bcm27xx: import latest patches from the RPi foundation

bcm2708: boot tested on RPi B+ v1.2
bcm2709: boot tested on RPi 3B v1.2 and RPi 4B v1.1 4G
bcm2710: boot tested on RPi 3B v1.2
bcm2711: boot tested on RPi 4B v1.1 4G

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
(cherry-picked from commit f07e572f64)

1 files changed, 48 insertions, 0 deletions

diff --git a/target/linux/bcm27xx/patches-5.4/950-0646-spi-Force-CS_HIGH-if-GPIO-descriptors-are-used.patch b/target/linux/bcm27xx/patches-5.4/950-0646-spi-Force-CS_HIGH-if-GPIO-descriptors-are-used.patch
new file mode 100644
index 0000000000..42d22c3003
--- /dev/null
+++ b/target/linux/bcm27xx/patches-5.4/950-0646-spi-Force-CS_HIGH-if-GPIO-descriptors-are-used.patch
@@ -0,0 +1,48 @@
+From 5f2eface651ba5da9caaa84ccca14b9202ba6202 Mon Sep 17 00:00:00 2001
+From: Phil Elwell <phil@raspberrypi.com>
+Date: Fri, 17 Apr 2020 10:46:19 +0100
+Subject: [PATCH] spi: Force CS_HIGH if GPIO descriptors are used
+
+Commit f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs")
+amended of_spi_parse_dt() to always set SPI_CS_HIGH for SPI slaves whose
+Chip Select is defined by a "cs-gpios" devicetree property.
+
+This change breaks drivers whose probe functions set the mode field of
+the spi_device because in doing so they clear the SPI_CS_HIGH flag.
+
+Fix by setting SPI_CS_HIGH in spi_setup (under the same conditions as
+in of_spi_parse_dt()).
+
+See also: 83b2a8fe43bd ("spi: spidev: Fix CS polarity if GPIO descriptors are used")
+
+Fixes: f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs")
+Signed-off-by: Phil Elwell <phil@raspberrypi.com>
+---
+ drivers/spi/spi.c | 9 +++++++++
+ 1 file changed, 9 insertions(+)
+
+--- a/drivers/spi/spi.c
++++ b/drivers/spi/spi.c
+@@ -3115,6 +3115,7 @@ static int __spi_validate_bits_per_word(
+  */
+ int spi_setup(struct spi_device *spi)
+ {
++	struct spi_controller *ctlr = spi->controller;
+ 	unsigned	bad_bits, ugly_bits;
+ 	int		status;
+ 
+@@ -3132,6 +3133,14 @@ int spi_setup(struct spi_device *spi)
+ 		(SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL |
+ 		 SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL)))
+ 		return -EINVAL;
++
++	if (ctlr->use_gpio_descriptors && ctlr->cs_gpiods &&
++	    ctlr->cs_gpiods[spi->chip_select] && !(spi->mode & SPI_CS_HIGH)) {
++		dev_warn(&spi->dev,
++			 "setup: forcing CS_HIGH (use_gpio_descriptors)\n");
++		spi->mode |= SPI_CS_HIGH;
++	}
++
+ 	/* help drivers fail *cleanly* when they need options
+ 	 * that aren't supported with their current controller
+ 	 * SPI_CS_WORD has a fallback software implementation,