[PATCH] gpiolib: fix find_chip_by_name()

[PATCH] gpiolib: fix find_chip_by_name()

[Alexandre Courbot]

find_chip_by_name() was incorrectly implemented by using
gpio_lookup_list instead of gpiod_chips to iterate through all the
registered GPIO controllers. This patch reimplements it by using
gpiochip_find() with a custom search function, which simplifies the code
on top of fixing the mistake.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
---
 drivers/gpio/gpiolib.c | 29 ++++++++++++-----------------
 1 file changed, 12 insertions(+), 17 deletions(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 9f3326b..63bbf5b 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1307,6 +1307,18 @@ struct gpio_chip *gpiochip_find(void *data,
 }
 EXPORT_SYMBOL_GPL(gpiochip_find);
 
+static int gpiochip_match_name(struct gpio_chip *chip, void *data)
+{
+	const char *name = data;
+
+	return !strcmp(chip->label, name);
+}
+
+static struct gpio_chip *find_chip_by_name(const char *name)
+{
+	return gpiochip_find((void *)name, gpiochip_match_name);
+}
+
 #ifdef CONFIG_PINCTRL
 
 /**
@@ -2212,23 +2224,6 @@ void gpiod_add_table(struct gpiod_lookup *table, size_t size)
 	mutex_unlock(&gpio_lookup_lock);
 }
 
-/*
- * Caller must have a acquired gpio_lookup_lock
- */
-static struct gpio_chip *find_chip_by_name(const char *name)
-{
-	struct gpio_chip *chip = NULL;
-
-	list_for_each_entry(chip, &gpio_lookup_list, list) {
-		if (chip->label == NULL)
-			continue;
-		if (!strcmp(chip->label, name))
-			break;
-	}
-
-	return chip;
-}
-
 #ifdef CONFIG_OF
 static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
 				      unsigned int idx, unsigned long *flags)
-- 
1.8.4.2

Re: [PATCH] gpiolib: fix find_chip_by_name()

[Linus Walleij]

On Sat, Nov 16, 2013 at 1:39 PM, Alexandre Courbot <acourbot@nvidia.com> wrote:

> find_chip_by_name() was incorrectly implemented by using
> gpio_lookup_list instead of gpiod_chips to iterate through all the
> registered GPIO controllers. This patch reimplements it by using
> gpiochip_find() with a custom search function, which simplifies the code
> on top of fixing the mistake.
>
> Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>

Patch applied for fixes.

Yours,
Linus Walleij