diff options
Diffstat (limited to 'drivers/spi/spi-gpio.c')
| -rw-r--r-- | drivers/spi/spi-gpio.c | 45 |
1 files changed, 7 insertions, 38 deletions
diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c index 4f192e013cd6..405deb6677c1 100644 --- a/drivers/spi/spi-gpio.c +++ b/drivers/spi/spi-gpio.c @@ -39,36 +39,8 @@ struct spi_gpio { /*----------------------------------------------------------------------*/ -/* - * Because the overhead of going through four GPIO procedure calls - * per transferred bit can make performance a problem, this code - * is set up so that you can use it in either of two ways: - * - * - The slow generic way: set up platform_data to hold the GPIO - * numbers used for MISO/MOSI/SCK, and issue procedure calls for - * each of them. This driver can handle several such busses. - * - * - The quicker inlined way: only helps with platform GPIO code - * that inlines operations for constant GPIOs. This can give - * you tight (fast!) inner loops, but each such bus needs a - * new driver. You'll define a new C file, with Makefile and - * Kconfig support; the C code can be a total of six lines: - * - * #define DRIVER_NAME "myboard_spi2" - * #define SPI_MISO_GPIO 119 - * #define SPI_MOSI_GPIO 120 - * #define SPI_SCK_GPIO 121 - * #define SPI_N_CHIPSEL 4 - * #include "spi-gpio.c" - */ - -#ifndef DRIVER_NAME #define DRIVER_NAME "spi_gpio" -#define GENERIC_BITBANG /* vs tight inlines */ - -#endif - /*----------------------------------------------------------------------*/ static inline struct spi_gpio *__pure @@ -341,16 +313,14 @@ static int spi_gpio_probe_pdata(struct platform_device *pdev, struct spi_gpio *spi_gpio = spi_controller_get_devdata(host); int i; -#ifdef GENERIC_BITBANG - if (!pdata || !pdata->num_chipselect) + if (!pdata) return -ENODEV; -#endif - /* - * The host needs to think there is a chipselect even if not - * connected - */ - host->num_chipselect = pdata->num_chipselect ?: 1; + /* It's just one always-selected device, fine to continue */ + if (!pdata->num_chipselect) + return 0; + + host->num_chipselect = pdata->num_chipselect; spi_gpio->cs_gpios = devm_kcalloc(dev, host->num_chipselect, sizeof(*spi_gpio->cs_gpios), GFP_KERNEL); @@ -445,8 +415,6 @@ static int spi_gpio_probe(struct platform_device *pdev) return devm_spi_register_controller(&pdev->dev, host); } -MODULE_ALIAS("platform:" DRIVER_NAME); - static const struct of_device_id spi_gpio_dt_ids[] = { { .compatible = "spi-gpio" }, {} @@ -465,3 +433,4 @@ module_platform_driver(spi_gpio_driver); MODULE_DESCRIPTION("SPI host driver using generic bitbanged GPIO "); MODULE_AUTHOR("David Brownell"); MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRIVER_NAME); |