diff options
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/spi-orion.c | 77 |
1 files changed, 40 insertions, 37 deletions
diff --git a/drivers/spi/spi-orion.c b/drivers/spi/spi-orion.c index d01a6adc726e..47ef6b1a2e76 100644 --- a/drivers/spi/spi-orion.c +++ b/drivers/spi/spi-orion.c @@ -20,6 +20,7 @@ #include <linux/of.h> #include <linux/of_address.h> #include <linux/of_device.h> +#include <linux/of_gpio.h> #include <linux/clk.h> #include <linux/sizes.h> #include <linux/gpio.h> @@ -681,9 +682,9 @@ static int orion_spi_probe(struct platform_device *pdev) goto out_rel_axi_clk; } - /* Scan all SPI devices of this controller for direct mapped devices */ for_each_available_child_of_node(pdev->dev.of_node, np) { u32 cs; + int cs_gpio; /* Get chip-select number from the "reg" property */ status = of_property_read_u32(np, "reg", &cs); @@ -695,6 +696,44 @@ static int orion_spi_probe(struct platform_device *pdev) } /* + * Initialize the CS GPIO: + * - properly request the actual GPIO signal + * - de-assert the logical signal so that all GPIO CS lines + * are inactive when probing for slaves + * - find an unused physical CS which will be driven for any + * slave which uses a CS GPIO + */ + cs_gpio = of_get_named_gpio(pdev->dev.of_node, "cs-gpios", cs); + if (cs_gpio > 0) { + char *gpio_name; + int cs_flags; + + if (spi->unused_hw_gpio == -1) { + dev_info(&pdev->dev, + "Selected unused HW CS#%d for any GPIO CSes\n", + cs); + spi->unused_hw_gpio = cs; + } + + gpio_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, + "%s-CS%d", dev_name(&pdev->dev), cs); + if (!gpio_name) { + status = -ENOMEM; + goto out_rel_axi_clk; + } + + cs_flags = of_property_read_bool(np, "spi-cs-high") ? + GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH; + status = devm_gpio_request_one(&pdev->dev, cs_gpio, + cs_flags, gpio_name); + if (status) { + dev_err(&pdev->dev, + "Can't request GPIO for CS %d\n", cs); + goto out_rel_axi_clk; + } + } + + /* * Check if an address is configured for this SPI device. If * not, the MBus mapping via the 'ranges' property in the 'soc' * node is not configured and this device should not use the @@ -740,44 +779,8 @@ static int orion_spi_probe(struct platform_device *pdev) if (status < 0) goto out_rel_pm; - if (master->cs_gpios) { - int i; - for (i = 0; i < master->num_chipselect; ++i) { - char *gpio_name; - - if (!gpio_is_valid(master->cs_gpios[i])) { - continue; - } - - gpio_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, - "%s-CS%d", dev_name(&pdev->dev), i); - if (!gpio_name) { - status = -ENOMEM; - goto out_rel_master; - } - - status = devm_gpio_request(&pdev->dev, - master->cs_gpios[i], gpio_name); - if (status) { - dev_err(&pdev->dev, - "Can't request GPIO for CS %d\n", - master->cs_gpios[i]); - goto out_rel_master; - } - if (spi->unused_hw_gpio == -1) { - dev_info(&pdev->dev, - "Selected unused HW CS#%d for any GPIO CSes\n", - i); - spi->unused_hw_gpio = i; - } - } - } - - return status; -out_rel_master: - spi_unregister_master(master); out_rel_pm: pm_runtime_disable(&pdev->dev); out_rel_axi_clk: |