gpio: mlxbf3: Support add_pin_ranges()

Support add_pin_ranges() so that pinctrl_gpio_request() can be called.
The GPIO value is not modified when the user runs the "gpioset" tool.
This is because when gpiochip_generic_request is invoked by the gpio-mlxbf3
driver, "pin_ranges" is empty so it skips "pinctrl_gpio_request()".
pinctrl_gpio_request() is essential in the code flow because it changes the
mux value so that software has control over modifying the GPIO value.
Adding add_pin_ranges() creates a dependency on the pinctrl-mlxbf3.c driver.

Fixes: cd33f216d24 ("gpio: mlxbf3: Add gpio driver support")
Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

diff --git a/drivers/gpio/gpio-mlxbf3.c b/drivers/gpio/gpio-mlxbf3.c
index e30cee1..0a5f241 100644 (file)
--- a/drivers/gpio/gpio-mlxbf3.c
+++ b/drivers/gpio/gpio-mlxbf3.c
@@ -19,6 +19,8 @@
  * gpio[1]: HOST_GPIO32->HOST_GPIO55
  */
 #define MLXBF3_GPIO_MAX_PINS_PER_BLOCK 32
+#define MLXBF3_GPIO_MAX_PINS_BLOCK0    32
+#define MLXBF3_GPIO_MAX_PINS_BLOCK1    24
 
 /*
  * fw_gpio[x] block registers and their offset
@@ -158,6 +160,26 @@ static const struct irq_chip gpio_mlxbf3_irqchip = {
        GPIOCHIP_IRQ_RESOURCE_HELPERS,
 };
 
+static int mlxbf3_gpio_add_pin_ranges(struct gpio_chip *chip)
+{
+       unsigned int id;
+
+       switch(chip->ngpio) {
+       case MLXBF3_GPIO_MAX_PINS_BLOCK0:
+               id = 0;
+               break;
+       case MLXBF3_GPIO_MAX_PINS_BLOCK1:
+               id = 1;
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       return gpiochip_add_pin_range(chip, "MLNXBF34:00",
+                       chip->base, id * MLXBF3_GPIO_MAX_PINS_PER_BLOCK,
+                       chip->ngpio);
+}
+
 static int mlxbf3_gpio_probe(struct platform_device *pdev)
 {
        struct device *dev = &pdev->dev;
@@ -197,6 +219,7 @@ static int mlxbf3_gpio_probe(struct platform_device *pdev)
        gc->request = gpiochip_generic_request;
        gc->free = gpiochip_generic_free;
        gc->owner = THIS_MODULE;
+       gc->add_pin_ranges = mlxbf3_gpio_add_pin_ranges;
 
        irq = platform_get_irq(pdev, 0);
        if (irq >= 0) {
@@ -243,6 +266,7 @@ static struct platform_driver mlxbf3_gpio_driver = {
 };
 module_platform_driver(mlxbf3_gpio_driver);
 
+MODULE_SOFTDEP("pre: pinctrl-mlxbf3");
 MODULE_DESCRIPTION("NVIDIA BlueField-3 GPIO Driver");
 MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>");
 MODULE_LICENSE("Dual BSD/GPL");