diff options
Diffstat (limited to 'drivers/spi/spi-gpio.c')
| -rw-r--r-- | drivers/spi/spi-gpio.c | 131 |
1 files changed, 119 insertions, 12 deletions
diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c index 0b56cfc71fab..a2b50c516b31 100644 --- a/drivers/spi/spi-gpio.c +++ b/drivers/spi/spi-gpio.c @@ -22,6 +22,8 @@ #include <linux/init.h> #include <linux/platform_device.h> #include <linux/gpio.h> +#include <linux/of_device.h> +#include <linux/of_gpio.h> #include <linux/spi/spi.h> #include <linux/spi/spi_bitbang.h> @@ -46,6 +48,7 @@ struct spi_gpio { struct spi_bitbang bitbang; struct spi_gpio_platform_data pdata; struct platform_device *pdev; + int cs_gpios[0]; }; /*----------------------------------------------------------------------*/ @@ -89,15 +92,21 @@ struct spi_gpio { /*----------------------------------------------------------------------*/ -static inline const struct spi_gpio_platform_data * __pure -spi_to_pdata(const struct spi_device *spi) +static inline struct spi_gpio * __pure +spi_to_spi_gpio(const struct spi_device *spi) { const struct spi_bitbang *bang; - const struct spi_gpio *spi_gpio; + struct spi_gpio *spi_gpio; bang = spi_master_get_devdata(spi->master); spi_gpio = container_of(bang, struct spi_gpio, bitbang); - return &spi_gpio->pdata; + return spi_gpio; +} + +static inline struct spi_gpio_platform_data * __pure +spi_to_pdata(const struct spi_device *spi) +{ + return &spi_to_spi_gpio(spi)->pdata; } /* this is #defined to avoid unused-variable warnings when inlining */ @@ -210,7 +219,8 @@ static u32 spi_gpio_spec_txrx_word_mode3(struct spi_device *spi, static void spi_gpio_chipselect(struct spi_device *spi, int is_active) { - unsigned long cs = (unsigned long) spi->controller_data; + struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi); + unsigned int cs = spi_gpio->cs_gpios[spi->chip_select]; /* set initial clock polarity */ if (is_active) @@ -224,12 +234,27 @@ static void spi_gpio_chipselect(struct spi_device *spi, int is_active) static int spi_gpio_setup(struct spi_device *spi) { - unsigned long cs = (unsigned long) spi->controller_data; - int status = 0; + unsigned int cs; + int status = 0; + struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi); + struct device_node *np = spi->master->dev.of_node; if (spi->bits_per_word > 32) return -EINVAL; + if (np) { + /* + * In DT environments, the CS GPIOs have already been + * initialized from the "cs-gpios" property of the node. + */ + cs = spi_gpio->cs_gpios[spi->chip_select]; + } else { + /* + * ... otherwise, take it from spi->controller_data + */ + cs = (unsigned int) spi->controller_data; + } + if (!spi->controller_state) { if (cs != SPI_GPIO_NO_CHIPSELECT) { status = gpio_request(cs, dev_name(&spi->dev)); @@ -239,8 +264,12 @@ static int spi_gpio_setup(struct spi_device *spi) !(spi->mode & SPI_CS_HIGH)); } } - if (!status) + if (!status) { status = spi_bitbang_setup(spi); + /* in case it was initialized from static board data */ + spi_gpio->cs_gpios[spi->chip_select] = cs; + } + if (status) { if (!spi->controller_state && cs != SPI_GPIO_NO_CHIPSELECT) gpio_free(cs); @@ -250,7 +279,8 @@ static int spi_gpio_setup(struct spi_device *spi) static void spi_gpio_cleanup(struct spi_device *spi) { - unsigned long cs = (unsigned long) spi->controller_data; + struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi); + unsigned int cs = spi_gpio->cs_gpios[spi->chip_select]; if (cs != SPI_GPIO_NO_CHIPSELECT) gpio_free(cs); @@ -313,6 +343,55 @@ done: return value; } +#ifdef CONFIG_OF +static struct of_device_id spi_gpio_dt_ids[] = { + { .compatible = "spi-gpio" }, + {} +}; +MODULE_DEVICE_TABLE(of, spi_gpio_dt_ids); + +static int spi_gpio_probe_dt(struct platform_device *pdev) +{ + int ret; + u32 tmp; + struct spi_gpio_platform_data *pdata; + struct device_node *np = pdev->dev.of_node; + const struct of_device_id *of_id = + of_match_device(spi_gpio_dt_ids, &pdev->dev); + + if (!of_id) + return 0; + + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return -ENOMEM; + + pdata->sck = of_get_named_gpio(np, "gpio-sck", 0); + pdata->miso = of_get_named_gpio(np, "gpio-miso", 0); + pdata->mosi = of_get_named_gpio(np, "gpio-mosi", 0); + + ret = of_property_read_u32(np, "num-chipselects", &tmp); + if (ret < 0) { + dev_err(&pdev->dev, "num-chipselects property not found\n"); + goto error_free; + } + + pdata->num_chipselect = tmp; + pdev->dev.platform_data = pdata; + + return 1; + +error_free: + devm_kfree(&pdev->dev, pdata); + return ret; +} +#else +static inline int spi_gpio_probe_dt(struct platform_device *pdev) +{ + return 0; +} +#endif + static int __devinit spi_gpio_probe(struct platform_device *pdev) { int status; @@ -320,6 +399,13 @@ static int __devinit spi_gpio_probe(struct platform_device *pdev) struct spi_gpio *spi_gpio; struct spi_gpio_platform_data *pdata; u16 master_flags = 0; + bool use_of = 0; + + status = spi_gpio_probe_dt(pdev); + if (status < 0) + return status; + if (status > 0) + use_of = 1; pdata = pdev->dev.platform_data; #ifdef GENERIC_BITBANG @@ -331,7 +417,8 @@ static int __devinit spi_gpio_probe(struct platform_device *pdev) if (status < 0) return status; - master = spi_alloc_master(&pdev->dev, sizeof *spi_gpio); + master = spi_alloc_master(&pdev->dev, sizeof(*spi_gpio) + + (sizeof(int) * SPI_N_CHIPSEL)); if (!master) { status = -ENOMEM; goto gpio_free; @@ -348,6 +435,23 @@ static int __devinit spi_gpio_probe(struct platform_device *pdev) master->num_chipselect = SPI_N_CHIPSEL; master->setup = spi_gpio_setup; master->cleanup = spi_gpio_cleanup; +#ifdef CONFIG_OF + master->dev.of_node = pdev->dev.of_node; + + if (use_of) { + int i; + struct device_node *np = pdev->dev.of_node; + + /* + * In DT environments, take the CS GPIO from the "cs-gpios" + * property of the node. + */ + + for (i = 0; i < SPI_N_CHIPSEL; i++) + spi_gpio->cs_gpios[i] = + of_get_named_gpio(np, "cs-gpios", i); + } +#endif spi_gpio->bitbang.master = spi_master_get(master); spi_gpio->bitbang.chipselect = spi_gpio_chipselect; @@ -408,8 +512,11 @@ static int __devexit spi_gpio_remove(struct platform_device *pdev) MODULE_ALIAS("platform:" DRIVER_NAME); static struct platform_driver spi_gpio_driver = { - .driver.name = DRIVER_NAME, - .driver.owner = THIS_MODULE, + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(spi_gpio_dt_ids), + }, .probe = spi_gpio_probe, .remove = __devexit_p(spi_gpio_remove), }; 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