aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/spi/spi-imx.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/spi/spi-imx.c')
-rw-r--r--drivers/spi/spi-imx.c178
1 files changed, 127 insertions, 51 deletions
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index 5b6f3655c366..0078cb365d8c 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -59,10 +59,12 @@ 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 (*config)(struct spi_device *);
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;
@@ -216,7 +218,6 @@ 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);
- unsigned int bytes_per_word, i;
if (!master->dma_rx)
return false;
@@ -224,19 +225,23 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
if (spi_imx->slave_mode)
return false;
- 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 (!(transfer->len % (i * bytes_per_word)))
- break;
- }
-
- spi_imx->wml = i;
spi_imx->dynamic_burst = 0;
return true;
}
+/*
+ * Note the number of natively supported chip selects for MX51 is 4. Some
+ * devices may have less actual SS pins but the register map supports 4. When
+ * using gpio chip selects the cs values passed into the macros below can go
+ * outside the range 0 - 3. We therefore need to limit the cs value to avoid
+ * corrupting bits outside the allocated locations.
+ *
+ * The simplest way to do this is to just mask the cs bits to 2 bits. This
+ * still allows all 4 native chip selects to work as well as gpio chip selects
+ * (which can use any of the 4 chip select configurations).
+ */
+
#define MX51_ECSPI_CTRL 0x08
#define MX51_ECSPI_CTRL_ENABLE (1 << 0)
#define MX51_ECSPI_CTRL_XCH (1 << 2)
@@ -245,16 +250,16 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
#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_CS(cs) ((cs & 3) << 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_CONFIG_SCLKPHA(cs) (1 << ((cs & 3) + 0))
+#define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs & 3) + 4))
+#define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs & 3) + 8))
+#define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs & 3) + 12))
+#define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs & 3) + 20))
#define MX51_ECSPI_INT 0x10
#define MX51_ECSPI_INT_TEEN (1 << 0)
@@ -429,8 +434,7 @@ static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
unsigned int pre, post;
unsigned int fin = spi_imx->spi_clk;
- if (unlikely(fspi > fin))
- return 0;
+ fspi = min(fspi, fin);
post = fls(fin) - fls(fspi);
if (fin > fspi << post)
@@ -491,11 +495,12 @@ static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
}
-static int mx51_ecspi_config(struct spi_device *spi)
+static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
+ struct spi_message *msg)
{
- struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
+ struct spi_device *spi = msg->spi;
u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
- u32 clk = spi_imx->speed_hz, delay, reg;
+ u32 testreg;
u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
/* set Master or Slave mode */
@@ -510,19 +515,21 @@ static int mx51_ecspi_config(struct spi_device *spi)
if (spi->mode & SPI_READY)
ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
- /* set clock speed */
- ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->speed_hz, &clk);
- spi_imx->spi_bus_clk = clk;
-
/* set chip select to use */
ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
- if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
- ctrl |= (spi_imx->slave_burst * 8 - 1)
- << MX51_ECSPI_CTRL_BL_OFFSET;
+ /*
+ * 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
- ctrl |= (spi_imx->bits_per_word - 1)
- << MX51_ECSPI_CTRL_BL_OFFSET;
+ testreg &= ~MX51_ECSPI_TESTREG_LBC;
+ writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
/*
* eCSPI burst completion by Chip Select signal in Slave mode
@@ -546,25 +553,42 @@ static int mx51_ecspi_config(struct spi_device *spi)
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);
- if (spi_imx->usedma)
- ctrl |= MX51_ECSPI_CTRL_SMC;
+ writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
- /* CTRL register always go first to bring out controller from reset */
- writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
+ return 0;
+}
- reg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
- if (spi->mode & SPI_LOOP)
- reg |= MX51_ECSPI_TESTREG_LBC;
+static int mx51_ecspi_config(struct spi_device *spi)
+{
+ struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
+ u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
+ u32 clk = spi_imx->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
- reg &= ~MX51_ECSPI_TESTREG_LBC;
- writel(reg, spi_imx->base + MX51_ECSPI_TESTREG);
+ ctrl |= (spi_imx->bits_per_word - 1)
+ << MX51_ECSPI_CTRL_BL_OFFSET;
- writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
+ /* set clock speed */
+ ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
+ 0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
+ ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->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);
/*
* Wait until the changes in the configuration register CONFIGREG
@@ -583,18 +607,20 @@ static int mx51_ecspi_config(struct spi_device *spi)
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) |
+ 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);
-
- return 0;
}
static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
@@ -661,6 +687,12 @@ static void mx31_trigger(struct spi_imx_data *spi_imx)
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_config(struct spi_device *spi)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
@@ -757,6 +789,12 @@ static void mx21_trigger(struct spi_imx_data *spi_imx)
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_config(struct spi_device *spi)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
@@ -826,6 +864,12 @@ static void mx1_trigger(struct spi_imx_data *spi_imx)
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_config(struct spi_device *spi)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
@@ -860,6 +904,7 @@ static void mx1_reset(struct spi_imx_data *spi_imx)
static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
.intctrl = mx1_intctrl,
+ .prepare_message = mx1_prepare_message,
.config = mx1_config,
.trigger = mx1_trigger,
.rx_available = mx1_rx_available,
@@ -873,6 +918,7 @@ static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
.intctrl = mx21_intctrl,
+ .prepare_message = mx21_prepare_message,
.config = mx21_config,
.trigger = mx21_trigger,
.rx_available = mx21_rx_available,
@@ -887,6 +933,7 @@ static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
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,
.config = mx21_config,
.trigger = mx21_trigger,
.rx_available = mx21_rx_available,
@@ -900,6 +947,7 @@ static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
.intctrl = mx31_intctrl,
+ .prepare_message = mx31_prepare_message,
.config = mx31_config,
.trigger = mx31_trigger,
.rx_available = mx31_rx_available,
@@ -914,6 +962,7 @@ static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
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,
.config = mx31_config,
.trigger = mx31_trigger,
.rx_available = mx31_rx_available,
@@ -927,10 +976,12 @@ static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
.intctrl = mx51_ecspi_intctrl,
+ .prepare_message = mx51_ecspi_prepare_message,
.config = mx51_ecspi_config,
.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,
@@ -941,6 +992,7 @@ static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
.intctrl = mx51_ecspi_intctrl,
+ .prepare_message = mx51_ecspi_prepare_message,
.config = mx51_ecspi_config,
.trigger = mx51_ecspi_trigger,
.rx_available = mx51_ecspi_rx_available,
@@ -1138,7 +1190,6 @@ 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);
- int ret;
if (!t)
return 0;
@@ -1179,12 +1230,6 @@ static int spi_imx_setupxfer(struct spi_device *spi,
else
spi_imx->usedma = 0;
- if (spi_imx->usedma) {
- ret = spi_imx_dma_configure(spi->master);
- if (ret)
- return ret;
- }
-
if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
spi_imx->rx = mx53_ecspi_rx_slave;
spi_imx->tx = mx53_ecspi_tx_slave;
@@ -1289,6 +1334,31 @@ static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
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
@@ -1475,7 +1545,13 @@ spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
return ret;
}
- return 0;
+ 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