This will allow to export gpios with or without names

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <[email protected]>
---
 Documentation/devicetree/bindings/gpio/gpio.txt |   60 ++++++++++++++++++++++
 drivers/gpio/gpiolib-of.c                       |   61 +++++++++++++++++++++++
 2 files changed, 121 insertions(+)

diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt 
b/Documentation/devicetree/bindings/gpio/gpio.txt
index a336287..c2a9024 100644
--- a/Documentation/devicetree/bindings/gpio/gpio.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio.txt
@@ -112,3 +112,63 @@ where,
 
 The pinctrl node must have "#gpio-range-cells" property to show number of
 arguments to pass with phandle from gpio controllers node.
+
+3) gpio-export
+--------------
+
+gpio-export will allow you to automatically export gpio
+
+required properties:
+- compatible: Should be "gpio-export"
+
+in each child node will reprensent a gpio or if no name is specified
+a list of gpio to export
+
+required properties:
+- gpios: gpio to export
+
+optional properties:
+ - gpio-export,name: export name
+ - gpio-export,output: to set the as output with default value
+                      if no present gpio as input
+ - pio-export,direction_may_change: boolean to allow the direction to be 
controllable
+
+Example:
+
+
+gpio_export {
+       compatible = "gpio-export";
+       #size-cells = <0>;
+
+       in {
+               gpio-export,name = "in";
+               gpios = <&pioC 20 0>;
+       };
+
+       out {
+               gpio-export,name = "out";
+               gpio-export,output = <1>;
+               gpio-export,direction_may_change;
+               gpios = <&pioC 21 0>;
+       };
+
+       in_out {
+               gpio-export,name = "in_out";
+               gpio-export,direction_may_change;
+               gpios = <&pioC 21 0>;
+       };
+
+       gpios_in {
+               gpios = <&pioB 0 0
+                        &pioB 3 0
+                        &pioC 4 0>;
+               gpio-export,direction_may_change;
+       };
+
+       gpios_out {
+               gpios = <&pioB 1 0
+                        &pioB 2 0
+                        &pioC 3 0>;
+               gpio-export,output = <1>;
+       };
+};
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index a40cd84..0ab9be4 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -21,6 +21,8 @@
 #include <linux/of_gpio.h>
 #include <linux/pinctrl/pinctrl.h>
 #include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
 
 /* Private data structure for of_gpiochip_find_and_xlate */
 struct gg_data {
@@ -277,3 +279,62 @@ void of_gpiochip_remove(struct gpio_chip *chip)
        if (chip->of_node)
                of_node_put(chip->of_node);
 }
+
+static struct of_device_id gpio_export_ids[] = {
+       { .compatible = "gpio-export" },
+       { /* sentinel */ }
+};
+
+static int __init of_gpio_export_probe(struct platform_device *pdev)
+{
+       struct device_node *np = pdev->dev.of_node;
+       struct device_node *cnp;
+       u32 val;
+       int nb = 0;
+
+       for_each_child_of_node(np, cnp) {
+               const char *name = NULL;
+               int gpio;
+               bool dmc;
+               int max_gpio = 1;
+               int i;
+
+               of_property_read_string(cnp, "gpio-export,name", &name);
+
+               if (!name)
+                       max_gpio = of_gpio_count(cnp);
+
+               for (i = 0; i < max_gpio; i++) {
+                       gpio = of_get_gpio(cnp, i);
+                       if (devm_gpio_request(&pdev->dev, gpio, name ? name : 
of_node_full_name(np)))
+                               continue;
+
+                       if (!of_property_read_u32(cnp, "gpio-export,output", 
&val))
+                               gpio_direction_output(gpio, val);
+                       else
+                               gpio_direction_input(gpio);
+
+                       dmc = of_property_read_bool(np, 
"gpio-export,direction_may_change");
+                       gpio_export_with_name(gpio, dmc, name);
+                       nb++;
+               }
+       }
+
+       dev_info(&pdev->dev, "%d gpio(s) exported\n", nb);
+
+       return 0;
+}
+
+static struct platform_driver gpio_export_driver = {
+       .driver         = {
+               .name           = "gpio-export",
+               .owner  = THIS_MODULE,
+               .of_match_table = of_match_ptr(gpio_export_ids),
+       },
+};
+
+static int __init of_gpio_export_init(void)
+{
+       return platform_driver_probe(&gpio_export_driver, of_gpio_export_probe);
+}
+device_initcall(of_gpio_export_init);
-- 
1.7.10.4

_______________________________________________
devicetree-discuss mailing list
[email protected]
https://lists.ozlabs.org/listinfo/devicetree-discuss

Reply via email to