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path: root/drivers/gpio/gpiolib.c
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Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r--drivers/gpio/gpiolib.c63
1 files changed, 11 insertions, 52 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 199fca1..e14eb88 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -52,14 +52,13 @@ struct gpio_desc {
/* flag symbols are bit numbers */
#define FLAG_REQUESTED 0
#define FLAG_IS_OUT 1
-#define FLAG_RESERVED 2
-#define FLAG_EXPORT 3 /* protected by sysfs_lock */
-#define FLAG_SYSFS 4 /* exported via /sys/class/gpio/control */
-#define FLAG_TRIG_FALL 5 /* trigger on falling edge */
-#define FLAG_TRIG_RISE 6 /* trigger on rising edge */
-#define FLAG_ACTIVE_LOW 7 /* sysfs value has active low */
-#define FLAG_OPEN_DRAIN 8 /* Gpio is open drain type */
-#define FLAG_OPEN_SOURCE 9 /* Gpio is open source type */
+#define FLAG_EXPORT 2 /* protected by sysfs_lock */
+#define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */
+#define FLAG_TRIG_FALL 4 /* trigger on falling edge */
+#define FLAG_TRIG_RISE 5 /* trigger on rising edge */
+#define FLAG_ACTIVE_LOW 6 /* sysfs value has active low */
+#define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */
+#define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */
#define ID_SHIFT 16 /* add new flags before this one */
@@ -132,7 +131,7 @@ static int gpiochip_find_base(int ngpio)
struct gpio_desc *desc = &gpio_desc[i];
struct gpio_chip *chip = desc->chip;
- if (!chip && !test_bit(FLAG_RESERVED, &desc->flags)) {
+ if (!chip) {
spare++;
if (spare == ngpio) {
base = i;
@@ -150,47 +149,6 @@ static int gpiochip_find_base(int ngpio)
return base;
}
-/**
- * gpiochip_reserve() - reserve range of gpios to use with platform code only
- * @start: starting gpio number
- * @ngpio: number of gpios to reserve
- * Context: platform init, potentially before irqs or kmalloc will work
- *
- * Returns a negative errno if any gpio within the range is already reserved
- * or registered, else returns zero as a success code. Use this function
- * to mark a range of gpios as unavailable for dynamic gpio number allocation,
- * for example because its driver support is not yet loaded.
- */
-int __init gpiochip_reserve(int start, int ngpio)
-{
- int ret = 0;
- unsigned long flags;
- int i;
-
- if (!gpio_is_valid(start) || !gpio_is_valid(start + ngpio - 1))
- return -EINVAL;
-
- spin_lock_irqsave(&gpio_lock, flags);
-
- for (i = start; i < start + ngpio; i++) {
- struct gpio_desc *desc = &gpio_desc[i];
-
- if (desc->chip || test_bit(FLAG_RESERVED, &desc->flags)) {
- ret = -EBUSY;
- goto err;
- }
-
- set_bit(FLAG_RESERVED, &desc->flags);
- }
-
- pr_debug("%s: reserved gpios from %d to %d\n",
- __func__, start, start + ngpio - 1);
-err:
- spin_unlock_irqrestore(&gpio_lock, flags);
-
- return ret;
-}
-
/* caller ensures gpio is valid and requested, chip->get_direction may sleep */
static int gpio_get_direction(unsigned gpio)
{
@@ -254,13 +212,14 @@ static ssize_t gpio_direction_show(struct device *dev,
mutex_lock(&sysfs_lock);
- if (!test_bit(FLAG_EXPORT, &desc->flags))
+ if (!test_bit(FLAG_EXPORT, &desc->flags)) {
status = -EIO;
- else
+ } else {
gpio_get_direction(gpio);
status = sprintf(buf, "%s\n",
test_bit(FLAG_IS_OUT, &desc->flags)
? "out" : "in");
+ }
mutex_unlock(&sysfs_lock);
return status;