6 files changed, 128 insertions, 31 deletions

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 572d372899d3..faa1cc66e9cf 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -67,17 +67,28 @@ static inline void desc_set_label(struct gpio_desc *d, const char *label)
  * 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...
+ * message should motivate switching to explicit requests... so should
+ * the weaker cleanup after faults, compared to gpio_request().
  */
-static void gpio_ensure_requested(struct gpio_desc *desc)
+static int gpio_ensure_requested(struct gpio_desc *desc, unsigned offset)
 {
         if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
-                pr_warning("GPIO-%d autorequested\n", (int)(desc - gpio_desc));
+                struct gpio_chip *chip = desc->chip;
+                int gpio = chip->base + offset;
+
+                if (!try_module_get(chip->owner)) {
+                        pr_err("GPIO-%d: module can't be gotten \n", gpio);
+                        clear_bit(FLAG_REQUESTED, &desc->flags);
+                        /* lose */
+                        return -EIO;
+                }
+                pr_warning("GPIO-%d autorequested\n", gpio);
                 desc_set_label(desc, "[auto]");
-                if (!try_module_get(desc->chip->owner))
-                        pr_err("GPIO-%d: module can't be gotten \n",
-                                        (int)(desc - gpio_desc));
+                /* caller must chip->request() w/o spinlock */
+                if (chip->request)
+                        return 1;
         }
+        return 0;
 }
 
 /* caller holds gpio_lock *OR* gpio is marked as requested */
@@ -237,7 +248,7 @@ static ssize_t gpio_value_show(struct device *dev,
         if (!test_bit(FLAG_EXPORT, &desc->flags))
                 status = -EIO;
         else
-                status = sprintf(buf, "%d\n", gpio_get_value_cansleep(gpio));
+                status = sprintf(buf, "%d\n", !!gpio_get_value_cansleep(gpio));
 
         mutex_unlock(&sysfs_lock);
         return status;
@@ -752,6 +763,7 @@ EXPORT_SYMBOL_GPL(gpiochip_remove);
 int gpio_request(unsigned gpio, const char *label)
 {
         struct gpio_desc        *desc;
+        struct gpio_chip        *chip;
         int                     status = -EINVAL;
         unsigned long           flags;
 
@@ -760,14 +772,15 @@ int gpio_request(unsigned gpio, const char *label)
         if (!gpio_is_valid(gpio))
                 goto done;
         desc = &gpio_desc[gpio];
-        if (desc->chip == NULL)
+        chip = desc->chip;
+        if (chip == NULL)
                 goto done;
 
-        if (!try_module_get(desc->chip->owner))
+        if (!try_module_get(chip->owner))
                 goto done;
 
         /* NOTE:  gpio_request() can be called in early boot,
-         * before IRQs are enabled.
+         * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
          */
 
         if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
@@ -775,7 +788,20 @@ int gpio_request(unsigned gpio, const char *label)
                 status = 0;
         } else {
                 status = -EBUSY;
-                module_put(desc->chip->owner);
+                module_put(chip->owner);
+        }
+
+        if (chip->request) {
+                /* chip->request may sleep */
+                spin_unlock_irqrestore(&gpio_lock, flags);
+                status = chip->request(chip, gpio - chip->base);
+                spin_lock_irqsave(&gpio_lock, flags);
+
+                if (status < 0) {
+                        desc_set_label(desc, NULL);
+                        module_put(chip->owner);
+                        clear_bit(FLAG_REQUESTED, &desc->flags);
+                }
         }
 
 done:
@@ -791,6 +817,9 @@ void gpio_free(unsigned gpio)
 {
         unsigned long           flags;
         struct gpio_desc        *desc;
+        struct gpio_chip        *chip;
+
+        might_sleep();
 
         if (!gpio_is_valid(gpio)) {
                 WARN_ON(extra_checks);
@@ -802,9 +831,17 @@ void gpio_free(unsigned gpio)
         spin_lock_irqsave(&gpio_lock, flags);
 
         desc = &gpio_desc[gpio];
-        if (desc->chip && test_and_clear_bit(FLAG_REQUESTED, &desc->flags)) {
+        chip = desc->chip;
+        if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
+                if (chip->free) {
+                        spin_unlock_irqrestore(&gpio_lock, flags);
+                        might_sleep_if(extra_checks && chip->can_sleep);
+                        chip->free(chip, gpio - chip->base);
+                        spin_lock_irqsave(&gpio_lock, flags);
+                }
                 desc_set_label(desc, NULL);
                 module_put(desc->chip->owner);
+                clear_bit(FLAG_REQUESTED, &desc->flags);
         } else
                 WARN_ON(extra_checks);
 
@@ -869,7 +906,9 @@ int gpio_direction_input(unsigned gpio)
         gpio -= chip->base;
         if (gpio >= chip->ngpio)
                 goto fail;
-        gpio_ensure_requested(desc);
+        status = gpio_ensure_requested(desc, gpio);
+        if (status < 0)
+                goto fail;
 
         /* now we know the gpio is valid and chip won't vanish */
 
@@ -877,9 +916,22 @@ int gpio_direction_input(unsigned gpio)
 
         might_sleep_if(extra_checks && chip->can_sleep);
 
+        if (status) {
+                status = chip->request(chip, gpio);
+                if (status < 0) {
+                        pr_debug("GPIO-%d: chip request fail, %d\n",
+                                chip->base + gpio, status);
+                        /* and it's not available to anyone else ...
+                         * gpio_request() is the fully clean solution.
+                         */
+                        goto lose;
+                }
+        }
+
         status = chip->direction_input(chip, gpio);
         if (status == 0)
                 clear_bit(FLAG_IS_OUT, &desc->flags);
+lose:
         return status;
 fail:
         spin_unlock_irqrestore(&gpio_lock, flags);
@@ -907,7 +959,9 @@ int gpio_direction_output(unsigned gpio, int value)
         gpio -= chip->base;
         if (gpio >= chip->ngpio)
                 goto fail;
-        gpio_ensure_requested(desc);
+        status = gpio_ensure_requested(desc, gpio);
+        if (status < 0)
+                goto fail;
 
         /* now we know the gpio is valid and chip won't vanish */
 
@@ -915,9 +969,22 @@ int gpio_direction_output(unsigned gpio, int value)
 
         might_sleep_if(extra_checks && chip->can_sleep);
 
+        if (status) {
+                status = chip->request(chip, gpio);
+                if (status < 0) {
+                        pr_debug("GPIO-%d: chip request fail, %d\n",
+                                chip->base + gpio, status);
+                        /* and it's not available to anyone else ...
+                         * gpio_request() is the fully clean solution.
+                         */
+                        goto lose;
+                }
+        }
+
         status = chip->direction_output(chip, gpio, value);
         if (status == 0)
                 set_bit(FLAG_IS_OUT, &desc->flags);
+lose:
         return status;
 fail:
         spin_unlock_irqrestore(&gpio_lock, flags);
@@ -1008,6 +1075,24 @@ int __gpio_cansleep(unsigned gpio)
 }
 EXPORT_SYMBOL_GPL(__gpio_cansleep);
 
+/**
+ * __gpio_to_irq() - return the IRQ corresponding to a GPIO
+ * @gpio: gpio whose IRQ will be returned (already requested)
+ * Context: any
+ *
+ * This is used directly or indirectly to implement gpio_to_irq().
+ * It returns the number of the IRQ signaled by this (input) GPIO,
+ * or a negative errno.
+ */
+int __gpio_to_irq(unsigned gpio)
+{
+        struct gpio_chip        *chip;
+
+        chip = gpio_to_chip(gpio);
+        return chip->to_irq ? chip->to_irq(chip, gpio - chip->base) : -ENXIO;
+}
+EXPORT_SYMBOL_GPL(__gpio_to_irq);
+
 
 
 /* There's no value in making it easy to inline GPIO calls that may sleep.
@@ -1020,7 +1105,7 @@ int gpio_get_value_cansleep(unsigned gpio)
 
         might_sleep_if(extra_checks);
         chip = gpio_to_chip(gpio);
-        return chip->get(chip, gpio - chip->base);
+        return chip->get ? chip->get(chip, gpio - chip->base) : 0;
 }
 EXPORT_SYMBOL_GPL(gpio_get_value_cansleep);
 
diff --git a/drivers/gpio/max7301.c b/drivers/gpio/max7301.c
index 39c795ad8312..8b24d784db93 100644
--- a/drivers/gpio/max7301.c
+++ b/drivers/gpio/max7301.c
@@ -255,10 +255,6 @@ static int __devinit max7301_probe(struct spi_device *spi)
         ts->chip.dev = &spi->dev;
         ts->chip.owner = THIS_MODULE;
 
-        ret = gpiochip_add(&ts->chip);
-        if (ret)
-                goto exit_destroy;
-
         /*
          * tristate all pins in hardware and cache the
          * register values for later use.
@@ -269,17 +265,19 @@ static int __devinit max7301_probe(struct spi_device *spi)
                 max7301_write(spi, 0x08 + i, 0xAA);
                 ts->port_config[i] = 0xAA;
                 for (j = 0; j < 4; j++) {
-                        int idx = ts->chip.base + (i - 1) * 4 + j;
-                        ret = gpio_direction_input(idx);
+                        int offset = (i - 1) * 4 + j;
+                        ret = max7301_direction_input(&ts->chip, offset);
                         if (ret)
-                                goto exit_remove;
-                        gpio_free(idx);
+                                goto exit_destroy;
                 }
         }
+
+        ret = gpiochip_add(&ts->chip);
+        if (ret)
+                goto exit_destroy;
+
         return ret;
 
-exit_remove:
-        gpiochip_remove(&ts->chip);
 exit_destroy:
         dev_set_drvdata(&spi->dev, NULL);
         mutex_destroy(&ts->lock);
@@ -325,13 +323,15 @@ static int __init max7301_init(void)
 {
         return spi_register_driver(&max7301_driver);
 }
+/* register after spi postcore initcall and before
+ * subsys initcalls that may rely on these GPIOs
+ */
+subsys_initcall(max7301_init);
 
 static void __exit max7301_exit(void)
 {
         spi_unregister_driver(&max7301_driver);
 }
-
-module_init(max7301_init);
 module_exit(max7301_exit);
 
 MODULE_AUTHOR("Juergen Beisert");
diff --git a/drivers/gpio/max732x.c b/drivers/gpio/max732x.c
index b51c8135ca28..55ae9a41897a 100644
--- a/drivers/gpio/max732x.c
+++ b/drivers/gpio/max732x.c
@@ -372,7 +372,10 @@ static int __init max732x_init(void)
 {
         return i2c_add_driver(&max732x_driver);
 }
-module_init(max732x_init);
+/* register after i2c postcore initcall and before
+ * subsys initcalls that may rely on these GPIOs
+ */
+subsys_initcall(max732x_init);
 
 static void __exit max732x_exit(void)
 {
diff --git a/drivers/gpio/mcp23s08.c b/drivers/gpio/mcp23s08.c
index 8a1b405fefda..89c1d222e9d1 100644
--- a/drivers/gpio/mcp23s08.c
+++ b/drivers/gpio/mcp23s08.c
@@ -419,7 +419,10 @@ static int __init mcp23s08_init(void)
 {
         return spi_register_driver(&mcp23s08_driver);
 }
-module_init(mcp23s08_init);
+/* register after spi postcore initcall and before
+ * subsys initcalls that may rely on these GPIOs
+ */
+subsys_initcall(mcp23s08_init);
 
 static void __exit mcp23s08_exit(void)
 {
diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c
index cc8468692ae0..9ceeb89f1325 100644
--- a/drivers/gpio/pca953x.c
+++ b/drivers/gpio/pca953x.c
@@ -289,7 +289,10 @@ static int __init pca953x_init(void)
 {
         return i2c_add_driver(&pca953x_driver);
 }
-module_init(pca953x_init);
+/* register after i2c postcore initcall and before
+ * subsys initcalls that may rely on these GPIOs
+ */
+subsys_initcall(pca953x_init);
 
 static void __exit pca953x_exit(void)
 {
diff --git a/drivers/gpio/pcf857x.c b/drivers/gpio/pcf857x.c
index fc9c6ae739ee..4bc2070dd4a1 100644
--- a/drivers/gpio/pcf857x.c
+++ b/drivers/gpio/pcf857x.c
@@ -351,7 +351,10 @@ static int __init pcf857x_init(void)
 {
         return i2c_add_driver(&pcf857x_driver);
 }
-module_init(pcf857x_init);
+/* register after i2c postcore initcall and before
+ * subsys initcalls that may rely on these GPIOs
+ */
+subsys_initcall(pcf857x_init);
 
 static void __exit pcf857x_exit(void)
 {