linux/drivers/spi/spi-imx.c

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// SPDX-License-Identifier: GPL-2.0+
// Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
// Copyright (C) 2008 Juergen Beisert
#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.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/spi/spi.h>
#include <linux/spi/spi_bitbang.h>
#include <linux/types.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/platform_data/dma-imx.h>
#include <linux/platform_data/spi-imx.h>
#define DRIVER_NAME "spi_imx"
static bool use_dma = true;
module_param(use_dma, bool, 0644);
MODULE_PARM_DESC(use_dma, "Enable usage of DMA when available (default)");
#define MXC_CSPIRXDATA 0x00
#define MXC_CSPITXDATA 0x04
#define MXC_CSPICTRL 0x08
#define MXC_CSPIINT 0x0c
#define MXC_RESET 0x1c
/* generic defines to abstract from the different register layouts */
#define MXC_INT_RR (1 << 0) /* Receive data ready interrupt */
#define MXC_INT_TE (1 << 1) /* Transmit FIFO empty interrupt */
#define MXC_INT_RDR BIT(4) /* Receive date threshold interrupt */
/* The maximum bytes that a sdma BD can transfer. */
#define MAX_SDMA_BD_BYTES (1 << 15)
#define MX51_ECSPI_CTRL_MAX_BURST 512
/* The maximum bytes that IMX53_ECSPI can transfer in slave mode.*/
#define MX53_MAX_TRANSFER_BYTES 512
enum spi_imx_devtype {
IMX1_CSPI,
IMX21_CSPI,
IMX27_CSPI,
IMX31_CSPI,
IMX35_CSPI, /* CSPI on all i.mx except above */
IMX51_ECSPI, /* ECSPI on i.mx51 */
IMX53_ECSPI, /* ECSPI on i.mx53 and later */
};
struct spi_imx_data;
struct spi_imx_devtype_data {
void (*intctrl)(struct spi_imx_data *, int);
int (*prepare_message)(struct spi_imx_data *, struct spi_message *);
int (*prepare_transfer)(struct spi_imx_data *, struct spi_device *,
struct spi_transfer *);
void (*trigger)(struct spi_imx_data *);
int (*rx_available)(struct spi_imx_data *);
void (*reset)(struct spi_imx_data *);
void (*setup_wml)(struct spi_imx_data *);
void (*disable)(struct spi_imx_data *);
bool has_dmamode;
bool has_slavemode;
unsigned int fifo_size;
bool dynamic_burst;
enum spi_imx_devtype devtype;
};
struct spi_imx_data {
struct spi_bitbang bitbang;
struct device *dev;
struct completion xfer_done;
void __iomem *base;
unsigned long base_phys;
struct clk *clk_per;
struct clk *clk_ipg;
unsigned long spi_clk;
unsigned int spi_bus_clk;
unsigned int bits_per_word;
unsigned int spi_drctl;
unsigned int count, remainder;
void (*tx)(struct spi_imx_data *);
void (*rx)(struct spi_imx_data *);
void *rx_buf;
const void *tx_buf;
unsigned int txfifo; /* number of words pushed in tx FIFO */
unsigned int dynamic_burst;
/* Slave mode */
bool slave_mode;
bool slave_aborted;
unsigned int slave_burst;
/* DMA */
bool usedma;
u32 wml;
struct completion dma_rx_completion;
struct completion dma_tx_completion;
const struct spi_imx_devtype_data *devtype_data;
};
static inline int is_imx27_cspi(struct spi_imx_data *d)
{
return d->devtype_data->devtype == IMX27_CSPI;
}
static inline int is_imx35_cspi(struct spi_imx_data *d)
{
return d->devtype_data->devtype == IMX35_CSPI;
}
static inline int is_imx51_ecspi(struct spi_imx_data *d)
{
return d->devtype_data->devtype == IMX51_ECSPI;
}
static inline int is_imx53_ecspi(struct spi_imx_data *d)
{
return d->devtype_data->devtype == IMX53_ECSPI;
}
#define MXC_SPI_BUF_RX(type) \
static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx) \
{ \
unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA); \
\
if (spi_imx->rx_buf) { \
*(type *)spi_imx->rx_buf = val; \
spi_imx->rx_buf += sizeof(type); \
} \
\
spi_imx->remainder -= sizeof(type); \
}
#define MXC_SPI_BUF_TX(type) \
static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx) \
{ \
type val = 0; \
\
if (spi_imx->tx_buf) { \
val = *(type *)spi_imx->tx_buf; \
spi_imx->tx_buf += sizeof(type); \
} \
\
spi_imx->count -= sizeof(type); \
\
writel(val, spi_imx->base + MXC_CSPITXDATA); \
}
MXC_SPI_BUF_RX(u8)
MXC_SPI_BUF_TX(u8)
MXC_SPI_BUF_RX(u16)
MXC_SPI_BUF_TX(u16)
MXC_SPI_BUF_RX(u32)
MXC_SPI_BUF_TX(u32)
/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
* (which is currently not the case in this driver)
*/
static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
256, 384, 512, 768, 1024};
/* MX21, MX27 */
static unsigned int spi_imx_clkdiv_1(unsigned int fin,
unsigned int fspi, unsigned int max, unsigned int *fres)
{
int i;
for (i = 2; i < max; i++)
if (fspi * mxc_clkdivs[i] >= fin)
break;
*fres = fin / mxc_clkdivs[i];
return i;
}
/* MX1, MX31, MX35, MX51 CSPI */
static unsigned int spi_imx_clkdiv_2(unsigned int fin,
unsigned int fspi, unsigned int *fres)
{
int i, div = 4;
for (i = 0; i < 7; i++) {
if (fspi * div >= fin)
goto out;
div <<= 1;
}
out:
*fres = fin / div;
return i;
}
static int spi_imx_bytes_per_word(const int bits_per_word)
{
if (bits_per_word <= 8)
return 1;
else if (bits_per_word <= 16)
return 2;
else
return 4;
}
static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
struct spi_transfer *transfer)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
if (!use_dma)
return false;
if (!master->dma_rx)
return false;
if (spi_imx->slave_mode)
return false;
if (transfer->len < spi_imx->devtype_data->fifo_size)
return false;
spi_imx->dynamic_burst = 0;
return true;
}
#define MX51_ECSPI_CTRL 0x08
#define MX51_ECSPI_CTRL_ENABLE (1 << 0)
#define MX51_ECSPI_CTRL_XCH (1 << 2)
#define MX51_ECSPI_CTRL_SMC (1 << 3)
#define MX51_ECSPI_CTRL_MODE_MASK (0xf << 4)
#define MX51_ECSPI_CTRL_DRCTL(drctl) ((drctl) << 16)
#define MX51_ECSPI_CTRL_POSTDIV_OFFSET 8
#define MX51_ECSPI_CTRL_PREDIV_OFFSET 12
#define MX51_ECSPI_CTRL_CS(cs) ((cs) << 18)
#define MX51_ECSPI_CTRL_BL_OFFSET 20
#define MX51_ECSPI_CTRL_BL_MASK (0xfff << 20)
#define MX51_ECSPI_CONFIG 0x0c
#define MX51_ECSPI_CONFIG_SCLKPHA(cs) (1 << ((cs) + 0))
#define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs) + 4))
#define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs) + 8))
#define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs) + 12))
#define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs) + 20))
#define MX51_ECSPI_INT 0x10
#define MX51_ECSPI_INT_TEEN (1 << 0)
#define MX51_ECSPI_INT_RREN (1 << 3)
#define MX51_ECSPI_INT_RDREN (1 << 4)
#define MX51_ECSPI_DMA 0x14
#define MX51_ECSPI_DMA_TX_WML(wml) ((wml) & 0x3f)
#define MX51_ECSPI_DMA_RX_WML(wml) (((wml) & 0x3f) << 16)
#define MX51_ECSPI_DMA_RXT_WML(wml) (((wml) & 0x3f) << 24)
#define MX51_ECSPI_DMA_TEDEN (1 << 7)
#define MX51_ECSPI_DMA_RXDEN (1 << 23)
#define MX51_ECSPI_DMA_RXTDEN (1 << 31)
#define MX51_ECSPI_STAT 0x18
#define MX51_ECSPI_STAT_RR (1 << 3)
#define MX51_ECSPI_TESTREG 0x20
#define MX51_ECSPI_TESTREG_LBC BIT(31)
static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
{
unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
#ifdef __LITTLE_ENDIAN
unsigned int bytes_per_word;
#endif
if (spi_imx->rx_buf) {
#ifdef __LITTLE_ENDIAN
bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
if (bytes_per_word == 1)
val = cpu_to_be32(val);
else if (bytes_per_word == 2)
val = (val << 16) | (val >> 16);
#endif
*(u32 *)spi_imx->rx_buf = val;
spi_imx->rx_buf += sizeof(u32);
}
spi_imx->remainder -= sizeof(u32);
}
static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
{
int unaligned;
u32 val;
unaligned = spi_imx->remainder % 4;
if (!unaligned) {
spi_imx_buf_rx_swap_u32(spi_imx);
return;
}
if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
spi_imx_buf_rx_u16(spi_imx);
return;
}
val = readl(spi_imx->base + MXC_CSPIRXDATA);
while (unaligned--) {
if (spi_imx->rx_buf) {
*(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
spi_imx->rx_buf++;
}
spi_imx->remainder--;
}
}
static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
{
u32 val = 0;
#ifdef __LITTLE_ENDIAN
unsigned int bytes_per_word;
#endif
if (spi_imx->tx_buf) {
val = *(u32 *)spi_imx->tx_buf;
spi_imx->tx_buf += sizeof(u32);
}
spi_imx->count -= sizeof(u32);
#ifdef __LITTLE_ENDIAN
bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
if (bytes_per_word == 1)
val = cpu_to_be32(val);
else if (bytes_per_word == 2)
val = (val << 16) | (val >> 16);
#endif
writel(val, spi_imx->base + MXC_CSPITXDATA);
}
static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
{
int unaligned;
u32 val = 0;
unaligned = spi_imx->count % 4;
if (!unaligned) {
spi_imx_buf_tx_swap_u32(spi_imx);
return;
}
if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
spi_imx_buf_tx_u16(spi_imx);
return;
}
while (unaligned--) {
if (spi_imx->tx_buf) {
val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
spi_imx->tx_buf++;
}
spi_imx->count--;
}
writel(val, spi_imx->base + MXC_CSPITXDATA);
}
static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
{
u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
if (spi_imx->rx_buf) {
int n_bytes = spi_imx->slave_burst % sizeof(val);
if (!n_bytes)
n_bytes = sizeof(val);
memcpy(spi_imx->rx_buf,
((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
spi_imx->rx_buf += n_bytes;
spi_imx->slave_burst -= n_bytes;
}
spi_imx->remainder -= sizeof(u32);
}
static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
{
u32 val = 0;
int n_bytes = spi_imx->count % sizeof(val);
if (!n_bytes)
n_bytes = sizeof(val);
if (spi_imx->tx_buf) {
memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
spi_imx->tx_buf, n_bytes);
val = cpu_to_be32(val);
spi_imx->tx_buf += n_bytes;
}
spi_imx->count -= n_bytes;
writel(val, spi_imx->base + MXC_CSPITXDATA);
}
/* MX51 eCSPI */
static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
unsigned int fspi, unsigned int *fres)
{
/*
* there are two 4-bit dividers, the pre-divider divides by
* $pre, the post-divider by 2^$post
*/
unsigned int pre, post;
unsigned int fin = spi_imx->spi_clk;
if (unlikely(fspi > fin))
return 0;
post = fls(fin) - fls(fspi);
if (fin > fspi << post)
post++;
/* now we have: (fin <= fspi << post) with post being minimal */
post = max(4U, post) - 4;
if (unlikely(post > 0xf)) {
dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
fspi, fin);
return 0xff;
}
pre = DIV_ROUND_UP(fin, fspi << post) - 1;
dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
__func__, fin, fspi, post, pre);
spi: spi-imx: Fix out-of-order CS/SCLK operation at low speeds Problem: -------- The problem this patch addresses has the following assumptions about the SPI bus setup: - The hardware used to find this is Freescale i.MX537 @ 1200MHz - The SPI SCLK operate at very low speed, less than 200 kHz - There are two SPI devices attached to the bus - Each device uses different GPIO for chipselect - Each device requires different SCLK signal polarity The observation of the SCLK and GPIO chipselect lines with a logic analyzer shows, that the SCLK polarity change does sometimes happen after the GPIO chipselect is asserted. The SPI slave device reacts on that by counting the SCLK polarity change as a clock pulse, which disrupts the communication with the SPI slave device. Explanation: ------------ We found an interesting correlation, that the maximum delay between the write into the ECSPIx_CONFIGREG register and the change of SCLK polarity at each SCLK frequency of 10 kHz, 20 kHz, 50 kHz and 100 kHz is 100 uS, 50 uS, 20 uS and 10 uS respectively. This lead us to a theory, that at SCLK frequency of 1 Hz, the delay would be 1 S. Therefore, the time it takes for the write to ECSPIx_CONFIGREG to take effect in the hardware is up to the duration of 1 tick of the SCLK clock. During this delay period, if the SCLK frequency is too low, the execution of the spi-imx.c driver can advance so much, that the GPIO chipselect will be asserted. The GPIO chipselect is asserted almost immediatelly. Solution: --------- The solution this patch presents is simple. We calculate the resulting SCLK clock first by dividing the ECSPI block clock by both dividers that are to be programmed into the configuration register. Based on the resulting SCLK clock, we derive the delay it will take for the changes to get really applied. We are extra careful here so we delay twice as long as we should. Note that the patch does not create additional overhead at high speeds as the delay will likely be close to zero there. Signed-off-by: Marek Vasut <marex@denx.de> To: linux-spi@vger.kernel.org Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Huang Shijie <b32955@freescale.com> Cc: Mark Brown <broonie@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-12-18 17:31:47 +00:00
/* Resulting frequency for the SCLK line. */
*fres = (fin / (pre + 1)) >> post;
return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
}
static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
{
unsigned val = 0;
if (enable & MXC_INT_TE)
val |= MX51_ECSPI_INT_TEEN;
if (enable & MXC_INT_RR)
val |= MX51_ECSPI_INT_RREN;
if (enable & MXC_INT_RDR)
val |= MX51_ECSPI_INT_RDREN;
writel(val, spi_imx->base + MX51_ECSPI_INT);
}
static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
{
u32 reg;
reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
reg |= MX51_ECSPI_CTRL_XCH;
writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
}
static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
{
u32 ctrl;
ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
}
static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
struct spi_message *msg)
{
struct spi_device *spi = msg->spi;
u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
u32 testreg;
u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
/* set Master or Slave mode */
if (spi_imx->slave_mode)
ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
else
ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
/*
* Enable SPI_RDY handling (falling edge/level triggered).
*/
if (spi->mode & SPI_READY)
ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
/* set chip select to use */
ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
/*
* The ctrl register must be written first, with the EN bit set other
* registers must not be written to.
*/
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
if (spi->mode & SPI_LOOP)
testreg |= MX51_ECSPI_TESTREG_LBC;
else
testreg &= ~MX51_ECSPI_TESTREG_LBC;
writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
/*
* eCSPI burst completion by Chip Select signal in Slave mode
* is not functional for imx53 Soc, config SPI burst completed when
* BURST_LENGTH + 1 bits are received
*/
if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
else
cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
if (spi->mode & SPI_CPHA)
cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
else
cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
if (spi->mode & SPI_CPOL) {
cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
} else {
cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
}
if (spi->mode & SPI_CS_HIGH)
cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
else
cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
return 0;
}
static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
struct spi_device *spi,
struct spi_transfer *t)
{
u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
u32 clk = t->speed_hz, delay;
/* Clear BL field and set the right value */
ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
ctrl |= (spi_imx->slave_burst * 8 - 1)
<< MX51_ECSPI_CTRL_BL_OFFSET;
else
ctrl |= (spi_imx->bits_per_word - 1)
<< MX51_ECSPI_CTRL_BL_OFFSET;
/* set clock speed */
ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
ctrl |= mx51_ecspi_clkdiv(spi_imx, t->speed_hz, &clk);
spi_imx->spi_bus_clk = clk;
if (spi_imx->usedma)
ctrl |= MX51_ECSPI_CTRL_SMC;
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
spi: spi-imx: Fix out-of-order CS/SCLK operation at low speeds Problem: -------- The problem this patch addresses has the following assumptions about the SPI bus setup: - The hardware used to find this is Freescale i.MX537 @ 1200MHz - The SPI SCLK operate at very low speed, less than 200 kHz - There are two SPI devices attached to the bus - Each device uses different GPIO for chipselect - Each device requires different SCLK signal polarity The observation of the SCLK and GPIO chipselect lines with a logic analyzer shows, that the SCLK polarity change does sometimes happen after the GPIO chipselect is asserted. The SPI slave device reacts on that by counting the SCLK polarity change as a clock pulse, which disrupts the communication with the SPI slave device. Explanation: ------------ We found an interesting correlation, that the maximum delay between the write into the ECSPIx_CONFIGREG register and the change of SCLK polarity at each SCLK frequency of 10 kHz, 20 kHz, 50 kHz and 100 kHz is 100 uS, 50 uS, 20 uS and 10 uS respectively. This lead us to a theory, that at SCLK frequency of 1 Hz, the delay would be 1 S. Therefore, the time it takes for the write to ECSPIx_CONFIGREG to take effect in the hardware is up to the duration of 1 tick of the SCLK clock. During this delay period, if the SCLK frequency is too low, the execution of the spi-imx.c driver can advance so much, that the GPIO chipselect will be asserted. The GPIO chipselect is asserted almost immediatelly. Solution: --------- The solution this patch presents is simple. We calculate the resulting SCLK clock first by dividing the ECSPI block clock by both dividers that are to be programmed into the configuration register. Based on the resulting SCLK clock, we derive the delay it will take for the changes to get really applied. We are extra careful here so we delay twice as long as we should. Note that the patch does not create additional overhead at high speeds as the delay will likely be close to zero there. Signed-off-by: Marek Vasut <marex@denx.de> To: linux-spi@vger.kernel.org Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Huang Shijie <b32955@freescale.com> Cc: Mark Brown <broonie@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-12-18 17:31:47 +00:00
/*
* Wait until the changes in the configuration register CONFIGREG
* propagate into the hardware. It takes exactly one tick of the
* SCLK clock, but we will wait two SCLK clock just to be sure. The
* effect of the delay it takes for the hardware to apply changes
* is noticable if the SCLK clock run very slow. In such a case, if
* the polarity of SCLK should be inverted, the GPIO ChipSelect might
* be asserted before the SCLK polarity changes, which would disrupt
* the SPI communication as the device on the other end would consider
* the change of SCLK polarity as a clock tick already.
*/
delay = (2 * 1000000) / clk;
if (likely(delay < 10)) /* SCLK is faster than 100 kHz */
udelay(delay);
else /* SCLK is _very_ slow */
usleep_range(delay, delay + 10);
return 0;
}
static void mx51_setup_wml(struct spi_imx_data *spi_imx)
{
/*
* Configure the DMA register: setup the watermark
* and enable DMA request.
*/
writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
}
static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
{
return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
}
static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
{
/* drain receive buffer */
while (mx51_ecspi_rx_available(spi_imx))
readl(spi_imx->base + MXC_CSPIRXDATA);
}
#define MX31_INTREG_TEEN (1 << 0)
#define MX31_INTREG_RREN (1 << 3)
#define MX31_CSPICTRL_ENABLE (1 << 0)
#define MX31_CSPICTRL_MASTER (1 << 1)
#define MX31_CSPICTRL_XCH (1 << 2)
#define MX31_CSPICTRL_SMC (1 << 3)
#define MX31_CSPICTRL_POL (1 << 4)
#define MX31_CSPICTRL_PHA (1 << 5)
#define MX31_CSPICTRL_SSCTL (1 << 6)
#define MX31_CSPICTRL_SSPOL (1 << 7)
#define MX31_CSPICTRL_BC_SHIFT 8
#define MX35_CSPICTRL_BL_SHIFT 20
#define MX31_CSPICTRL_CS_SHIFT 24
#define MX35_CSPICTRL_CS_SHIFT 12
#define MX31_CSPICTRL_DR_SHIFT 16
#define MX31_CSPI_DMAREG 0x10
#define MX31_DMAREG_RH_DEN (1<<4)
#define MX31_DMAREG_TH_DEN (1<<1)
#define MX31_CSPISTATUS 0x14
#define MX31_STATUS_RR (1 << 3)
#define MX31_CSPI_TESTREG 0x1C
#define MX31_TEST_LBC (1 << 14)
/* These functions also work for the i.MX35, but be aware that
* the i.MX35 has a slightly different register layout for bits
* we do not use here.
*/
static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
{
unsigned int val = 0;
if (enable & MXC_INT_TE)
val |= MX31_INTREG_TEEN;
if (enable & MXC_INT_RR)
val |= MX31_INTREG_RREN;
writel(val, spi_imx->base + MXC_CSPIINT);
}
static void mx31_trigger(struct spi_imx_data *spi_imx)
{
unsigned int reg;
reg = readl(spi_imx->base + MXC_CSPICTRL);
reg |= MX31_CSPICTRL_XCH;
writel(reg, spi_imx->base + MXC_CSPICTRL);
}
static int mx31_prepare_message(struct spi_imx_data *spi_imx,
struct spi_message *msg)
{
return 0;
}
static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
struct spi_device *spi,
struct spi_transfer *t)
{
unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
unsigned int clk;
reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &clk) <<
MX31_CSPICTRL_DR_SHIFT;
spi_imx->spi_bus_clk = clk;
if (is_imx35_cspi(spi_imx)) {
reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
reg |= MX31_CSPICTRL_SSCTL;
} else {
reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
}
if (spi->mode & SPI_CPHA)
reg |= MX31_CSPICTRL_PHA;
if (spi->mode & SPI_CPOL)
reg |= MX31_CSPICTRL_POL;
if (spi->mode & SPI_CS_HIGH)
reg |= MX31_CSPICTRL_SSPOL;
spi: imx: fix use of native chip-selects with devicetree The commonly used mechanism of specifying the hardware or native chip-select on an SPI device in devicetree (that is "cs-gpios = <0>") does not result in the native chip-select being configured for use. So external SPI devices that require use of the native chip-select will not work. You can successfully specify native chip-selects if using a platform setup by specifying the cs-gpio as negative offset by 32. And that works correctly. You cannot use the same method in devicetree. The logic in the spi-imx.c driver during probe uses core spi function of_spi_register_master() in spi.c to parse the "cs-gpios" devicetree tag. For valid GPIO values that will be recorded for use, all other entries in the cs_gpios list will be set to -ENOENT. So entries like "<0>" will be set to -ENOENT in the cs_gpios list. When the SPI device registers are setup the code will use the GPIO listed in the cs_gpios list for the desired chip-select. If the cs_gpio is less then 0 then it is intended to be for a native chip-select, and its cs_gpio value is added to 32 to get the chipselect number to use. Problem is that with devicetree this can only ever be -ENOENT (which is -2), and that alone results in an invalid chip-select number. But also doesn't allow selection of the native chip-select at all. To fix, if the cs_gpio specified for this spi device is not a valid GPIO then use the "chip_select" (that is the native chip-select number) for hardware setup. Signed-off-by: Greg Ungerer <gerg@linux-m68k.org> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Tested-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-07-11 04:22:11 +00:00
if (!gpio_is_valid(spi->cs_gpio))
reg |= (spi->chip_select) <<
(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
MX31_CSPICTRL_CS_SHIFT);
if (spi_imx->usedma)
reg |= MX31_CSPICTRL_SMC;
writel(reg, spi_imx->base + MXC_CSPICTRL);
reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
if (spi->mode & SPI_LOOP)
reg |= MX31_TEST_LBC;
else
reg &= ~MX31_TEST_LBC;
writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
if (spi_imx->usedma) {
/*
* configure DMA requests when RXFIFO is half full and
* when TXFIFO is half empty
*/
writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
spi_imx->base + MX31_CSPI_DMAREG);
}
return 0;
}
static int mx31_rx_available(struct spi_imx_data *spi_imx)
{
return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
}
static void mx31_reset(struct spi_imx_data *spi_imx)
{
/* drain receive buffer */
while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
readl(spi_imx->base + MXC_CSPIRXDATA);
}
#define MX21_INTREG_RR (1 << 4)
#define MX21_INTREG_TEEN (1 << 9)
#define MX21_INTREG_RREN (1 << 13)
#define MX21_CSPICTRL_POL (1 << 5)
#define MX21_CSPICTRL_PHA (1 << 6)
#define MX21_CSPICTRL_SSPOL (1 << 8)
#define MX21_CSPICTRL_XCH (1 << 9)
#define MX21_CSPICTRL_ENABLE (1 << 10)
#define MX21_CSPICTRL_MASTER (1 << 11)
#define MX21_CSPICTRL_DR_SHIFT 14
#define MX21_CSPICTRL_CS_SHIFT 19
static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
{
unsigned int val = 0;
if (enable & MXC_INT_TE)
val |= MX21_INTREG_TEEN;
if (enable & MXC_INT_RR)
val |= MX21_INTREG_RREN;
writel(val, spi_imx->base + MXC_CSPIINT);
}
static void mx21_trigger(struct spi_imx_data *spi_imx)
{
unsigned int reg;
reg = readl(spi_imx->base + MXC_CSPICTRL);
reg |= MX21_CSPICTRL_XCH;
writel(reg, spi_imx->base + MXC_CSPICTRL);
}
static int mx21_prepare_message(struct spi_imx_data *spi_imx,
struct spi_message *msg)
{
return 0;
}
static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
struct spi_device *spi,
struct spi_transfer *t)
{
unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
unsigned int clk;
reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, t->speed_hz, max, &clk)
<< MX21_CSPICTRL_DR_SHIFT;
spi_imx->spi_bus_clk = clk;
reg |= spi_imx->bits_per_word - 1;
if (spi->mode & SPI_CPHA)
reg |= MX21_CSPICTRL_PHA;
if (spi->mode & SPI_CPOL)
reg |= MX21_CSPICTRL_POL;
if (spi->mode & SPI_CS_HIGH)
reg |= MX21_CSPICTRL_SSPOL;
spi: imx: fix use of native chip-selects with devicetree The commonly used mechanism of specifying the hardware or native chip-select on an SPI device in devicetree (that is "cs-gpios = <0>") does not result in the native chip-select being configured for use. So external SPI devices that require use of the native chip-select will not work. You can successfully specify native chip-selects if using a platform setup by specifying the cs-gpio as negative offset by 32. And that works correctly. You cannot use the same method in devicetree. The logic in the spi-imx.c driver during probe uses core spi function of_spi_register_master() in spi.c to parse the "cs-gpios" devicetree tag. For valid GPIO values that will be recorded for use, all other entries in the cs_gpios list will be set to -ENOENT. So entries like "<0>" will be set to -ENOENT in the cs_gpios list. When the SPI device registers are setup the code will use the GPIO listed in the cs_gpios list for the desired chip-select. If the cs_gpio is less then 0 then it is intended to be for a native chip-select, and its cs_gpio value is added to 32 to get the chipselect number to use. Problem is that with devicetree this can only ever be -ENOENT (which is -2), and that alone results in an invalid chip-select number. But also doesn't allow selection of the native chip-select at all. To fix, if the cs_gpio specified for this spi device is not a valid GPIO then use the "chip_select" (that is the native chip-select number) for hardware setup. Signed-off-by: Greg Ungerer <gerg@linux-m68k.org> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Tested-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-07-11 04:22:11 +00:00
if (!gpio_is_valid(spi->cs_gpio))
reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
writel(reg, spi_imx->base + MXC_CSPICTRL);
return 0;
}
static int mx21_rx_available(struct spi_imx_data *spi_imx)
{
return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
}
static void mx21_reset(struct spi_imx_data *spi_imx)
{
writel(1, spi_imx->base + MXC_RESET);
}
#define MX1_INTREG_RR (1 << 3)
#define MX1_INTREG_TEEN (1 << 8)
#define MX1_INTREG_RREN (1 << 11)
#define MX1_CSPICTRL_POL (1 << 4)
#define MX1_CSPICTRL_PHA (1 << 5)
#define MX1_CSPICTRL_XCH (1 << 8)
#define MX1_CSPICTRL_ENABLE (1 << 9)
#define MX1_CSPICTRL_MASTER (1 << 10)
#define MX1_CSPICTRL_DR_SHIFT 13
static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
{
unsigned int val = 0;
if (enable & MXC_INT_TE)
val |= MX1_INTREG_TEEN;
if (enable & MXC_INT_RR)
val |= MX1_INTREG_RREN;
writel(val, spi_imx->base + MXC_CSPIINT);
}
static void mx1_trigger(struct spi_imx_data *spi_imx)
{
unsigned int reg;
reg = readl(spi_imx->base + MXC_CSPICTRL);
reg |= MX1_CSPICTRL_XCH;
writel(reg, spi_imx->base + MXC_CSPICTRL);
}
static int mx1_prepare_message(struct spi_imx_data *spi_imx,
struct spi_message *msg)
{
return 0;
}
static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
struct spi_device *spi,
struct spi_transfer *t)
{
unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
unsigned int clk;
reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &clk) <<
MX1_CSPICTRL_DR_SHIFT;
spi_imx->spi_bus_clk = clk;
reg |= spi_imx->bits_per_word - 1;
if (spi->mode & SPI_CPHA)
reg |= MX1_CSPICTRL_PHA;
if (spi->mode & SPI_CPOL)
reg |= MX1_CSPICTRL_POL;
writel(reg, spi_imx->base + MXC_CSPICTRL);
return 0;
}
static int mx1_rx_available(struct spi_imx_data *spi_imx)
{
return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
}
static void mx1_reset(struct spi_imx_data *spi_imx)
{
writel(1, spi_imx->base + MXC_RESET);
}
static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
.intctrl = mx1_intctrl,
.prepare_message = mx1_prepare_message,
.prepare_transfer = mx1_prepare_transfer,
.trigger = mx1_trigger,
.rx_available = mx1_rx_available,
.reset = mx1_reset,
.fifo_size = 8,
.has_dmamode = false,
.dynamic_burst = false,
.has_slavemode = false,
.devtype = IMX1_CSPI,
};
static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
.intctrl = mx21_intctrl,
.prepare_message = mx21_prepare_message,
.prepare_transfer = mx21_prepare_transfer,
.trigger = mx21_trigger,
.rx_available = mx21_rx_available,
.reset = mx21_reset,
.fifo_size = 8,
.has_dmamode = false,
.dynamic_burst = false,
.has_slavemode = false,
.devtype = IMX21_CSPI,
};
static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
/* i.mx27 cspi shares the functions with i.mx21 one */
.intctrl = mx21_intctrl,
.prepare_message = mx21_prepare_message,
.prepare_transfer = mx21_prepare_transfer,
.trigger = mx21_trigger,
.rx_available = mx21_rx_available,
.reset = mx21_reset,
.fifo_size = 8,
.has_dmamode = false,
.dynamic_burst = false,
.has_slavemode = false,
.devtype = IMX27_CSPI,
};
static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
.intctrl = mx31_intctrl,
.prepare_message = mx31_prepare_message,
.prepare_transfer = mx31_prepare_transfer,
.trigger = mx31_trigger,
.rx_available = mx31_rx_available,
.reset = mx31_reset,
.fifo_size = 8,
.has_dmamode = false,
.dynamic_burst = false,
.has_slavemode = false,
.devtype = IMX31_CSPI,
};
static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
/* i.mx35 and later cspi shares the functions with i.mx31 one */
.intctrl = mx31_intctrl,
.prepare_message = mx31_prepare_message,
.prepare_transfer = mx31_prepare_transfer,
.trigger = mx31_trigger,
.rx_available = mx31_rx_available,
.reset = mx31_reset,
.fifo_size = 8,
.has_dmamode = true,
.dynamic_burst = false,
.has_slavemode = false,
.devtype = IMX35_CSPI,
};
static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
.intctrl = mx51_ecspi_intctrl,
.prepare_message = mx51_ecspi_prepare_message,
.prepare_transfer = mx51_ecspi_prepare_transfer,
.trigger = mx51_ecspi_trigger,
.rx_available = mx51_ecspi_rx_available,
.reset = mx51_ecspi_reset,
.setup_wml = mx51_setup_wml,
.fifo_size = 64,
.has_dmamode = true,
.dynamic_burst = true,
.has_slavemode = true,
.disable = mx51_ecspi_disable,
.devtype = IMX51_ECSPI,
};
static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
.intctrl = mx51_ecspi_intctrl,
.prepare_message = mx51_ecspi_prepare_message,
.prepare_transfer = mx51_ecspi_prepare_transfer,
.trigger = mx51_ecspi_trigger,
.rx_available = mx51_ecspi_rx_available,
.reset = mx51_ecspi_reset,
.fifo_size = 64,
.has_dmamode = true,
.has_slavemode = true,
.disable = mx51_ecspi_disable,
.devtype = IMX53_ECSPI,
};
static const struct platform_device_id spi_imx_devtype[] = {
{
.name = "imx1-cspi",
.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
}, {
.name = "imx21-cspi",
.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
}, {
.name = "imx27-cspi",
.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
}, {
.name = "imx31-cspi",
.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
}, {
.name = "imx35-cspi",
.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
}, {
.name = "imx51-ecspi",
.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
}, {
.name = "imx53-ecspi",
.driver_data = (kernel_ulong_t) &imx53_ecspi_devtype_data,
}, {
/* sentinel */
}
};
static const struct of_device_id spi_imx_dt_ids[] = {
{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
static void spi_imx_chipselect(struct spi_device *spi, int is_active)
{
int active = is_active != BITBANG_CS_INACTIVE;
int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
if (spi->mode & SPI_NO_CS)
return;
if (!gpio_is_valid(spi->cs_gpio))
return;
gpio_set_value(spi->cs_gpio, dev_is_lowactive ^ active);
}
static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
{
u32 ctrl;
ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
}
static void spi_imx_push(struct spi_imx_data *spi_imx)
{
unsigned int burst_len, fifo_words;
if (spi_imx->dynamic_burst)
fifo_words = 4;
else
fifo_words = spi_imx_bytes_per_word(spi_imx->bits_per_word);
/*
* Reload the FIFO when the remaining bytes to be transferred in the
* current burst is 0. This only applies when bits_per_word is a
* multiple of 8.
*/
if (!spi_imx->remainder) {
if (spi_imx->dynamic_burst) {
/* We need to deal unaligned data first */
burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
if (!burst_len)
burst_len = MX51_ECSPI_CTRL_MAX_BURST;
spi_imx_set_burst_len(spi_imx, burst_len * 8);
spi_imx->remainder = burst_len;
} else {
spi_imx->remainder = fifo_words;
}
}
while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
if (!spi_imx->count)
break;
if (spi_imx->dynamic_burst &&
spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder,
fifo_words))
break;
spi_imx->tx(spi_imx);
spi_imx->txfifo++;
}
if (!spi_imx->slave_mode)
spi_imx->devtype_data->trigger(spi_imx);
}
static irqreturn_t spi_imx_isr(int irq, void *dev_id)
{
struct spi_imx_data *spi_imx = dev_id;
while (spi_imx->txfifo &&
spi_imx->devtype_data->rx_available(spi_imx)) {
spi_imx->rx(spi_imx);
spi_imx->txfifo--;
}
if (spi_imx->count) {
spi_imx_push(spi_imx);
return IRQ_HANDLED;
}
if (spi_imx->txfifo) {
/* No data left to push, but still waiting for rx data,
* enable receive data available interrupt.
*/
spi_imx->devtype_data->intctrl(
spi_imx, MXC_INT_RR);
return IRQ_HANDLED;
}
spi_imx->devtype_data->intctrl(spi_imx, 0);
complete(&spi_imx->xfer_done);
return IRQ_HANDLED;
}
static int spi_imx_dma_configure(struct spi_master *master)
{
int ret;
enum dma_slave_buswidth buswidth;
struct dma_slave_config rx = {}, tx = {};
struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
case 4:
buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
break;
case 2:
buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
break;
case 1:
buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
break;
default:
return -EINVAL;
}
tx.direction = DMA_MEM_TO_DEV;
tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
tx.dst_addr_width = buswidth;
tx.dst_maxburst = spi_imx->wml;
ret = dmaengine_slave_config(master->dma_tx, &tx);
if (ret) {
dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
return ret;
}
rx.direction = DMA_DEV_TO_MEM;
rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
rx.src_addr_width = buswidth;
rx.src_maxburst = spi_imx->wml;
ret = dmaengine_slave_config(master->dma_rx, &rx);
if (ret) {
dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
return ret;
}
return 0;
}
static int spi_imx_setupxfer(struct spi_device *spi,
struct spi_transfer *t)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
if (!t)
return 0;
spi_imx->bits_per_word = t->bits_per_word;
/*
* Initialize the functions for transfer. To transfer non byte-aligned
* words, we have to use multiple word-size bursts, we can't use
* dynamic_burst in that case.
*/
if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
(spi_imx->bits_per_word == 8 ||
spi_imx->bits_per_word == 16 ||
spi_imx->bits_per_word == 32)) {
spi_imx->rx = spi_imx_buf_rx_swap;
spi_imx->tx = spi_imx_buf_tx_swap;
spi_imx->dynamic_burst = 1;
} else {
if (spi_imx->bits_per_word <= 8) {
spi_imx->rx = spi_imx_buf_rx_u8;
spi_imx->tx = spi_imx_buf_tx_u8;
} else if (spi_imx->bits_per_word <= 16) {
spi_imx->rx = spi_imx_buf_rx_u16;
spi_imx->tx = spi_imx_buf_tx_u16;
} else {
spi_imx->rx = spi_imx_buf_rx_u32;
spi_imx->tx = spi_imx_buf_tx_u32;
}
spi_imx->dynamic_burst = 0;
}
if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
spi_imx->usedma = true;
else
spi_imx->usedma = false;
if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
spi_imx->rx = mx53_ecspi_rx_slave;
spi_imx->tx = mx53_ecspi_tx_slave;
spi_imx->slave_burst = t->len;
}
spi_imx->devtype_data->prepare_transfer(spi_imx, spi, t);
return 0;
}
static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
{
struct spi_master *master = spi_imx->bitbang.master;
if (master->dma_rx) {
dma_release_channel(master->dma_rx);
master->dma_rx = NULL;
}
if (master->dma_tx) {
dma_release_channel(master->dma_tx);
master->dma_tx = NULL;
}
}
static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
struct spi_master *master)
{
int ret;
/* use pio mode for i.mx6dl chip TKT238285 */
if (of_machine_is_compatible("fsl,imx6dl"))
return 0;
spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
/* Prepare for TX DMA: */
master->dma_tx = dma_request_chan(dev, "tx");
if (IS_ERR(master->dma_tx)) {
ret = PTR_ERR(master->dma_tx);
dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
master->dma_tx = NULL;
goto err;
}
/* Prepare for RX : */
master->dma_rx = dma_request_chan(dev, "rx");
if (IS_ERR(master->dma_rx)) {
ret = PTR_ERR(master->dma_rx);
dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
master->dma_rx = NULL;
goto err;
}
init_completion(&spi_imx->dma_rx_completion);
init_completion(&spi_imx->dma_tx_completion);
master->can_dma = spi_imx_can_dma;
master->max_dma_len = MAX_SDMA_BD_BYTES;
spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
SPI_MASTER_MUST_TX;
return 0;
err:
spi_imx_sdma_exit(spi_imx);
return ret;
}
static void spi_imx_dma_rx_callback(void *cookie)
{
struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
complete(&spi_imx->dma_rx_completion);
}
static void spi_imx_dma_tx_callback(void *cookie)
{
struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
complete(&spi_imx->dma_tx_completion);
}
static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
{
unsigned long timeout = 0;
/* Time with actual data transfer and CS change delay related to HW */
timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
/* Add extra second for scheduler related activities */
timeout += 1;
/* Double calculated timeout */
return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
}
static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
struct spi_transfer *transfer)
{
struct dma_async_tx_descriptor *desc_tx, *desc_rx;
unsigned long transfer_timeout;
unsigned long timeout;
struct spi_master *master = spi_imx->bitbang.master;
struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
unsigned int bytes_per_word, i;
int ret;
/* Get the right burst length from the last sg to ensure no tail data */
bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
break;
}
/* Use 1 as wml in case no available burst length got */
if (i == 0)
i = 1;
spi_imx->wml = i;
ret = spi_imx_dma_configure(master);
if (ret)
return ret;
if (!spi_imx->devtype_data->setup_wml) {
dev_err(spi_imx->dev, "No setup_wml()?\n");
return -EINVAL;
}
spi_imx->devtype_data->setup_wml(spi_imx);
/*
* The TX DMA setup starts the transfer, so make sure RX is configured
* before TX.
*/
desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
rx->sgl, rx->nents, DMA_DEV_TO_MEM,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_rx)
return -EINVAL;
desc_rx->callback = spi_imx_dma_rx_callback;
desc_rx->callback_param = (void *)spi_imx;
dmaengine_submit(desc_rx);
reinit_completion(&spi_imx->dma_rx_completion);
dma_async_issue_pending(master->dma_rx);
desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
tx->sgl, tx->nents, DMA_MEM_TO_DEV,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_tx) {
dmaengine_terminate_all(master->dma_tx);
return -EINVAL;
}
desc_tx->callback = spi_imx_dma_tx_callback;
desc_tx->callback_param = (void *)spi_imx;
dmaengine_submit(desc_tx);
reinit_completion(&spi_imx->dma_tx_completion);
dma_async_issue_pending(master->dma_tx);
transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
/* Wait SDMA to finish the data transfer.*/
timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
transfer_timeout);
if (!timeout) {
dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
dmaengine_terminate_all(master->dma_tx);
dmaengine_terminate_all(master->dma_rx);
return -ETIMEDOUT;
}
timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
transfer_timeout);
if (!timeout) {
dev_err(&master->dev, "I/O Error in DMA RX\n");
spi_imx->devtype_data->reset(spi_imx);
dmaengine_terminate_all(master->dma_rx);
return -ETIMEDOUT;
}
return transfer->len;
}
static int spi_imx_pio_transfer(struct spi_device *spi,
struct spi_transfer *transfer)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
spi: imx: wait_for_completion_timeout(..) for PIO transfers In some rare cases I see the following 'task blocked' information. It looks like the PIO transfer has some problems and never succeeds. Make use of wait_for_completion_timeout(..) to detect this case and return -ETIMEDOUT. [ 240.246067] INFO: task hexdump:1660 blocked for more than 120 seconds. [ 240.246089] Not tainted 4.1.17 0000001 [ 240.246099] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 240.246109] hexdump D c0575548 0 1660 1 0x00000000 [ 240.246132] Backtrace: [ 240.246166] [<c057524c>] (__schedule) from [<c0575a84>] (schedule+0x40/0xa4) [ 240.246176] r10:00000000 r9:c07f1300 r8:c07b8408 r7:c0576518 r6:7fffffff r5:7fffffff [ 240.246210] r4:ee972e7c [ 240.246233] [<c0575a44>] (schedule) from [<c0578544>] (schedule_timeout+0x174/0x274) [ 240.246254] [<c05783d0>] (schedule_timeout) from [<c0576518>] (wait_for_common+0xc0/0x164) [ 240.246263] r10:00000000 r9:c07f1300 r8:00000002 r7:00000000 r6:7fffffff r5:ee972e78 [ 240.246294] r4:ee972e7c [ 240.246314] [<c0576458>] (wait_for_common) from [<c05765dc>] (wait_for_completion+0x20/0x24) [ 240.246324] r10:ee972e50 r8:00000001 r7:c3976200 r6:ee972c00 r5:ee972e50 r4:c2c87d28 [ 240.246367] [<c05765bc>] (wait_for_completion) from [<c03f6b04>] (spi_imx_transfer+0xe8/0x3cc) [ 240.246393] [<c03f6a1c>] (spi_imx_transfer) from [<c03f50e4>] (spi_bitbang_transfer_one+0xb4/0x250) [ 240.246403] r10:ee972e50 r8:00000001 r7:00000000 r6:c2c87da0 r5:00000000 r4:c2c87d28 [ 240.246443] [<c03f5030>] (spi_bitbang_transfer_one) from [<c03f36e8>] (__spi_pump_messages+0x36c/0x6b4) [ 240.246452] r10:ee9e5010 r9:00000001 r8:ee9e5010 r7:00000000 r6:c2c87da0 r5:c2c87d6c [ 240.246483] r4:ee972c00 [ 240.246503] [<c03f337c>] (__spi_pump_messages) from [<c03f3b68>] (__spi_sync+0x138/0x1e4) [ 240.246512] r10:00000000 r9:00000000 r8:c03f25a8 r7:00000000 r6:ee972c00 r5:c3976200 [ 240.246542] r4:c2c87da0 [ 240.246562] [<c03f3a30>] (__spi_sync) from [<c03f3c50>] (spi_sync+0x1c/0x20) [ 240.246571] r10:00040000 r9:00000000 r8:c3976200 r7:00000000 r6:ee973300 r5:c2c87da0 [ 240.246602] r4:ee973014 [ 240.246623] [<c03f3c34>] (spi_sync) from [<c03f0210>] (m25p80_read+0xf8/0x124) [ 240.246641] [<c03f0118>] (m25p80_read) from [<c03f1528>] (spi_nor_read+0x64/0x80) [ 240.246651] r10:00004000 r8:00004000 r7:00000000 r6:00040000 r5:00000000 r4:ee973014 [ 240.246698] [<c03f14c4>] (spi_nor_read) from [<c03cdcb4>] (mtd_read+0x98/0xcc) [ 240.246708] r7:c2c87ea0 r6:ee973098 r5:00000000 r4:001c0000 [ 240.246740] [<c03cdc1c>] (mtd_read) from [<c03d300c>] (mtdchar_read+0xcc/0x204) [ 240.246750] r9:ed424000 r8:00000000 r7:b495d018 r6:c2c87f78 r5:00000000 r4:00040000 [ 240.246793] [<c03d2f40>] (mtdchar_read) from [<c013b1c4>] (__vfs_read+0x3c/0xe0) [ 240.246803] r10:00004000 r9:00000000 r8:c2c87f78 r7:b495d018 r6:c2c87f78 r5:c05c8104 [ 240.246833] r4:c32fe600 [ 240.246852] [<c013b188>] (__vfs_read) from [<c013befc>] (vfs_read+0x98/0x154) [ 240.246861] r10:00000000 r8:00040000 r7:00004000 r6:c2c87f78 r5:b495d018 r4:c32fe600 [ 240.246899] [<c013be64>] (vfs_read) from [<c013c008>] (SyS_read+0x50/0x90) [ 240.246908] r10:00000000 r8:00040000 r7:b495d018 r6:00004000 r5:c32fe601 r4:c32fe600 [ 240.246953] [<c013bfb8>] (SyS_read) from [<c000fa60>] (ret_fast_syscall+0x0/0x3c) [ 240.246962] r9:c2c86000 r8:c000fc04 r7:00000003 r6:00004000 r5:00000000 r4:b495d018 Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-06-21 12:12:54 +00:00
unsigned long transfer_timeout;
unsigned long timeout;
spi_imx->tx_buf = transfer->tx_buf;
spi_imx->rx_buf = transfer->rx_buf;
spi_imx->count = transfer->len;
spi_imx->txfifo = 0;
spi_imx->remainder = 0;
reinit_completion(&spi_imx->xfer_done);
spi_imx_push(spi_imx);
spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
spi: imx: wait_for_completion_timeout(..) for PIO transfers In some rare cases I see the following 'task blocked' information. It looks like the PIO transfer has some problems and never succeeds. Make use of wait_for_completion_timeout(..) to detect this case and return -ETIMEDOUT. [ 240.246067] INFO: task hexdump:1660 blocked for more than 120 seconds. [ 240.246089] Not tainted 4.1.17 0000001 [ 240.246099] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 240.246109] hexdump D c0575548 0 1660 1 0x00000000 [ 240.246132] Backtrace: [ 240.246166] [<c057524c>] (__schedule) from [<c0575a84>] (schedule+0x40/0xa4) [ 240.246176] r10:00000000 r9:c07f1300 r8:c07b8408 r7:c0576518 r6:7fffffff r5:7fffffff [ 240.246210] r4:ee972e7c [ 240.246233] [<c0575a44>] (schedule) from [<c0578544>] (schedule_timeout+0x174/0x274) [ 240.246254] [<c05783d0>] (schedule_timeout) from [<c0576518>] (wait_for_common+0xc0/0x164) [ 240.246263] r10:00000000 r9:c07f1300 r8:00000002 r7:00000000 r6:7fffffff r5:ee972e78 [ 240.246294] r4:ee972e7c [ 240.246314] [<c0576458>] (wait_for_common) from [<c05765dc>] (wait_for_completion+0x20/0x24) [ 240.246324] r10:ee972e50 r8:00000001 r7:c3976200 r6:ee972c00 r5:ee972e50 r4:c2c87d28 [ 240.246367] [<c05765bc>] (wait_for_completion) from [<c03f6b04>] (spi_imx_transfer+0xe8/0x3cc) [ 240.246393] [<c03f6a1c>] (spi_imx_transfer) from [<c03f50e4>] (spi_bitbang_transfer_one+0xb4/0x250) [ 240.246403] r10:ee972e50 r8:00000001 r7:00000000 r6:c2c87da0 r5:00000000 r4:c2c87d28 [ 240.246443] [<c03f5030>] (spi_bitbang_transfer_one) from [<c03f36e8>] (__spi_pump_messages+0x36c/0x6b4) [ 240.246452] r10:ee9e5010 r9:00000001 r8:ee9e5010 r7:00000000 r6:c2c87da0 r5:c2c87d6c [ 240.246483] r4:ee972c00 [ 240.246503] [<c03f337c>] (__spi_pump_messages) from [<c03f3b68>] (__spi_sync+0x138/0x1e4) [ 240.246512] r10:00000000 r9:00000000 r8:c03f25a8 r7:00000000 r6:ee972c00 r5:c3976200 [ 240.246542] r4:c2c87da0 [ 240.246562] [<c03f3a30>] (__spi_sync) from [<c03f3c50>] (spi_sync+0x1c/0x20) [ 240.246571] r10:00040000 r9:00000000 r8:c3976200 r7:00000000 r6:ee973300 r5:c2c87da0 [ 240.246602] r4:ee973014 [ 240.246623] [<c03f3c34>] (spi_sync) from [<c03f0210>] (m25p80_read+0xf8/0x124) [ 240.246641] [<c03f0118>] (m25p80_read) from [<c03f1528>] (spi_nor_read+0x64/0x80) [ 240.246651] r10:00004000 r8:00004000 r7:00000000 r6:00040000 r5:00000000 r4:ee973014 [ 240.246698] [<c03f14c4>] (spi_nor_read) from [<c03cdcb4>] (mtd_read+0x98/0xcc) [ 240.246708] r7:c2c87ea0 r6:ee973098 r5:00000000 r4:001c0000 [ 240.246740] [<c03cdc1c>] (mtd_read) from [<c03d300c>] (mtdchar_read+0xcc/0x204) [ 240.246750] r9:ed424000 r8:00000000 r7:b495d018 r6:c2c87f78 r5:00000000 r4:00040000 [ 240.246793] [<c03d2f40>] (mtdchar_read) from [<c013b1c4>] (__vfs_read+0x3c/0xe0) [ 240.246803] r10:00004000 r9:00000000 r8:c2c87f78 r7:b495d018 r6:c2c87f78 r5:c05c8104 [ 240.246833] r4:c32fe600 [ 240.246852] [<c013b188>] (__vfs_read) from [<c013befc>] (vfs_read+0x98/0x154) [ 240.246861] r10:00000000 r8:00040000 r7:00004000 r6:c2c87f78 r5:b495d018 r4:c32fe600 [ 240.246899] [<c013be64>] (vfs_read) from [<c013c008>] (SyS_read+0x50/0x90) [ 240.246908] r10:00000000 r8:00040000 r7:b495d018 r6:00004000 r5:c32fe601 r4:c32fe600 [ 240.246953] [<c013bfb8>] (SyS_read) from [<c000fa60>] (ret_fast_syscall+0x0/0x3c) [ 240.246962] r9:c2c86000 r8:c000fc04 r7:00000003 r6:00004000 r5:00000000 r4:b495d018 Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-06-21 12:12:54 +00:00
transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
transfer_timeout);
if (!timeout) {
dev_err(&spi->dev, "I/O Error in PIO\n");
spi_imx->devtype_data->reset(spi_imx);
return -ETIMEDOUT;
}
return transfer->len;
}
static int spi_imx_pio_transfer_slave(struct spi_device *spi,
struct spi_transfer *transfer)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
int ret = transfer->len;
if (is_imx53_ecspi(spi_imx) &&
transfer->len > MX53_MAX_TRANSFER_BYTES) {
dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
MX53_MAX_TRANSFER_BYTES);
return -EMSGSIZE;
}
spi_imx->tx_buf = transfer->tx_buf;
spi_imx->rx_buf = transfer->rx_buf;
spi_imx->count = transfer->len;
spi_imx->txfifo = 0;
spi_imx->remainder = 0;
reinit_completion(&spi_imx->xfer_done);
spi_imx->slave_aborted = false;
spi_imx_push(spi_imx);
spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
spi_imx->slave_aborted) {
dev_dbg(&spi->dev, "interrupted\n");
ret = -EINTR;
}
/* ecspi has a HW issue when works in Slave mode,
* after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
* ECSPI_TXDATA keeps shift out the last word data,
* so we have to disable ECSPI when in slave mode after the
* transfer completes
*/
if (spi_imx->devtype_data->disable)
spi_imx->devtype_data->disable(spi_imx);
return ret;
}
static int spi_imx_transfer(struct spi_device *spi,
struct spi_transfer *transfer)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
/* flush rxfifo before transfer */
while (spi_imx->devtype_data->rx_available(spi_imx))
spi: imx: stop buffer overflow in RX FIFO flush Commit 71abd29057cb ("spi: imx: Add support for SPI Slave mode") added an RX FIFO flush before start of a transfer. In slave mode, the master may have sent more data than expected and this data will still be in the RX FIFO at the start of the next transfer, and so needs to be flushed. However, the code to do the flush was accidentally saving this data into the previous transfer's RX buffer, clobbering the contents of whatever followed that buffer. Change it to empty the FIFO and throw away the data. Every one of the RX functions for the different eCSPI versions and modes reads the RX FIFO data using the same readl() call, so just use that, rather than using the spi_imx->rx function pointer and making sure all the different rx functions have a working "throw away" mode. There is another issue, which affects master mode when switching from DMA to PIO. There can be extra data in the RX FIFO which triggers this flush code, causing memory corruption in the same manner. I don't know why this data is unexpectedly in the FIFO. It's likely there is a different bug or erratum responsible for that. But regardless of that, I think this is proper fix the for bug at hand here. Fixes: 71abd29057cb ("spi: imx: Add support for SPI Slave mode") Cc: Jiada Wang <jiada_wang@mentor.com> Cc: Fabio Estevam <festevam@gmail.com> Cc: Stefan Agner <stefan@agner.ch> Cc: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Trent Piepho <tpiepho@impinj.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-03-04 20:18:49 +00:00
readl(spi_imx->base + MXC_CSPIRXDATA);
if (spi_imx->slave_mode)
return spi_imx_pio_transfer_slave(spi, transfer);
if (spi_imx->usedma)
return spi_imx_dma_transfer(spi_imx, transfer);
else
return spi_imx_pio_transfer(spi, transfer);
}
static int spi_imx_setup(struct spi_device *spi)
{
dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
spi->mode, spi->bits_per_word, spi->max_speed_hz);
if (spi->mode & SPI_NO_CS)
return 0;
if (gpio_is_valid(spi->cs_gpio))
gpio_direction_output(spi->cs_gpio,
spi->mode & SPI_CS_HIGH ? 0 : 1);
spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
return 0;
}
static void spi_imx_cleanup(struct spi_device *spi)
{
}
static int
spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
int ret;
ret = clk_enable(spi_imx->clk_per);
if (ret)
return ret;
ret = clk_enable(spi_imx->clk_ipg);
if (ret) {
clk_disable(spi_imx->clk_per);
return ret;
}
ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
if (ret) {
clk_disable(spi_imx->clk_ipg);
clk_disable(spi_imx->clk_per);
}
return ret;
}
static int
spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
clk_disable(spi_imx->clk_ipg);
clk_disable(spi_imx->clk_per);
return 0;
}
static int spi_imx_slave_abort(struct spi_master *master)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
spi_imx->slave_aborted = true;
complete(&spi_imx->xfer_done);
return 0;
}
static int spi_imx_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
const struct of_device_id *of_id =
of_match_device(spi_imx_dt_ids, &pdev->dev);
struct spi_imx_master *mxc_platform_info =
dev_get_platdata(&pdev->dev);
struct spi_master *master;
struct spi_imx_data *spi_imx;
struct resource *res;
int i, ret, irq, spi_drctl;
const struct spi_imx_devtype_data *devtype_data = of_id ? of_id->data :
(struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
bool slave_mode;
if (!np && !mxc_platform_info) {
dev_err(&pdev->dev, "can't get the platform data\n");
return -EINVAL;
}
slave_mode = devtype_data->has_slavemode &&
of_property_read_bool(np, "spi-slave");
if (slave_mode)
master = spi_alloc_slave(&pdev->dev,
sizeof(struct spi_imx_data));
else
master = spi_alloc_master(&pdev->dev,
sizeof(struct spi_imx_data));
if (!master)
return -ENOMEM;
ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
if ((ret < 0) || (spi_drctl >= 0x3)) {
/* '11' is reserved */
spi_drctl = 0;
}
platform_set_drvdata(pdev, master);
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
master->bus_num = np ? -1 : pdev->id;
spi_imx = spi_master_get_devdata(master);
spi_imx->bitbang.master = master;
spi_imx->dev = &pdev->dev;
spi_imx->slave_mode = slave_mode;
spi_imx->devtype_data = devtype_data;
/* Get number of chip selects, either platform data or OF */
if (mxc_platform_info) {
master->num_chipselect = mxc_platform_info->num_chipselect;
if (mxc_platform_info->chipselect) {
treewide: devm_kzalloc() -> devm_kcalloc() The devm_kzalloc() function has a 2-factor argument form, devm_kcalloc(). This patch replaces cases of: devm_kzalloc(handle, a * b, gfp) with: devm_kcalloc(handle, a * b, gfp) as well as handling cases of: devm_kzalloc(handle, a * b * c, gfp) with: devm_kzalloc(handle, array3_size(a, b, c), gfp) as it's slightly less ugly than: devm_kcalloc(handle, array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: devm_kzalloc(handle, 4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. Some manual whitespace fixes were needed in this patch, as Coccinelle really liked to write "=devm_kcalloc..." instead of "= devm_kcalloc...". The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ expression HANDLE; type TYPE; expression THING, E; @@ ( devm_kzalloc(HANDLE, - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | devm_kzalloc(HANDLE, - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression HANDLE; expression COUNT; typedef u8; typedef __u8; @@ ( devm_kzalloc(HANDLE, - sizeof(u8) * (COUNT) + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(__u8) * (COUNT) + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(char) * (COUNT) + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(unsigned char) * (COUNT) + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(u8) * COUNT + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(__u8) * COUNT + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(char) * COUNT + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ expression HANDLE; type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ expression HANDLE; identifier SIZE, COUNT; @@ - devm_kzalloc + devm_kcalloc (HANDLE, - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression HANDLE; expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( devm_kzalloc(HANDLE, - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | devm_kzalloc(HANDLE, - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | devm_kzalloc(HANDLE, - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | devm_kzalloc(HANDLE, - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | devm_kzalloc(HANDLE, - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | devm_kzalloc(HANDLE, - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | devm_kzalloc(HANDLE, - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | devm_kzalloc(HANDLE, - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression HANDLE; expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( devm_kzalloc(HANDLE, - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | devm_kzalloc(HANDLE, - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | devm_kzalloc(HANDLE, - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | devm_kzalloc(HANDLE, - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | devm_kzalloc(HANDLE, - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | devm_kzalloc(HANDLE, - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ expression HANDLE; identifier STRIDE, SIZE, COUNT; @@ ( devm_kzalloc(HANDLE, - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression HANDLE; expression E1, E2, E3; constant C1, C2, C3; @@ ( devm_kzalloc(HANDLE, C1 * C2 * C3, ...) | devm_kzalloc(HANDLE, - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | devm_kzalloc(HANDLE, - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | devm_kzalloc(HANDLE, - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | devm_kzalloc(HANDLE, - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression HANDLE; expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( devm_kzalloc(HANDLE, sizeof(THING) * C2, ...) | devm_kzalloc(HANDLE, sizeof(TYPE) * C2, ...) | devm_kzalloc(HANDLE, C1 * C2 * C3, ...) | devm_kzalloc(HANDLE, C1 * C2, ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - (E1) * E2 + E1, E2 , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - (E1) * (E2) + E1, E2 , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 21:07:58 +00:00
master->cs_gpios = devm_kcalloc(&master->dev,
master->num_chipselect, sizeof(int),
GFP_KERNEL);
if (!master->cs_gpios)
return -ENOMEM;
for (i = 0; i < master->num_chipselect; i++)
master->cs_gpios[i] = mxc_platform_info->chipselect[i];
}
} else {
u32 num_cs;
if (!of_property_read_u32(np, "num-cs", &num_cs))
master->num_chipselect = num_cs;
/* If not preset, default value of 1 is used */
}
spi_imx->bitbang.chipselect = spi_imx_chipselect;
spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
spi_imx->bitbang.master->setup = spi_imx_setup;
spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
| SPI_NO_CS;
if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
is_imx53_ecspi(spi_imx))
spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
spi_imx->spi_drctl = spi_drctl;
init_completion(&spi_imx->xfer_done);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(spi_imx->base)) {
ret = PTR_ERR(spi_imx->base);
goto out_master_put;
}
spi_imx->base_phys = res->start;
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
ret = irq;
goto out_master_put;
}
ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
dev_name(&pdev->dev), spi_imx);
if (ret) {
dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
goto out_master_put;
}
spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
if (IS_ERR(spi_imx->clk_ipg)) {
ret = PTR_ERR(spi_imx->clk_ipg);
goto out_master_put;
}
spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
if (IS_ERR(spi_imx->clk_per)) {
ret = PTR_ERR(spi_imx->clk_per);
goto out_master_put;
}
ret = clk_prepare_enable(spi_imx->clk_per);
if (ret)
goto out_master_put;
ret = clk_prepare_enable(spi_imx->clk_ipg);
if (ret)
goto out_put_per;
spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
/*
* Only validated on i.mx35 and i.mx6 now, can remove the constraint
* if validated on other chips.
*/
if (spi_imx->devtype_data->has_dmamode) {
ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
if (ret == -EPROBE_DEFER)
goto out_clk_put;
if (ret < 0)
dev_err(&pdev->dev, "dma setup error %d, use pio\n",
ret);
}
spi_imx->devtype_data->reset(spi_imx);
spi_imx->devtype_data->intctrl(spi_imx, 0);
master->dev.of_node = pdev->dev.of_node;
ret = spi_bitbang_start(&spi_imx->bitbang);
if (ret) {
dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
goto out_clk_put;
}
/* Request GPIO CS lines, if any */
if (!spi_imx->slave_mode && master->cs_gpios) {
for (i = 0; i < master->num_chipselect; i++) {
if (!gpio_is_valid(master->cs_gpios[i]))
continue;
ret = devm_gpio_request(&pdev->dev,
master->cs_gpios[i],
DRIVER_NAME);
if (ret) {
dev_err(&pdev->dev, "Can't get CS GPIO %i\n",
master->cs_gpios[i]);
goto out_spi_bitbang;
}
}
}
dev_info(&pdev->dev, "probed\n");
clk_disable(spi_imx->clk_ipg);
clk_disable(spi_imx->clk_per);
return ret;
out_spi_bitbang:
spi_bitbang_stop(&spi_imx->bitbang);
out_clk_put:
clk_disable_unprepare(spi_imx->clk_ipg);
out_put_per:
clk_disable_unprepare(spi_imx->clk_per);
out_master_put:
spi_master_put(master);
return ret;
}
static int spi_imx_remove(struct platform_device *pdev)
{
struct spi_master *master = platform_get_drvdata(pdev);
struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
int ret;
spi_bitbang_stop(&spi_imx->bitbang);
ret = clk_enable(spi_imx->clk_per);
if (ret)
return ret;
ret = clk_enable(spi_imx->clk_ipg);
if (ret) {
clk_disable(spi_imx->clk_per);
return ret;
}
writel(0, spi_imx->base + MXC_CSPICTRL);
clk_disable_unprepare(spi_imx->clk_ipg);
clk_disable_unprepare(spi_imx->clk_per);
spi_imx_sdma_exit(spi_imx);
spi_master_put(master);
return 0;
}
static struct platform_driver spi_imx_driver = {
.driver = {
.name = DRIVER_NAME,
.of_match_table = spi_imx_dt_ids,
},
.id_table = spi_imx_devtype,
.probe = spi_imx_probe,
.remove = spi_imx_remove,
};
module_platform_driver(spi_imx_driver);
MODULE_DESCRIPTION("SPI Controller driver");
MODULE_AUTHOR("Sascha Hauer, Pengutronix");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRIVER_NAME);