diff options
| -rw-r--r-- | Documentation/devicetree/bindings/spi/spi-davinci.txt | 9 | ||||
| -rw-r--r-- | drivers/spi/spi-davinci.c | 64 |
2 files changed, 64 insertions, 9 deletions
diff --git a/Documentation/devicetree/bindings/spi/spi-davinci.txt b/Documentation/devicetree/bindings/spi/spi-davinci.txt index 6d0ac8d0ad9b..f80887bca0d6 100644 --- a/Documentation/devicetree/bindings/spi/spi-davinci.txt +++ b/Documentation/devicetree/bindings/spi/spi-davinci.txt @@ -8,7 +8,8 @@ Required properties: - "ti,dm6441-spi" for SPI used similar to that on DM644x SoC family - "ti,da830-spi" for SPI used similar to that on DA8xx SoC family - reg: Offset and length of SPI controller register space -- num-cs: Number of chip selects +- num-cs: Number of chip selects. This includes internal as well as + GPIO chip selects. - ti,davinci-spi-intr-line: interrupt line used to connect the SPI IP to the interrupt controller within the SoC. Possible values are 0 and 1. Manual says one of the two possible interrupt @@ -17,6 +18,12 @@ Required properties: - interrupts: interrupt number mapped to CPU. - clocks: spi clk phandle +Optional: +- cs-gpios: gpio chip selects + For example to have 3 internal CS and 2 GPIO CS, user could define + cs-gpios = <0>, <0>, <0>, <&gpio1 30 0>, <&gpio1 31 0>; + where first three are internal CS and last two are GPIO CS. + Example of a NOR flash slave device (n25q032) connected to DaVinci SPI controller device over the SPI bus. diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c index 2477af4bc1c7..ac4414e00bb9 100644 --- a/drivers/spi/spi-davinci.c +++ b/drivers/spi/spi-davinci.c @@ -30,6 +30,7 @@ #include <linux/edma.h> #include <linux/of.h> #include <linux/of_device.h> +#include <linux/of_gpio.h> #include <linux/spi/spi.h> #include <linux/spi/spi_bitbang.h> #include <linux/slab.h> @@ -207,17 +208,28 @@ static inline void clear_io_bits(void __iomem *addr, u32 bits) static void davinci_spi_chipselect(struct spi_device *spi, int value) { struct davinci_spi *dspi; + struct device_node *np = spi->dev.of_node; struct davinci_spi_platform_data *pdata; + struct spi_master *master = spi->master; u8 chip_sel = spi->chip_select; u16 spidat1 = CS_DEFAULT; bool gpio_chipsel = false; + int gpio; dspi = spi_master_get_devdata(spi->master); pdata = &dspi->pdata; - if (pdata->chip_sel && chip_sel < pdata->num_chipselect && - pdata->chip_sel[chip_sel] != SPI_INTERN_CS) + if (np && master->cs_gpios != NULL && spi->cs_gpio >= 0) { + /* SPI core parse and update master->cs_gpio */ gpio_chipsel = true; + gpio = spi->cs_gpio; + } else if (pdata->chip_sel && + chip_sel < pdata->num_chipselect && + pdata->chip_sel[chip_sel] != SPI_INTERN_CS) { + /* platform data defines chip_sel */ + gpio_chipsel = true; + gpio = pdata->chip_sel[chip_sel]; + } /* * Board specific chip select logic decides the polarity and cs @@ -225,9 +237,9 @@ static void davinci_spi_chipselect(struct spi_device *spi, int value) */ if (gpio_chipsel) { if (value == BITBANG_CS_ACTIVE) - gpio_set_value(pdata->chip_sel[chip_sel], 0); + gpio_set_value(gpio, 0); else - gpio_set_value(pdata->chip_sel[chip_sel], 1); + gpio_set_value(gpio, 1); } else { if (value == BITBANG_CS_ACTIVE) { spidat1 |= SPIDAT1_CSHOLD_MASK; @@ -390,17 +402,41 @@ static int davinci_spi_setup(struct spi_device *spi) int retval = 0; struct davinci_spi *dspi; struct davinci_spi_platform_data *pdata; + struct spi_master *master = spi->master; + struct device_node *np = spi->dev.of_node; + bool internal_cs = true; dspi = spi_master_get_devdata(spi->master); pdata = &dspi->pdata; if (!(spi->mode & SPI_NO_CS)) { - if ((pdata->chip_sel == NULL) || - (pdata->chip_sel[spi->chip_select] == SPI_INTERN_CS)) - set_io_bits(dspi->base + SPIPC0, 1 << spi->chip_select); - + if (np && (master->cs_gpios != NULL) && (spi->cs_gpio >= 0)) { + unsigned long flags; + + flags = GPIOF_DIR_OUT; + if (spi->mode & SPI_CS_HIGH) + flags |= GPIOF_INIT_LOW; + else + flags |= GPIOF_INIT_HIGH; + retval = gpio_request_one(spi->cs_gpio, + flags, dev_name(&spi->dev)); + if (retval) { + dev_err(&spi->dev, + "GPIO %d request failed (%d)\n", + spi->cs_gpio, retval); + return retval; + } + internal_cs = false; + } else if (pdata->chip_sel && + spi->chip_select < pdata->num_chipselect && + pdata->chip_sel[spi->chip_select] != SPI_INTERN_CS) { + internal_cs = false; + } } + 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); @@ -412,6 +448,15 @@ static int davinci_spi_setup(struct spi_device *spi) return retval; } +static void davinci_spi_cleanup(struct spi_device *spi) +{ + struct spi_master *master = spi->master; + struct device_node *np = spi->dev.of_node; + + if (np && (master->cs_gpios != NULL) && (spi->cs_gpio >= 0)) + gpio_free(spi->cs_gpio); +} + static int davinci_spi_check_error(struct davinci_spi *dspi, int int_status) { struct device *sdev = dspi->bitbang.master->dev.parent; @@ -810,6 +855,8 @@ static int spi_davinci_get_pdata(struct platform_device *pdev, /* * default num_cs is 1 and all chipsel are internal to the chip + * indicated by chip_sel being NULL or cs_gpios being NULL or + * set to -ENOENT. num-cs includes internal as well as gpios. * indicated by chip_sel being NULL. GPIO based CS is not * supported yet in DT bindings. */ @@ -921,6 +968,7 @@ static int davinci_spi_probe(struct platform_device *pdev) master->num_chipselect = pdata->num_chipselect; master->bits_per_word_mask = SPI_BPW_RANGE_MASK(2, 16); master->setup = davinci_spi_setup; + master->cleanup = davinci_spi_cleanup; dspi->bitbang.chipselect = davinci_spi_chipselect; dspi->bitbang.setup_transfer = davinci_spi_setup_transfer; |