Many applications require more chip select lines than the board or processor allow. Introduce a mechanism to allow use of GPIO pins as chip select lines with the McSPI controller. To use this functionality, one simply provides a table mapping CS line numbers to GPIO numbers in omap2_mcspi_platform_config.cs_gpios.
Signed-off-by: Ben Gamari <bgamari.f...@gmail.com> --- arch/arm/plat-omap/include/plat/mcspi.h | 3 ++- drivers/spi/omap2_mcspi.c | 15 ++++++++++----- 2 files changed, 12 insertions(+), 6 deletions(-) diff --git a/arch/arm/plat-omap/include/plat/mcspi.h b/arch/arm/plat-omap/include/plat/mcspi.h index 1254e49..cac1d84 100644 --- a/arch/arm/plat-omap/include/plat/mcspi.h +++ b/arch/arm/plat-omap/include/plat/mcspi.h @@ -2,7 +2,8 @@ #define _OMAP2_MCSPI_H struct omap2_mcspi_platform_config { - unsigned short num_cs; + unsigned short num_cs; + int *cs_gpios; }; struct omap2_mcspi_device_config { diff --git a/drivers/spi/omap2_mcspi.c b/drivers/spi/omap2_mcspi.c index abb1ffb..59cbed4 100644 --- a/drivers/spi/omap2_mcspi.c +++ b/drivers/spi/omap2_mcspi.c @@ -35,6 +35,7 @@ #include <linux/slab.h> #include <linux/spi/spi.h> +#include <linux/gpio.h> #include <plat/dma.h> #include <plat/clock.h> @@ -235,11 +236,15 @@ static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable) static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active) { - u32 l; - - l = mcspi_cached_chconf0(spi); - MOD_REG_BIT(l, OMAP2_MCSPI_CHCONF_FORCE, cs_active); - mcspi_write_chconf0(spi, l); + struct omap2_mcspi_platform_config *pconfig = spi->master->dev.platform_data; + if (pconfig->cs_gpios) { + int gpio = pconfig->cs_gpios[spi->chip_select]; + gpio_set_value(gpio, cs_active); + } else { + u32 l = mcspi_cached_chconf0(spi); + MOD_REG_BIT(l, OMAP2_MCSPI_CHCONF_FORCE, cs_active); + mcspi_write_chconf0(spi, l); + } } static void omap2_mcspi_set_master_mode(struct spi_master *master) -- 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html