From 9c86f12a36479dec06df3e4a4f31cecf8eba0222 Mon Sep 17 00:00:00 2001 From: Gregory CLEMENT Date: Thu, 17 Oct 2019 16:18:46 +0200 Subject: [PATCH] spi: atmel: Improve CS0 case support on AT91RM9200 Thanks to the recent change in this driver, it is now possible to prevent using the CS0 with GPIO during setup. It then allows to remove the special handling of this case in the cs_activate() and cs_deactivate() functions. Signed-off-by: Gregory CLEMENT Link: https://lore.kernel.org/r/20191017141846.7523-8-gregory.clement@bootlin.com Signed-off-by: Mark Brown --- drivers/spi/spi-atmel.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index ac5e2dd..d88e2aa 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -371,7 +371,7 @@ static void cs_activate(struct atmel_spi *as, struct spi_device *spi) mr = spi_readl(as, MR); mr = SPI_BFINS(PCS, ~(1 << chip_select), mr); - if (spi->cs_gpiod && spi->chip_select != 0) + if (spi->cs_gpiod) gpiod_set_value(spi->cs_gpiod, 1); spi_writel(as, MR, mr); } @@ -402,7 +402,7 @@ static void cs_deactivate(struct atmel_spi *as, struct spi_device *spi) if (!spi->cs_gpiod) spi_writel(as, CR, SPI_BIT(LASTXFER)); - else if (atmel_spi_is_v2(as) || spi->chip_select != 0) + else gpiod_set_value(spi->cs_gpiod, 0); } @@ -1193,7 +1193,16 @@ static void initialize_native_cs_for_gpio(struct atmel_spi *as) if (!master->cs_gpiods) return; /* No CS GPIO */ - for (i = 0; i < 4; i++) + /* + * On the first version of the controller (AT91RM9200), CS0 + * can't be used associated with GPIO + */ + if (atmel_spi_is_v2(as)) + i = 0; + else + i = 1; + + for (; i < 4; i++) if (master->cs_gpiods[i]) as->native_cs_free |= BIT(i); -- 2.7.4