From: Chris Packham Date: Tue, 23 May 2017 04:03:21 +0000 (+1200) Subject: spi: orion: Handle GPIO chip-selects X-Git-Tag: v4.13-rc1~175^2~1^2 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=b28b9149b37f909a05f1e06e5a8b262a519dbd2b;p=linux.git spi: orion: Handle GPIO chip-selects Some hardware designs use GPIOs to add (or supplement) the SPI chip-select so that more than one SPI slave device can be used. For this to work with the spi-orion driver the SPI_MASTER_GPIO_SS flag needs to be set (because the other outputs are gated internally by the CS) and the correct chip-select (in this case CS0) needs to be driven by the controller. Signed-off-by: Chris Packham Signed-off-by: Mark Brown --- diff --git a/drivers/spi/spi-orion.c b/drivers/spi/spi-orion.c index be2e87ee8b31..28fc9f161b9d 100644 --- a/drivers/spi/spi-orion.c +++ b/drivers/spi/spi-orion.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #define DRIVER_NAME "orion_spi" @@ -320,12 +321,18 @@ orion_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) static void orion_spi_set_cs(struct spi_device *spi, bool enable) { struct orion_spi *orion_spi; + int cs; + + if (gpio_is_valid(spi->cs_gpio)) + cs = 0; + else + cs = spi->chip_select; orion_spi = spi_master_get_devdata(spi->master); orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, ORION_SPI_CS_MASK); orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG, - ORION_SPI_CS(spi->chip_select)); + ORION_SPI_CS(cs)); /* Chip select logic is inverted from spi_set_cs */ if (!enable) @@ -606,6 +613,7 @@ static int orion_spi_probe(struct platform_device *pdev) master->setup = orion_spi_setup; master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16); master->auto_runtime_pm = true; + master->flags = SPI_MASTER_GPIO_SS; platform_set_drvdata(pdev, master);