diff options
| author | Torsten Fleischer <torfl6749@gmail.com> | 2014-11-03 17:17:55 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2014-11-04 20:57:25 +0100 |
| commit | d1d81802522ade84128a2c66c0d500e372474dca (patch) | |
| tree | 971fe9a68d1fcc2823d5ab6cf90b0e0c6d8a9eef | |
| parent | Linux 3.18-rc1 (diff) | |
| download | linux-d1d81802522ade84128a2c66c0d500e372474dca.tar.xz linux-d1d81802522ade84128a2c66c0d500e372474dca.zip | |
spi: spi-gpio: Add dt support for a single device with no chip select
In order to describe a single slave device that has no chip select line
the 'num-chipselects' property has to be <0> and the 'cs-gpios' property
doesn't need to be set.
Signed-off-by: Torsten Fleischer <torfl6749@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
| -rw-r--r-- | Documentation/devicetree/bindings/spi/spi-gpio.txt | 6 | ||||
| -rw-r--r-- | drivers/spi/spi-gpio.c | 21 |
2 files changed, 19 insertions, 8 deletions
diff --git a/Documentation/devicetree/bindings/spi/spi-gpio.txt b/Documentation/devicetree/bindings/spi/spi-gpio.txt index 8a824be15754..a95603bcf6ff 100644 --- a/Documentation/devicetree/bindings/spi/spi-gpio.txt +++ b/Documentation/devicetree/bindings/spi/spi-gpio.txt @@ -8,8 +8,10 @@ Required properties: - gpio-sck: GPIO spec for the SCK line to use - gpio-miso: GPIO spec for the MISO line to use - gpio-mosi: GPIO spec for the MOSI line to use - - cs-gpios: GPIOs to use for chipselect lines - - num-chipselects: number of chipselect lines + - cs-gpios: GPIOs to use for chipselect lines. + Not needed if num-chipselects = <0>. + - num-chipselects: Number of chipselect lines. Should be <0> if a single device + with no chip select is connected. Example: diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c index 9f595535cf27..f0492c99d145 100644 --- a/drivers/spi/spi-gpio.c +++ b/drivers/spi/spi-gpio.c @@ -413,6 +413,7 @@ static int spi_gpio_probe(struct platform_device *pdev) struct spi_gpio_platform_data *pdata; u16 master_flags = 0; bool use_of = 0; + int num_devices; status = spi_gpio_probe_dt(pdev); if (status < 0) @@ -422,16 +423,21 @@ static int spi_gpio_probe(struct platform_device *pdev) pdata = dev_get_platdata(&pdev->dev); #ifdef GENERIC_BITBANG - if (!pdata || !pdata->num_chipselect) + if (!pdata || (!use_of && !pdata->num_chipselect)) return -ENODEV; #endif + if (use_of && !SPI_N_CHIPSEL) + num_devices = 1; + else + num_devices = SPI_N_CHIPSEL; + status = spi_gpio_request(pdata, dev_name(&pdev->dev), &master_flags); if (status < 0) return status; master = spi_alloc_master(&pdev->dev, sizeof(*spi_gpio) + - (sizeof(int) * SPI_N_CHIPSEL)); + (sizeof(int) * num_devices)); if (!master) { status = -ENOMEM; goto gpio_free; @@ -446,7 +452,7 @@ static int spi_gpio_probe(struct platform_device *pdev) master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32); master->flags = master_flags; master->bus_num = pdev->id; - master->num_chipselect = SPI_N_CHIPSEL; + master->num_chipselect = num_devices; master->setup = spi_gpio_setup; master->cleanup = spi_gpio_cleanup; #ifdef CONFIG_OF @@ -461,9 +467,12 @@ static int spi_gpio_probe(struct platform_device *pdev) * property of the node. */ - for (i = 0; i < SPI_N_CHIPSEL; i++) - spi_gpio->cs_gpios[i] = - of_get_named_gpio(np, "cs-gpios", i); + if (!SPI_N_CHIPSEL) + spi_gpio->cs_gpios[0] = SPI_GPIO_NO_CHIPSELECT; + else + for (i = 0; i < SPI_N_CHIPSEL; i++) + spi_gpio->cs_gpios[i] = + of_get_named_gpio(np, "cs-gpios", i); } #endif |