Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux

Pull GPIO changes from Grant Likely:
 "This branch contains the usual set of individual driver improvements
  and bug fixes, as well as updates to the core code.  The more notable
  changes include:

   - Internally add new API for referencing GPIOs by gpio_desc instead
     of number.  Eventually this will become a public API

   - ACPI GPIO binding support"

* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux: (33 commits)
  arm64: select ARCH_WANT_OPTIONAL_GPIOLIB
  gpio: em: Use irq_domain_add_simple() to fix runtime error
  gpio: using common order: let 'static const' instead of 'const static'
  gpio/vt8500: memory cleanup missing
  gpiolib: Fix locking on gpio debugfs files
  gpiolib: let gpio_chip reference its descriptors
  gpiolib: use descriptors internally
  gpiolib: use gpio_chips list in gpiochip_find_base
  gpiolib: use gpio_chips list in sysfs ops
  gpiolib: use gpio_chips list in gpiochip_find
  gpiolib: use gpio_chips list in gpiolib_sysfs_init
  gpiolib: link all gpio_chips using a list
  gpio/langwell: cleanup driver
  gpio/langwell: Add Cloverview ids to pci device table
  gpio/lynxpoint: add chipset gpio driver.
  gpiolib: add missing braces in gpio_direction_show
  gpiolib-acpi: Fix error checks in interrupt requesting
  gpio: mpc8xxx: don't set IRQ_TYPE_NONE when creating irq mapping
  gpiolib: remove gpiochip_reserve()
  arm: pxa: tosa: do not use gpiochip_reserve()
  ...

1 files changed, 112 insertions, 64 deletions

diff --git a/drivers/gpio/gpio-twl4030.c b/drivers/gpio/gpio-twl4030.c
index 9572aa137e6f..4d330e36da1d 100644
--- a/drivers/gpio/gpio-twl4030.c
+++ b/drivers/gpio/gpio-twl4030.c
@@ -37,7 +37,6 @@
 
 #include <linux/i2c/twl.h>
 
-
 /*
  * The GPIO "subchip" supports 18 GPIOs which can be configured as
  * inputs or outputs, with pullups or pulldowns on each pin.  Each
@@ -49,11 +48,6 @@
  * There are also two LED pins used sometimes as output-only GPIOs.
  */
 
-
-static struct gpio_chip twl_gpiochip;
-static int twl4030_gpio_base;
-static int twl4030_gpio_irq_base;
-
 /* genirq interfaces are not available to modules */
 #ifdef MODULE
 #define is_module()     true
@@ -69,14 +63,24 @@ static int twl4030_gpio_irq_base;
 /* Mask for GPIO registers when aggregated into a 32-bit integer */
 #define GPIO_32_MASK                    0x0003ffff
 
-/* Data structures */
-static DEFINE_MUTEX(gpio_lock);
+struct gpio_twl4030_priv {
+        struct gpio_chip gpio_chip;
+        struct mutex mutex;
+        int irq_base;
 
-/* store usage of each GPIO. - each bit represents one GPIO */
-static unsigned int gpio_usage_count;
+        /* Bitfields for state caching */
+        unsigned int usage_count;
+        unsigned int direction;
+        unsigned int out_state;
+};
 
 /*----------------------------------------------------------------------*/
 
+static inline struct gpio_twl4030_priv *to_gpio_twl4030(struct gpio_chip *chip)
+{
+        return container_of(chip, struct gpio_twl4030_priv, gpio_chip);
+}
+
 /*
  * To configure TWL4030 GPIO module registers
  */
@@ -126,7 +130,7 @@ static inline int gpio_twl4030_read(u8 address)
 
 /*----------------------------------------------------------------------*/
 
-static u8 cached_leden;         /* protected by gpio_lock */
+static u8 cached_leden;
 
 /* The LED lines are open drain outputs ... a FET pulls to GND, so an
  * external pullup is needed.  We could also expose the integrated PWM
@@ -140,14 +144,12 @@ static void twl4030_led_set_value(int led, int value)
         if (led)
                 mask <<= 1;
 
-        mutex_lock(&gpio_lock);
         if (value)
                 cached_leden &= ~mask;
         else
                 cached_leden |= mask;
         status = twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden,
                                   TWL4030_LED_LEDEN_REG);
-        mutex_unlock(&gpio_lock);
 }
 
 static int twl4030_set_gpio_direction(int gpio, int is_input)
@@ -158,7 +160,6 @@ static int twl4030_set_gpio_direction(int gpio, int is_input)
         u8 base = REG_GPIODATADIR1 + d_bnk;
         int ret = 0;
 
-        mutex_lock(&gpio_lock);
         ret = gpio_twl4030_read(base);
         if (ret >= 0) {
                 if (is_input)
@@ -168,7 +169,6 @@ static int twl4030_set_gpio_direction(int gpio, int is_input)
 
                 ret = gpio_twl4030_write(base, reg);
         }
-        mutex_unlock(&gpio_lock);
         return ret;
 }
 
@@ -193,10 +193,6 @@ static int twl4030_get_gpio_datain(int gpio)
         u8 base = 0;
         int ret = 0;
 
-        if (unlikely((gpio >= TWL4030_GPIO_MAX)
-                || !(gpio_usage_count & BIT(gpio))))
-                return -EPERM;
-
         base = REG_GPIODATAIN1 + d_bnk;
         ret = gpio_twl4030_read(base);
         if (ret > 0)
@@ -209,9 +205,10 @@ static int twl4030_get_gpio_datain(int gpio)
 
 static int twl_request(struct gpio_chip *chip, unsigned offset)
 {
+        struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
         int status = 0;
 
-        mutex_lock(&gpio_lock);
+        mutex_lock(&priv->mutex);
 
         /* Support the two LED outputs as output-only GPIOs. */
         if (offset >= TWL4030_GPIO_MAX) {
@@ -252,7 +249,7 @@ static int twl_request(struct gpio_chip *chip, unsigned offset)
         }
 
         /* on first use, turn GPIO module "on" */
-        if (!gpio_usage_count) {
+        if (!priv->usage_count) {
                 struct twl4030_gpio_platform_data *pdata;
                 u8 value = MASK_GPIO_CTRL_GPIO_ON;
 
@@ -266,79 +263,120 @@ static int twl_request(struct gpio_chip *chip, unsigned offset)
                 status = gpio_twl4030_write(REG_GPIO_CTRL, value);
         }
 
+done:
         if (!status)
-                gpio_usage_count |= (0x1 << offset);
+                priv->usage_count |= BIT(offset);
 
-done:
-        mutex_unlock(&gpio_lock);
+        mutex_unlock(&priv->mutex);
         return status;
 }
 
 static void twl_free(struct gpio_chip *chip, unsigned offset)
 {
+        struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
+
+        mutex_lock(&priv->mutex);
         if (offset >= TWL4030_GPIO_MAX) {
                 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, 1);
-                return;
+                goto out;
         }
 
-        mutex_lock(&gpio_lock);
-
-        gpio_usage_count &= ~BIT(offset);
+        priv->usage_count &= ~BIT(offset);
 
         /* on last use, switch off GPIO module */
-        if (!gpio_usage_count)
+        if (!priv->usage_count)
                 gpio_twl4030_write(REG_GPIO_CTRL, 0x0);
 
-        mutex_unlock(&gpio_lock);
+out:
+        mutex_unlock(&priv->mutex);
 }
 
 static int twl_direction_in(struct gpio_chip *chip, unsigned offset)
 {
-        return (offset < TWL4030_GPIO_MAX)
-                ? twl4030_set_gpio_direction(offset, 1)
-                : -EINVAL;
+        struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
+        int ret;
+
+        mutex_lock(&priv->mutex);
+        if (offset < TWL4030_GPIO_MAX)
+                ret = twl4030_set_gpio_direction(offset, 1);
+        else
+                ret = -EINVAL;
+
+        if (!ret)
+                priv->direction &= ~BIT(offset);
+
+        mutex_unlock(&priv->mutex);
+
+        return ret;
 }
 
 static int twl_get(struct gpio_chip *chip, unsigned offset)
 {
+        struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
+        int ret;
         int status = 0;
 
-        if (offset < TWL4030_GPIO_MAX)
-                status = twl4030_get_gpio_datain(offset);
-        else if (offset == TWL4030_GPIO_MAX)
-                status = cached_leden & LEDEN_LEDAON;
+        mutex_lock(&priv->mutex);
+        if (!(priv->usage_count & BIT(offset))) {
+                ret = -EPERM;
+                goto out;
+        }
+
+        if (priv->direction & BIT(offset))
+                status = priv->out_state & BIT(offset);
         else
-                status = cached_leden & LEDEN_LEDBON;
-        return (status < 0) ? 0 : status;
+                status = twl4030_get_gpio_datain(offset);
+
+        ret = (status <= 0) ? 0 : 1;
+out:
+        mutex_unlock(&priv->mutex);
+        return ret;
 }
 
-static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value)
+static void twl_set(struct gpio_chip *chip, unsigned offset, int value)
 {
-        if (offset < TWL4030_GPIO_MAX) {
+        struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
+
+        mutex_lock(&priv->mutex);
+        if (offset < TWL4030_GPIO_MAX)
                 twl4030_set_gpio_dataout(offset, value);
-                return twl4030_set_gpio_direction(offset, 0);
-        } else {
+        else
                 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value);
-                return 0;
-        }
+
+        if (value)
+                priv->out_state |= BIT(offset);
+        else
+                priv->out_state &= ~BIT(offset);
+
+        mutex_unlock(&priv->mutex);
 }
 
-static void twl_set(struct gpio_chip *chip, unsigned offset, int value)
+static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value)
 {
+        struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
+
+        mutex_lock(&priv->mutex);
         if (offset < TWL4030_GPIO_MAX)
                 twl4030_set_gpio_dataout(offset, value);
-        else
-                twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value);
+
+        priv->direction |= BIT(offset);
+        mutex_unlock(&priv->mutex);
+
+        twl_set(chip, offset, value);
+
+        return 0;
 }
 
 static int twl_to_irq(struct gpio_chip *chip, unsigned offset)
 {
-        return (twl4030_gpio_irq_base && (offset < TWL4030_GPIO_MAX))
-                ? (twl4030_gpio_irq_base + offset)
+        struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
+
+        return (priv->irq_base && (offset < TWL4030_GPIO_MAX))
+                ? (priv->irq_base + offset)
                 : -EINVAL;
 }
 
-static struct gpio_chip twl_gpiochip = {
+static struct gpio_chip template_chip = {
         .label                  = "twl4030",
         .owner                  = THIS_MODULE,
         .request                = twl_request,
@@ -424,8 +462,14 @@ static int gpio_twl4030_probe(struct platform_device *pdev)
 {
         struct twl4030_gpio_platform_data *pdata = pdev->dev.platform_data;
         struct device_node *node = pdev->dev.of_node;
+        struct gpio_twl4030_priv *priv;
         int ret, irq_base;
 
+        priv = devm_kzalloc(&pdev->dev, sizeof(struct gpio_twl4030_priv),
+                            GFP_KERNEL);
+        if (!priv)
+                return -ENOMEM;
+
         /* maybe setup IRQs */
         if (is_module()) {
                 dev_err(&pdev->dev, "can't dispatch IRQs from modules\n");
@@ -445,12 +489,15 @@ static int gpio_twl4030_probe(struct platform_device *pdev)
         if (ret < 0)
                 return ret;
 
-        twl4030_gpio_irq_base = irq_base;
+        priv->irq_base = irq_base;
 
 no_irqs:
-        twl_gpiochip.base = -1;
-        twl_gpiochip.ngpio = TWL4030_GPIO_MAX;
-        twl_gpiochip.dev = &pdev->dev;
+        priv->gpio_chip = template_chip;
+        priv->gpio_chip.base = -1;
+        priv->gpio_chip.ngpio = TWL4030_GPIO_MAX;
+        priv->gpio_chip.dev = &pdev->dev;
+
+        mutex_init(&priv->mutex);
 
         if (node)
                 pdata = of_gpio_twl4030(&pdev->dev);
@@ -481,23 +528,23 @@ no_irqs:
          * is (still) clear if use_leds is set.
          */
         if (pdata->use_leds)
-                twl_gpiochip.ngpio += 2;
+                priv->gpio_chip.ngpio += 2;
 
-        ret = gpiochip_add(&twl_gpiochip);
+        ret = gpiochip_add(&priv->gpio_chip);
         if (ret < 0) {
                 dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret);
-                twl_gpiochip.ngpio = 0;
+                priv->gpio_chip.ngpio = 0;
                 gpio_twl4030_remove(pdev);
                 goto out;
         }
 
-        twl4030_gpio_base = twl_gpiochip.base;
+        platform_set_drvdata(pdev, priv);
 
         if (pdata && pdata->setup) {
                 int status;
 
-                status = pdata->setup(&pdev->dev,
-                                twl4030_gpio_base, TWL4030_GPIO_MAX);
+                status = pdata->setup(&pdev->dev, priv->gpio_chip.base,
+                                      TWL4030_GPIO_MAX);
                 if (status)
                         dev_dbg(&pdev->dev, "setup --> %d\n", status);
         }
@@ -510,18 +557,19 @@ out:
 static int gpio_twl4030_remove(struct platform_device *pdev)
 {
         struct twl4030_gpio_platform_data *pdata = pdev->dev.platform_data;
+        struct gpio_twl4030_priv *priv = platform_get_drvdata(pdev);
         int status;
 
         if (pdata && pdata->teardown) {
-                status = pdata->teardown(&pdev->dev,
-                                twl4030_gpio_base, TWL4030_GPIO_MAX);
+                status = pdata->teardown(&pdev->dev, priv->gpio_chip.base,
+                                         TWL4030_GPIO_MAX);
                 if (status) {
                         dev_dbg(&pdev->dev, "teardown --> %d\n", status);
                         return status;
                 }
         }
 
-        status = gpiochip_remove(&twl_gpiochip);
+        status = gpiochip_remove(&priv->gpio_chip);
         if (status < 0)
                 return status;