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authorLinus Torvalds <torvalds@linux-foundation.org>2015-04-18 08:22:10 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2015-04-18 08:22:10 -0400
commit510965dd4a0a59504ba38455f77339ea8b4c6a70 (patch)
tree36492629ac68de94457482562660154f28e9e039 /drivers/gpio/gpiolib-of.c
parent40d7839879b4584f91522d841afb22ed401cf40f (diff)
parent03daa6f82f2b634019fe8261698f6af3c133497f (diff)
downloadlinux-510965dd4a0a59504ba38455f77339ea8b4c6a70.tar.bz2
Merge tag 'gpio-v4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO updates from Linus Walleij: "This is the bulk of GPIO changes for the v4.1 development cycle: - A new GPIO hogging mechanism has been added. This can be used on boards that want to drive some GPIO line high, low, or set it as input on boot and then never touch it again. For some embedded systems this is bliss and simplifies things to a great extent. - Some API cleanup and closure: gpiod_get_array() and gpiod_put_array() has been added to get and put GPIOs in bulk as was possible with the non-descriptor API. - Encapsulate cross-calls to the pin control subsystem in <linux/gpio/driver.h>. Now this should be the only header any GPIO driver needs to include or something is wrong. Cleanups restricting drivers to this include are welcomed if tested. - Sort the GPIO Kconfig and split it into submenus, as it was becoming and unstructured, illogical and unnavigatable mess. I hope this is easier to follow. Menus that require a certain subsystem like I2C can now be hidden nicely for example, still working on others. - New drivers: - New driver for the Altera Soft GPIO. - The F7188x driver now handles the F71869 and F71869A variants. - The MIPS Loongson driver has been moved to drivers/gpio for consolidation and cleanup. - Cleanups: - The MAX732x is converted to use the GPIOLIB_IRQCHIP infrastructure. - The PCF857x is converted to use the GPIOLIB_IRQCHIP infrastructure. - Radical cleanup of the OMAP driver. - Misc: - Enable the DWAPB GPIO for all architectures. This is a "hard IP" block from Synopsys which has started to turn up in so diverse architectures as X86 Quark, ARC and a slew of ARM systems. So even though it's not an expander, it's generic enough to be available for all. - We add a mock GPIO on Crystalcove PMIC after a long discussion with Daniel Vetter et al, tracing back to the shootout at the kernel summit where DRM drivers and sub-componentization was discussed. In this case a mock GPIO is assumed to be the best compromise gaining some reuse of infrastructure without making DRM drivers overly complex at the same time. Let's see" * tag 'gpio-v4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (62 commits) Revert "gpio: sch: use uapi/linux/pci_ids.h directly" gpio: dwapb: remove dependencies gpio: dwapb: enable for ARC gpio: removing kfree remove functionality gpio: mvebu: Fix mask/unmask managment per irq chip type gpio: split GPIO drivers in submenus gpio: move MFD GPIO drivers under their own comment gpio: move BCM Kona Kconfig option gpio: arrange SPI Kconfig symbols alphabetically gpio: arrange PCI GPIO controllers alphabetically gpio: arrange I2C Kconfig symbols alphabetically gpio: arrange Kconfig symbols alphabetically gpio: ich: Implement get_direction function gpio: use (!foo) instead of (foo == NULL) gpio: arizona: drop owner assignment from platform_drivers gpio: max7300: remove 'ret' variable gpio: use devm_kzalloc gpio: sch: use uapi/linux/pci_ids.h directly gpio: x-gene: fix devm_ioremap_resource() check gpio: loongson: Add Loongson-3A/3B GPIO driver support ...
Diffstat (limited to 'drivers/gpio/gpiolib-of.c')
-rw-r--r--drivers/gpio/gpiolib-of.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index 4650bf830d6b..a6c67c6b4680 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -22,6 +22,7 @@
#include <linux/of_gpio.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/slab.h>
+#include <linux/gpio/machine.h>
#include "gpiolib.h"
@@ -118,6 +119,114 @@ int of_get_named_gpio_flags(struct device_node *np, const char *list_name,
EXPORT_SYMBOL(of_get_named_gpio_flags);
/**
+ * of_get_gpio_hog() - Get a GPIO hog descriptor, names and flags for GPIO API
+ * @np: device node to get GPIO from
+ * @name: GPIO line name
+ * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
+ * of_get_gpio_hog()
+ * @dflags: gpiod_flags - optional GPIO initialization flags
+ *
+ * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
+ * value on the error condition.
+ */
+static struct gpio_desc *of_get_gpio_hog(struct device_node *np,
+ const char **name,
+ enum gpio_lookup_flags *lflags,
+ enum gpiod_flags *dflags)
+{
+ struct device_node *chip_np;
+ enum of_gpio_flags xlate_flags;
+ struct gpio_desc *desc;
+ struct gg_data gg_data = {
+ .flags = &xlate_flags,
+ };
+ u32 tmp;
+ int i, ret;
+
+ chip_np = np->parent;
+ if (!chip_np)
+ return ERR_PTR(-EINVAL);
+
+ xlate_flags = 0;
+ *lflags = 0;
+ *dflags = 0;
+
+ ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);
+ if (ret)
+ return ERR_PTR(ret);
+
+ if (tmp > MAX_PHANDLE_ARGS)
+ return ERR_PTR(-EINVAL);
+
+ gg_data.gpiospec.args_count = tmp;
+ gg_data.gpiospec.np = chip_np;
+ for (i = 0; i < tmp; i++) {
+ ret = of_property_read_u32_index(np, "gpios", i,
+ &gg_data.gpiospec.args[i]);
+ if (ret)
+ return ERR_PTR(ret);
+ }
+
+ gpiochip_find(&gg_data, of_gpiochip_find_and_xlate);
+ if (!gg_data.out_gpio) {
+ if (np->parent == np)
+ return ERR_PTR(-ENXIO);
+ else
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (xlate_flags & OF_GPIO_ACTIVE_LOW)
+ *lflags |= GPIO_ACTIVE_LOW;
+
+ if (of_property_read_bool(np, "input"))
+ *dflags |= GPIOD_IN;
+ else if (of_property_read_bool(np, "output-low"))
+ *dflags |= GPIOD_OUT_LOW;
+ else if (of_property_read_bool(np, "output-high"))
+ *dflags |= GPIOD_OUT_HIGH;
+ else {
+ pr_warn("GPIO line %d (%s): no hogging state specified, bailing out\n",
+ desc_to_gpio(gg_data.out_gpio), np->name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (name && of_property_read_string(np, "line-name", name))
+ *name = np->name;
+
+ desc = gg_data.out_gpio;
+
+ return desc;
+}
+
+/**
+ * of_gpiochip_scan_hogs - Scan gpio-controller and apply GPIO hog as requested
+ * @chip: gpio chip to act on
+ *
+ * This is only used by of_gpiochip_add to request/set GPIO initial
+ * configuration.
+ */
+static void of_gpiochip_scan_hogs(struct gpio_chip *chip)
+{
+ struct gpio_desc *desc = NULL;
+ struct device_node *np;
+ const char *name;
+ enum gpio_lookup_flags lflags;
+ enum gpiod_flags dflags;
+
+ for_each_child_of_node(chip->of_node, np) {
+ if (!of_property_read_bool(np, "gpio-hog"))
+ continue;
+
+ desc = of_get_gpio_hog(np, &name, &lflags, &dflags);
+ if (IS_ERR(desc))
+ continue;
+
+ if (gpiod_hog(desc, name, lflags, dflags))
+ continue;
+ }
+}
+
+/**
* of_gpio_simple_xlate - translate gpio_spec to the GPIO number and flags
* @gc: pointer to the gpio_chip structure
* @np: device node of the GPIO chip
@@ -326,6 +435,8 @@ void of_gpiochip_add(struct gpio_chip *chip)
of_gpiochip_add_pin_range(chip);
of_node_get(chip->of_node);
+
+ of_gpiochip_scan_hogs(chip);
}
void of_gpiochip_remove(struct gpio_chip *chip)