Revision dc280d93623927570da279e99393879dbbab39e7 authored by Thomas Gleixner on 21 December 2016, 19:19:49 UTC, committed by Thomas Gleixner on 25 December 2016, 09:47:42 UTC
Developers manage to overwrite states blindly without thought. That's fatal and hard to debug. Add sanity checks to make it fail. This requries to restructure the code so that the dynamic state allocation happens in the same lock protected section as the actual store. Otherwise the previous assignment of 'Reserved' to the name field would trigger the overwrite check. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Link: http://lkml.kernel.org/r/20161221192111.675234535@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
1 parent 59fefd0
spi-coldfire-qspi.c
/*
* Freescale/Motorola Coldfire Queued SPI driver
*
* Copyright 2010 Steven King <sfking@fdwdc.com>
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/platform_device.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/spi/spi.h>
#include <linux/pm_runtime.h>
#include <asm/coldfire.h>
#include <asm/mcfsim.h>
#include <asm/mcfqspi.h>
#define DRIVER_NAME "mcfqspi"
#define MCFQSPI_BUSCLK (MCF_BUSCLK / 2)
#define MCFQSPI_QMR 0x00
#define MCFQSPI_QMR_MSTR 0x8000
#define MCFQSPI_QMR_CPOL 0x0200
#define MCFQSPI_QMR_CPHA 0x0100
#define MCFQSPI_QDLYR 0x04
#define MCFQSPI_QDLYR_SPE 0x8000
#define MCFQSPI_QWR 0x08
#define MCFQSPI_QWR_HALT 0x8000
#define MCFQSPI_QWR_WREN 0x4000
#define MCFQSPI_QWR_CSIV 0x1000
#define MCFQSPI_QIR 0x0C
#define MCFQSPI_QIR_WCEFB 0x8000
#define MCFQSPI_QIR_ABRTB 0x4000
#define MCFQSPI_QIR_ABRTL 0x1000
#define MCFQSPI_QIR_WCEFE 0x0800
#define MCFQSPI_QIR_ABRTE 0x0400
#define MCFQSPI_QIR_SPIFE 0x0100
#define MCFQSPI_QIR_WCEF 0x0008
#define MCFQSPI_QIR_ABRT 0x0004
#define MCFQSPI_QIR_SPIF 0x0001
#define MCFQSPI_QAR 0x010
#define MCFQSPI_QAR_TXBUF 0x00
#define MCFQSPI_QAR_RXBUF 0x10
#define MCFQSPI_QAR_CMDBUF 0x20
#define MCFQSPI_QDR 0x014
#define MCFQSPI_QCR 0x014
#define MCFQSPI_QCR_CONT 0x8000
#define MCFQSPI_QCR_BITSE 0x4000
#define MCFQSPI_QCR_DT 0x2000
struct mcfqspi {
void __iomem *iobase;
int irq;
struct clk *clk;
struct mcfqspi_cs_control *cs_control;
wait_queue_head_t waitq;
};
static void mcfqspi_wr_qmr(struct mcfqspi *mcfqspi, u16 val)
{
writew(val, mcfqspi->iobase + MCFQSPI_QMR);
}
static void mcfqspi_wr_qdlyr(struct mcfqspi *mcfqspi, u16 val)
{
writew(val, mcfqspi->iobase + MCFQSPI_QDLYR);
}
static u16 mcfqspi_rd_qdlyr(struct mcfqspi *mcfqspi)
{
return readw(mcfqspi->iobase + MCFQSPI_QDLYR);
}
static void mcfqspi_wr_qwr(struct mcfqspi *mcfqspi, u16 val)
{
writew(val, mcfqspi->iobase + MCFQSPI_QWR);
}
static void mcfqspi_wr_qir(struct mcfqspi *mcfqspi, u16 val)
{
writew(val, mcfqspi->iobase + MCFQSPI_QIR);
}
static void mcfqspi_wr_qar(struct mcfqspi *mcfqspi, u16 val)
{
writew(val, mcfqspi->iobase + MCFQSPI_QAR);
}
static void mcfqspi_wr_qdr(struct mcfqspi *mcfqspi, u16 val)
{
writew(val, mcfqspi->iobase + MCFQSPI_QDR);
}
static u16 mcfqspi_rd_qdr(struct mcfqspi *mcfqspi)
{
return readw(mcfqspi->iobase + MCFQSPI_QDR);
}
static void mcfqspi_cs_select(struct mcfqspi *mcfqspi, u8 chip_select,
bool cs_high)
{
mcfqspi->cs_control->select(mcfqspi->cs_control, chip_select, cs_high);
}
static void mcfqspi_cs_deselect(struct mcfqspi *mcfqspi, u8 chip_select,
bool cs_high)
{
mcfqspi->cs_control->deselect(mcfqspi->cs_control, chip_select, cs_high);
}
static int mcfqspi_cs_setup(struct mcfqspi *mcfqspi)
{
return (mcfqspi->cs_control->setup) ?
mcfqspi->cs_control->setup(mcfqspi->cs_control) : 0;
}
static void mcfqspi_cs_teardown(struct mcfqspi *mcfqspi)
{
if (mcfqspi->cs_control->teardown)
mcfqspi->cs_control->teardown(mcfqspi->cs_control);
}
static u8 mcfqspi_qmr_baud(u32 speed_hz)
{
return clamp((MCFQSPI_BUSCLK + speed_hz - 1) / speed_hz, 2u, 255u);
}
static bool mcfqspi_qdlyr_spe(struct mcfqspi *mcfqspi)
{
return mcfqspi_rd_qdlyr(mcfqspi) & MCFQSPI_QDLYR_SPE;
}
static irqreturn_t mcfqspi_irq_handler(int this_irq, void *dev_id)
{
struct mcfqspi *mcfqspi = dev_id;
/* clear interrupt */
mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE | MCFQSPI_QIR_SPIF);
wake_up(&mcfqspi->waitq);
return IRQ_HANDLED;
}
static void mcfqspi_transfer_msg8(struct mcfqspi *mcfqspi, unsigned count,
const u8 *txbuf, u8 *rxbuf)
{
unsigned i, n, offset = 0;
n = min(count, 16u);
mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
for (i = 0; i < n; ++i)
mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
if (txbuf)
for (i = 0; i < n; ++i)
mcfqspi_wr_qdr(mcfqspi, *txbuf++);
else
for (i = 0; i < count; ++i)
mcfqspi_wr_qdr(mcfqspi, 0);
count -= n;
if (count) {
u16 qwr = 0xf08;
mcfqspi_wr_qwr(mcfqspi, 0x700);
mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
do {
wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
mcfqspi_wr_qwr(mcfqspi, qwr);
mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
if (rxbuf) {
mcfqspi_wr_qar(mcfqspi,
MCFQSPI_QAR_RXBUF + offset);
for (i = 0; i < 8; ++i)
*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
}
n = min(count, 8u);
if (txbuf) {
mcfqspi_wr_qar(mcfqspi,
MCFQSPI_QAR_TXBUF + offset);
for (i = 0; i < n; ++i)
mcfqspi_wr_qdr(mcfqspi, *txbuf++);
}
qwr = (offset ? 0x808 : 0) + ((n - 1) << 8);
offset ^= 8;
count -= n;
} while (count);
wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
mcfqspi_wr_qwr(mcfqspi, qwr);
mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
if (rxbuf) {
mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
for (i = 0; i < 8; ++i)
*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
offset ^= 8;
}
} else {
mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
}
wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
if (rxbuf) {
mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
for (i = 0; i < n; ++i)
*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
}
}
static void mcfqspi_transfer_msg16(struct mcfqspi *mcfqspi, unsigned count,
const u16 *txbuf, u16 *rxbuf)
{
unsigned i, n, offset = 0;
n = min(count, 16u);
mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
for (i = 0; i < n; ++i)
mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
if (txbuf)
for (i = 0; i < n; ++i)
mcfqspi_wr_qdr(mcfqspi, *txbuf++);
else
for (i = 0; i < count; ++i)
mcfqspi_wr_qdr(mcfqspi, 0);
count -= n;
if (count) {
u16 qwr = 0xf08;
mcfqspi_wr_qwr(mcfqspi, 0x700);
mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
do {
wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
mcfqspi_wr_qwr(mcfqspi, qwr);
mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
if (rxbuf) {
mcfqspi_wr_qar(mcfqspi,
MCFQSPI_QAR_RXBUF + offset);
for (i = 0; i < 8; ++i)
*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
}
n = min(count, 8u);
if (txbuf) {
mcfqspi_wr_qar(mcfqspi,
MCFQSPI_QAR_TXBUF + offset);
for (i = 0; i < n; ++i)
mcfqspi_wr_qdr(mcfqspi, *txbuf++);
}
qwr = (offset ? 0x808 : 0x000) + ((n - 1) << 8);
offset ^= 8;
count -= n;
} while (count);
wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
mcfqspi_wr_qwr(mcfqspi, qwr);
mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
if (rxbuf) {
mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
for (i = 0; i < 8; ++i)
*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
offset ^= 8;
}
} else {
mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
}
wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
if (rxbuf) {
mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
for (i = 0; i < n; ++i)
*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
}
}
static void mcfqspi_set_cs(struct spi_device *spi, bool enable)
{
struct mcfqspi *mcfqspi = spi_master_get_devdata(spi->master);
bool cs_high = spi->mode & SPI_CS_HIGH;
if (enable)
mcfqspi_cs_select(mcfqspi, spi->chip_select, cs_high);
else
mcfqspi_cs_deselect(mcfqspi, spi->chip_select, cs_high);
}
static int mcfqspi_transfer_one(struct spi_master *master,
struct spi_device *spi,
struct spi_transfer *t)
{
struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
u16 qmr = MCFQSPI_QMR_MSTR;
qmr |= t->bits_per_word << 10;
if (spi->mode & SPI_CPHA)
qmr |= MCFQSPI_QMR_CPHA;
if (spi->mode & SPI_CPOL)
qmr |= MCFQSPI_QMR_CPOL;
qmr |= mcfqspi_qmr_baud(t->speed_hz);
mcfqspi_wr_qmr(mcfqspi, qmr);
mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE);
if (t->bits_per_word == 8)
mcfqspi_transfer_msg8(mcfqspi, t->len, t->tx_buf, t->rx_buf);
else
mcfqspi_transfer_msg16(mcfqspi, t->len / 2, t->tx_buf,
t->rx_buf);
mcfqspi_wr_qir(mcfqspi, 0);
return 0;
}
static int mcfqspi_setup(struct spi_device *spi)
{
mcfqspi_cs_deselect(spi_master_get_devdata(spi->master),
spi->chip_select, spi->mode & SPI_CS_HIGH);
dev_dbg(&spi->dev,
"bits per word %d, chip select %d, speed %d KHz\n",
spi->bits_per_word, spi->chip_select,
(MCFQSPI_BUSCLK / mcfqspi_qmr_baud(spi->max_speed_hz))
/ 1000);
return 0;
}
static int mcfqspi_probe(struct platform_device *pdev)
{
struct spi_master *master;
struct mcfqspi *mcfqspi;
struct resource *res;
struct mcfqspi_platform_data *pdata;
int status;
pdata = dev_get_platdata(&pdev->dev);
if (!pdata) {
dev_dbg(&pdev->dev, "platform data is missing\n");
return -ENOENT;
}
if (!pdata->cs_control) {
dev_dbg(&pdev->dev, "pdata->cs_control is NULL\n");
return -EINVAL;
}
master = spi_alloc_master(&pdev->dev, sizeof(*mcfqspi));
if (master == NULL) {
dev_dbg(&pdev->dev, "spi_alloc_master failed\n");
return -ENOMEM;
}
mcfqspi = spi_master_get_devdata(master);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
mcfqspi->iobase = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(mcfqspi->iobase)) {
status = PTR_ERR(mcfqspi->iobase);
goto fail0;
}
mcfqspi->irq = platform_get_irq(pdev, 0);
if (mcfqspi->irq < 0) {
dev_dbg(&pdev->dev, "platform_get_irq failed\n");
status = -ENXIO;
goto fail0;
}
status = devm_request_irq(&pdev->dev, mcfqspi->irq, mcfqspi_irq_handler,
0, pdev->name, mcfqspi);
if (status) {
dev_dbg(&pdev->dev, "request_irq failed\n");
goto fail0;
}
mcfqspi->clk = devm_clk_get(&pdev->dev, "qspi_clk");
if (IS_ERR(mcfqspi->clk)) {
dev_dbg(&pdev->dev, "clk_get failed\n");
status = PTR_ERR(mcfqspi->clk);
goto fail0;
}
clk_enable(mcfqspi->clk);
master->bus_num = pdata->bus_num;
master->num_chipselect = pdata->num_chipselect;
mcfqspi->cs_control = pdata->cs_control;
status = mcfqspi_cs_setup(mcfqspi);
if (status) {
dev_dbg(&pdev->dev, "error initializing cs_control\n");
goto fail1;
}
init_waitqueue_head(&mcfqspi->waitq);
master->mode_bits = SPI_CS_HIGH | SPI_CPOL | SPI_CPHA;
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 16);
master->setup = mcfqspi_setup;
master->set_cs = mcfqspi_set_cs;
master->transfer_one = mcfqspi_transfer_one;
master->auto_runtime_pm = true;
platform_set_drvdata(pdev, master);
pm_runtime_enable(&pdev->dev);
status = devm_spi_register_master(&pdev->dev, master);
if (status) {
dev_dbg(&pdev->dev, "spi_register_master failed\n");
goto fail2;
}
dev_info(&pdev->dev, "Coldfire QSPI bus driver\n");
return 0;
fail2:
pm_runtime_disable(&pdev->dev);
mcfqspi_cs_teardown(mcfqspi);
fail1:
clk_disable(mcfqspi->clk);
fail0:
spi_master_put(master);
dev_dbg(&pdev->dev, "Coldfire QSPI probe failed\n");
return status;
}
static int mcfqspi_remove(struct platform_device *pdev)
{
struct spi_master *master = platform_get_drvdata(pdev);
struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
pm_runtime_disable(&pdev->dev);
/* disable the hardware (set the baud rate to 0) */
mcfqspi_wr_qmr(mcfqspi, MCFQSPI_QMR_MSTR);
mcfqspi_cs_teardown(mcfqspi);
clk_disable(mcfqspi->clk);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int mcfqspi_suspend(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
int ret;
ret = spi_master_suspend(master);
if (ret)
return ret;
clk_disable(mcfqspi->clk);
return 0;
}
static int mcfqspi_resume(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
clk_enable(mcfqspi->clk);
return spi_master_resume(master);
}
#endif
#ifdef CONFIG_PM
static int mcfqspi_runtime_suspend(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
clk_disable(mcfqspi->clk);
return 0;
}
static int mcfqspi_runtime_resume(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
clk_enable(mcfqspi->clk);
return 0;
}
#endif
static const struct dev_pm_ops mcfqspi_pm = {
SET_SYSTEM_SLEEP_PM_OPS(mcfqspi_suspend, mcfqspi_resume)
SET_RUNTIME_PM_OPS(mcfqspi_runtime_suspend, mcfqspi_runtime_resume,
NULL)
};
static struct platform_driver mcfqspi_driver = {
.driver.name = DRIVER_NAME,
.driver.owner = THIS_MODULE,
.driver.pm = &mcfqspi_pm,
.probe = mcfqspi_probe,
.remove = mcfqspi_remove,
};
module_platform_driver(mcfqspi_driver);
MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
MODULE_DESCRIPTION("Coldfire QSPI Controller Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRIVER_NAME);
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