diff options
| -rw-r--r-- | drivers/spi/spi-cadence.c | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/drivers/spi/spi-cadence.c b/drivers/spi/spi-cadence.c index 1c57ce64abba..f0b5c7b91f37 100644 --- a/drivers/spi/spi-cadence.c +++ b/drivers/spi/spi-cadence.c @@ -13,6 +13,7 @@ #include <linux/clk.h> #include <linux/delay.h> +#include <linux/gpio.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/module.h> @@ -127,6 +128,10 @@ struct cdns_spi { u32 is_decoded_cs; }; +struct cdns_spi_device_data { + bool gpio_requested; +}; + /* Macros for the SPI controller read/write */ static inline u32 cdns_spi_read(struct cdns_spi *xspi, u32 offset) { @@ -456,6 +461,64 @@ static int cdns_unprepare_transfer_hardware(struct spi_master *master) return 0; } +static int cdns_spi_setup(struct spi_device *spi) +{ + + int ret = -EINVAL; + struct cdns_spi_device_data *cdns_spi_data = spi_get_ctldata(spi); + + /* this is a pin managed by the controller, leave it alone */ + if (spi->cs_gpio == -ENOENT) + return 0; + + /* this seems to be the first time we're here */ + if (!cdns_spi_data) { + cdns_spi_data = kzalloc(sizeof(*cdns_spi_data), GFP_KERNEL); + if (!cdns_spi_data) + return -ENOMEM; + cdns_spi_data->gpio_requested = false; + spi_set_ctldata(spi, cdns_spi_data); + } + + /* if we haven't done so, grab the gpio */ + if (!cdns_spi_data->gpio_requested && gpio_is_valid(spi->cs_gpio)) { + ret = gpio_request_one(spi->cs_gpio, + (spi->mode & SPI_CS_HIGH) ? + GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH, + dev_name(&spi->dev)); + if (ret) + dev_err(&spi->dev, "can't request chipselect gpio %d\n", + spi->cs_gpio); + else + cdns_spi_data->gpio_requested = true; + } else { + if (gpio_is_valid(spi->cs_gpio)) { + int mode = ((spi->mode & SPI_CS_HIGH) ? + GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH); + + ret = gpio_direction_output(spi->cs_gpio, mode); + if (ret) + dev_err(&spi->dev, "chipselect gpio %d setup failed (%d)\n", + spi->cs_gpio, ret); + } + } + + return ret; +} + +static void cdns_spi_cleanup(struct spi_device *spi) +{ + struct cdns_spi_device_data *cdns_spi_data = spi_get_ctldata(spi); + + if (cdns_spi_data) { + if (cdns_spi_data->gpio_requested) + gpio_free(spi->cs_gpio); + kfree(cdns_spi_data); + spi_set_ctldata(spi, NULL); + } + +} + /** * cdns_spi_probe - Probe method for the SPI driver * @pdev: Pointer to the platform_device structure @@ -555,6 +618,8 @@ static int cdns_spi_probe(struct platform_device *pdev) master->transfer_one = cdns_transfer_one; master->unprepare_transfer_hardware = cdns_unprepare_transfer_hardware; master->set_cs = cdns_spi_chipselect; + master->setup = cdns_spi_setup; + master->cleanup = cdns_spi_cleanup; master->auto_runtime_pm = true; master->mode_bits = SPI_CPOL | SPI_CPHA; |