brcm2708: update to latest patches from RPi Foundation

[openwrt/openwrt.git] / target / linux / brcm2708 / patches-4.19 / 950-0144-spi-Make-GPIO-CSs-honour-the-SPI_NO_CS-flag.patch

diff --git a/target/linux/brcm2708/patches-4.19/950-0144-spi-Make-GPIO-CSs-honour-the-SPI_NO_CS-flag.patch b/target/linux/brcm2708/patches-4.19/950-0144-spi-Make-GPIO-CSs-honour-the-SPI_NO_CS-flag.patch
new file mode 100644 (file)
index 0000000..7276240
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.19/950-0144-spi-Make-GPIO-CSs-honour-the-SPI_NO_CS-flag.patch
@@ -0,0 +1,32 @@
+From d7aa9d52b7f9b2d600f9b2479767c24d438a2c68 Mon Sep 17 00:00:00 2001
+From: Phil Elwell <phil@raspberrypi.org>
+Date: Tue, 3 Jul 2018 14:23:47 +0100
+Subject: [PATCH] spi: Make GPIO CSs honour the SPI_NO_CS flag
+
+The SPI configuration state includes an SPI_NO_CS flag that disables
+all CS line manipulation, for applications that want to manage their
+own chip selects. However, this flag is ignored by the GPIO CS code
+in the SPI framework.
+
+Correct this omission with a trivial patch.
+
+See: https://github.com/raspberrypi/linux/issues/2169
+
+Signed-off-by: Phil Elwell <phil@raspberrypi.org>
+---
+ drivers/spi/spi.c | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+--- a/drivers/spi/spi.c
++++ b/drivers/spi/spi.c
+@@ -733,7 +733,9 @@ static void spi_set_cs(struct spi_device
+               enable = !enable;
+ 
+       if (gpio_is_valid(spi->cs_gpio)) {
+-              gpio_set_value_cansleep(spi->cs_gpio, !enable);
++              /* Honour the SPI_NO_CS flag */
++              if (!(spi->mode & SPI_NO_CS))
++                      gpio_set_value_cansleep(spi->cs_gpio, !enable);
+               /* Some SPI masters need both GPIO CS & slave_select */
+               if ((spi->controller->flags & SPI_MASTER_GPIO_SS) &&
+                   spi->controller->set_cs)