mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-06 02:24:14 +08:00
9a6b94796a
platform_get_irq() returns an error code, but the spi-xlp driver ignores it and always returns -EINVAL. This is not correct and, prevents -EPROBE_DEFER from being propagated properly. Notice that platform_get_irq() no longer returns 0 on error: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e330b9a6bb35dc7097a4f02cb1ae7b6f96df92af Print and propagate the return value of platform_get_irq on failure. This issue was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Mark Brown <broonie@kernel.org>
470 lines
12 KiB
C
470 lines
12 KiB
C
/*
|
|
* Copyright (C) 2003-2015 Broadcom Corporation
|
|
* All Rights Reserved
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 (GPL v2)
|
|
* as published by the Free Software Foundation.
|
|
*
|
|
* 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.
|
|
*/
|
|
#include <linux/acpi.h>
|
|
#include <linux/clk.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/spi/spi.h>
|
|
#include <linux/of.h>
|
|
#include <linux/interrupt.h>
|
|
|
|
/* SPI Configuration Register */
|
|
#define XLP_SPI_CONFIG 0x00
|
|
#define XLP_SPI_CPHA BIT(0)
|
|
#define XLP_SPI_CPOL BIT(1)
|
|
#define XLP_SPI_CS_POL BIT(2)
|
|
#define XLP_SPI_TXMISO_EN BIT(3)
|
|
#define XLP_SPI_TXMOSI_EN BIT(4)
|
|
#define XLP_SPI_RXMISO_EN BIT(5)
|
|
#define XLP_SPI_CS_LSBFE BIT(10)
|
|
#define XLP_SPI_RXCAP_EN BIT(11)
|
|
|
|
/* SPI Frequency Divider Register */
|
|
#define XLP_SPI_FDIV 0x04
|
|
|
|
/* SPI Command Register */
|
|
#define XLP_SPI_CMD 0x08
|
|
#define XLP_SPI_CMD_IDLE_MASK 0x0
|
|
#define XLP_SPI_CMD_TX_MASK 0x1
|
|
#define XLP_SPI_CMD_RX_MASK 0x2
|
|
#define XLP_SPI_CMD_TXRX_MASK 0x3
|
|
#define XLP_SPI_CMD_CONT BIT(4)
|
|
#define XLP_SPI_XFR_BITCNT_SHIFT 16
|
|
|
|
/* SPI Status Register */
|
|
#define XLP_SPI_STATUS 0x0c
|
|
#define XLP_SPI_XFR_PENDING BIT(0)
|
|
#define XLP_SPI_XFR_DONE BIT(1)
|
|
#define XLP_SPI_TX_INT BIT(2)
|
|
#define XLP_SPI_RX_INT BIT(3)
|
|
#define XLP_SPI_TX_UF BIT(4)
|
|
#define XLP_SPI_RX_OF BIT(5)
|
|
#define XLP_SPI_STAT_MASK 0x3f
|
|
|
|
/* SPI Interrupt Enable Register */
|
|
#define XLP_SPI_INTR_EN 0x10
|
|
#define XLP_SPI_INTR_DONE BIT(0)
|
|
#define XLP_SPI_INTR_TXTH BIT(1)
|
|
#define XLP_SPI_INTR_RXTH BIT(2)
|
|
#define XLP_SPI_INTR_TXUF BIT(3)
|
|
#define XLP_SPI_INTR_RXOF BIT(4)
|
|
|
|
/* SPI FIFO Threshold Register */
|
|
#define XLP_SPI_FIFO_THRESH 0x14
|
|
|
|
/* SPI FIFO Word Count Register */
|
|
#define XLP_SPI_FIFO_WCNT 0x18
|
|
#define XLP_SPI_RXFIFO_WCNT_MASK 0xf
|
|
#define XLP_SPI_TXFIFO_WCNT_MASK 0xf0
|
|
#define XLP_SPI_TXFIFO_WCNT_SHIFT 4
|
|
|
|
/* SPI Transmit Data FIFO Register */
|
|
#define XLP_SPI_TXDATA_FIFO 0x1c
|
|
|
|
/* SPI Receive Data FIFO Register */
|
|
#define XLP_SPI_RXDATA_FIFO 0x20
|
|
|
|
/* SPI System Control Register */
|
|
#define XLP_SPI_SYSCTRL 0x100
|
|
#define XLP_SPI_SYS_RESET BIT(0)
|
|
#define XLP_SPI_SYS_CLKDIS BIT(1)
|
|
#define XLP_SPI_SYS_PMEN BIT(8)
|
|
|
|
#define SPI_CS_OFFSET 0x40
|
|
#define XLP_SPI_TXRXTH 0x80
|
|
#define XLP_SPI_FIFO_SIZE 8
|
|
#define XLP_SPI_MAX_CS 4
|
|
#define XLP_SPI_DEFAULT_FREQ 133333333
|
|
#define XLP_SPI_FDIV_MIN 4
|
|
#define XLP_SPI_FDIV_MAX 65535
|
|
/*
|
|
* SPI can transfer only 28 bytes properly at a time. So split the
|
|
* transfer into 28 bytes size.
|
|
*/
|
|
#define XLP_SPI_XFER_SIZE 28
|
|
|
|
struct xlp_spi_priv {
|
|
struct device dev; /* device structure */
|
|
void __iomem *base; /* spi registers base address */
|
|
const u8 *tx_buf; /* tx data buffer */
|
|
u8 *rx_buf; /* rx data buffer */
|
|
int tx_len; /* tx xfer length */
|
|
int rx_len; /* rx xfer length */
|
|
int txerrors; /* TXFIFO underflow count */
|
|
int rxerrors; /* RXFIFO overflow count */
|
|
int cs; /* slave device chip select */
|
|
u32 spi_clk; /* spi clock frequency */
|
|
bool cmd_cont; /* cs active */
|
|
struct completion done; /* completion notification */
|
|
};
|
|
|
|
static inline u32 xlp_spi_reg_read(struct xlp_spi_priv *priv,
|
|
int cs, int regoff)
|
|
{
|
|
return readl(priv->base + regoff + cs * SPI_CS_OFFSET);
|
|
}
|
|
|
|
static inline void xlp_spi_reg_write(struct xlp_spi_priv *priv, int cs,
|
|
int regoff, u32 val)
|
|
{
|
|
writel(val, priv->base + regoff + cs * SPI_CS_OFFSET);
|
|
}
|
|
|
|
static inline void xlp_spi_sysctl_write(struct xlp_spi_priv *priv,
|
|
int regoff, u32 val)
|
|
{
|
|
writel(val, priv->base + regoff);
|
|
}
|
|
|
|
/*
|
|
* Setup global SPI_SYSCTRL register for all SPI channels.
|
|
*/
|
|
static void xlp_spi_sysctl_setup(struct xlp_spi_priv *xspi)
|
|
{
|
|
int cs;
|
|
|
|
for (cs = 0; cs < XLP_SPI_MAX_CS; cs++)
|
|
xlp_spi_sysctl_write(xspi, XLP_SPI_SYSCTRL,
|
|
XLP_SPI_SYS_RESET << cs);
|
|
xlp_spi_sysctl_write(xspi, XLP_SPI_SYSCTRL, XLP_SPI_SYS_PMEN);
|
|
}
|
|
|
|
static int xlp_spi_setup(struct spi_device *spi)
|
|
{
|
|
struct xlp_spi_priv *xspi;
|
|
u32 fdiv, cfg;
|
|
int cs;
|
|
|
|
xspi = spi_master_get_devdata(spi->master);
|
|
cs = spi->chip_select;
|
|
/*
|
|
* The value of fdiv must be between 4 and 65535.
|
|
*/
|
|
fdiv = DIV_ROUND_UP(xspi->spi_clk, spi->max_speed_hz);
|
|
if (fdiv > XLP_SPI_FDIV_MAX)
|
|
fdiv = XLP_SPI_FDIV_MAX;
|
|
else if (fdiv < XLP_SPI_FDIV_MIN)
|
|
fdiv = XLP_SPI_FDIV_MIN;
|
|
|
|
xlp_spi_reg_write(xspi, cs, XLP_SPI_FDIV, fdiv);
|
|
xlp_spi_reg_write(xspi, cs, XLP_SPI_FIFO_THRESH, XLP_SPI_TXRXTH);
|
|
cfg = xlp_spi_reg_read(xspi, cs, XLP_SPI_CONFIG);
|
|
if (spi->mode & SPI_CPHA)
|
|
cfg |= XLP_SPI_CPHA;
|
|
else
|
|
cfg &= ~XLP_SPI_CPHA;
|
|
if (spi->mode & SPI_CPOL)
|
|
cfg |= XLP_SPI_CPOL;
|
|
else
|
|
cfg &= ~XLP_SPI_CPOL;
|
|
if (!(spi->mode & SPI_CS_HIGH))
|
|
cfg |= XLP_SPI_CS_POL;
|
|
else
|
|
cfg &= ~XLP_SPI_CS_POL;
|
|
if (spi->mode & SPI_LSB_FIRST)
|
|
cfg |= XLP_SPI_CS_LSBFE;
|
|
else
|
|
cfg &= ~XLP_SPI_CS_LSBFE;
|
|
|
|
cfg |= XLP_SPI_TXMOSI_EN | XLP_SPI_RXMISO_EN;
|
|
if (fdiv == 4)
|
|
cfg |= XLP_SPI_RXCAP_EN;
|
|
xlp_spi_reg_write(xspi, cs, XLP_SPI_CONFIG, cfg);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void xlp_spi_read_rxfifo(struct xlp_spi_priv *xspi)
|
|
{
|
|
u32 rx_data, rxfifo_cnt;
|
|
int i, j, nbytes;
|
|
|
|
rxfifo_cnt = xlp_spi_reg_read(xspi, xspi->cs, XLP_SPI_FIFO_WCNT);
|
|
rxfifo_cnt &= XLP_SPI_RXFIFO_WCNT_MASK;
|
|
while (rxfifo_cnt) {
|
|
rx_data = xlp_spi_reg_read(xspi, xspi->cs, XLP_SPI_RXDATA_FIFO);
|
|
j = 0;
|
|
nbytes = min(xspi->rx_len, 4);
|
|
for (i = nbytes - 1; i >= 0; i--, j++)
|
|
xspi->rx_buf[i] = (rx_data >> (j * 8)) & 0xff;
|
|
|
|
xspi->rx_len -= nbytes;
|
|
xspi->rx_buf += nbytes;
|
|
rxfifo_cnt--;
|
|
}
|
|
}
|
|
|
|
static void xlp_spi_fill_txfifo(struct xlp_spi_priv *xspi)
|
|
{
|
|
u32 tx_data, txfifo_cnt;
|
|
int i, j, nbytes;
|
|
|
|
txfifo_cnt = xlp_spi_reg_read(xspi, xspi->cs, XLP_SPI_FIFO_WCNT);
|
|
txfifo_cnt &= XLP_SPI_TXFIFO_WCNT_MASK;
|
|
txfifo_cnt >>= XLP_SPI_TXFIFO_WCNT_SHIFT;
|
|
while (xspi->tx_len && (txfifo_cnt < XLP_SPI_FIFO_SIZE)) {
|
|
j = 0;
|
|
tx_data = 0;
|
|
nbytes = min(xspi->tx_len, 4);
|
|
for (i = nbytes - 1; i >= 0; i--, j++)
|
|
tx_data |= xspi->tx_buf[i] << (j * 8);
|
|
|
|
xlp_spi_reg_write(xspi, xspi->cs, XLP_SPI_TXDATA_FIFO, tx_data);
|
|
xspi->tx_len -= nbytes;
|
|
xspi->tx_buf += nbytes;
|
|
txfifo_cnt++;
|
|
}
|
|
}
|
|
|
|
static irqreturn_t xlp_spi_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct xlp_spi_priv *xspi = dev_id;
|
|
u32 stat;
|
|
|
|
stat = xlp_spi_reg_read(xspi, xspi->cs, XLP_SPI_STATUS) &
|
|
XLP_SPI_STAT_MASK;
|
|
if (!stat)
|
|
return IRQ_NONE;
|
|
|
|
if (stat & XLP_SPI_TX_INT) {
|
|
if (xspi->tx_len)
|
|
xlp_spi_fill_txfifo(xspi);
|
|
if (stat & XLP_SPI_TX_UF)
|
|
xspi->txerrors++;
|
|
}
|
|
|
|
if (stat & XLP_SPI_RX_INT) {
|
|
if (xspi->rx_len)
|
|
xlp_spi_read_rxfifo(xspi);
|
|
if (stat & XLP_SPI_RX_OF)
|
|
xspi->rxerrors++;
|
|
}
|
|
|
|
/* write status back to clear interrupts */
|
|
xlp_spi_reg_write(xspi, xspi->cs, XLP_SPI_STATUS, stat);
|
|
if (stat & XLP_SPI_XFR_DONE)
|
|
complete(&xspi->done);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static void xlp_spi_send_cmd(struct xlp_spi_priv *xspi, int xfer_len,
|
|
int cmd_cont)
|
|
{
|
|
u32 cmd = 0;
|
|
|
|
if (xspi->tx_buf)
|
|
cmd |= XLP_SPI_CMD_TX_MASK;
|
|
if (xspi->rx_buf)
|
|
cmd |= XLP_SPI_CMD_RX_MASK;
|
|
if (cmd_cont)
|
|
cmd |= XLP_SPI_CMD_CONT;
|
|
cmd |= ((xfer_len * 8 - 1) << XLP_SPI_XFR_BITCNT_SHIFT);
|
|
xlp_spi_reg_write(xspi, xspi->cs, XLP_SPI_CMD, cmd);
|
|
}
|
|
|
|
static int xlp_spi_xfer_block(struct xlp_spi_priv *xs,
|
|
const unsigned char *tx_buf,
|
|
unsigned char *rx_buf, int xfer_len, int cmd_cont)
|
|
{
|
|
int timeout;
|
|
u32 intr_mask = 0;
|
|
|
|
xs->tx_buf = tx_buf;
|
|
xs->rx_buf = rx_buf;
|
|
xs->tx_len = (xs->tx_buf == NULL) ? 0 : xfer_len;
|
|
xs->rx_len = (xs->rx_buf == NULL) ? 0 : xfer_len;
|
|
xs->txerrors = xs->rxerrors = 0;
|
|
|
|
/* fill TXDATA_FIFO, then send the CMD */
|
|
if (xs->tx_len)
|
|
xlp_spi_fill_txfifo(xs);
|
|
|
|
xlp_spi_send_cmd(xs, xfer_len, cmd_cont);
|
|
|
|
/*
|
|
* We are getting some spurious tx interrupts, so avoid enabling
|
|
* tx interrupts when only rx is in process.
|
|
* Enable all the interrupts in tx case.
|
|
*/
|
|
if (xs->tx_len)
|
|
intr_mask |= XLP_SPI_INTR_TXTH | XLP_SPI_INTR_TXUF |
|
|
XLP_SPI_INTR_RXTH | XLP_SPI_INTR_RXOF;
|
|
else
|
|
intr_mask |= XLP_SPI_INTR_RXTH | XLP_SPI_INTR_RXOF;
|
|
|
|
intr_mask |= XLP_SPI_INTR_DONE;
|
|
xlp_spi_reg_write(xs, xs->cs, XLP_SPI_INTR_EN, intr_mask);
|
|
|
|
timeout = wait_for_completion_timeout(&xs->done,
|
|
msecs_to_jiffies(1000));
|
|
/* Disable interrupts */
|
|
xlp_spi_reg_write(xs, xs->cs, XLP_SPI_INTR_EN, 0x0);
|
|
if (!timeout) {
|
|
dev_err(&xs->dev, "xfer timedout!\n");
|
|
goto out;
|
|
}
|
|
if (xs->txerrors || xs->rxerrors)
|
|
dev_err(&xs->dev, "Over/Underflow rx %d tx %d xfer %d!\n",
|
|
xs->rxerrors, xs->txerrors, xfer_len);
|
|
|
|
return xfer_len;
|
|
out:
|
|
return -ETIMEDOUT;
|
|
}
|
|
|
|
static int xlp_spi_txrx_bufs(struct xlp_spi_priv *xs, struct spi_transfer *t)
|
|
{
|
|
int bytesleft, sz;
|
|
unsigned char *rx_buf;
|
|
const unsigned char *tx_buf;
|
|
|
|
tx_buf = t->tx_buf;
|
|
rx_buf = t->rx_buf;
|
|
bytesleft = t->len;
|
|
while (bytesleft) {
|
|
if (bytesleft > XLP_SPI_XFER_SIZE)
|
|
sz = xlp_spi_xfer_block(xs, tx_buf, rx_buf,
|
|
XLP_SPI_XFER_SIZE, 1);
|
|
else
|
|
sz = xlp_spi_xfer_block(xs, tx_buf, rx_buf,
|
|
bytesleft, xs->cmd_cont);
|
|
if (sz < 0)
|
|
return sz;
|
|
bytesleft -= sz;
|
|
if (tx_buf)
|
|
tx_buf += sz;
|
|
if (rx_buf)
|
|
rx_buf += sz;
|
|
}
|
|
return bytesleft;
|
|
}
|
|
|
|
static int xlp_spi_transfer_one(struct spi_master *master,
|
|
struct spi_device *spi,
|
|
struct spi_transfer *t)
|
|
{
|
|
struct xlp_spi_priv *xspi = spi_master_get_devdata(master);
|
|
int ret = 0;
|
|
|
|
xspi->cs = spi->chip_select;
|
|
xspi->dev = spi->dev;
|
|
|
|
if (spi_transfer_is_last(master, t))
|
|
xspi->cmd_cont = 0;
|
|
else
|
|
xspi->cmd_cont = 1;
|
|
|
|
if (xlp_spi_txrx_bufs(xspi, t))
|
|
ret = -EIO;
|
|
|
|
spi_finalize_current_transfer(master);
|
|
return ret;
|
|
}
|
|
|
|
static int xlp_spi_probe(struct platform_device *pdev)
|
|
{
|
|
struct spi_master *master;
|
|
struct xlp_spi_priv *xspi;
|
|
struct resource *res;
|
|
struct clk *clk;
|
|
int irq, err;
|
|
|
|
xspi = devm_kzalloc(&pdev->dev, sizeof(*xspi), GFP_KERNEL);
|
|
if (!xspi)
|
|
return -ENOMEM;
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
xspi->base = devm_ioremap_resource(&pdev->dev, res);
|
|
if (IS_ERR(xspi->base))
|
|
return PTR_ERR(xspi->base);
|
|
|
|
irq = platform_get_irq(pdev, 0);
|
|
if (irq < 0) {
|
|
dev_err(&pdev->dev, "no IRQ resource found: %d\n", irq);
|
|
return irq;
|
|
}
|
|
err = devm_request_irq(&pdev->dev, irq, xlp_spi_interrupt, 0,
|
|
pdev->name, xspi);
|
|
if (err) {
|
|
dev_err(&pdev->dev, "unable to request irq %d\n", irq);
|
|
return err;
|
|
}
|
|
|
|
clk = devm_clk_get(&pdev->dev, NULL);
|
|
if (IS_ERR(clk)) {
|
|
dev_err(&pdev->dev, "could not get spi clock\n");
|
|
return PTR_ERR(clk);
|
|
}
|
|
|
|
xspi->spi_clk = clk_get_rate(clk);
|
|
|
|
master = spi_alloc_master(&pdev->dev, 0);
|
|
if (!master) {
|
|
dev_err(&pdev->dev, "could not alloc master\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
master->bus_num = 0;
|
|
master->num_chipselect = XLP_SPI_MAX_CS;
|
|
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
|
|
master->setup = xlp_spi_setup;
|
|
master->transfer_one = xlp_spi_transfer_one;
|
|
master->dev.of_node = pdev->dev.of_node;
|
|
|
|
init_completion(&xspi->done);
|
|
spi_master_set_devdata(master, xspi);
|
|
xlp_spi_sysctl_setup(xspi);
|
|
|
|
/* register spi controller */
|
|
err = devm_spi_register_master(&pdev->dev, master);
|
|
if (err) {
|
|
dev_err(&pdev->dev, "spi register master failed!\n");
|
|
spi_master_put(master);
|
|
return err;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_ACPI
|
|
static const struct acpi_device_id xlp_spi_acpi_match[] = {
|
|
{ "BRCM900D", 0 },
|
|
{ "CAV900D", 0 },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(acpi, xlp_spi_acpi_match);
|
|
#endif
|
|
|
|
static const struct of_device_id xlp_spi_dt_id[] = {
|
|
{ .compatible = "netlogic,xlp832-spi" },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(of, xlp_spi_dt_id);
|
|
|
|
static struct platform_driver xlp_spi_driver = {
|
|
.probe = xlp_spi_probe,
|
|
.driver = {
|
|
.name = "xlp-spi",
|
|
.of_match_table = xlp_spi_dt_id,
|
|
.acpi_match_table = ACPI_PTR(xlp_spi_acpi_match),
|
|
},
|
|
};
|
|
module_platform_driver(xlp_spi_driver);
|
|
|
|
MODULE_AUTHOR("Kamlakant Patel <kamlakant.patel@broadcom.com>");
|
|
MODULE_DESCRIPTION("Netlogic XLP SPI controller driver");
|
|
MODULE_LICENSE("GPL v2");
|