linux/drivers/spi/spi-pxa2xx.c

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/*
* Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
* Copyright (C) 2013, Intel Corporation
*
* 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/bitops.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/ioport.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/spi/pxa2xx_spi.h>
#include <linux/spi/spi.h>
#include <linux/delay.h>
#include <linux/gpio.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/pm_runtime.h>
#include <linux/acpi.h>
#include "spi-pxa2xx.h"
MODULE_AUTHOR("Stephen Street");
MODULE_DESCRIPTION("PXA2xx SSP SPI Controller");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:pxa2xx-spi");
#define TIMOUT_DFLT 1000
/*
* for testing SSCR1 changes that require SSP restart, basically
* everything except the service and interrupt enables, the pxa270 developer
* manual says only SSCR1_SCFR, SSCR1_SPH, SSCR1_SPO need to be in this
* list, but the PXA255 dev man says all bits without really meaning the
* service and interrupt enables
*/
#define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
| SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
| SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
| SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
| SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \
| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
#define QUARK_X1000_SSCR1_CHANGE_MASK (QUARK_X1000_SSCR1_STRF \
| QUARK_X1000_SSCR1_EFWR \
| QUARK_X1000_SSCR1_RFT \
| QUARK_X1000_SSCR1_TFT \
| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
#define LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE BIT(24)
#define LPSS_CS_CONTROL_SW_MODE BIT(0)
#define LPSS_CS_CONTROL_CS_HIGH BIT(1)
#define LPSS_CAPS_CS_EN_SHIFT 9
#define LPSS_CAPS_CS_EN_MASK (0xf << LPSS_CAPS_CS_EN_SHIFT)
struct lpss_config {
/* LPSS offset from drv_data->ioaddr */
unsigned offset;
/* Register offsets from drv_data->lpss_base or -1 */
int reg_general;
int reg_ssp;
int reg_cs_ctrl;
int reg_capabilities;
/* FIFO thresholds */
u32 rx_threshold;
u32 tx_threshold_lo;
u32 tx_threshold_hi;
/* Chip select control */
unsigned cs_sel_shift;
unsigned cs_sel_mask;
unsigned cs_num;
};
/* Keep these sorted with enum pxa_ssp_type */
static const struct lpss_config lpss_platforms[] = {
{ /* LPSS_LPT_SSP */
.offset = 0x800,
.reg_general = 0x08,
.reg_ssp = 0x0c,
.reg_cs_ctrl = 0x18,
.reg_capabilities = -1,
.rx_threshold = 64,
.tx_threshold_lo = 160,
.tx_threshold_hi = 224,
},
{ /* LPSS_BYT_SSP */
.offset = 0x400,
.reg_general = 0x08,
.reg_ssp = 0x0c,
.reg_cs_ctrl = 0x18,
.reg_capabilities = -1,
.rx_threshold = 64,
.tx_threshold_lo = 160,
.tx_threshold_hi = 224,
},
{ /* LPSS_BSW_SSP */
.offset = 0x400,
.reg_general = 0x08,
.reg_ssp = 0x0c,
.reg_cs_ctrl = 0x18,
.reg_capabilities = -1,
.rx_threshold = 64,
.tx_threshold_lo = 160,
.tx_threshold_hi = 224,
.cs_sel_shift = 2,
.cs_sel_mask = 1 << 2,
.cs_num = 2,
},
{ /* LPSS_SPT_SSP */
.offset = 0x200,
.reg_general = -1,
.reg_ssp = 0x20,
.reg_cs_ctrl = 0x24,
.reg_capabilities = -1,
.rx_threshold = 1,
.tx_threshold_lo = 32,
.tx_threshold_hi = 56,
},
{ /* LPSS_BXT_SSP */
.offset = 0x200,
.reg_general = -1,
.reg_ssp = 0x20,
.reg_cs_ctrl = 0x24,
.reg_capabilities = 0xfc,
.rx_threshold = 1,
.tx_threshold_lo = 16,
.tx_threshold_hi = 48,
.cs_sel_shift = 8,
.cs_sel_mask = 3 << 8,
},
};
static inline const struct lpss_config
*lpss_get_config(const struct driver_data *drv_data)
{
return &lpss_platforms[drv_data->ssp_type - LPSS_LPT_SSP];
}
static bool is_lpss_ssp(const struct driver_data *drv_data)
{
switch (drv_data->ssp_type) {
case LPSS_LPT_SSP:
case LPSS_BYT_SSP:
case LPSS_BSW_SSP:
case LPSS_SPT_SSP:
case LPSS_BXT_SSP:
return true;
default:
return false;
}
}
static bool is_quark_x1000_ssp(const struct driver_data *drv_data)
{
return drv_data->ssp_type == QUARK_X1000_SSP;
}
static u32 pxa2xx_spi_get_ssrc1_change_mask(const struct driver_data *drv_data)
{
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
return QUARK_X1000_SSCR1_CHANGE_MASK;
default:
return SSCR1_CHANGE_MASK;
}
}
static u32
pxa2xx_spi_get_rx_default_thre(const struct driver_data *drv_data)
{
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
return RX_THRESH_QUARK_X1000_DFLT;
default:
return RX_THRESH_DFLT;
}
}
static bool pxa2xx_spi_txfifo_full(const struct driver_data *drv_data)
{
u32 mask;
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
mask = QUARK_X1000_SSSR_TFL_MASK;
break;
default:
mask = SSSR_TFL_MASK;
break;
}
return (pxa2xx_spi_read(drv_data, SSSR) & mask) == mask;
}
static void pxa2xx_spi_clear_rx_thre(const struct driver_data *drv_data,
u32 *sccr1_reg)
{
u32 mask;
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
mask = QUARK_X1000_SSCR1_RFT;
break;
default:
mask = SSCR1_RFT;
break;
}
*sccr1_reg &= ~mask;
}
static void pxa2xx_spi_set_rx_thre(const struct driver_data *drv_data,
u32 *sccr1_reg, u32 threshold)
{
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
*sccr1_reg |= QUARK_X1000_SSCR1_RxTresh(threshold);
break;
default:
*sccr1_reg |= SSCR1_RxTresh(threshold);
break;
}
}
static u32 pxa2xx_configure_sscr0(const struct driver_data *drv_data,
u32 clk_div, u8 bits)
{
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
return clk_div
| QUARK_X1000_SSCR0_Motorola
| QUARK_X1000_SSCR0_DataSize(bits > 32 ? 8 : bits)
| SSCR0_SSE;
default:
return clk_div
| SSCR0_Motorola
| SSCR0_DataSize(bits > 16 ? bits - 16 : bits)
| SSCR0_SSE
| (bits > 16 ? SSCR0_EDSS : 0);
}
}
/*
* Read and write LPSS SSP private registers. Caller must first check that
* is_lpss_ssp() returns true before these can be called.
*/
static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset)
{
WARN_ON(!drv_data->lpss_base);
return readl(drv_data->lpss_base + offset);
}
static void __lpss_ssp_write_priv(struct driver_data *drv_data,
unsigned offset, u32 value)
{
WARN_ON(!drv_data->lpss_base);
writel(value, drv_data->lpss_base + offset);
}
/*
* lpss_ssp_setup - perform LPSS SSP specific setup
* @drv_data: pointer to the driver private data
*
* Perform LPSS SSP specific setup. This function must be called first if
* one is going to use LPSS SSP private registers.
*/
static void lpss_ssp_setup(struct driver_data *drv_data)
{
const struct lpss_config *config;
u32 value;
config = lpss_get_config(drv_data);
drv_data->lpss_base = drv_data->ioaddr + config->offset;
/* Enable software chip select control */
value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
value &= ~(LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH);
value |= LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH;
__lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
/* Enable multiblock DMA transfers */
if (drv_data->master_info->enable_dma) {
__lpss_ssp_write_priv(drv_data, config->reg_ssp, 1);
if (config->reg_general >= 0) {
value = __lpss_ssp_read_priv(drv_data,
config->reg_general);
value |= LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE;
__lpss_ssp_write_priv(drv_data,
config->reg_general, value);
}
}
}
static void lpss_ssp_select_cs(struct driver_data *drv_data,
const struct lpss_config *config)
{
u32 value, cs;
if (!config->cs_sel_mask)
return;
value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
cs = drv_data->cur_msg->spi->chip_select;
cs <<= config->cs_sel_shift;
if (cs != (value & config->cs_sel_mask)) {
/*
* When switching another chip select output active the
* output must be selected first and wait 2 ssp_clk cycles
* before changing state to active. Otherwise a short
* glitch will occur on the previous chip select since
* output select is latched but state control is not.
*/
value &= ~config->cs_sel_mask;
value |= cs;
__lpss_ssp_write_priv(drv_data,
config->reg_cs_ctrl, value);
ndelay(1000000000 /
(drv_data->master->max_speed_hz / 2));
}
}
static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable)
{
const struct lpss_config *config;
u32 value;
config = lpss_get_config(drv_data);
if (enable)
lpss_ssp_select_cs(drv_data, config);
value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
if (enable)
value &= ~LPSS_CS_CONTROL_CS_HIGH;
else
value |= LPSS_CS_CONTROL_CS_HIGH;
__lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
}
static void cs_assert(struct driver_data *drv_data)
{
struct chip_data *chip = drv_data->cur_chip;
if (drv_data->ssp_type == CE4100_SSP) {
pxa2xx_spi_write(drv_data, SSSR, drv_data->cur_chip->frm);
return;
}
if (chip->cs_control) {
chip->cs_control(PXA2XX_CS_ASSERT);
return;
}
if (gpio_is_valid(chip->gpio_cs)) {
gpio_set_value(chip->gpio_cs, chip->gpio_cs_inverted);
return;
}
if (is_lpss_ssp(drv_data))
lpss_ssp_cs_control(drv_data, true);
}
static void cs_deassert(struct driver_data *drv_data)
{
struct chip_data *chip = drv_data->cur_chip;
if (drv_data->ssp_type == CE4100_SSP)
return;
if (chip->cs_control) {
chip->cs_control(PXA2XX_CS_DEASSERT);
return;
}
if (gpio_is_valid(chip->gpio_cs)) {
gpio_set_value(chip->gpio_cs, !chip->gpio_cs_inverted);
return;
}
if (is_lpss_ssp(drv_data))
lpss_ssp_cs_control(drv_data, false);
}
int pxa2xx_spi_flush(struct driver_data *drv_data)
{
unsigned long limit = loops_per_jiffy << 1;
do {
while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
pxa2xx_spi_read(drv_data, SSDR);
} while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY) && --limit);
write_SSSR_CS(drv_data, SSSR_ROR);
return limit;
}
static int null_writer(struct driver_data *drv_data)
{
u8 n_bytes = drv_data->n_bytes;
if (pxa2xx_spi_txfifo_full(drv_data)
|| (drv_data->tx == drv_data->tx_end))
return 0;
pxa2xx_spi_write(drv_data, SSDR, 0);
drv_data->tx += n_bytes;
return 1;
}
static int null_reader(struct driver_data *drv_data)
{
u8 n_bytes = drv_data->n_bytes;
while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
&& (drv_data->rx < drv_data->rx_end)) {
pxa2xx_spi_read(drv_data, SSDR);
drv_data->rx += n_bytes;
}
return drv_data->rx == drv_data->rx_end;
}
static int u8_writer(struct driver_data *drv_data)
{
if (pxa2xx_spi_txfifo_full(drv_data)
|| (drv_data->tx == drv_data->tx_end))
return 0;
pxa2xx_spi_write(drv_data, SSDR, *(u8 *)(drv_data->tx));
++drv_data->tx;
return 1;
}
static int u8_reader(struct driver_data *drv_data)
{
while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
&& (drv_data->rx < drv_data->rx_end)) {
*(u8 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
++drv_data->rx;
}
return drv_data->rx == drv_data->rx_end;
}
static int u16_writer(struct driver_data *drv_data)
{
if (pxa2xx_spi_txfifo_full(drv_data)
|| (drv_data->tx == drv_data->tx_end))
return 0;
pxa2xx_spi_write(drv_data, SSDR, *(u16 *)(drv_data->tx));
drv_data->tx += 2;
return 1;
}
static int u16_reader(struct driver_data *drv_data)
{
while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
&& (drv_data->rx < drv_data->rx_end)) {
*(u16 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
drv_data->rx += 2;
}
return drv_data->rx == drv_data->rx_end;
}
static int u32_writer(struct driver_data *drv_data)
{
if (pxa2xx_spi_txfifo_full(drv_data)
|| (drv_data->tx == drv_data->tx_end))
return 0;
pxa2xx_spi_write(drv_data, SSDR, *(u32 *)(drv_data->tx));
drv_data->tx += 4;
return 1;
}
static int u32_reader(struct driver_data *drv_data)
{
while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
&& (drv_data->rx < drv_data->rx_end)) {
*(u32 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
drv_data->rx += 4;
}
return drv_data->rx == drv_data->rx_end;
}
void *pxa2xx_spi_next_transfer(struct driver_data *drv_data)
{
struct spi_message *msg = drv_data->cur_msg;
struct spi_transfer *trans = drv_data->cur_transfer;
/* Move to next transfer */
if (trans->transfer_list.next != &msg->transfers) {
drv_data->cur_transfer =
list_entry(trans->transfer_list.next,
struct spi_transfer,
transfer_list);
return RUNNING_STATE;
} else
return DONE_STATE;
}
/* caller already set message->status; dma and pio irqs are blocked */
static void giveback(struct driver_data *drv_data)
{
struct spi_transfer* last_transfer;
struct spi_message *msg;
unsigned long timeout;
msg = drv_data->cur_msg;
drv_data->cur_msg = NULL;
drv_data->cur_transfer = NULL;
last_transfer = list_last_entry(&msg->transfers, struct spi_transfer,
transfer_list);
pxa2xx_spi: chipselect bugfixes Fixes several chipselect bugs in the pxa2xx_spi driver. These bugs are in all versions of this driver and prevent using it with chips like m25p16 flash. 1. The spi_transfer.cs_change flag is handled too early: before spi_transfer.delay_usecs applies, thus making the delay ineffective at holding chip select. 2. spi_transfer.delay_usecs is ignored on the last transfer of a message (likewise not holding chipselect long enough). 3. If spi_transfer.cs_change is set on the last transfer, the chip select is always disabled, instead of the intended meaning: optionally holding chip select enabled for the next message. Those first three bugs were fixed with a relocation of delays and chip select de-assertions. 4. If a message has the cs_change flag set on the last transfer, and had the chip select stayed enabled as requested (see 3, above), it would not have been disabled if the next message is for a different chip. Fixed by dropping chip select regardless of cs_change at end of a message, if there is no next message or if the next message is for a different chip. This patch should apply to all kernels back to and including 2.6.20; it was test patched against 2.6.20. An additional patch would be required for older kernels, but those versions are very buggy anyway. Signed-off-by: Ned Forrester <nforrester@whoi.edu> Cc: Vernon Sauder <vernoninhand@gmail.com> Cc: Eric Miao <eric.y.miao@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-13 09:33:17 +00:00
/* Delay if requested before any change in chip select */
if (last_transfer->delay_usecs)
udelay(last_transfer->delay_usecs);
/* Wait until SSP becomes idle before deasserting the CS */
timeout = jiffies + msecs_to_jiffies(10);
while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY &&
!time_after(jiffies, timeout))
cpu_relax();
pxa2xx_spi: chipselect bugfixes Fixes several chipselect bugs in the pxa2xx_spi driver. These bugs are in all versions of this driver and prevent using it with chips like m25p16 flash. 1. The spi_transfer.cs_change flag is handled too early: before spi_transfer.delay_usecs applies, thus making the delay ineffective at holding chip select. 2. spi_transfer.delay_usecs is ignored on the last transfer of a message (likewise not holding chipselect long enough). 3. If spi_transfer.cs_change is set on the last transfer, the chip select is always disabled, instead of the intended meaning: optionally holding chip select enabled for the next message. Those first three bugs were fixed with a relocation of delays and chip select de-assertions. 4. If a message has the cs_change flag set on the last transfer, and had the chip select stayed enabled as requested (see 3, above), it would not have been disabled if the next message is for a different chip. Fixed by dropping chip select regardless of cs_change at end of a message, if there is no next message or if the next message is for a different chip. This patch should apply to all kernels back to and including 2.6.20; it was test patched against 2.6.20. An additional patch would be required for older kernels, but those versions are very buggy anyway. Signed-off-by: Ned Forrester <nforrester@whoi.edu> Cc: Vernon Sauder <vernoninhand@gmail.com> Cc: Eric Miao <eric.y.miao@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-13 09:33:17 +00:00
/* Drop chip select UNLESS cs_change is true or we are returning
* a message with an error, or next message is for another chip
*/
if (!last_transfer->cs_change)
cs_deassert(drv_data);
pxa2xx_spi: chipselect bugfixes Fixes several chipselect bugs in the pxa2xx_spi driver. These bugs are in all versions of this driver and prevent using it with chips like m25p16 flash. 1. The spi_transfer.cs_change flag is handled too early: before spi_transfer.delay_usecs applies, thus making the delay ineffective at holding chip select. 2. spi_transfer.delay_usecs is ignored on the last transfer of a message (likewise not holding chipselect long enough). 3. If spi_transfer.cs_change is set on the last transfer, the chip select is always disabled, instead of the intended meaning: optionally holding chip select enabled for the next message. Those first three bugs were fixed with a relocation of delays and chip select de-assertions. 4. If a message has the cs_change flag set on the last transfer, and had the chip select stayed enabled as requested (see 3, above), it would not have been disabled if the next message is for a different chip. Fixed by dropping chip select regardless of cs_change at end of a message, if there is no next message or if the next message is for a different chip. This patch should apply to all kernels back to and including 2.6.20; it was test patched against 2.6.20. An additional patch would be required for older kernels, but those versions are very buggy anyway. Signed-off-by: Ned Forrester <nforrester@whoi.edu> Cc: Vernon Sauder <vernoninhand@gmail.com> Cc: Eric Miao <eric.y.miao@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-13 09:33:17 +00:00
else {
struct spi_message *next_msg;
/* Holding of cs was hinted, but we need to make sure
* the next message is for the same chip. Don't waste
* time with the following tests unless this was hinted.
*
* We cannot postpone this until pump_messages, because
* after calling msg->complete (below) the driver that
* sent the current message could be unloaded, which
* could invalidate the cs_control() callback...
*/
/* get a pointer to the next message, if any */
next_msg = spi_get_next_queued_message(drv_data->master);
pxa2xx_spi: chipselect bugfixes Fixes several chipselect bugs in the pxa2xx_spi driver. These bugs are in all versions of this driver and prevent using it with chips like m25p16 flash. 1. The spi_transfer.cs_change flag is handled too early: before spi_transfer.delay_usecs applies, thus making the delay ineffective at holding chip select. 2. spi_transfer.delay_usecs is ignored on the last transfer of a message (likewise not holding chipselect long enough). 3. If spi_transfer.cs_change is set on the last transfer, the chip select is always disabled, instead of the intended meaning: optionally holding chip select enabled for the next message. Those first three bugs were fixed with a relocation of delays and chip select de-assertions. 4. If a message has the cs_change flag set on the last transfer, and had the chip select stayed enabled as requested (see 3, above), it would not have been disabled if the next message is for a different chip. Fixed by dropping chip select regardless of cs_change at end of a message, if there is no next message or if the next message is for a different chip. This patch should apply to all kernels back to and including 2.6.20; it was test patched against 2.6.20. An additional patch would be required for older kernels, but those versions are very buggy anyway. Signed-off-by: Ned Forrester <nforrester@whoi.edu> Cc: Vernon Sauder <vernoninhand@gmail.com> Cc: Eric Miao <eric.y.miao@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-13 09:33:17 +00:00
/* see if the next and current messages point
* to the same chip
*/
if ((next_msg && next_msg->spi != msg->spi) ||
msg->state == ERROR_STATE)
cs_deassert(drv_data);
pxa2xx_spi: chipselect bugfixes Fixes several chipselect bugs in the pxa2xx_spi driver. These bugs are in all versions of this driver and prevent using it with chips like m25p16 flash. 1. The spi_transfer.cs_change flag is handled too early: before spi_transfer.delay_usecs applies, thus making the delay ineffective at holding chip select. 2. spi_transfer.delay_usecs is ignored on the last transfer of a message (likewise not holding chipselect long enough). 3. If spi_transfer.cs_change is set on the last transfer, the chip select is always disabled, instead of the intended meaning: optionally holding chip select enabled for the next message. Those first three bugs were fixed with a relocation of delays and chip select de-assertions. 4. If a message has the cs_change flag set on the last transfer, and had the chip select stayed enabled as requested (see 3, above), it would not have been disabled if the next message is for a different chip. Fixed by dropping chip select regardless of cs_change at end of a message, if there is no next message or if the next message is for a different chip. This patch should apply to all kernels back to and including 2.6.20; it was test patched against 2.6.20. An additional patch would be required for older kernels, but those versions are very buggy anyway. Signed-off-by: Ned Forrester <nforrester@whoi.edu> Cc: Vernon Sauder <vernoninhand@gmail.com> Cc: Eric Miao <eric.y.miao@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-13 09:33:17 +00:00
}
drv_data->cur_chip = NULL;
spi/pxa2xx: Clear cur_chip pointer before starting next message Once the current message is finished, the driver notifies SPI core about this by calling spi_finalize_current_message(). This function queues next message to be transferred. If there are more messages in the queue, it is possible that the driver is asked to transfer the next message at this point. When spi_finalize_current_message() returns the driver clears the drv_data->cur_chip pointer to NULL. The problem is that if the driver already started the next message clearing drv_data->cur_chip will cause NULL pointer dereference which crashes the kernel like: BUG: unable to handle kernel NULL pointer dereference at 0000000000000048 IP: [<ffffffffa0022bc8>] cs_deassert+0x18/0x70 [spi_pxa2xx_platform] PGD 78bb8067 PUD 37712067 PMD 0 Oops: 0000 [#1] SMP Modules linked in: CPU: 1 PID: 11 Comm: ksoftirqd/1 Tainted: G O 3.18.0-rc4-mjo #5 Hardware name: Intel Corp. VALLEYVIEW B3 PLATFORM/NOTEBOOK, BIOS MNW2CRB1.X64.0071.R30.1408131301 08/13/2014 task: ffff880077f9f290 ti: ffff88007a820000 task.ti: ffff88007a820000 RIP: 0010:[<ffffffffa0022bc8>] [<ffffffffa0022bc8>] cs_deassert+0x18/0x70 [spi_pxa2xx_platform] RSP: 0018:ffff88007a823d08 EFLAGS: 00010202 RAX: 0000000000000008 RBX: ffff8800379a4430 RCX: 0000000000000026 RDX: 0000000000000000 RSI: 0000000000000246 RDI: ffff8800379a4430 RBP: ffff88007a823d18 R08: 00000000ffffffff R09: 000000007a9bc65a R10: 000000000000028f R11: 0000000000000005 R12: ffff880070123e98 R13: ffff880070123de8 R14: 0000000000000100 R15: ffffc90004888000 FS: 0000000000000000(0000) GS:ffff880079a80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000048 CR3: 000000007029b000 CR4: 00000000001007e0 Stack: ffff88007a823d58 ffff8800379a4430 ffff88007a823d48 ffffffffa0022c89 0000000000000000 ffff8800379a4430 0000000000000000 0000000000000006 ffff88007a823da8 ffffffffa0023be0 ffff88007a823dd8 ffffffff81076204 Call Trace: [<ffffffffa0022c89>] giveback+0x69/0xa0 [spi_pxa2xx_platform] [<ffffffffa0023be0>] pump_transfers+0x710/0x740 [spi_pxa2xx_platform] [<ffffffff81076204>] ? pick_next_task_fair+0x744/0x830 [<ffffffff81049679>] tasklet_action+0xa9/0xe0 [<ffffffff81049a0e>] __do_softirq+0xee/0x280 [<ffffffff81049bc0>] run_ksoftirqd+0x20/0x40 [<ffffffff810646df>] smpboot_thread_fn+0xff/0x1b0 [<ffffffff810645e0>] ? SyS_setgroups+0x150/0x150 [<ffffffff81060f9d>] kthread+0xcd/0xf0 [<ffffffff81060ed0>] ? kthread_create_on_node+0x180/0x180 [<ffffffff8187a82c>] ret_from_fork+0x7c/0xb0 Fix this by clearing drv_data->cur_chip before we call spi_finalize_current_message(). Reported-by: Martin Oldfield <m@mjoldfield.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org
2014-12-29 08:33:36 +00:00
spi_finalize_current_message(drv_data->master);
}
static void reset_sccr1(struct driver_data *drv_data)
{
struct chip_data *chip = drv_data->cur_chip;
u32 sccr1_reg;
sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1;
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
sccr1_reg &= ~QUARK_X1000_SSCR1_RFT;
break;
default:
sccr1_reg &= ~SSCR1_RFT;
break;
}
sccr1_reg |= chip->threshold;
pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
}
static void int_error_stop(struct driver_data *drv_data, const char* msg)
{
/* Stop and reset SSP */
write_SSSR_CS(drv_data, drv_data->clear_sr);
reset_sccr1(drv_data);
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, 0);
pxa2xx_spi_flush(drv_data);
pxa2xx_spi_write(drv_data, SSCR0,
pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
dev_err(&drv_data->pdev->dev, "%s\n", msg);
drv_data->cur_msg->state = ERROR_STATE;
tasklet_schedule(&drv_data->pump_transfers);
}
static void int_transfer_complete(struct driver_data *drv_data)
{
/* Clear and disable interrupts */
write_SSSR_CS(drv_data, drv_data->clear_sr);
reset_sccr1(drv_data);
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, 0);
/* Update total byte transferred return count actual bytes read */
drv_data->cur_msg->actual_length += drv_data->len -
(drv_data->rx_end - drv_data->rx);
pxa2xx_spi: chipselect bugfixes Fixes several chipselect bugs in the pxa2xx_spi driver. These bugs are in all versions of this driver and prevent using it with chips like m25p16 flash. 1. The spi_transfer.cs_change flag is handled too early: before spi_transfer.delay_usecs applies, thus making the delay ineffective at holding chip select. 2. spi_transfer.delay_usecs is ignored on the last transfer of a message (likewise not holding chipselect long enough). 3. If spi_transfer.cs_change is set on the last transfer, the chip select is always disabled, instead of the intended meaning: optionally holding chip select enabled for the next message. Those first three bugs were fixed with a relocation of delays and chip select de-assertions. 4. If a message has the cs_change flag set on the last transfer, and had the chip select stayed enabled as requested (see 3, above), it would not have been disabled if the next message is for a different chip. Fixed by dropping chip select regardless of cs_change at end of a message, if there is no next message or if the next message is for a different chip. This patch should apply to all kernels back to and including 2.6.20; it was test patched against 2.6.20. An additional patch would be required for older kernels, but those versions are very buggy anyway. Signed-off-by: Ned Forrester <nforrester@whoi.edu> Cc: Vernon Sauder <vernoninhand@gmail.com> Cc: Eric Miao <eric.y.miao@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-13 09:33:17 +00:00
/* Transfer delays and chip select release are
* handled in pump_transfers or giveback
*/
/* Move to next transfer */
drv_data->cur_msg->state = pxa2xx_spi_next_transfer(drv_data);
/* Schedule transfer tasklet */
tasklet_schedule(&drv_data->pump_transfers);
}
static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
{
u32 irq_mask = (pxa2xx_spi_read(drv_data, SSCR1) & SSCR1_TIE) ?
drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;
u32 irq_status = pxa2xx_spi_read(drv_data, SSSR) & irq_mask;
if (irq_status & SSSR_ROR) {
int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
return IRQ_HANDLED;
}
if (irq_status & SSSR_TINT) {
pxa2xx_spi_write(drv_data, SSSR, SSSR_TINT);
if (drv_data->read(drv_data)) {
int_transfer_complete(drv_data);
return IRQ_HANDLED;
}
}
/* Drain rx fifo, Fill tx fifo and prevent overruns */
do {
if (drv_data->read(drv_data)) {
int_transfer_complete(drv_data);
return IRQ_HANDLED;
}
} while (drv_data->write(drv_data));
if (drv_data->read(drv_data)) {
int_transfer_complete(drv_data);
return IRQ_HANDLED;
}
if (drv_data->tx == drv_data->tx_end) {
u32 bytes_left;
u32 sccr1_reg;
sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
sccr1_reg &= ~SSCR1_TIE;
/*
* PXA25x_SSP has no timeout, set up rx threshould for the
* remaining RX bytes.
*/
if (pxa25x_ssp_comp(drv_data)) {
u32 rx_thre;
pxa2xx_spi_clear_rx_thre(drv_data, &sccr1_reg);
bytes_left = drv_data->rx_end - drv_data->rx;
switch (drv_data->n_bytes) {
case 4:
bytes_left >>= 1;
case 2:
bytes_left >>= 1;
}
rx_thre = pxa2xx_spi_get_rx_default_thre(drv_data);
if (rx_thre > bytes_left)
rx_thre = bytes_left;
pxa2xx_spi_set_rx_thre(drv_data, &sccr1_reg, rx_thre);
}
pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
}
/* We did something */
return IRQ_HANDLED;
}
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 13:55:46 +00:00
static irqreturn_t ssp_int(int irq, void *dev_id)
{
struct driver_data *drv_data = dev_id;
u32 sccr1_reg;
u32 mask = drv_data->mask_sr;
u32 status;
/*
* The IRQ might be shared with other peripherals so we must first
* check that are we RPM suspended or not. If we are we assume that
* the IRQ was not for us (we shouldn't be RPM suspended when the
* interrupt is enabled).
*/
if (pm_runtime_suspended(&drv_data->pdev->dev))
return IRQ_NONE;
/*
* If the device is not yet in RPM suspended state and we get an
* interrupt that is meant for another device, check if status bits
* are all set to one. That means that the device is already
* powered off.
*/
status = pxa2xx_spi_read(drv_data, SSSR);
if (status == ~0)
return IRQ_NONE;
sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
/* Ignore possible writes if we don't need to write */
if (!(sccr1_reg & SSCR1_TIE))
mask &= ~SSSR_TFS;
/* Ignore RX timeout interrupt if it is disabled */
if (!(sccr1_reg & SSCR1_TINTE))
mask &= ~SSSR_TINT;
if (!(status & mask))
return IRQ_NONE;
if (!drv_data->cur_msg) {
pxa2xx_spi_write(drv_data, SSCR0,
pxa2xx_spi_read(drv_data, SSCR0)
& ~SSCR0_SSE);
pxa2xx_spi_write(drv_data, SSCR1,
pxa2xx_spi_read(drv_data, SSCR1)
& ~drv_data->int_cr1);
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, 0);
write_SSSR_CS(drv_data, drv_data->clear_sr);
dev_err(&drv_data->pdev->dev,
"bad message state in interrupt handler\n");
/* Never fail */
return IRQ_HANDLED;
}
return drv_data->transfer_handler(drv_data);
}
/*
* The Quark SPI has an additional 24 bit register (DDS_CLK_RATE) to multiply
* input frequency by fractions of 2^24. It also has a divider by 5.
*
* There are formulas to get baud rate value for given input frequency and
* divider parameters, such as DDS_CLK_RATE and SCR:
*
* Fsys = 200MHz
*
* Fssp = Fsys * DDS_CLK_RATE / 2^24 (1)
* Baud rate = Fsclk = Fssp / (2 * (SCR + 1)) (2)
*
* DDS_CLK_RATE either 2^n or 2^n / 5.
* SCR is in range 0 .. 255
*
* Divisor = 5^i * 2^j * 2 * k
* i = [0, 1] i = 1 iff j = 0 or j > 3
* j = [0, 23] j = 0 iff i = 1
* k = [1, 256]
* Special case: j = 0, i = 1: Divisor = 2 / 5
*
* Accordingly to the specification the recommended values for DDS_CLK_RATE
* are:
* Case 1: 2^n, n = [0, 23]
* Case 2: 2^24 * 2 / 5 (0x666666)
* Case 3: less than or equal to 2^24 / 5 / 16 (0x33333)
*
* In all cases the lowest possible value is better.
*
* The function calculates parameters for all cases and chooses the one closest
* to the asked baud rate.
*/
static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
{
unsigned long xtal = 200000000;
unsigned long fref = xtal / 2; /* mandatory division by 2,
see (2) */
/* case 3 */
unsigned long fref1 = fref / 2; /* case 1 */
unsigned long fref2 = fref * 2 / 5; /* case 2 */
unsigned long scale;
unsigned long q, q1, q2;
long r, r1, r2;
u32 mul;
/* Case 1 */
/* Set initial value for DDS_CLK_RATE */
mul = (1 << 24) >> 1;
/* Calculate initial quot */
q1 = DIV_ROUND_UP(fref1, rate);
/* Scale q1 if it's too big */
if (q1 > 256) {
/* Scale q1 to range [1, 512] */
scale = fls_long(q1 - 1);
if (scale > 9) {
q1 >>= scale - 9;
mul >>= scale - 9;
}
/* Round the result if we have a remainder */
q1 += q1 & 1;
}
/* Decrease DDS_CLK_RATE as much as we can without loss in precision */
scale = __ffs(q1);
q1 >>= scale;
mul >>= scale;
/* Get the remainder */
r1 = abs(fref1 / (1 << (24 - fls_long(mul))) / q1 - rate);
/* Case 2 */
q2 = DIV_ROUND_UP(fref2, rate);
r2 = abs(fref2 / q2 - rate);
/*
* Choose the best between two: less remainder we have the better. We
* can't go case 2 if q2 is greater than 256 since SCR register can
* hold only values 0 .. 255.
*/
if (r2 >= r1 || q2 > 256) {
/* case 1 is better */
r = r1;
q = q1;
} else {
/* case 2 is better */
r = r2;
q = q2;
mul = (1 << 24) * 2 / 5;
}
/* Check case 3 only if the divisor is big enough */
if (fref / rate >= 80) {
u64 fssp;
u32 m;
/* Calculate initial quot */
q1 = DIV_ROUND_UP(fref, rate);
m = (1 << 24) / q1;
/* Get the remainder */
fssp = (u64)fref * m;
do_div(fssp, 1 << 24);
r1 = abs(fssp - rate);
/* Choose this one if it suits better */
if (r1 < r) {
/* case 3 is better */
q = 1;
mul = m;
}
}
*dds = mul;
return q - 1;
}
static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
{
unsigned long ssp_clk = drv_data->master->max_speed_hz;
const struct ssp_device *ssp = drv_data->ssp;
rate = min_t(int, ssp_clk, rate);
if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP)
return (ssp_clk / (2 * rate) - 1) & 0xff;
else
return (ssp_clk / rate - 1) & 0xfff;
}
static unsigned int pxa2xx_ssp_get_clk_div(struct driver_data *drv_data,
int rate)
{
struct chip_data *chip = drv_data->cur_chip;
unsigned int clk_div;
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
clk_div = quark_x1000_get_clk_div(rate, &chip->dds_rate);
break;
default:
clk_div = ssp_get_clk_div(drv_data, rate);
break;
}
return clk_div << 8;
}
static bool pxa2xx_spi_can_dma(struct spi_master *master,
struct spi_device *spi,
struct spi_transfer *xfer)
{
struct chip_data *chip = spi_get_ctldata(spi);
return chip->enable_dma &&
xfer->len <= MAX_DMA_LEN &&
xfer->len >= chip->dma_burst_size;
}
static void pump_transfers(unsigned long data)
{
struct driver_data *drv_data = (struct driver_data *)data;
struct spi_master *master = drv_data->master;
struct spi_message *message = NULL;
struct spi_transfer *transfer = NULL;
struct spi_transfer *previous = NULL;
struct chip_data *chip = NULL;
u32 clk_div = 0;
u8 bits = 0;
u32 speed = 0;
u32 cr0;
u32 cr1;
u32 dma_thresh = drv_data->cur_chip->dma_threshold;
u32 dma_burst = drv_data->cur_chip->dma_burst_size;
u32 change_mask = pxa2xx_spi_get_ssrc1_change_mask(drv_data);
int err;
int dma_mapped;
/* Get current state information */
message = drv_data->cur_msg;
transfer = drv_data->cur_transfer;
chip = drv_data->cur_chip;
/* Handle for abort */
if (message->state == ERROR_STATE) {
message->status = -EIO;
giveback(drv_data);
return;
}
/* Handle end of message */
if (message->state == DONE_STATE) {
message->status = 0;
giveback(drv_data);
return;
}
pxa2xx_spi: chipselect bugfixes Fixes several chipselect bugs in the pxa2xx_spi driver. These bugs are in all versions of this driver and prevent using it with chips like m25p16 flash. 1. The spi_transfer.cs_change flag is handled too early: before spi_transfer.delay_usecs applies, thus making the delay ineffective at holding chip select. 2. spi_transfer.delay_usecs is ignored on the last transfer of a message (likewise not holding chipselect long enough). 3. If spi_transfer.cs_change is set on the last transfer, the chip select is always disabled, instead of the intended meaning: optionally holding chip select enabled for the next message. Those first three bugs were fixed with a relocation of delays and chip select de-assertions. 4. If a message has the cs_change flag set on the last transfer, and had the chip select stayed enabled as requested (see 3, above), it would not have been disabled if the next message is for a different chip. Fixed by dropping chip select regardless of cs_change at end of a message, if there is no next message or if the next message is for a different chip. This patch should apply to all kernels back to and including 2.6.20; it was test patched against 2.6.20. An additional patch would be required for older kernels, but those versions are very buggy anyway. Signed-off-by: Ned Forrester <nforrester@whoi.edu> Cc: Vernon Sauder <vernoninhand@gmail.com> Cc: Eric Miao <eric.y.miao@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-13 09:33:17 +00:00
/* Delay if requested at end of transfer before CS change */
if (message->state == RUNNING_STATE) {
previous = list_entry(transfer->transfer_list.prev,
struct spi_transfer,
transfer_list);
if (previous->delay_usecs)
udelay(previous->delay_usecs);
pxa2xx_spi: chipselect bugfixes Fixes several chipselect bugs in the pxa2xx_spi driver. These bugs are in all versions of this driver and prevent using it with chips like m25p16 flash. 1. The spi_transfer.cs_change flag is handled too early: before spi_transfer.delay_usecs applies, thus making the delay ineffective at holding chip select. 2. spi_transfer.delay_usecs is ignored on the last transfer of a message (likewise not holding chipselect long enough). 3. If spi_transfer.cs_change is set on the last transfer, the chip select is always disabled, instead of the intended meaning: optionally holding chip select enabled for the next message. Those first three bugs were fixed with a relocation of delays and chip select de-assertions. 4. If a message has the cs_change flag set on the last transfer, and had the chip select stayed enabled as requested (see 3, above), it would not have been disabled if the next message is for a different chip. Fixed by dropping chip select regardless of cs_change at end of a message, if there is no next message or if the next message is for a different chip. This patch should apply to all kernels back to and including 2.6.20; it was test patched against 2.6.20. An additional patch would be required for older kernels, but those versions are very buggy anyway. Signed-off-by: Ned Forrester <nforrester@whoi.edu> Cc: Vernon Sauder <vernoninhand@gmail.com> Cc: Eric Miao <eric.y.miao@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-13 09:33:17 +00:00
/* Drop chip select only if cs_change is requested */
if (previous->cs_change)
cs_deassert(drv_data);
}
/* Check if we can DMA this transfer */
if (transfer->len > MAX_DMA_LEN && chip->enable_dma) {
/* reject already-mapped transfers; PIO won't always work */
if (message->is_dma_mapped
|| transfer->rx_dma || transfer->tx_dma) {
dev_err(&drv_data->pdev->dev,
"pump_transfers: mapped transfer length of "
"%u is greater than %d\n",
transfer->len, MAX_DMA_LEN);
message->status = -EINVAL;
giveback(drv_data);
return;
}
/* warn ... we force this to PIO mode */
dev_warn_ratelimited(&message->spi->dev,
"pump_transfers: DMA disabled for transfer length %ld "
"greater than %d\n",
(long)drv_data->len, MAX_DMA_LEN);
}
/* Setup the transfer state based on the type of transfer */
if (pxa2xx_spi_flush(drv_data) == 0) {
dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
message->status = -EIO;
giveback(drv_data);
return;
}
drv_data->n_bytes = chip->n_bytes;
drv_data->tx = (void *)transfer->tx_buf;
drv_data->tx_end = drv_data->tx + transfer->len;
drv_data->rx = transfer->rx_buf;
drv_data->rx_end = drv_data->rx + transfer->len;
drv_data->len = transfer->len;
drv_data->write = drv_data->tx ? chip->write : null_writer;
drv_data->read = drv_data->rx ? chip->read : null_reader;
/* Change speed and bit per word on a per transfer */
bits = transfer->bits_per_word;
speed = transfer->speed_hz;
clk_div = pxa2xx_ssp_get_clk_div(drv_data, speed);
if (bits <= 8) {
drv_data->n_bytes = 1;
drv_data->read = drv_data->read != null_reader ?
u8_reader : null_reader;
drv_data->write = drv_data->write != null_writer ?
u8_writer : null_writer;
} else if (bits <= 16) {
drv_data->n_bytes = 2;
drv_data->read = drv_data->read != null_reader ?
u16_reader : null_reader;
drv_data->write = drv_data->write != null_writer ?
u16_writer : null_writer;
} else if (bits <= 32) {
drv_data->n_bytes = 4;
drv_data->read = drv_data->read != null_reader ?
u32_reader : null_reader;
drv_data->write = drv_data->write != null_writer ?
u32_writer : null_writer;
}
/*
* if bits/word is changed in dma mode, then must check the
* thresholds and burst also
*/
if (chip->enable_dma) {
if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
message->spi,
bits, &dma_burst,
&dma_thresh))
dev_warn_ratelimited(&message->spi->dev,
"pump_transfers: DMA burst size reduced to match bits_per_word\n");
}
message->state = RUNNING_STATE;
dma_mapped = master->can_dma &&
master->can_dma(master, message->spi, transfer) &&
master->cur_msg_mapped;
if (dma_mapped) {
/* Ensure we have the correct interrupt handler */
drv_data->transfer_handler = pxa2xx_spi_dma_transfer;
err = pxa2xx_spi_dma_prepare(drv_data, dma_burst);
if (err) {
message->status = err;
giveback(drv_data);
return;
}
/* Clear status and start DMA engine */
cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
pxa2xx_spi_write(drv_data, SSSR, drv_data->clear_sr);
pxa2xx_spi_dma_start(drv_data);
} else {
/* Ensure we have the correct interrupt handler */
drv_data->transfer_handler = interrupt_transfer;
/* Clear status */
cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1;
write_SSSR_CS(drv_data, drv_data->clear_sr);
}
/* NOTE: PXA25x_SSP _could_ use external clocking ... */
cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits);
if (!pxa25x_ssp_comp(drv_data))
dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
master->max_speed_hz
/ (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)),
dma_mapped ? "DMA" : "PIO");
else
dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
master->max_speed_hz / 2
/ (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)),
dma_mapped ? "DMA" : "PIO");
if (is_lpss_ssp(drv_data)) {
if ((pxa2xx_spi_read(drv_data, SSIRF) & 0xff)
!= chip->lpss_rx_threshold)
pxa2xx_spi_write(drv_data, SSIRF,
chip->lpss_rx_threshold);
if ((pxa2xx_spi_read(drv_data, SSITF) & 0xffff)
!= chip->lpss_tx_threshold)
pxa2xx_spi_write(drv_data, SSITF,
chip->lpss_tx_threshold);
}
if (is_quark_x1000_ssp(drv_data) &&
(pxa2xx_spi_read(drv_data, DDS_RATE) != chip->dds_rate))
pxa2xx_spi_write(drv_data, DDS_RATE, chip->dds_rate);
/* see if we need to reload the config registers */
if ((pxa2xx_spi_read(drv_data, SSCR0) != cr0)
|| (pxa2xx_spi_read(drv_data, SSCR1) & change_mask)
!= (cr1 & change_mask)) {
/* stop the SSP, and update the other bits */
pxa2xx_spi_write(drv_data, SSCR0, cr0 & ~SSCR0_SSE);
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
/* first set CR1 without interrupt and service enables */
pxa2xx_spi_write(drv_data, SSCR1, cr1 & change_mask);
/* restart the SSP */
pxa2xx_spi_write(drv_data, SSCR0, cr0);
} else {
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
}
cs_assert(drv_data);
/* after chip select, release the data by enabling service
* requests and interrupts, without changing any mode bits */
pxa2xx_spi_write(drv_data, SSCR1, cr1);
}
static int pxa2xx_spi_transfer_one_message(struct spi_master *master,
struct spi_message *msg)
{
struct driver_data *drv_data = spi_master_get_devdata(master);
drv_data->cur_msg = msg;
/* Initial message state*/
drv_data->cur_msg->state = START_STATE;
drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
struct spi_transfer,
transfer_list);
/* prepare to setup the SSP, in pump_transfers, using the per
* chip configuration */
drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
/* Mark as busy and launch transfers */
tasklet_schedule(&drv_data->pump_transfers);
return 0;
}
static int pxa2xx_spi_unprepare_transfer(struct spi_master *master)
{
struct driver_data *drv_data = spi_master_get_devdata(master);
/* Disable the SSP now */
pxa2xx_spi_write(drv_data, SSCR0,
pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
return 0;
}
static int setup_cs(struct spi_device *spi, struct chip_data *chip,
struct pxa2xx_spi_chip *chip_info)
{
int err = 0;
if (chip == NULL || chip_info == NULL)
return 0;
/* NOTE: setup() can be called multiple times, possibly with
* different chip_info, release previously requested GPIO
*/
if (gpio_is_valid(chip->gpio_cs))
gpio_free(chip->gpio_cs);
/* If (*cs_control) is provided, ignore GPIO chip select */
if (chip_info->cs_control) {
chip->cs_control = chip_info->cs_control;
return 0;
}
if (gpio_is_valid(chip_info->gpio_cs)) {
err = gpio_request(chip_info->gpio_cs, "SPI_CS");
if (err) {
dev_err(&spi->dev, "failed to request chip select GPIO%d\n",
chip_info->gpio_cs);
return err;
}
chip->gpio_cs = chip_info->gpio_cs;
chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
err = gpio_direction_output(chip->gpio_cs,
!chip->gpio_cs_inverted);
}
return err;
}
static int setup(struct spi_device *spi)
{
struct pxa2xx_spi_chip *chip_info = NULL;
struct chip_data *chip;
const struct lpss_config *config;
struct driver_data *drv_data = spi_master_get_devdata(spi->master);
uint tx_thres, tx_hi_thres, rx_thres;
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
tx_thres = TX_THRESH_QUARK_X1000_DFLT;
tx_hi_thres = 0;
rx_thres = RX_THRESH_QUARK_X1000_DFLT;
break;
case LPSS_LPT_SSP:
case LPSS_BYT_SSP:
case LPSS_BSW_SSP:
case LPSS_SPT_SSP:
case LPSS_BXT_SSP:
config = lpss_get_config(drv_data);
tx_thres = config->tx_threshold_lo;
tx_hi_thres = config->tx_threshold_hi;
rx_thres = config->rx_threshold;
break;
default:
tx_thres = TX_THRESH_DFLT;
tx_hi_thres = 0;
rx_thres = RX_THRESH_DFLT;
break;
}
/* Only alloc on first setup */
chip = spi_get_ctldata(spi);
if (!chip) {
chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
if (!chip)
return -ENOMEM;
if (drv_data->ssp_type == CE4100_SSP) {
if (spi->chip_select > 4) {
dev_err(&spi->dev,
"failed setup: cs number must not be > 4.\n");
kfree(chip);
return -EINVAL;
}
chip->frm = spi->chip_select;
} else
chip->gpio_cs = -1;
chip->enable_dma = drv_data->master_info->enable_dma;
chip->timeout = TIMOUT_DFLT;
}
/* protocol drivers may change the chip settings, so...
* if chip_info exists, use it */
chip_info = spi->controller_data;
/* chip_info isn't always needed */
chip->cr1 = 0;
if (chip_info) {
if (chip_info->timeout)
chip->timeout = chip_info->timeout;
if (chip_info->tx_threshold)
tx_thres = chip_info->tx_threshold;
if (chip_info->tx_hi_threshold)
tx_hi_thres = chip_info->tx_hi_threshold;
if (chip_info->rx_threshold)
rx_thres = chip_info->rx_threshold;
chip->dma_threshold = 0;
if (chip_info->enable_loopback)
chip->cr1 = SSCR1_LBM;
}
chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres);
chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres)
| SSITF_TxHiThresh(tx_hi_thres);
/* set dma burst and threshold outside of chip_info path so that if
* chip_info goes away after setting chip->enable_dma, the
* burst and threshold can still respond to changes in bits_per_word */
if (chip->enable_dma) {
/* set up legal burst and threshold for dma */
if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
spi->bits_per_word,
&chip->dma_burst_size,
&chip->dma_threshold)) {
dev_warn(&spi->dev,
"in setup: DMA burst size reduced to match bits_per_word\n");
}
}
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
chip->threshold = (QUARK_X1000_SSCR1_RxTresh(rx_thres)
& QUARK_X1000_SSCR1_RFT)
| (QUARK_X1000_SSCR1_TxTresh(tx_thres)
& QUARK_X1000_SSCR1_TFT);
break;
default:
chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
(SSCR1_TxTresh(tx_thres) & SSCR1_TFT);
break;
}
chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH);
chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
| (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);
if (spi->mode & SPI_LOOP)
chip->cr1 |= SSCR1_LBM;
if (spi->bits_per_word <= 8) {
chip->n_bytes = 1;
chip->read = u8_reader;
chip->write = u8_writer;
} else if (spi->bits_per_word <= 16) {
chip->n_bytes = 2;
chip->read = u16_reader;
chip->write = u16_writer;
} else if (spi->bits_per_word <= 32) {
chip->n_bytes = 4;
chip->read = u32_reader;
chip->write = u32_writer;
}
spi_set_ctldata(spi, chip);
if (drv_data->ssp_type == CE4100_SSP)
return 0;
return setup_cs(spi, chip, chip_info);
}
static void cleanup(struct spi_device *spi)
{
struct chip_data *chip = spi_get_ctldata(spi);
struct driver_data *drv_data = spi_master_get_devdata(spi->master);
if (!chip)
return;
if (drv_data->ssp_type != CE4100_SSP && gpio_is_valid(chip->gpio_cs))
gpio_free(chip->gpio_cs);
kfree(chip);
}
#ifdef CONFIG_PCI
#ifdef CONFIG_ACPI
static const struct acpi_device_id pxa2xx_spi_acpi_match[] = {
{ "INT33C0", LPSS_LPT_SSP },
{ "INT33C1", LPSS_LPT_SSP },
{ "INT3430", LPSS_LPT_SSP },
{ "INT3431", LPSS_LPT_SSP },
{ "80860F0E", LPSS_BYT_SSP },
{ "8086228E", LPSS_BSW_SSP },
{ },
};
MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
{
unsigned int devid;
int port_id = -1;
if (adev && adev->pnp.unique_id &&
!kstrtouint(adev->pnp.unique_id, 0, &devid))
port_id = devid;
return port_id;
}
#else /* !CONFIG_ACPI */
static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
{
return -1;
}
#endif
/*
* PCI IDs of compound devices that integrate both host controller and private
* integrated DMA engine. Please note these are not used in module
* autoloading and probing in this module but matching the LPSS SSP type.
*/
static const struct pci_device_id pxa2xx_spi_pci_compound_match[] = {
/* SPT-LP */
{ PCI_VDEVICE(INTEL, 0x9d29), LPSS_SPT_SSP },
{ PCI_VDEVICE(INTEL, 0x9d2a), LPSS_SPT_SSP },
/* SPT-H */
{ PCI_VDEVICE(INTEL, 0xa129), LPSS_SPT_SSP },
{ PCI_VDEVICE(INTEL, 0xa12a), LPSS_SPT_SSP },
/* KBL-H */
{ PCI_VDEVICE(INTEL, 0xa2a9), LPSS_SPT_SSP },
{ PCI_VDEVICE(INTEL, 0xa2aa), LPSS_SPT_SSP },
/* BXT A-Step */
{ PCI_VDEVICE(INTEL, 0x0ac2), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x0ac4), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x0ac6), LPSS_BXT_SSP },
/* BXT B-Step */
{ PCI_VDEVICE(INTEL, 0x1ac2), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x1ac4), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x1ac6), LPSS_BXT_SSP },
/* APL */
{ PCI_VDEVICE(INTEL, 0x5ac2), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x5ac4), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x5ac6), LPSS_BXT_SSP },
{ },
};
static bool pxa2xx_spi_idma_filter(struct dma_chan *chan, void *param)
{
struct device *dev = param;
if (dev != chan->device->dev->parent)
return false;
return true;
}
static struct pxa2xx_spi_master *
pxa2xx_spi_init_pdata(struct platform_device *pdev)
{
struct pxa2xx_spi_master *pdata;
struct acpi_device *adev;
struct ssp_device *ssp;
struct resource *res;
const struct acpi_device_id *adev_id = NULL;
const struct pci_device_id *pcidev_id = NULL;
int type;
adev = ACPI_COMPANION(&pdev->dev);
if (dev_is_pci(pdev->dev.parent))
pcidev_id = pci_match_id(pxa2xx_spi_pci_compound_match,
to_pci_dev(pdev->dev.parent));
else if (adev)
adev_id = acpi_match_device(pdev->dev.driver->acpi_match_table,
&pdev->dev);
else
return NULL;
if (adev_id)
type = (int)adev_id->driver_data;
else if (pcidev_id)
type = (int)pcidev_id->driver_data;
else
return NULL;
spi/pxa2xx: fix memory corruption due to wrong size used in devm_kzalloc() ACPI part of the driver accidentally used sizeof(*ssp) instead of the correct sizeof(*pdata). This leads to nasty memory corruptions like the one below: BUG: unable to handle kernel paging request at 0000000749fd30b8 IP: [<ffffffff813fe8a1>] __list_del_entry+0x31/0xd0 PGD 0 Oops: 0000 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 30 Comm: kworker/0:1 Not tainted 3.10.0-rc6v3.10-rc6_sdhci_modprobe+ #443 task: ffff8801483a0940 ti: ffff88014839e000 task.ti: ffff88014839e000 RIP: 0010:[<ffffffff813fe8a1>] [<ffffffff813fe8a1>] __list_del_entry+0x31/0xd0 RSP: 0000:ffff88014839fde8 EFLAGS: 00010046 RAX: ffff880149fd30b0 RBX: ffff880149fd3040 RCX: dead000000200200 RDX: 0000000749fd30b0 RSI: ffff880149fd3058 RDI: ffff88014834d640 RBP: ffff88014839fde8 R08: ffff88014834d640 R09: 0000000000000001 R10: ffff8801483a0940 R11: 0000000000000001 R12: ffff880149fd3040 R13: ffffffff810e0b30 R14: ffff8801483a0940 R15: ffff88014834d640 FS: 0000000000000000(0000) GS:ffff880149e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000168 CR3: 0000000001e0b000 CR4: 00000000001407f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffff88014839fe48 ffffffff810e0baf ffffffff81120abd ffff88014839fe20 ffff8801483a0940 ffff8801483a0940 ffff8801483a0940 ffff8801486b1c90 ffff88014834d640 ffffffff810e0b30 0000000000000000 0000000000000000 Call Trace: [<ffffffff810e0baf>] worker_thread+0x7f/0x390 [<ffffffff81120abd>] ? trace_hardirqs_on+0xd/0x10 [<ffffffff810e0b30>] ? manage_workers.isra.22+0x2b0/0x2b0 [<ffffffff810e6c09>] kthread+0xd9/0xe0 [<ffffffff810f93df>] ? local_clock+0x3f/0x50 [<ffffffff810e6b30>] ? kthread_create_on_node+0x110/0x110 [<ffffffff818c5dec>] ret_from_fork+0x7c/0xb0 [<ffffffff810e6b30>] ? kthread_create_on_node+0x110/0x110 Fix this by using the right structure size in devm_kzalloc(). Reported-by: Jerome Blin <jerome.blin@intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Mark Brown <broonie@linaro.org> Cc: stable@vger.kernel.org # 3.9+
2013-06-20 14:44:22 +00:00
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return NULL;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return NULL;
ssp = &pdata->ssp;
ssp->phys_base = res->start;
ssp->mmio_base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(ssp->mmio_base))
return NULL;
if (pcidev_id) {
pdata->tx_param = pdev->dev.parent;
pdata->rx_param = pdev->dev.parent;
pdata->dma_filter = pxa2xx_spi_idma_filter;
}
ssp->clk = devm_clk_get(&pdev->dev, NULL);
ssp->irq = platform_get_irq(pdev, 0);
ssp->type = type;
ssp->pdev = pdev;
ssp->port_id = pxa2xx_spi_get_port_id(adev);
pdata->num_chipselect = 1;
pdata->enable_dma = true;
return pdata;
}
#else /* !CONFIG_PCI */
static inline struct pxa2xx_spi_master *
pxa2xx_spi_init_pdata(struct platform_device *pdev)
{
return NULL;
}
#endif
static int pxa2xx_spi_fw_translate_cs(struct spi_master *master, unsigned cs)
{
struct driver_data *drv_data = spi_master_get_devdata(master);
if (has_acpi_companion(&drv_data->pdev->dev)) {
switch (drv_data->ssp_type) {
/*
* For Atoms the ACPI DeviceSelection used by the Windows
* driver starts from 1 instead of 0 so translate it here
* to match what Linux expects.
*/
case LPSS_BYT_SSP:
case LPSS_BSW_SSP:
return cs - 1;
default:
break;
}
}
return cs;
}
static int pxa2xx_spi_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct pxa2xx_spi_master *platform_info;
struct spi_master *master;
struct driver_data *drv_data;
struct ssp_device *ssp;
const struct lpss_config *config;
int status;
u32 tmp;
platform_info = dev_get_platdata(dev);
if (!platform_info) {
platform_info = pxa2xx_spi_init_pdata(pdev);
if (!platform_info) {
dev_err(&pdev->dev, "missing platform data\n");
return -ENODEV;
}
}
ssp = pxa_ssp_request(pdev->id, pdev->name);
if (!ssp)
ssp = &platform_info->ssp;
if (!ssp->mmio_base) {
dev_err(&pdev->dev, "failed to get ssp\n");
return -ENODEV;
}
master = spi_alloc_master(dev, sizeof(struct driver_data));
if (!master) {
dev_err(&pdev->dev, "cannot alloc spi_master\n");
pxa_ssp_free(ssp);
return -ENOMEM;
}
drv_data = spi_master_get_devdata(master);
drv_data->master = master;
drv_data->master_info = platform_info;
drv_data->pdev = pdev;
drv_data->ssp = ssp;
master->dev.of_node = pdev->dev.of_node;
/* the spi->mode bits understood by this driver: */
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
master->bus_num = ssp->port_id;
master->dma_alignment = DMA_ALIGNMENT;
master->cleanup = cleanup;
master->setup = setup;
master->transfer_one_message = pxa2xx_spi_transfer_one_message;
master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;
master->fw_translate_cs = pxa2xx_spi_fw_translate_cs;
master->auto_runtime_pm = true;
master->flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX;
drv_data->ssp_type = ssp->type;
drv_data->ioaddr = ssp->mmio_base;
drv_data->ssdr_physical = ssp->phys_base + SSDR;
if (pxa25x_ssp_comp(drv_data)) {
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
break;
default:
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
break;
}
drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE;
drv_data->dma_cr1 = 0;
drv_data->clear_sr = SSSR_ROR;
drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR;
} else {
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE;
drv_data->dma_cr1 = DEFAULT_DMA_CR1;
drv_data->clear_sr = SSSR_ROR | SSSR_TINT;
drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR;
}
status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev),
drv_data);
if (status < 0) {
dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq);
goto out_error_master_alloc;
}
/* Setup DMA if requested */
if (platform_info->enable_dma) {
status = pxa2xx_spi_dma_setup(drv_data);
if (status) {
dev_dbg(dev, "no DMA channels available, using PIO\n");
platform_info->enable_dma = false;
} else {
master->can_dma = pxa2xx_spi_can_dma;
}
}
/* Enable SOC clock */
clk_prepare_enable(ssp->clk);
master->max_speed_hz = clk_get_rate(ssp->clk);
/* Load default SSP configuration */
pxa2xx_spi_write(drv_data, SSCR0, 0);
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
tmp = QUARK_X1000_SSCR1_RxTresh(RX_THRESH_QUARK_X1000_DFLT)
| QUARK_X1000_SSCR1_TxTresh(TX_THRESH_QUARK_X1000_DFLT);
pxa2xx_spi_write(drv_data, SSCR1, tmp);
/* using the Motorola SPI protocol and use 8 bit frame */
pxa2xx_spi_write(drv_data, SSCR0,
QUARK_X1000_SSCR0_Motorola
| QUARK_X1000_SSCR0_DataSize(8));
break;
default:
tmp = SSCR1_RxTresh(RX_THRESH_DFLT) |
SSCR1_TxTresh(TX_THRESH_DFLT);
pxa2xx_spi_write(drv_data, SSCR1, tmp);
tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8);
pxa2xx_spi_write(drv_data, SSCR0, tmp);
break;
}
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, 0);
if (!is_quark_x1000_ssp(drv_data))
pxa2xx_spi_write(drv_data, SSPSP, 0);
if (is_lpss_ssp(drv_data)) {
lpss_ssp_setup(drv_data);
config = lpss_get_config(drv_data);
if (config->reg_capabilities >= 0) {
tmp = __lpss_ssp_read_priv(drv_data,
config->reg_capabilities);
tmp &= LPSS_CAPS_CS_EN_MASK;
tmp >>= LPSS_CAPS_CS_EN_SHIFT;
platform_info->num_chipselect = ffz(tmp);
} else if (config->cs_num) {
platform_info->num_chipselect = config->cs_num;
}
}
master->num_chipselect = platform_info->num_chipselect;
tasklet_init(&drv_data->pump_transfers, pump_transfers,
(unsigned long)drv_data);
pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);
/* Register with the SPI framework */
platform_set_drvdata(pdev, drv_data);
status = devm_spi_register_master(&pdev->dev, master);
if (status != 0) {
dev_err(&pdev->dev, "problem registering spi master\n");
goto out_error_clock_enabled;
}
return status;
out_error_clock_enabled:
clk_disable_unprepare(ssp->clk);
pxa2xx_spi_dma_release(drv_data);
free_irq(ssp->irq, drv_data);
out_error_master_alloc:
spi_master_put(master);
pxa_ssp_free(ssp);
return status;
}
static int pxa2xx_spi_remove(struct platform_device *pdev)
{
struct driver_data *drv_data = platform_get_drvdata(pdev);
struct ssp_device *ssp;
if (!drv_data)
return 0;
ssp = drv_data->ssp;
pm_runtime_get_sync(&pdev->dev);
/* Disable the SSP at the peripheral and SOC level */
pxa2xx_spi_write(drv_data, SSCR0, 0);
clk_disable_unprepare(ssp->clk);
/* Release DMA */
if (drv_data->master_info->enable_dma)
pxa2xx_spi_dma_release(drv_data);
pm_runtime_put_noidle(&pdev->dev);
pm_runtime_disable(&pdev->dev);
/* Release IRQ */
free_irq(ssp->irq, drv_data);
/* Release SSP */
pxa_ssp_free(ssp);
return 0;
}
static void pxa2xx_spi_shutdown(struct platform_device *pdev)
{
int status = 0;
if ((status = pxa2xx_spi_remove(pdev)) != 0)
dev_err(&pdev->dev, "shutdown failed with %d\n", status);
}
#ifdef CONFIG_PM_SLEEP
static int pxa2xx_spi_suspend(struct device *dev)
{
struct driver_data *drv_data = dev_get_drvdata(dev);
struct ssp_device *ssp = drv_data->ssp;
int status = 0;
status = spi_master_suspend(drv_data->master);
if (status != 0)
return status;
pxa2xx_spi_write(drv_data, SSCR0, 0);
spi: pxa2xx: toggle clocks on suspend if not disabled by runtime PM If PM_RUNTIME is enabled, it is easy to trigger the following backtrace on pxa2xx hosts: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 1 at /home/lumag/linux/arch/arm/mach-pxa/clock.c:35 clk_disable+0xa0/0xa8() Modules linked in: CPU: 0 PID: 1 Comm: swapper Not tainted 3.17.0-00007-g1b3d2ee-dirty #104 [<c000de68>] (unwind_backtrace) from [<c000c078>] (show_stack+0x10/0x14) [<c000c078>] (show_stack) from [<c001d75c>] (warn_slowpath_common+0x6c/0x8c) [<c001d75c>] (warn_slowpath_common) from [<c001d818>] (warn_slowpath_null+0x1c/0x24) [<c001d818>] (warn_slowpath_null) from [<c0015e80>] (clk_disable+0xa0/0xa8) [<c0015e80>] (clk_disable) from [<c02507f8>] (pxa2xx_spi_suspend+0x2c/0x34) [<c02507f8>] (pxa2xx_spi_suspend) from [<c0200360>] (platform_pm_suspend+0x2c/0x54) [<c0200360>] (platform_pm_suspend) from [<c0207fec>] (dpm_run_callback.isra.14+0x2c/0x74) [<c0207fec>] (dpm_run_callback.isra.14) from [<c0209254>] (__device_suspend+0x120/0x2f8) [<c0209254>] (__device_suspend) from [<c0209a94>] (dpm_suspend+0x50/0x208) [<c0209a94>] (dpm_suspend) from [<c00455ac>] (suspend_devices_and_enter+0x8c/0x3a0) [<c00455ac>] (suspend_devices_and_enter) from [<c0045ad4>] (pm_suspend+0x214/0x2a8) [<c0045ad4>] (pm_suspend) from [<c04b5c34>] (test_suspend+0x14c/0x1dc) [<c04b5c34>] (test_suspend) from [<c000880c>] (do_one_initcall+0x8c/0x1fc) [<c000880c>] (do_one_initcall) from [<c04aecfc>] (kernel_init_freeable+0xf4/0x1b4) [<c04aecfc>] (kernel_init_freeable) from [<c0378078>] (kernel_init+0x8/0xec) [<c0378078>] (kernel_init) from [<c0009590>] (ret_from_fork+0x14/0x24) ---[ end trace 46524156d8faa4f6 ]--- This happens because suspend function tries to disable a clock that is already disabled by runtime_suspend callback. Add if (!pm_runtime_suspended()) checks to suspend/resume path. Fixes: 7d94a505858 (spi/pxa2xx: add support for runtime PM) Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> Reported-by: Andrea Adami <andrea.adami@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org
2014-11-06 11:08:29 +00:00
if (!pm_runtime_suspended(dev))
clk_disable_unprepare(ssp->clk);
return 0;
}
static int pxa2xx_spi_resume(struct device *dev)
{
struct driver_data *drv_data = dev_get_drvdata(dev);
struct ssp_device *ssp = drv_data->ssp;
int status = 0;
/* Enable the SSP clock */
spi: pxa2xx: toggle clocks on suspend if not disabled by runtime PM If PM_RUNTIME is enabled, it is easy to trigger the following backtrace on pxa2xx hosts: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 1 at /home/lumag/linux/arch/arm/mach-pxa/clock.c:35 clk_disable+0xa0/0xa8() Modules linked in: CPU: 0 PID: 1 Comm: swapper Not tainted 3.17.0-00007-g1b3d2ee-dirty #104 [<c000de68>] (unwind_backtrace) from [<c000c078>] (show_stack+0x10/0x14) [<c000c078>] (show_stack) from [<c001d75c>] (warn_slowpath_common+0x6c/0x8c) [<c001d75c>] (warn_slowpath_common) from [<c001d818>] (warn_slowpath_null+0x1c/0x24) [<c001d818>] (warn_slowpath_null) from [<c0015e80>] (clk_disable+0xa0/0xa8) [<c0015e80>] (clk_disable) from [<c02507f8>] (pxa2xx_spi_suspend+0x2c/0x34) [<c02507f8>] (pxa2xx_spi_suspend) from [<c0200360>] (platform_pm_suspend+0x2c/0x54) [<c0200360>] (platform_pm_suspend) from [<c0207fec>] (dpm_run_callback.isra.14+0x2c/0x74) [<c0207fec>] (dpm_run_callback.isra.14) from [<c0209254>] (__device_suspend+0x120/0x2f8) [<c0209254>] (__device_suspend) from [<c0209a94>] (dpm_suspend+0x50/0x208) [<c0209a94>] (dpm_suspend) from [<c00455ac>] (suspend_devices_and_enter+0x8c/0x3a0) [<c00455ac>] (suspend_devices_and_enter) from [<c0045ad4>] (pm_suspend+0x214/0x2a8) [<c0045ad4>] (pm_suspend) from [<c04b5c34>] (test_suspend+0x14c/0x1dc) [<c04b5c34>] (test_suspend) from [<c000880c>] (do_one_initcall+0x8c/0x1fc) [<c000880c>] (do_one_initcall) from [<c04aecfc>] (kernel_init_freeable+0xf4/0x1b4) [<c04aecfc>] (kernel_init_freeable) from [<c0378078>] (kernel_init+0x8/0xec) [<c0378078>] (kernel_init) from [<c0009590>] (ret_from_fork+0x14/0x24) ---[ end trace 46524156d8faa4f6 ]--- This happens because suspend function tries to disable a clock that is already disabled by runtime_suspend callback. Add if (!pm_runtime_suspended()) checks to suspend/resume path. Fixes: 7d94a505858 (spi/pxa2xx: add support for runtime PM) Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> Reported-by: Andrea Adami <andrea.adami@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org
2014-11-06 11:08:29 +00:00
if (!pm_runtime_suspended(dev))
clk_prepare_enable(ssp->clk);
/* Restore LPSS private register bits */
if (is_lpss_ssp(drv_data))
lpss_ssp_setup(drv_data);
/* Start the queue running */
status = spi_master_resume(drv_data->master);
if (status != 0) {
dev_err(dev, "problem starting queue (%d)\n", status);
return status;
}
return 0;
}
#endif
#ifdef CONFIG_PM
static int pxa2xx_spi_runtime_suspend(struct device *dev)
{
struct driver_data *drv_data = dev_get_drvdata(dev);
clk_disable_unprepare(drv_data->ssp->clk);
return 0;
}
static int pxa2xx_spi_runtime_resume(struct device *dev)
{
struct driver_data *drv_data = dev_get_drvdata(dev);
clk_prepare_enable(drv_data->ssp->clk);
return 0;
}
#endif
static const struct dev_pm_ops pxa2xx_spi_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume)
SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend,
pxa2xx_spi_runtime_resume, NULL)
};
static struct platform_driver driver = {
.driver = {
.name = "pxa2xx-spi",
.pm = &pxa2xx_spi_pm_ops,
.acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
},
.probe = pxa2xx_spi_probe,
.remove = pxa2xx_spi_remove,
.shutdown = pxa2xx_spi_shutdown,
};
static int __init pxa2xx_spi_init(void)
{
return platform_driver_register(&driver);
}
subsys_initcall(pxa2xx_spi_init);
static void __exit pxa2xx_spi_exit(void)
{
platform_driver_unregister(&driver);
}
module_exit(pxa2xx_spi_exit);