#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>
struct spi_bitbang bitbang;
struct spi_gpio_platform_data pdata;
struct platform_device *pdev;
+ int cs_gpios[0];
};
/*----------------------------------------------------------------------*/
/*----------------------------------------------------------------------*/
-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 */
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)
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));
!(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);
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);
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;
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
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;
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;
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),
};
projects / ~andy / linux / blobdiff