*/
int twl4030_request_gpio(int gpio)
{
- int ret = 0;
-
if (unlikely(gpio >= TWL4030_GPIO_MAX))
return -EPERM;
- ret = gpio_request(twl_gpiochip.base + gpio, NULL);
- if (ret < 0)
- return ret;
-
- mutex_lock(&gpio_lock);
- if (gpio_usage_count & BIT(gpio)) {
- ret = -EBUSY;
- } else {
- /* First time usage? - switch on GPIO module */
- if (!gpio_usage_count) {
- ret = gpio_twl4030_write(REG_GPIO_CTRL,
- MASK_GPIO_CTRL_GPIO_ON);
-
- }
- if (!ret)
- gpio_usage_count |= BIT(gpio);
- else
- gpio_free(twl_gpiochip.base + gpio);
- }
- mutex_unlock(&gpio_lock);
- return ret;
+ return gpio_request(twl_gpiochip.base + gpio, NULL);
}
EXPORT_SYMBOL(twl4030_request_gpio);
*/
int twl4030_free_gpio(int gpio)
{
- int ret = 0;
-
if (unlikely(gpio >= TWL4030_GPIO_MAX))
return -EPERM;
- mutex_lock(&gpio_lock);
-
- if ((gpio_usage_count & BIT(gpio)) == 0) {
- ret = -EPERM;
- } else {
- gpio_usage_count &= ~BIT(gpio);
- gpio_free(twl_gpiochip.base + gpio);
- }
-
- /* Last time usage? - switch off GPIO module */
- if (ret == 0 && !gpio_usage_count)
- ret = gpio_twl4030_write(REG_GPIO_CTRL, 0x0);
-
- mutex_unlock(&gpio_lock);
- return ret;
+ gpio_free(twl_gpiochip.base + gpio);
+ return 0;
}
EXPORT_SYMBOL(twl4030_free_gpio);
/*----------------------------------------------------------------------*/
+static int twl_request(struct gpio_chip *chip, unsigned offset)
+{
+ int status = 0;
+
+ mutex_lock(&gpio_lock);
+
+ /* on first use, turn GPIO module "on" */
+ if (!gpio_usage_count)
+ status = gpio_twl4030_write(REG_GPIO_CTRL,
+ MASK_GPIO_CTRL_GPIO_ON);
+
+ if (!status)
+ gpio_usage_count |= (0x1 << offset);
+
+done:
+ mutex_unlock(&gpio_lock);
+ return status;
+}
+
+static void twl_free(struct gpio_chip *chip, unsigned offset)
+{
+ mutex_lock(&gpio_lock);
+
+ gpio_usage_count &= ~BIT(offset);
+
+ /* on last use, switch off GPIO module */
+ if (!gpio_usage_count)
+ gpio_twl4030_write(REG_GPIO_CTRL, 0x0);
+
+ mutex_unlock(&gpio_lock);
+}
+
static int twl_direction_in(struct gpio_chip *chip, unsigned offset)
{
return twl4030_set_gpio_direction(offset, 1);
static struct gpio_chip twl_gpiochip = {
.label = "twl4030",
.owner = THIS_MODULE,
+ .request = twl_request,
+ .free = twl_free,
.direction_input = twl_direction_in,
.get = twl_get,
.direction_output = twl_direction_out,