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@@ -0,0 +1,91 @@
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+From d1d81802522ade84128a2c66c0d500e372474dca Mon Sep 17 00:00:00 2001
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+From: Torsten Fleischer <[email protected]>
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+Date: Mon, 3 Nov 2014 17:17:55 +0100
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+Subject: [PATCH] spi: spi-gpio: Add dt support for a single device with no
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+ chip select
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+
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+In order to describe a single slave device that has no chip select line
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+the 'num-chipselects' property has to be <0> and the 'cs-gpios' property
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+doesn't need to be set.
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+
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+Signed-off-by: Torsten Fleischer <[email protected]>
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+Signed-off-by: Mark Brown <[email protected]>
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+---
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+ Documentation/devicetree/bindings/spi/spi-gpio.txt | 6 ++++--
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+ drivers/spi/spi-gpio.c | 21 +++++++++++++++------
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+ 2 files changed, 19 insertions(+), 8 deletions(-)
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+
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+--- a/Documentation/devicetree/bindings/spi/spi-gpio.txt
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++++ b/Documentation/devicetree/bindings/spi/spi-gpio.txt
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+@@ -8,8 +8,10 @@ Required properties:
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+ - gpio-sck: GPIO spec for the SCK line to use
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+ - gpio-miso: GPIO spec for the MISO line to use
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+ - gpio-mosi: GPIO spec for the MOSI line to use
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+- - cs-gpios: GPIOs to use for chipselect lines
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+- - num-chipselects: number of chipselect lines
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++ - cs-gpios: GPIOs to use for chipselect lines.
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++ Not needed if num-chipselects = <0>.
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++ - num-chipselects: Number of chipselect lines. Should be <0> if a single device
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++ with no chip select is connected.
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+
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+ Example:
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+
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+--- a/drivers/spi/spi-gpio.c
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++++ b/drivers/spi/spi-gpio.c
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+@@ -425,6 +425,7 @@ static int spi_gpio_probe(struct platfor
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+ struct spi_gpio_platform_data *pdata;
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+ u16 master_flags = 0;
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+ bool use_of = 0;
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++ int num_devices;
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+
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+ status = spi_gpio_probe_dt(pdev);
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+ if (status < 0)
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+@@ -434,16 +435,21 @@ static int spi_gpio_probe(struct platfor
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+
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+ pdata = dev_get_platdata(&pdev->dev);
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+ #ifdef GENERIC_BITBANG
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+- if (!pdata || !pdata->num_chipselect)
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++ if (!pdata || (!use_of && !pdata->num_chipselect))
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+ return -ENODEV;
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+ #endif
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+
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++ if (use_of && !SPI_N_CHIPSEL)
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++ num_devices = 1;
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++ else
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++ num_devices = SPI_N_CHIPSEL;
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++
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+ status = spi_gpio_request(pdata, dev_name(&pdev->dev), &master_flags);
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+ if (status < 0)
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+ return status;
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+
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+ master = spi_alloc_master(&pdev->dev, sizeof(*spi_gpio) +
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+- (sizeof(int) * SPI_N_CHIPSEL));
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++ (sizeof(int) * num_devices));
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+ if (!master) {
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+ status = -ENOMEM;
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+ goto gpio_free;
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+@@ -458,7 +464,7 @@ static int spi_gpio_probe(struct platfor
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+ master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
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+ master->flags = master_flags;
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+ master->bus_num = pdev->id;
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+- master->num_chipselect = SPI_N_CHIPSEL;
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++ master->num_chipselect = num_devices;
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+ master->setup = spi_gpio_setup;
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+ master->cleanup = spi_gpio_cleanup;
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+ #ifdef CONFIG_OF
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+@@ -473,9 +479,12 @@ static int spi_gpio_probe(struct platfor
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+ * property of the node.
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+ */
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+
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+- for (i = 0; i < SPI_N_CHIPSEL; i++)
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+- spi_gpio->cs_gpios[i] =
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+- of_get_named_gpio(np, "cs-gpios", i);
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++ if (!SPI_N_CHIPSEL)
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++ spi_gpio->cs_gpios[0] = SPI_GPIO_NO_CHIPSELECT;
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++ else
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++ for (i = 0; i < SPI_N_CHIPSEL; i++)
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++ spi_gpio->cs_gpios[i] =
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++ of_get_named_gpio(np, "cs-gpios", i);
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+ }
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+ #endif
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+
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Jonas Gorski