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path: root/drivers/spi/spi-davinci.c
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Diffstat (limited to 'drivers/spi/spi-davinci.c')
-rw-r--r--drivers/spi/spi-davinci.c108
1 files changed, 82 insertions, 26 deletions
diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c
index 276a3884fb3c..63700ab7bd9f 100644
--- a/drivers/spi/spi-davinci.c
+++ b/drivers/spi/spi-davinci.c
@@ -65,6 +65,7 @@
/* SPIDAT1 (upper 16 bit defines) */
#define SPIDAT1_CSHOLD_MASK BIT(12)
+#define SPIDAT1_WDEL BIT(10)
/* SPIGCR1 */
#define SPIGCR1_CLKMOD_MASK BIT(1)
@@ -167,8 +168,10 @@ static void davinci_spi_rx_buf_u16(u32 data, struct davinci_spi *dspi)
static u32 davinci_spi_tx_buf_u8(struct davinci_spi *dspi)
{
u32 data = 0;
+
if (dspi->tx) {
const u8 *tx = dspi->tx;
+
data = *tx++;
dspi->tx = tx;
}
@@ -178,8 +181,10 @@ static u32 davinci_spi_tx_buf_u8(struct davinci_spi *dspi)
static u32 davinci_spi_tx_buf_u16(struct davinci_spi *dspi)
{
u32 data = 0;
+
if (dspi->tx) {
const u16 *tx = dspi->tx;
+
data = *tx++;
dspi->tx = tx;
}
@@ -209,6 +214,7 @@ static void davinci_spi_chipselect(struct spi_device *spi, int value)
{
struct davinci_spi *dspi;
struct davinci_spi_platform_data *pdata;
+ struct davinci_spi_config *spicfg = spi->controller_data;
u8 chip_sel = spi->chip_select;
u16 spidat1 = CS_DEFAULT;
bool gpio_chipsel = false;
@@ -223,6 +229,10 @@ static void davinci_spi_chipselect(struct spi_device *spi, int value)
gpio = spi->cs_gpio;
}
+ /* program delay transfers if tx_delay is non zero */
+ if (spicfg->wdelay)
+ spidat1 |= SPIDAT1_WDEL;
+
/*
* Board specific chip select logic decides the polarity and cs
* line for the controller
@@ -237,9 +247,9 @@ static void davinci_spi_chipselect(struct spi_device *spi, int value)
spidat1 |= SPIDAT1_CSHOLD_MASK;
spidat1 &= ~(0x1 << chip_sel);
}
-
- iowrite16(spidat1, dspi->base + SPIDAT1 + 2);
}
+
+ iowrite16(spidat1, dspi->base + SPIDAT1 + 2);
}
/**
@@ -285,7 +295,7 @@ static int davinci_spi_setup_transfer(struct spi_device *spi,
int prescale;
dspi = spi_master_get_devdata(spi->master);
- spicfg = (struct davinci_spi_config *)spi->controller_data;
+ spicfg = spi->controller_data;
if (!spicfg)
spicfg = &davinci_spi_default_cfg;
@@ -333,6 +343,14 @@ static int davinci_spi_setup_transfer(struct spi_device *spi,
spifmt |= SPIFMT_PHASE_MASK;
/*
+ * Assume wdelay is used only on SPI peripherals that has this field
+ * in SPIFMTn register and when it's configured from board file or DT.
+ */
+ if (spicfg->wdelay)
+ spifmt |= ((spicfg->wdelay << SPIFMT_WDELAY_SHIFT)
+ & SPIFMT_WDELAY_MASK);
+
+ /*
* Version 1 hardware supports two basic SPI modes:
* - Standard SPI mode uses 4 pins, with chipselect
* - 3 pin SPI is a 4 pin variant without CS (SPI_NO_CS)
@@ -349,9 +367,6 @@ static int davinci_spi_setup_transfer(struct spi_device *spi,
u32 delay = 0;
- spifmt |= ((spicfg->wdelay << SPIFMT_WDELAY_SHIFT)
- & SPIFMT_WDELAY_MASK);
-
if (spicfg->odd_parity)
spifmt |= SPIFMT_ODD_PARITY_MASK;
@@ -383,6 +398,26 @@ static int davinci_spi_setup_transfer(struct spi_device *spi,
return 0;
}
+static int davinci_spi_of_setup(struct spi_device *spi)
+{
+ struct davinci_spi_config *spicfg = spi->controller_data;
+ struct device_node *np = spi->dev.of_node;
+ u32 prop;
+
+ if (spicfg == NULL && np) {
+ spicfg = kzalloc(sizeof(*spicfg), GFP_KERNEL);
+ if (!spicfg)
+ return -ENOMEM;
+ *spicfg = davinci_spi_default_cfg;
+ /* override with dt configured values */
+ if (!of_property_read_u32(np, "ti,spi-wdelay", &prop))
+ spicfg->wdelay = (u8)prop;
+ spi->controller_data = spicfg;
+ }
+
+ return 0;
+}
+
/**
* davinci_spi_setup - This functions will set default transfer method
* @spi: spi device on which data transfer to be done
@@ -397,36 +432,33 @@ static int davinci_spi_setup(struct spi_device *spi)
struct spi_master *master = spi->master;
struct device_node *np = spi->dev.of_node;
bool internal_cs = true;
- unsigned long flags = GPIOF_DIR_OUT;
dspi = spi_master_get_devdata(spi->master);
pdata = &dspi->pdata;
- flags |= (spi->mode & SPI_CS_HIGH) ? GPIOF_INIT_LOW : GPIOF_INIT_HIGH;
-
if (!(spi->mode & SPI_NO_CS)) {
if (np && (master->cs_gpios != NULL) && (spi->cs_gpio >= 0)) {
- retval = gpio_request_one(spi->cs_gpio,
- flags, dev_name(&spi->dev));
+ retval = gpio_direction_output(
+ spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
internal_cs = false;
} else if (pdata->chip_sel &&
spi->chip_select < pdata->num_chipselect &&
pdata->chip_sel[spi->chip_select] != SPI_INTERN_CS) {
spi->cs_gpio = pdata->chip_sel[spi->chip_select];
- retval = gpio_request_one(spi->cs_gpio,
- flags, dev_name(&spi->dev));
+ retval = gpio_direction_output(
+ spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
internal_cs = false;
}
- }
- if (retval) {
- dev_err(&spi->dev, "GPIO %d setup failed (%d)\n",
- spi->cs_gpio, retval);
- return retval;
- }
+ if (retval) {
+ dev_err(&spi->dev, "GPIO %d setup failed (%d)\n",
+ spi->cs_gpio, retval);
+ return retval;
+ }
- if (internal_cs)
- set_io_bits(dspi->base + SPIPC0, 1 << spi->chip_select);
+ if (internal_cs)
+ set_io_bits(dspi->base + SPIPC0, 1 << spi->chip_select);
+ }
if (spi->mode & SPI_READY)
set_io_bits(dspi->base + SPIPC0, SPIPC0_SPIENA_MASK);
@@ -436,13 +468,16 @@ static int davinci_spi_setup(struct spi_device *spi)
else
clear_io_bits(dspi->base + SPIGCR1, SPIGCR1_LOOPBACK_MASK);
- return retval;
+ return davinci_spi_of_setup(spi);
}
static void davinci_spi_cleanup(struct spi_device *spi)
{
- if (spi->cs_gpio >= 0)
- gpio_free(spi->cs_gpio);
+ struct davinci_spi_config *spicfg = spi->controller_data;
+
+ spi->controller_data = NULL;
+ if (spi->dev.of_node)
+ kfree(spicfg);
}
static int davinci_spi_check_error(struct davinci_spi *dspi, int int_status)
@@ -967,6 +1002,27 @@ static int davinci_spi_probe(struct platform_device *pdev)
if (dspi->version == SPI_VERSION_2)
dspi->bitbang.flags |= SPI_READY;
+ if (pdev->dev.of_node) {
+ int i;
+
+ for (i = 0; i < pdata->num_chipselect; i++) {
+ int cs_gpio = of_get_named_gpio(pdev->dev.of_node,
+ "cs-gpios", i);
+
+ if (cs_gpio == -EPROBE_DEFER) {
+ ret = cs_gpio;
+ goto free_clk;
+ }
+
+ if (gpio_is_valid(cs_gpio)) {
+ ret = devm_gpio_request(&pdev->dev, cs_gpio,
+ dev_name(&pdev->dev));
+ if (ret)
+ goto free_clk;
+ }
+ }
+ }
+
r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
if (r)
dma_rx_chan = r->start;
@@ -985,8 +1041,8 @@ static int davinci_spi_probe(struct platform_device *pdev)
goto free_clk;
dev_info(&pdev->dev, "DMA: supported\n");
- dev_info(&pdev->dev, "DMA: RX channel: %pa, TX channel: %pa, "
- "event queue: %d\n", &dma_rx_chan, &dma_tx_chan,
+ dev_info(&pdev->dev, "DMA: RX channel: %pa, TX channel: %pa, event queue: %d\n",
+ &dma_rx_chan, &dma_tx_chan,
pdata->dma_event_q);
}
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.