[PATCH v5 2/2] gpio: mlxbf3: Support add_pin_ranges()

Asmaa Mnebhi
2023-08-18T16:45:09Z

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>
---
v4->v5:
- Add "Reviewed-By" Tag
v3->v4:
- Drop the common define for MLXBF3_GPIO_MAX_PINS_BLOCK0
v2->v3:
- Replace boolean logic by clear switch statement logic in
mlxbf3_gpio_add_pin_ranges()
v1->v2:
- Cleanup mlxbf3_gpio_add_pin_ranges()

drivers/gpio/gpio-mlxbf3.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)

diff --git a/drivers/gpio/gpio-mlxbf3.c b/drivers/gpio/gpio-mlxbf3.c
index e30cee108986..0a5f241a8352 100644
--- 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");
--
2.30.1