gpio: sysfs: remove redundant export tests

The attribute operations will never be called for an unregistered device
so remove redundant checks for FLAG_EXPORT.

Note that kernfs will also guarantee that any active sysfs operation has
finished before the attribute is removed during deregistration.

Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 23 insertions, 51 deletions

diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index e4b079eec9bc..10baf31efe74 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -46,14 +46,10 @@ static ssize_t direction_show(struct device *dev,
 
         mutex_lock(&sysfs_lock);
 
-        if (!test_bit(FLAG_EXPORT, &desc->flags)) {
-                status = -EIO;
-        } else {
-                gpiod_get_direction(desc);
-                status = sprintf(buf, "%s\n",
+        gpiod_get_direction(desc);
+        status = sprintf(buf, "%s\n",
                         test_bit(FLAG_IS_OUT, &desc->flags)
                                 ? "out" : "in");
-        }
 
         mutex_unlock(&sysfs_lock);
         return status;
@@ -67,9 +63,7 @@ static ssize_t direction_store(struct device *dev,
 
         mutex_lock(&sysfs_lock);
 
-        if (!test_bit(FLAG_EXPORT, &desc->flags))
-                status = -EIO;
-        else if (sysfs_streq(buf, "high"))
+        if (sysfs_streq(buf, "high"))
                 status = gpiod_direction_output_raw(desc, 1);
         else if (sysfs_streq(buf, "out") || sysfs_streq(buf, "low"))
                 status = gpiod_direction_output_raw(desc, 0);
@@ -91,10 +85,7 @@ static ssize_t value_show(struct device *dev,
 
         mutex_lock(&sysfs_lock);
 
-        if (!test_bit(FLAG_EXPORT, &desc->flags))
-                status = -EIO;
-        else
-                status = sprintf(buf, "%d\n", gpiod_get_value_cansleep(desc));
+        status = sprintf(buf, "%d\n", gpiod_get_value_cansleep(desc));
 
         mutex_unlock(&sysfs_lock);
         return status;
@@ -108,11 +99,9 @@ static ssize_t value_store(struct device *dev,
 
         mutex_lock(&sysfs_lock);
 
-        if (!test_bit(FLAG_EXPORT, &desc->flags))
-                status = -EIO;
-        else if (!test_bit(FLAG_IS_OUT, &desc->flags))
+        if (!test_bit(FLAG_IS_OUT, &desc->flags)) {
                 status = -EPERM;
-        else {
+        } else {
                 long            value;
 
                 status = kstrtol(buf, 0, &value);
@@ -237,23 +226,18 @@ static ssize_t edge_show(struct device *dev,
                 struct device_attribute *attr, char *buf)
 {
         const struct gpio_desc  *desc = dev_get_drvdata(dev);
-        ssize_t                 status;
+        unsigned long mask;
+        ssize_t status = 0;
+        int i;
 
         mutex_lock(&sysfs_lock);
 
-        if (!test_bit(FLAG_EXPORT, &desc->flags))
-                status = -EIO;
-        else {
-                int i;
-
-                status = 0;
-                for (i = 0; i < ARRAY_SIZE(trigger_types); i++)
-                        if ((desc->flags & GPIO_TRIGGER_MASK)
-                                        == trigger_types[i].flags) {
-                                status = sprintf(buf, "%s\n",
-                                                 trigger_types[i].name);
-                                break;
-                        }
+        for (i = 0; i < ARRAY_SIZE(trigger_types); i++) {
+                mask = desc->flags & GPIO_TRIGGER_MASK;
+                if (mask == trigger_types[i].flags) {
+                        status = sprintf(buf, "%s\n", trigger_types[i].name);
+                        break;
+                }
         }
 
         mutex_unlock(&sysfs_lock);
@@ -275,13 +259,9 @@ static ssize_t edge_store(struct device *dev,
 found:
         mutex_lock(&sysfs_lock);
 
-        if (!test_bit(FLAG_EXPORT, &desc->flags))
-                status = -EIO;
-        else {
-                status = gpio_setup_irq(desc, dev, trigger_types[i].flags);
-                if (!status)
-                        status = size;
-        }
+        status = gpio_setup_irq(desc, dev, trigger_types[i].flags);
+        if (!status)
+                status = size;
 
         mutex_unlock(&sysfs_lock);
 
@@ -322,10 +302,7 @@ static ssize_t active_low_show(struct device *dev,
 
         mutex_lock(&sysfs_lock);
 
-        if (!test_bit(FLAG_EXPORT, &desc->flags))
-                status = -EIO;
-        else
-                status = sprintf(buf, "%d\n",
+        status = sprintf(buf, "%d\n",
                                 !!test_bit(FLAG_ACTIVE_LOW, &desc->flags));
 
         mutex_unlock(&sysfs_lock);
@@ -338,18 +315,13 @@ static ssize_t active_low_store(struct device *dev,
 {
         struct gpio_desc        *desc = dev_get_drvdata(dev);
         ssize_t                 status;
+        long                    value;
 
         mutex_lock(&sysfs_lock);
 
-        if (!test_bit(FLAG_EXPORT, &desc->flags)) {
-                status = -EIO;
-        } else {
-                long            value;
-
-                status = kstrtol(buf, 0, &value);
-                if (status == 0)
-                        status = sysfs_set_active_low(desc, dev, value != 0);
-        }
+        status = kstrtol(buf, 0, &value);
+        if (status == 0)
+                status = sysfs_set_active_low(desc, dev, value != 0);
 
         mutex_unlock(&sysfs_lock);