gpio: move gpio_ensure_requested() into legacy C file

gpio_ensure_requested() only makes sense when using the integer-based
GPIO API, so make sure it is called from there instead of the gpiod
API which we know cannot be called with a non-requested GPIO anyway.

The uses of gpio_ensure_requested() in the gpiod API were kind of
out-of-place anyway, so putting them in gpio-legacy.c helps clearing the
code.

Actually, considering the time this ensure_requested mechanism has been
around, maybe we should just turn this patch into "remove
gpio_ensure_requested()" if we know for sure that no user depend on it
anymore?

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

3 files changed, 113 insertions, 137 deletions

diff --git a/drivers/gpio/gpiolib-legacy.c b/drivers/gpio/gpiolib-legacy.c
index 078ae6c2df79..0f9429b2522a 100644
--- a/drivers/gpio/gpiolib-legacy.c
+++ b/drivers/gpio/gpiolib-legacy.c
@@ -5,6 +5,64 @@
 
 #include "gpiolib.h"
 
+/* Warn when drivers omit gpio_request() calls -- legal but ill-advised
+ * when setting direction, and otherwise illegal.  Until board setup code
+ * and drivers use explicit requests everywhere (which won't happen when
+ * those calls have no teeth) we can't avoid autorequesting.  This nag
+ * message should motivate switching to explicit requests... so should
+ * the weaker cleanup after faults, compared to gpio_request().
+ *
+ * NOTE: the autorequest mechanism is going away; at this point it's
+ * only "legal" in the sense that (old) code using it won't break yet,
+ * but instead only triggers a WARN() stack dump.
+ */
+static int gpio_ensure_requested(struct gpio_desc *desc)
+{
+        struct gpio_chip *chip = desc->chip;
+        unsigned long flags;
+        bool request = false;
+        int err = 0;
+
+        spin_lock_irqsave(&gpio_lock, flags);
+
+        if (WARN(test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0,
+                        "autorequest GPIO-%d\n", desc_to_gpio(desc))) {
+                if (!try_module_get(chip->owner)) {
+                        gpiod_err(desc, "%s: module can't be gotten\n",
+                                        __func__);
+                        clear_bit(FLAG_REQUESTED, &desc->flags);
+                        /* lose */
+                        err = -EIO;
+                        goto end;
+                }
+                desc->label = "[auto]";
+                /* caller must chip->request() w/o spinlock */
+                if (chip->request)
+                        request = true;
+        }
+
+end:
+        spin_unlock_irqrestore(&gpio_lock, flags);
+
+        if (request) {
+                might_sleep_if(chip->can_sleep);
+                err = chip->request(chip, gpio_chip_hwgpio(desc));
+
+                if (err < 0) {
+                        gpiod_dbg(desc, "%s: chip request fail, %d\n",
+                                        __func__, err);
+                        spin_lock_irqsave(&gpio_lock, flags);
+
+                        desc->label = NULL;
+                        clear_bit(FLAG_REQUESTED, &desc->flags);
+
+                        spin_unlock_irqrestore(&gpio_lock, flags);
+                }
+        }
+
+        return err;
+}
+
 void gpio_free(unsigned gpio)
 {
         gpiod_free(gpio_to_desc(gpio));
@@ -100,3 +158,51 @@ void gpio_free_array(const struct gpio *array, size_t num)
                 gpio_free((array++)->gpio);
 }
 EXPORT_SYMBOL_GPL(gpio_free_array);
+
+int gpio_direction_input(unsigned gpio)
+{
+        struct gpio_desc *desc = gpio_to_desc(gpio);
+        int err;
+
+        if (!desc)
+                return -EINVAL;
+
+        err = gpio_ensure_requested(desc);
+        if (err < 0)
+                return err;
+
+        return gpiod_direction_input(desc);
+}
+EXPORT_SYMBOL_GPL(gpio_direction_input);
+
+int gpio_direction_output(unsigned gpio, int value)
+{
+        struct gpio_desc *desc = gpio_to_desc(gpio);
+        int err;
+
+        if (!desc)
+                return -EINVAL;
+
+        err = gpio_ensure_requested(desc);
+        if (err < 0)
+                return err;
+
+        return gpiod_direction_output_raw(desc, value);
+}
+EXPORT_SYMBOL_GPL(gpio_direction_output);
+
+int gpio_set_debounce(unsigned gpio, unsigned debounce)
+{
+        struct gpio_desc *desc = gpio_to_desc(gpio);
+        int err;
+
+        if (!desc)
+                return -EINVAL;
+
+        err = gpio_ensure_requested(desc);
+        if (err < 0)
+                return err;
+
+        return gpiod_set_debounce(desc, debounce);
+}
+EXPORT_SYMBOL_GPL(gpio_set_debounce);
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 7582207c92e7..412d64e93cfb 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -95,39 +95,6 @@ int desc_to_gpio(const struct gpio_desc *desc)
 EXPORT_SYMBOL_GPL(desc_to_gpio);
 
 
-/* Warn when drivers omit gpio_request() calls -- legal but ill-advised
- * when setting direction, and otherwise illegal.  Until board setup code
- * and drivers use explicit requests everywhere (which won't happen when
- * those calls have no teeth) we can't avoid autorequesting.  This nag
- * message should motivate switching to explicit requests... so should
- * the weaker cleanup after faults, compared to gpio_request().
- *
- * NOTE: the autorequest mechanism is going away; at this point it's
- * only "legal" in the sense that (old) code using it won't break yet,
- * but instead only triggers a WARN() stack dump.
- */
-static int gpio_ensure_requested(struct gpio_desc *desc)
-{
-        const struct gpio_chip *chip = desc->chip;
-        const int gpio = desc_to_gpio(desc);
-
-        if (WARN(test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0,
-                        "autorequest GPIO-%d\n", gpio)) {
-                if (!try_module_get(chip->owner)) {
-                        gpiod_err(desc, "%s: module can't be gotten\n",
-                                        __func__);
-                        clear_bit(FLAG_REQUESTED, &desc->flags);
-                        /* lose */
-                        return -EIO;
-                }
-                desc_set_label(desc, "[auto]");
-                /* caller must chip->request() w/o spinlock */
-                if (chip->request)
-                        return 1;
-        }
-        return 0;
-}
-
 /**
  * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
  * @desc:       descriptor to return the chip of
@@ -964,10 +931,8 @@ void gpiochip_free_own_desc(struct gpio_desc *desc)
  */
 int gpiod_direction_input(struct gpio_desc *desc)
 {
-        unsigned long           flags;
         struct gpio_chip        *chip;
         int                     status = -EINVAL;
-        int                     offset;
 
         if (!desc || !desc->chip) {
                 pr_warn("%s: invalid GPIO\n", __func__);
@@ -982,52 +947,20 @@ int gpiod_direction_input(struct gpio_desc *desc)
                 return -EIO;
         }
 
-        spin_lock_irqsave(&gpio_lock, flags);
-
-        status = gpio_ensure_requested(desc);
-        if (status < 0)
-                goto fail;
-
-        /* now we know the gpio is valid and chip won't vanish */
-
-        spin_unlock_irqrestore(&gpio_lock, flags);
-
-        might_sleep_if(chip->can_sleep);
-
-        offset = gpio_chip_hwgpio(desc);
-        if (status) {
-                status = chip->request(chip, offset);
-                if (status < 0) {
-                        gpiod_dbg(desc, "%s: chip request fail, %d\n",
-                                        __func__, status);
-                        /* and it's not available to anyone else ...
-                         * gpio_request() is the fully clean solution.
-                         */
-                        goto lose;
-                }
-        }
-
-        status = chip->direction_input(chip, offset);
+        status = chip->direction_input(chip, gpio_chip_hwgpio(desc));
         if (status == 0)
                 clear_bit(FLAG_IS_OUT, &desc->flags);
 
         trace_gpio_direction(desc_to_gpio(desc), 1, status);
-lose:
-        return status;
-fail:
-        spin_unlock_irqrestore(&gpio_lock, flags);
-        if (status)
-                gpiod_dbg(desc, "%s: status %d\n", __func__, status);
+
         return status;
 }
 EXPORT_SYMBOL_GPL(gpiod_direction_input);
 
 static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value)
 {
-        unsigned long           flags;
         struct gpio_chip        *chip;
         int                     status = -EINVAL;
-        int offset;
 
         /* GPIOs used for IRQs shall not be set as output */
         if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) {
@@ -1053,42 +986,11 @@ static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value)
                 return -EIO;
         }
 
-        spin_lock_irqsave(&gpio_lock, flags);
-
-        status = gpio_ensure_requested(desc);
-        if (status < 0)
-                goto fail;
-
-        /* now we know the gpio is valid and chip won't vanish */
-
-        spin_unlock_irqrestore(&gpio_lock, flags);
-
-        might_sleep_if(chip->can_sleep);
-
-        offset = gpio_chip_hwgpio(desc);
-        if (status) {
-                status = chip->request(chip, offset);
-                if (status < 0) {
-                        gpiod_dbg(desc, "%s: chip request fail, %d\n",
-                                        __func__, status);
-                        /* and it's not available to anyone else ...
-                         * gpio_request() is the fully clean solution.
-                         */
-                        goto lose;
-                }
-        }
-
-        status = chip->direction_output(chip, offset, value);
+        status = chip->direction_output(chip, gpio_chip_hwgpio(desc), value);
         if (status == 0)
                 set_bit(FLAG_IS_OUT, &desc->flags);
         trace_gpio_value(desc_to_gpio(desc), 0, value);
         trace_gpio_direction(desc_to_gpio(desc), 0, status);
-lose:
-        return status;
-fail:
-        spin_unlock_irqrestore(&gpio_lock, flags);
-        if (status)
-                gpiod_dbg(desc, "%s: gpio status %d\n", __func__, status);
         return status;
 }
 
@@ -1147,10 +1049,7 @@ EXPORT_SYMBOL_GPL(gpiod_direction_output);
  */
 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
 {
-        unsigned long           flags;
         struct gpio_chip        *chip;
-        int                     status = -EINVAL;
-        int                     offset;
 
         if (!desc || !desc->chip) {
                 pr_warn("%s: invalid GPIO\n", __func__);
@@ -1165,27 +1064,7 @@ int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
                 return -ENOTSUPP;
         }
 
-        spin_lock_irqsave(&gpio_lock, flags);
-
-        status = gpio_ensure_requested(desc);
-        if (status < 0)
-                goto fail;
-
-        /* now we know the gpio is valid and chip won't vanish */
-
-        spin_unlock_irqrestore(&gpio_lock, flags);
-
-        might_sleep_if(chip->can_sleep);
-
-        offset = gpio_chip_hwgpio(desc);
-        return chip->set_debounce(chip, offset, debounce);
-
-fail:
-        spin_unlock_irqrestore(&gpio_lock, flags);
-        if (status)
-                gpiod_dbg(desc, "%s: status %d\n", __func__, status);
-
-        return status;
+        return chip->set_debounce(chip, gpio_chip_hwgpio(desc), debounce);
 }
 EXPORT_SYMBOL_GPL(gpiod_set_debounce);
 
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index c1d4105e1c1d..39a1d06950d9 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -63,19 +63,10 @@ static inline struct gpio_chip *gpio_to_chip(unsigned gpio)
 extern int gpio_request(unsigned gpio, const char *label);
 extern void gpio_free(unsigned gpio);
 
-static inline int gpio_direction_input(unsigned gpio)
-{
-        return gpiod_direction_input(gpio_to_desc(gpio));
-}
-static inline int gpio_direction_output(unsigned gpio, int value)
-{
-        return gpiod_direction_output_raw(gpio_to_desc(gpio), value);
-}
+extern int gpio_direction_input(unsigned gpio);
+extern int gpio_direction_output(unsigned gpio, int value);
 
-static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
-{
-        return gpiod_set_debounce(gpio_to_desc(gpio), debounce);
-}
+extern int gpio_set_debounce(unsigned gpio, unsigned debounce);
 
 static inline int gpio_get_value_cansleep(unsigned gpio)
 {