[PATCH v3 04/10] gpio: aggregator: refactor the code to add GPIO desc in the forwarder

Thomas Richard
2025-04-16T14:08:18Z

Create a dedicated function to add a GPIO desc in the forwarder. Instead of
passing an array of GPIO desc, now the GPIO desc are passed on by one to
the forwarder.

Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
drivers/gpio/gpio-aggregator.c | 57 +++++++++++++++++++++++++++++-------------
1 file changed, 40 insertions(+), 17 deletions(-)

diff --git a/drivers/gpio/gpio-aggregator.c b/drivers/gpio/gpio-aggregator.c
index a5e3ae4d8813..4d6e41e02659 100644
--- a/drivers/gpio/gpio-aggregator.c
+++ b/drivers/gpio/gpio-aggregator.c
@@ -510,6 +510,10 @@ devm_gpiochip_fwd_alloc(struct device *dev, unsigned int ngpios)
if (!fwd)
return ERR_PTR(-ENOMEM);

+ fwd->descs = devm_kcalloc(dev, ngpios, sizeof(*fwd->descs), GFP_KERNEL);
+ if (!fwd->descs)
+ return ERR_PTR(-ENOMEM);
+
chip = &fwd->chip;

chip->label = label;
@@ -529,6 +533,39 @@ devm_gpiochip_fwd_alloc(struct device *dev, unsigned int ngpios)
return fwd;
}

+static int gpiochip_fwd_add_gpio_desc(struct gpiochip_fwd *fwd,
+ struct gpio_desc *desc,
+ unsigned int offset)
+{
+ struct gpio_chip *parent = gpiod_to_chip(desc);
+ struct gpio_chip *chip = &fwd->chip;
+
+ if (offset > chip->ngpio)
+ return -EINVAL;
+
+ if (fwd->descs[offset])
+ return -EEXIST;
+
+ /*
+ * If any of the GPIO lines are sleeping, then the entire forwarder
+ * will be sleeping.
+ * If any of the chips support .set_config(), then the forwarder will
+ * support setting configs.
+ */
+ if (gpiod_cansleep(desc))
+ chip->can_sleep = true;
+
+ if (parent && parent->set_config)
+ chip->set_config = gpio_fwd_set_config;
+
+ fwd->descs[offset] = desc;
+
+ dev_dbg(chip->parent, "%u => gpio %d irq %d\n", offset,
+ desc_to_gpio(desc), gpiod_to_irq(desc));
+
+ return 0;
+}
+
/**
* gpiochip_fwd_create() - Create a new GPIO forwarder
* @dev: Parent device pointer
@@ -560,26 +597,12 @@ static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev,

chip = &fwd->chip;

- /*
- * If any of the GPIO lines are sleeping, then the entire forwarder
- * will be sleeping.
- * If any of the chips support .set_config(), then the forwarder will
- * support setting configs.
- */
for (i = 0; i < ngpios; i++) {
- struct gpio_chip *parent = gpiod_to_chip(descs[i]);
-
- dev_dbg(dev, "%u => gpio %d irq %d\n", i,
- desc_to_gpio(descs[i]), gpiod_to_irq(descs[i]));
-
- if (gpiod_cansleep(descs[i]))
- chip->can_sleep = true;
- if (parent && parent->set_config)
- chip->set_config = gpio_fwd_set_config;
+ error = gpiochip_fwd_add_gpio_desc(fwd, descs[i], i);
+ if (error)
+ return ERR_PTR(error);
}

- fwd->descs = descs;
-
if (chip->can_sleep)
mutex_init(&fwd->mlock);
else

--
2.39.5