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path: root/drivers/spi/spi-imx.c
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Diffstat (limited to 'drivers/spi/spi-imx.c')
-rw-r--r--drivers/spi/spi-imx.c256
1 files changed, 214 insertions, 42 deletions
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index babb15f07995..79ddefe4180d 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -53,10 +53,13 @@
/* 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,
@@ -76,7 +79,9 @@ struct spi_imx_devtype_data {
void (*trigger)(struct spi_imx_data *);
int (*rx_available)(struct spi_imx_data *);
void (*reset)(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;
@@ -108,6 +113,11 @@ struct spi_imx_data {
unsigned int dynamic_burst, read_u32;
unsigned int word_mask;
+ /* Slave mode */
+ bool slave_mode;
+ bool slave_aborted;
+ unsigned int slave_burst;
+
/* DMA */
bool usedma;
u32 wml;
@@ -221,6 +231,9 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
if (!master->dma_rx)
return false;
+ if (spi_imx->slave_mode)
+ return false;
+
bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
if (bytes_per_word != 1 && bytes_per_word != 2 && bytes_per_word != 4)
@@ -262,6 +275,7 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
#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)
@@ -378,6 +392,44 @@ static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
spi_imx_buf_tx_u16(spi_imx);
}
+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;
+ }
+}
+
+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)
@@ -427,6 +479,9 @@ static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
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);
}
@@ -439,6 +494,15 @@ static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
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_config(struct spi_device *spi)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
@@ -446,14 +510,11 @@ static int mx51_ecspi_config(struct spi_device *spi)
u32 clk = spi_imx->speed_hz, delay, reg;
u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
- /*
- * The hardware seems to have a race condition when changing modes. The
- * current assumption is that the selection of the channel arrives
- * earlier in the hardware than the mode bits when they are written at
- * the same time.
- * So set master mode for all channels as we do not support slave mode.
- */
- ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
+ /* 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).
@@ -468,9 +529,22 @@ static int mx51_ecspi_config(struct spi_device *spi)
/* set chip select to use */
ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
- ctrl |= (spi_imx->bits_per_word - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
+ 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;
- cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
+ /*
+ * 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);
@@ -805,6 +879,7 @@ static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
.fifo_size = 8,
.has_dmamode = false,
.dynamic_burst = false,
+ .has_slavemode = false,
.devtype = IMX1_CSPI,
};
@@ -817,6 +892,7 @@ static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
.fifo_size = 8,
.has_dmamode = false,
.dynamic_burst = false,
+ .has_slavemode = false,
.devtype = IMX21_CSPI,
};
@@ -830,6 +906,7 @@ static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
.fifo_size = 8,
.has_dmamode = false,
.dynamic_burst = false,
+ .has_slavemode = false,
.devtype = IMX27_CSPI,
};
@@ -842,6 +919,7 @@ static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
.fifo_size = 8,
.has_dmamode = false,
.dynamic_burst = false,
+ .has_slavemode = false,
.devtype = IMX31_CSPI,
};
@@ -855,6 +933,7 @@ static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
.fifo_size = 8,
.has_dmamode = true,
.dynamic_burst = false,
+ .has_slavemode = false,
.devtype = IMX35_CSPI,
};
@@ -867,6 +946,8 @@ static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
.fifo_size = 64,
.has_dmamode = true,
.dynamic_burst = true,
+ .has_slavemode = true,
+ .disable = mx51_ecspi_disable,
.devtype = IMX51_ECSPI,
};
@@ -878,6 +959,8 @@ static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
.reset = mx51_ecspi_reset,
.fifo_size = 64,
.has_dmamode = true,
+ .has_slavemode = true,
+ .disable = mx51_ecspi_disable,
.devtype = IMX53_ECSPI,
};
@@ -945,14 +1028,16 @@ static void spi_imx_push(struct spi_imx_data *spi_imx)
spi_imx->txfifo++;
}
- spi_imx->devtype_data->trigger(spi_imx);
+ 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->devtype_data->rx_available(spi_imx)) {
+ while (spi_imx->txfifo &&
+ spi_imx->devtype_data->rx_available(spi_imx)) {
spi_imx->rx(spi_imx);
spi_imx->txfifo--;
}
@@ -1034,7 +1119,7 @@ static int spi_imx_setupxfer(struct spi_device *spi,
spi_imx->speed_hz = t->speed_hz;
/* Initialize the functions for transfer */
- if (spi_imx->devtype_data->dynamic_burst) {
+ if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode) {
u32 mask;
spi_imx->dynamic_burst = 0;
@@ -1078,6 +1163,12 @@ static int spi_imx_setupxfer(struct spi_device *spi,
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;
+ spi_imx->slave_burst = t->len;
+ }
+
spi_imx->devtype_data->config(spi);
return 0;
@@ -1262,11 +1353,61 @@ static int spi_imx_pio_transfer(struct spi_device *spi,
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;
+
+ 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->rx(spi_imx);
+
+ 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
@@ -1323,6 +1464,16 @@ spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
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;
@@ -1334,13 +1485,23 @@ static int spi_imx_probe(struct platform_device *pdev)
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;
}
- master = spi_alloc_master(&pdev->dev, sizeof(struct spi_imx_data));
+ 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;
@@ -1358,20 +1519,29 @@ static int spi_imx_probe(struct platform_device *pdev)
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 = of_id ? of_id->data :
- (struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
+ 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;
- master->cs_gpios = devm_kzalloc(&master->dev,
- sizeof(int) * master->num_chipselect, GFP_KERNEL);
- if (!master->cs_gpios)
- return -ENOMEM;
+ if (mxc_platform_info->chipselect) {
+ master->cs_gpios = devm_kzalloc(&master->dev,
+ sizeof(int) * master->num_chipselect, 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;
- for (i = 0; i < master->num_chipselect; i++)
- master->cs_gpios[i] = mxc_platform_info->chipselect[i];
- }
+ 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;
@@ -1380,6 +1550,7 @@ static int spi_imx_probe(struct platform_device *pdev)
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) ||
@@ -1451,37 +1622,38 @@ static int spi_imx_probe(struct platform_device *pdev)
spi_imx->devtype_data->intctrl(spi_imx, 0);
master->dev.of_node = pdev->dev.of_node;
+
+ /* 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;
+ }
+ }
+ }
+
ret = spi_bitbang_start(&spi_imx->bitbang);
if (ret) {
dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
goto out_clk_put;
}
- if (!master->cs_gpios) {
- dev_err(&pdev->dev, "No CS GPIOs available\n");
- ret = -EINVAL;
- goto out_clk_put;
- }
-
- 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_clk_put;
- }
- }
-
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:

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