openwrt/target/linux/bcm27xx/patches-5.4/950-0135-spi-spi-bcm2835-Disable-forced-software-CS.patch

From dc1e3fefce7abd7532fbc74e26df61a8ced1dcd6 Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.org>
Date: Tue, 15 Jan 2019 12:41:15 +0000
Subject: [PATCH] spi: spi-bcm2835: Disable forced software CS

With GPIO CS used by the DTBs, allow hardware CS to be selected by an
overlay.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
 drivers/spi/spi-bcm2835.c | 37 -------------------------------------
 1 file changed, 37 deletions(-)

--- a/drivers/spi/spi-bcm2835.c
+++ b/drivers/spi/spi-bcm2835.c
@@ -1279,43 +1279,6 @@ static int bcm2835_spi_setup(struct spi_
 		return -EINVAL;
 	}
 
-	/*
-	 * Translate native CS to GPIO
-	 *
-	 * FIXME: poking around in the gpiolib internals like this is
-	 * not very good practice. Find a way to locate the real problem
-	 * and fix it. Why is the GPIO descriptor in spi->cs_gpiod
-	 * sometimes not assigned correctly? Erroneous device trees?
-	 */
-
-	/* get the gpio chip for the base */
-	chip = gpiochip_find("pinctrl-bcm2835", chip_match_name);
-	if (!chip)
-		return 0;
-
-	/*
-	 * Retrieve the corresponding GPIO line used for CS.
-	 * The inversion semantics will be handled by the GPIO core
-	 * code, so we pass GPIOS_OUT_LOW for "unasserted" and
-	 * the correct flag for inversion semantics. The SPI_CS_HIGH
-	 * on spi->mode cannot be checked for polarity in this case
-	 * as the flag use_gpio_descriptors enforces SPI_CS_HIGH.
-	 */
-	if (of_property_read_bool(spi->dev.of_node, "spi-cs-high"))
-		lflags = GPIO_ACTIVE_HIGH;
-	else
-		lflags = GPIO_ACTIVE_LOW;
-	spi->cs_gpiod = gpiochip_request_own_desc(chip, 8 - spi->chip_select,
-						  DRV_NAME,
-						  lflags,
-						  GPIOD_OUT_LOW);
-	if (IS_ERR(spi->cs_gpiod))
-		return PTR_ERR(spi->cs_gpiod);
-
-	/* and set up the "mode" and level */
-	dev_info(&spi->dev, "setting up native-CS%i to use GPIO\n",
-		 spi->chip_select);
-
 	return 0;
 }