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authorFelix Fietkau <nbd@nbd.name>2016-12-09 20:48:52 +0100
committerMark Brown <broonie@kernel.org>2016-12-14 17:36:57 +0000
commit22c76326bff810d220fffdbaab949d09e2564067 (patch)
tree6fd0c7de6e3ece87325411ae3afe72d104d326ca /drivers/spi
parentfafd67940774733fa97f4b09412aea6981b82e0a (diff)
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spi: spi-ath79: support multiple internal chip select lines
Several devices with multiple flash chips use the internal chip select lines. Don't assume that chip select 1 and above are GPIO lines. Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r--drivers/spi/spi-ath79.c21
1 files changed, 11 insertions, 10 deletions
diff --git a/drivers/spi/spi-ath79.c b/drivers/spi/spi-ath79.c
index f369174fbd88..3e9b928b563b 100644
--- a/drivers/spi/spi-ath79.c
+++ b/drivers/spi/spi-ath79.c
@@ -78,14 +78,16 @@ static void ath79_spi_chipselect(struct spi_device *spi, int is_active)
ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, sp->ioc_base);
}
- if (spi->chip_select) {
+ if (gpio_is_valid(spi->cs_gpio)) {
/* SPI is normally active-low */
gpio_set_value(spi->cs_gpio, cs_high);
} else {
+ u32 cs_bit = AR71XX_SPI_IOC_CS(spi->chip_select);
+
if (cs_high)
- sp->ioc_base |= AR71XX_SPI_IOC_CS0;
+ sp->ioc_base |= cs_bit;
else
- sp->ioc_base &= ~AR71XX_SPI_IOC_CS0;
+ sp->ioc_base &= ~cs_bit;
ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, sp->ioc_base);
}
@@ -118,11 +120,8 @@ static int ath79_spi_setup_cs(struct spi_device *spi)
struct ath79_spi *sp = ath79_spidev_to_sp(spi);
int status;
- if (spi->chip_select && !gpio_is_valid(spi->cs_gpio))
- return -EINVAL;
-
status = 0;
- if (spi->chip_select) {
+ if (gpio_is_valid(spi->cs_gpio)) {
unsigned long flags;
flags = GPIOF_DIR_OUT;
@@ -134,10 +133,12 @@ static int ath79_spi_setup_cs(struct spi_device *spi)
status = gpio_request_one(spi->cs_gpio, flags,
dev_name(&spi->dev));
} else {
+ u32 cs_bit = AR71XX_SPI_IOC_CS(spi->chip_select);
+
if (spi->mode & SPI_CS_HIGH)
- sp->ioc_base &= ~AR71XX_SPI_IOC_CS0;
+ sp->ioc_base &= ~cs_bit;
else
- sp->ioc_base |= AR71XX_SPI_IOC_CS0;
+ sp->ioc_base |= cs_bit;
ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, sp->ioc_base);
}
@@ -147,7 +148,7 @@ static int ath79_spi_setup_cs(struct spi_device *spi)
static void ath79_spi_cleanup_cs(struct spi_device *spi)
{
- if (spi->chip_select) {
+ if (gpio_is_valid(spi->cs_gpio)) {
gpio_free(spi->cs_gpio);
}
}