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a1383655cf
Tested on bcm2710 (Raspberry Pi 3B). Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
60 lines
1.8 KiB
Diff
60 lines
1.8 KiB
Diff
From dc1e3fefce7abd7532fbc74e26df61a8ced1dcd6 Mon Sep 17 00:00:00 2001
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From: Phil Elwell <phil@raspberrypi.org>
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Date: Tue, 15 Jan 2019 12:41:15 +0000
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Subject: [PATCH] spi: spi-bcm2835: Disable forced software CS
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With GPIO CS used by the DTBs, allow hardware CS to be selected by an
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overlay.
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Signed-off-by: Phil Elwell <phil@raspberrypi.org>
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---
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drivers/spi/spi-bcm2835.c | 37 -------------------------------------
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1 file changed, 37 deletions(-)
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--- a/drivers/spi/spi-bcm2835.c
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+++ b/drivers/spi/spi-bcm2835.c
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@@ -1279,43 +1279,6 @@ static int bcm2835_spi_setup(struct spi_
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return -EINVAL;
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}
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- /*
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- * Translate native CS to GPIO
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- *
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- * FIXME: poking around in the gpiolib internals like this is
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- * not very good practice. Find a way to locate the real problem
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- * and fix it. Why is the GPIO descriptor in spi->cs_gpiod
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- * sometimes not assigned correctly? Erroneous device trees?
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- */
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-
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- /* get the gpio chip for the base */
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- chip = gpiochip_find("pinctrl-bcm2835", chip_match_name);
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- if (!chip)
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- return 0;
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-
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- /*
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- * Retrieve the corresponding GPIO line used for CS.
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- * The inversion semantics will be handled by the GPIO core
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- * code, so we pass GPIOS_OUT_LOW for "unasserted" and
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- * the correct flag for inversion semantics. The SPI_CS_HIGH
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- * on spi->mode cannot be checked for polarity in this case
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- * as the flag use_gpio_descriptors enforces SPI_CS_HIGH.
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- */
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- if (of_property_read_bool(spi->dev.of_node, "spi-cs-high"))
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- lflags = GPIO_ACTIVE_HIGH;
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- else
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- lflags = GPIO_ACTIVE_LOW;
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- spi->cs_gpiod = gpiochip_request_own_desc(chip, 8 - spi->chip_select,
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- DRV_NAME,
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- lflags,
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- GPIOD_OUT_LOW);
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- if (IS_ERR(spi->cs_gpiod))
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- return PTR_ERR(spi->cs_gpiod);
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-
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- /* and set up the "mode" and level */
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- dev_info(&spi->dev, "setting up native-CS%i to use GPIO\n",
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- spi->chip_select);
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-
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return 0;
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}
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