target/linux/brcm2708/patches-4.4/0421-spi-bcm2835-Disable-forced-software-CS.patch

   1 From e95bf039347d97f57e7045d7cd2d1f7e4daed1c6 Mon Sep 17 00:00:00 2001
   2 From: Phil Elwell <phil@raspberrypi.org>
   3 Date: Fri, 1 Jul 2016 22:09:24 +0100
   4 Subject: [PATCH 421/423] spi-bcm2835: Disable forced software CS
   5
   6 Select software CS in bcm2708_common.dtsi, and disable the automatic
   7 conversion in the driver to allow hardware CS to be re-enabled with an
   8 overlay.
   9
  10 See: https://github.com/raspberrypi/linux/issues/1547
  11
  12 Signed-off-by: Phil Elwell <phil@raspberrypi.org>
  13 ---
  14  arch/arm/boot/dts/bcm2708_common.dtsi | 2 +-
  15  drivers/spi/spi-bcm2835.c             | 2 ++
  16  2 files changed, 3 insertions(+), 1 deletion(-)
  17
  18 --- a/arch/arm/boot/dts/bcm2708_common.dtsi
  19 +++ b/arch/arm/boot/dts/bcm2708_common.dtsi
  20 @@ -183,7 +183,7 @@
  21                          * add more gpios if necessary as <&gpio 6 1>
  22                          * (but do not forget to make them output!)
  23                          */
  24 -                       cs-gpios = <0>, <0>;
  25 +                       cs-gpios = <&gpio 8 1>, <&gpio 7 1>;
  26                 };
  27
  28                 i2c0: i2c@7e205000 {
  29 --- a/drivers/spi/spi-bcm2835.c
  30 +++ b/drivers/spi/spi-bcm2835.c
  31 @@ -707,6 +707,7 @@ static int bcm2835_spi_setup(struct spi_
  32                 return -EINVAL;
  33         }
  34
  35 +#if 0
  36         /* now translate native cs to GPIO */
  37         /* first look for chip select pins in the devices pin groups */
  38         for (pingroup_index = 0;
  39 @@ -761,6 +762,7 @@ static int bcm2835_spi_setup(struct spi_
  40          * so we are setting it here explicitly
  41          */
  42         gpio_set_value(spi->cs_gpio, (spi->mode & SPI_CS_HIGH) ? 0 : 1);
  43 +#endif
  44
  45         return 0;
  46  }