[PATCH v1 3/3] gpiolib: sysfs: Simplify edge handling in the code

From: Andy Shevchenko
Date: Wed Feb 09 2022 - 07:05:36 EST


Instead of keeping specific data structure for IRQ trigger types, switch
to array of trigger names and use index as a type.

The code is in maintenance mode and that array is not going to grow.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/gpio/gpiolib-sysfs.c | 40 +++++++++++++-----------------------
1 file changed, 14 insertions(+), 26 deletions(-)

diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index e7828d4dc7a8..d44ffea038f5 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -13,6 +13,7 @@
#include "gpiolib.h"
#include "gpiolib-sysfs.h"

+#define GPIO_IRQF_TRIGGER_NONE 0
#define GPIO_IRQF_TRIGGER_FALLING BIT(0)
#define GPIO_IRQF_TRIGGER_RISING BIT(1)
#define GPIO_IRQF_TRIGGER_BOTH (GPIO_IRQF_TRIGGER_FALLING | \
@@ -218,54 +219,41 @@ static void gpio_sysfs_free_irq(struct device *dev)
sysfs_put(data->value_kn);
}

-static const struct {
- const char *name;
- unsigned char flags;
-} trigger_types[] = {
- { "none", 0 },
- { "falling", GPIO_IRQF_TRIGGER_FALLING },
- { "rising", GPIO_IRQF_TRIGGER_RISING },
- { "both", GPIO_IRQF_TRIGGER_BOTH },
+static const char * const trigger_names[] = {
+ [GPIO_IRQF_TRIGGER_NONE] = "none",
+ [GPIO_IRQF_TRIGGER_FALLING] = "falling",
+ [GPIO_IRQF_TRIGGER_RISING] = "rising",
+ [GPIO_IRQF_TRIGGER_BOTH] = "both",
};

static ssize_t edge_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct gpiod_data *data = dev_get_drvdata(dev);
- int i;
+ int flags;

mutex_lock(&data->mutex);

- for (i = 0; i < ARRAY_SIZE(trigger_types); i++) {
- if (data->irq_flags == trigger_types[i].flags)
- break;
- }
+ flags = data->irq_flags;

mutex_unlock(&data->mutex);

- if (i >= ARRAY_SIZE(trigger_types))
+ if (flags >= ARRAY_SIZE(trigger_names))
return 0;

- return sysfs_emit(buf, "%s\n", trigger_types[i].name);
+ return sysfs_emit(buf, "%s\n", trigger_names[flags]);
}

static ssize_t edge_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct gpiod_data *data = dev_get_drvdata(dev);
- unsigned char flags;
ssize_t status = size;
- int i;
-
- for (i = 0; i < ARRAY_SIZE(trigger_types); i++) {
- if (sysfs_streq(trigger_types[i].name, buf))
- break;
- }
-
- if (i == ARRAY_SIZE(trigger_types))
- return -EINVAL;
+ int flags;

- flags = trigger_types[i].flags;
+ flags = sysfs_match_string(trigger_names, buf);
+ if (flags < 0)
+ return flags;

mutex_lock(&data->mutex);

--
2.34.1