable failed: ENSTA=0x%04x\n", regval);
return -ETIMEDOUT;
}
static int jz4780_i2c_set_target(struct jz4780_i2c *i2c, unsigned char address)
{
unsigned short regval;
unsigned long loops = 5;
do {
regval = jz4780_i2c_readw(i2c, JZ4780_I2C_STA);
if ((regval & JZ4780_I2C_STA_TFE) &&
!(regval & JZ4780_I2C_STA_MSTACT))
break;
usleep_range(5000, 15000);
} while (--loops);
if (loops) {
jz4780_i2c_writew(i2c, JZ4780_I2C_TAR, address);
return 0;
}
dev_err(&i2c->adap.dev,
"set device to address 0x%02x failed, STA=0x%04x\n",
address, regval);
return -ENXIO;
}
static int jz4780_i2c_set_speed(struct jz4780_i2c *i2c)
{
int dev_clk_khz = clk_get_rate(i2c->clk) / 1000;
int cnt_high = 0; /* HIGH period count of the SCL clock */
int cnt_low = 0; /* LOW period count of the SCL clock */
int cnt_period = 0; /* period count of the SCL clock */
int setup_time = 0;
int hold_time = 0;
unsigned short tmp = 0;
int i2c_clk = i2c->speed;
if (jz4780_i2c_disable(i2c))
dev_dbg(&i2c->adap.dev, "i2c not disabled\n");
/*
* 1 JZ4780_I2C cycle equals to cnt_period PCLK(i2c_clk)
* standard mode, min LOW and HIGH period are 4700 ns and 4000 ns
* fast mode, min LOW and HIGH period are 1300 ns and 600 ns
*/
cnt_period = dev_clk_khz / i2c_clk;
if (i2c_clk <= 100)
cnt_high = (cnt_period * 4000) / (4700 + 4000);
else
cnt_high = (cnt_period * 600) / (1300 + 600);
cnt_low = cnt_period - cnt_high;
/*
* NOTE: JZ4780_I2C_CTRL_REST can't set when i2c enabled, because
* normal read are 2 messages, we cannot disable i2c controller
* between these two messages, this means that we must always set
* JZ4780_I2C_CTRL_REST when init JZ4780_I2C_CTRL
*
*/
if (i2c_clk <= 100) {
tmp = JZ4780_I2C_CTRL_SPDS | JZ4780_I2C_CTRL_REST
| JZ4780_I2C_CTRL_SLVDIS | JZ4780_I2C_CTRL_MD;
jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
jz4780_i2c_writew(i2c, JZ4780_I2C_SHCNT,
JZ4780_I2CSHCNT_ADJUST(cnt_high));
jz4780_i2c_writew(i2c, JZ4780_I2C_SLCNT,
JZ4780_I2CSLCNT_ADJUST(cnt_low));
} else {
tmp = JZ4780_I2C_CTRL_SPDF | JZ4780_I2C_CTRL_REST
| JZ4780_I2C_CTRL_SLVDIS | JZ4780_I2C_CTRL_MD;
jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
jz4780_i2c_writew(i2c, JZ4780_I2C_FHCNT,
JZ4780_I2CFHCNT_ADJUST(cnt_high));
jz4780_i2c_writew(i2c, JZ4780_I2C_FLCNT,
JZ4780_I2CFLCNT_ADJUST(cnt_low));
}
/*
* a i2c device must internally provide a hold time at least 300ns
* tHD:DAT
* Standard Mode: min=300ns, max=3450ns
* Fast Mode: min=0ns, max=900ns
* tSU:DAT
* Standard Mode: min=250ns, max=infinite
* Fast Mode: min=100(250ns is recommended), max=infinite
*
* 1i2c_clk = 10^6 / dev_clk_khz
* on FPGA, dev_clk_khz = 12000, so 1i2c_clk = 1000/12 = 83ns
* on Pisces(1008M), dev_clk_khz=126000, so 1i2c_clk = 1000 / 126 = 8ns
*
* The actual hold time is (SDAHD + 1) * (i2c_clk period).
*
* Length of setup time calculated using (SDASU - 1) * (ic_clk_period)
*
*/
if (i2c_clk <= 100) { /* standard mode */
setup_time = 300;
hold_time = 400;
} else {
setup_time = 450;
hold_time = 450;
}
hold_time = ((hold_time * dev_clk_khz) / 1000000) - 1;
setup_time = ((setup_time * dev_clk_khz) / 1000000) + 1;
if (setup_time > 255)
setup_time = 255;
if (setup_time <= 0)
setup_time = 1;
jz4780_i2c_writew(i2c, JZ4780_I2C_SDASU, setup_time);
if (hold_time > 255)
hold_time = 255;
if (hold_time >= 0) {
/*i2c hold time enable */
hold_time |= JZ4780_I2C_SDAHD_HDENB;
jz4780_i2c_writew(i2c, JZ4780_I2C_SDAHD, hold_time);
} else {
/* disable hold time */
jz4780_i2c_writew(i2c, JZ4780_I2C_SDAHD, 0);
}
return 0;
}
static int jz4780_i2c_cleanup(struct jz4780_i2c *i2c)
{
int ret;
unsigned long flags;
unsigned short tmp;
spin_lock_irqsave(&i2c->lock, flags);
/* can send stop now if need */
tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
tmp &= ~JZ4780_I2C_CTRL_STPHLD;
jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
/* disable all interrupts first */
jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, 0);
/* then clear all interrupts */
jz4780_i2c_readw(i2c, JZ4780_I2C_CTXABRT);
jz4780_i2c_readw(i2c, JZ4780_I2C_CINTR);
/* then disable the controller */
tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
tmp &= ~JZ4780_I2C_ENB_I2C;
jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
udelay(10);
tmp |= JZ4780_I2C_ENB_I2C;
jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
spin_unlock_irqrestore(&i2c->lock, flags);
ret = jz4780_i2c_disable(i2c);
if (ret)
dev_err(&i2c->adap.dev,
"unable to disable device during cleanup!\n");
if (unlikely(jz4780_i2c_readw(i2c, JZ4780_I2C_INTM)
& jz4780_i2c_readw(i2c, JZ4780_I2C_INTST)))
dev_err(&i2c->adap.dev,
"device has interrupts after a complete cleanup!\n");
return ret;
}
static int jz4780_i2c_prepare(struct jz4780_i2c *i2c)
{
jz4780_i2c_set_speed(i2c);
return jz4780_i2c_enable(i2c);
}
static void jz4780_i2c_send_rcmd(struct jz4780_i2c *i2c, int cmd_count)
{
int i;
for (i = 0; i < cmd_count; i++)
jz4780_i2c_writew(i2c, JZ4780_I2C_DC, JZ4780_I2C_DC_READ);
}
static void jz4780_i2c_trans_done(struct jz4780_i2c *i2c)
{
jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, 0);
complete(&i2c->trans_waitq);
}
static irqreturn_t jz4780_i2c_irq(int irqno, void *dev_id)
{
unsigned short tmp;
unsigned short intst;
unsigned short intmsk;
struct jz4780_i2c *i2c = dev_id;
unsigned long flags;
spin_lock_irqsave(&i2c->lock, flags);
intmsk = jz4780_i2c_readw(i2c, JZ4780_I2C_INTM);
intst = jz4780_i2c_readw(i2c, JZ4780_I2C_INTST);
intst &= intmsk;
if (intst & JZ4780_I2C_INTST_TXABT) {
jz4780_i2c_trans_done(i2c);
goto done;
}
if (intst & JZ4780_I2C_INTST_RXOF) {
dev_dbg(&i2c->adap.dev, "received fifo overflow!\n");
jz4780_i2c_trans_done(i2c);
goto done;
}
/*
* When reading, always drain RX FIFO before we send more Read
* Commands to avoid fifo overrun
*/
if (i2c->is_write == 0) {
int rd_left;
while ((jz4780_i2c_readw(i2c, JZ4780_I2C_STA)
& JZ4780_I2C_STA_RFNE)) {
*(i2c->rbuf++) = jz4780_i2c_readw(i2c, JZ4780_I2C_DC)
& 0xff;
i2c->rd_data_xfered++;
if (i2c->rd_data_xfered == i2c->rd_total_len) {
jz4780_i2c_trans_done(i2c);
goto done;
}
}
rd_left = i2c->rd_total_len - i2c->rd_data_xfered;
if (rd_left <= JZ4780_I2C_FIFO_LEN)
jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, rd_left - 1);
}
if (intst & JZ4780_I2C_INTST_TXEMP) {
if (i2c->is_write == 0) {
int cmd_left = i2c->rd_total_len - i2c->rd_cmd_xfered;
int max_send = (JZ4780_I2C_FIFO_LEN - 1)
- (i2c->rd_cmd_xfered
- i2c->rd_data_xfered);
int cmd_to_send = min(cmd_left, max_send);
if (i2c->rd_cmd_xfered != 0)
cmd_to_send = min(cmd_to_send,
JZ4780_I2C_FIFO_LEN
- TX_LEVEL - 1);
if (cmd_to_send) {
jz4780_i2c_send_rcmd(i2c, cmd_to_send);
i2c->rd_cmd_xfered += cmd_to_send;
}
cmd_left = i2c->rd_total_len - i2c->rd_cmd_xfered;
if (cmd_left == 0) {
intmsk = jz4780_i2c_readw(i2c, JZ4780_I2C_INTM);
intmsk &= ~JZ4780_I2C_INTM_MTXEMP;
jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, intmsk);
tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
tmp &= ~JZ4780_I2C_CTRL_STPHLD;
jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
}
} else {
unsigned short data;
unsigned short i2c_sta;
i2c_sta = jz4780_i2c_readw(i2c, JZ4780_I2C_STA);
while ((i2c_sta & JZ4780_I2C_STA_TFNF) &&
(i2c->wt_len > 0)) {
i2c_sta = jz4780_i2c_readw(i2c, JZ4780_I2C_STA);
data = *i2c->wbuf;
data &= ~JZ4780_I2C_DC_READ;
jz4780_i2c_writew(i2c, JZ4780_I2C_DC,
data);
i2c->wbuf++;
i2c->wt_len--;
}
if (i2c->wt_len == 0) {
if (!i2c->stop_hold) {
tmp = jz4780_i2c_readw(i2c,
JZ4780_I2C_CTRL);
tmp &= ~JZ4780_I2C_CTRL_STPHLD;
jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL,
tmp);
}
jz4780_i2c_trans_done(i2c);
goto done;
}
}
}
done:
spin_unlock_irqrestore(&i2c->lock, flags);
return IRQ_HANDLED;
}
static void jz4780_i2c_txabrt(struct jz4780_i2c *i2c, int src)
{
int i;
dev_err(&i2c->adap.dev, "txabrt: 0x%08x\n", src);
dev_err(&i2c->adap.dev, "device addr=%x\n",
jz4780_i2c_readw(i2c, JZ4780_I2C_TAR));
dev_err(&i2c->adap.dev, "send cmd count:%d %d\n",
i2c->cmd, i2c->cmd_buf[i2c->cmd]);
dev_err(&i2c->adap.dev, "receive data count:%d %d\n",
i2c->cmd, i2c->data_buf[i2c->cmd]);
for (i = 0; i < 16; i++) {
if (src & BIT(i))
dev_dbg(&i2c->adap.dev, "I2C TXABRT[%d]=%s\n",
i, jz4780_i2c_abrt_src[i]);
}
}
static inline int jz4780_i2c_xfer_read(struct jz4780_i2c *i2c,
unsigned char *buf, int len, int cnt,
int idx)
{
int ret = 0;
long timeout;
int wait_time = JZ4780_I2C_TIMEOUT * (len + 5);
unsigned short tmp;
unsigned long flags;
memset(buf, 0, len);
spin_lock_irqsave(&i2c->lock, flags);
i2c->stop_hold = 0;
i2c->is_write = 0;
i2c->rbuf = buf;
i2c->rd_total_len = len;
i2c->rd_data_xfered = 0;
i2c->rd_cmd_xfered = 0;
if (len <= JZ4780_I2C_FIFO_LEN)
jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, len - 1);
else
jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, RX_LEVEL);
jz4780_i2c_writew(i2c, JZ4780_I2C_TXTL, TX_LEVEL);
jz4780_i2c_writew(i2c, JZ4780_I2C_INTM,
JZ4780_I2C_INTM_MRXFL | JZ4780_I2C_INTM_MTXEMP
| JZ4780_I2C_INTM_MTXABT | JZ4780_I2C_INTM_MRXOF);
tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
tmp |= JZ4780_I2C_CTRL_STPHLD;
jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
spin_unlock_irqrestore(&i2c->lock, flags);
timeout = wait_for_completion_timeout(&i2c->trans_waitq,
msecs_to_jiffies(wait_time));
if (!timeout) {
dev_err(&i2c->adap.dev, "irq read timeout\n");
dev_dbg(&i2c->adap.dev, "send cmd count:%d %d\n",
i2c->cmd, i2c->cmd_buf[i2c->cmd]);
dev_dbg(&i2c->adap.dev, "receive data count:%d %d\n",
i2c->cmd, i2c->data_buf[i2c->cmd]);
ret = -EIO;
}
tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_TXABRT);
if (tmp) {
jz4780_i2c_txabrt(i2c, tmp);
ret = -EIO;
}
return ret;
}
static inline int jz4780_i2c_xfer_write(struct jz4780_i2c *i2c,
unsigned char *buf, int len,
int cnt, int idx)
{
int ret = 0;
int wait_time = JZ4780_I2C_TIMEOUT * (len + 5);
long timeout;
unsigned short tmp;
unsigned long flags;
spin_lock_irqsave(&i2c->lock, flags);
if (idx < (cnt - 1))
i2c->stop_hold = 1;
else
i2c->stop_hold = 0;
i2c->is_write = 1;
i2c->wbuf = buf;
i2c->wt_len = len;
jz4780_i2c_writew(i2c, JZ4780_I2C_TXTL, TX_LEVEL);
jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, JZ4780_I2C_INTM_MTXEMP
| JZ4780_I2C_INTM_MTXABT);
tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
tmp |= JZ4780_I2C_CTRL_STPHLD;
jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
spin_unlock_irqrestore(&i2c->lock, flags);
timeout = wait_for_completion_timeout(&i2c->trans_waitq,
msecs_to_jiffies(wait_time));
if (timeout && !i2c->stop_hold) {
unsigned short i2c_sta;
int write_in_process;
timeout = JZ4780_I2C_TIMEOUT * 100;
for (; timeout > 0; timeout--) {
i2c_sta = jz4780_i2c_readw(i2c, JZ4780_I2C_STA);
write_in_process = (i2c_sta & JZ4780_I2C_STA_MSTACT) ||
!(i2c_sta & JZ4780_I2C_STA_TFE);
if (!write_in_process)
break;
udelay(10);
}
}
if (!timeout) {
dev_err(&i2c->adap.dev, "write wait timeout\n");
ret = -EIO;
}
tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_TXABRT);
if (tmp) {
jz4780_i2c_txabrt(i2c, tmp);
ret = -EIO;
}
return ret;
}
static int jz4780_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msg,
int count)
{
int i = -EIO;
int ret = 0;
struct jz4780_i2c *i2c = adap->algo_data;
ret = jz4780_i2c_prepare(i2c);
if (ret) {
dev_err(&i2c->adap.dev, "I2C prepare failed\n");
goto out;
}
if (msg->addr != jz4780_i2c_readw(i2c, JZ4780_I2C_TAR)) {
ret = jz4780_i2c_set_target(i2c, msg->addr);
if (ret)
goto out;
}
for (i = 0; i < count; i++, msg++) {
if (msg->flags & I2C_M_RD)
ret = jz4780_i2c_xfer_read(i2c, msg->buf, msg->len,
count, i);
else
ret = jz4780_i2c_xfer_write(i2c, msg->buf, msg->len,
count, i);
if (ret)
goto out;
}
ret = i;
out:
jz4780_i2c_cleanup(i2c);
return ret;
}
static u32 jz4780_i2c_functionality(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}
static const struct i2c_algorithm jz4780_i2c_algorithm = {
.master_xfer = jz4780_i2c_xfer,
.functionality = jz4780_i2c_functionality,
};
static const struct of_device_id jz4780_i2c_of_matches[] = {
{ .compatible = "ingenic,jz4780-i2c", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, jz4780_i2c_of_matches);
static int jz4780_i2c_probe(struct platform_device *pdev)
{
int ret = 0;
unsigned int clk_freq = 0;
unsigned short tmp;
struct resource *r;
struct jz4780_i2c *i2c;
i2c = devm_kzalloc(&pdev->dev, sizeof(struct jz4780_i2c), GFP_KERNEL);
if (!i2c)
return -ENOMEM;
i2c->adap.owner = THIS_MODULE;
i2c->adap.algo = &jz4780_i2c_algorithm;
i2c->adap.algo_data = i2c;
i2c->adap.retries = 5;
i2c->adap.dev.parent = &pdev->dev;
i2c->adap.dev.of_node = pdev->dev.of_node;
sprintf(i2c->adap.name, "%s", pdev->name);
init_completion(&i2c->trans_waitq);
spin_lock_init(&i2c->lock);
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
i2c->iomem = devm_ioremap_resource(&pdev->dev, r);
if (IS_ERR(i2c->iomem))
return PTR_ERR(i2c->iomem);
platform_set_drvdata(pdev, i2c);
i2c->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(i2c->clk))
return PTR_ERR(i2c->clk);
ret = clk_prepare_enable(i2c->clk);
if (ret)
return ret;
ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency",
&clk_freq);
if (ret) {
dev_err(&pdev->dev, "clock-frequency not specified in DT\n");
goto err;
}
i2c->speed = clk_freq / 1000;
if (i2c->speed == 0) {
ret = -EINVAL;
dev_err(&pdev->dev, "clock-frequency minimum is 1000\n");
goto err;
}
jz4780_i2c_set_speed(i2c);
dev_info(&pdev->dev, "Bus frequency is %d KHz\n", i2c->speed);
tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
tmp &= ~JZ4780_I2C_CTRL_STPHLD;
jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, 0x0);
i2c->irq = platform_get_irq(pdev, 0);
ret = devm_request_irq(&pdev->dev, i2c->irq, jz4780_i2c_irq, 0,
dev_name(&pdev->dev), i2c);
if (ret)
goto err;
ret = i2c_add_adapter(&i2c->adap);
if (ret < 0)
goto err;
return 0;
err:
clk_disable_unprepare(i2c->clk);
return ret;
}
static int jz4780_i2c_remove(struct platform_device *pdev)
{
struct jz4780_i2c *i2c = platform_get_drvdata(pdev);
clk_disable_unprepare(i2c->clk);
i2c_del_adapter(&i2c->adap);
return 0;
}
static struct platform_driver jz4780_i2c_driver = {
.probe = jz4780_i2c_probe,
.remove = jz4780_i2c_remove,
.driver = {
.name = "jz4780-i2c",
.of_match_table = of_match_ptr(jz4780_i2c_of_matches),
},
};
module_platform_driver(jz4780_i2c_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("ztyan<ztyan@ingenic.cn>");
MODULE_DESCRIPTION("i2c driver for JZ4780 SoCs");
Reference in New Issue View Git Blame Copy Permalink