ARM: Merge for-2635/gpio2

Merge branch 'for-2635/gpio2' into for-linus/samsung2

3 files changed, 86 insertions, 0 deletions

diff --git a/arch/arm/plat-samsung/include/plat/gpio-cfg-helpers.h b/arch/arm/plat-samsung/include/plat/gpio-cfg-helpers.h
index dda19da037ad..3e21c75feefa 100644
--- a/arch/arm/plat-samsung/include/plat/gpio-cfg-helpers.h
+++ b/arch/arm/plat-samsung/include/plat/gpio-cfg-helpers.h
@@ -30,6 +30,12 @@ static inline int s3c_gpio_do_setcfg(struct s3c_gpio_chip *chip,
 	return (chip->config->set_config)(chip, off, config);
 }
 
+static inline unsigned s3c_gpio_do_getcfg(struct s3c_gpio_chip *chip,
+					  unsigned int off)
+{
+	return (chip->config->get_config)(chip, off);
+}
+
 static inline int s3c_gpio_do_setpull(struct s3c_gpio_chip *chip,
 				      unsigned int off, s3c_gpio_pull_t pull)
 {
@@ -53,6 +59,18 @@ extern int s3c_gpio_setcfg_s3c24xx(struct s3c_gpio_chip *chip,
 				   unsigned int off, unsigned int cfg);
 
 /**
+ * s3c_gpio_getcfg_s3c24xx - S3C24XX style GPIO configuration read.
+ * @chip: The gpio chip that is being configured.
+ * @off: The offset for the GPIO being configured.
+ *
+ * The reverse of s3c_gpio_setcfg_s3c24xx(). Will return a value whicg
+ * could be directly passed back to s3c_gpio_setcfg_s3c24xx(), from the
+ * S3C_GPIO_SPECIAL() macro.
+ */
+unsigned int s3c_gpio_getcfg_s3c24xx(struct s3c_gpio_chip *chip,
+				     unsigned int off);
+
+/**
  * s3c_gpio_setcfg_s3c24xx_a - S3C24XX style GPIO configuration (Bank A)
  * @chip: The gpio chip that is being configured.
  * @off: The offset for the GPIO being configured.
@@ -65,6 +83,21 @@ extern int s3c_gpio_setcfg_s3c24xx(struct s3c_gpio_chip *chip,
 extern int s3c_gpio_setcfg_s3c24xx_a(struct s3c_gpio_chip *chip,
 				     unsigned int off, unsigned int cfg);
 
+
+/**
+ * s3c_gpio_getcfg_s3c24xx_a - S3C24XX style GPIO configuration read (Bank A)
+ * @chip: The gpio chip that is being configured.
+ * @off: The offset for the GPIO being configured.
+ *
+ * The reverse of s3c_gpio_setcfg_s3c24xx_a() turning an GPIO into a usable
+ * GPIO configuration value.
+ *
+ * @sa s3c_gpio_getcfg_s3c24xx
+ * @sa s3c_gpio_getcfg_s3c64xx_4bit
+ */
+extern unsigned s3c_gpio_getcfg_s3c24xx_a(struct s3c_gpio_chip *chip,
+					  unsigned int off);
+
 /**
  * s3c_gpio_setcfg_s3c64xx_4bit - S3C64XX 4bit single register GPIO config.
  * @chip: The gpio chip that is being configured.
@@ -85,6 +118,20 @@ extern int s3c_gpio_setcfg_s3c64xx_4bit(struct s3c_gpio_chip *chip,
 					unsigned int off, unsigned int cfg);
 
 
+/**
+ * s3c_gpio_getcfg_s3c64xx_4bit - S3C64XX 4bit single register GPIO config read.
+ * @chip: The gpio chip that is being configured.
+ * @off: The offset for the GPIO being configured.
+ *
+ * The reverse of s3c_gpio_setcfg_s3c64xx_4bit(), turning a gpio configuration
+ * register setting into a value the software can use, such as could be passed
+ * to s3c_gpio_setcfg_s3c64xx_4bit().
+ *
+ * @sa s3c_gpio_getcfg_s3c24xx
+ */
+extern unsigned s3c_gpio_getcfg_s3c64xx_4bit(struct s3c_gpio_chip *chip,
+					     unsigned int off);
+
 /* Pull-{up,down} resistor controls.
  *
  * S3C2410,S3C2440,S3C24A0 = Pull-UP,
@@ -146,6 +193,17 @@ extern s3c_gpio_pull_t s3c_gpio_getpull_updown(struct s3c_gpio_chip *chip,
 					       unsigned int off);
 
 /**
+ * s3c_gpio_getpull_1up() - Get configuration for choice of up or none
+ * @chip: The gpio chip that the GPIO pin belongs to
+ * @off: The offset to the pin to get the configuration of.
+ *
+ * This helper function reads the state of the pull-up resistor for the
+ * given GPIO in the same case as s3c_gpio_setpull_1up.
+*/
+extern s3c_gpio_pull_t s3c_gpio_getpull_1up(struct s3c_gpio_chip *chip,
+					    unsigned int off);
+
+/**
  * s3c_gpio_setpull_s3c2443() - Pull configuration for s3c2443.
  * @chip: The gpio chip that is being configured.
  * @off: The offset for the GPIO being configured.
diff --git a/arch/arm/plat-samsung/include/plat/gpio-cfg.h b/arch/arm/plat-samsung/include/plat/gpio-cfg.h
index 29cd6a86cade..8d01e853df39 100644
--- a/arch/arm/plat-samsung/include/plat/gpio-cfg.h
+++ b/arch/arm/plat-samsung/include/plat/gpio-cfg.h
@@ -77,6 +77,17 @@ struct s3c_gpio_cfg {
  */
 extern int s3c_gpio_cfgpin(unsigned int pin, unsigned int to);
 
+/**
+ * s3c_gpio_getcfg - Read the current function for a GPIO pin
+ * @pin: The pin to read the configuration value for.
+ *
+ * Read the configuration state of the given @pin, returning a value that
+ * could be passed back to s3c_gpio_cfgpin().
+ *
+ * @sa s3c_gpio_cfgpin
+ */
+extern unsigned s3c_gpio_getcfg(unsigned int pin);
+
 /* Define values for the pull-{up,down} available for each gpio pin.
  *
  * These values control the state of the weak pull-{up,down} resistors
diff --git a/arch/arm/plat-samsung/include/plat/gpio-core.h b/arch/arm/plat-samsung/include/plat/gpio-core.h
index 49ff406a7066..f3a68d1a07b9 100644
--- a/arch/arm/plat-samsung/include/plat/gpio-core.h
+++ b/arch/arm/plat-samsung/include/plat/gpio-core.h
@@ -44,16 +44,26 @@ struct s3c_gpio_cfg;
  * @chip: The chip structure to be exported via gpiolib.
  * @base: The base pointer to the gpio configuration registers.
  * @config: special function and pull-resistor control information.
+ * @lock: Lock for exclusive access to this gpio bank.
  * @pm_save: Save information for suspend/resume support.
  *
  * This wrapper provides the necessary information for the Samsung
  * specific gpios being registered with gpiolib.
+ *
+ * The lock protects each gpio bank from multiple access of the shared
+ * configuration registers, or from reading of data whilst another thread
+ * is writing to the register set.
+ *
+ * Each chip has its own lock to avoid any  contention between different
+ * CPU cores trying to get one lock for different GPIO banks, where each
+ * bank of GPIO has its own register space and configuration registers.
  */
 struct s3c_gpio_chip {
 	struct gpio_chip	chip;
 	struct s3c_gpio_cfg	*config;
 	struct s3c_gpio_pm	*pm;
 	void __iomem		*base;
+	spinlock_t		 lock;
 #ifdef CONFIG_PM
 	u32			pm_save[4];
 #endif
@@ -108,6 +118,9 @@ extern void samsung_gpiolib_add_4bit2_chips(struct s3c_gpio_chip *chip,
 extern void samsung_gpiolib_add_4bit(struct s3c_gpio_chip *chip);
 extern void samsung_gpiolib_add_4bit2(struct s3c_gpio_chip *chip);
 
+/* exported for core SoC support to change */
+extern struct s3c_gpio_cfg s3c24xx_gpiocfg_default;
+
 #ifdef CONFIG_S3C_GPIO_TRACK
 extern struct s3c_gpio_chip *s3c_gpios[S3C_GPIO_END];
 
@@ -135,3 +148,7 @@ extern struct s3c_gpio_pm s3c_gpio_pm_4bit;
 #define __gpio_pm(x) NULL
 
 #endif /* CONFIG_PM */
+
+/* locking wrappers to deal with multiple access to the same gpio bank */
+#define s3c_gpio_lock(_oc, _fl) spin_lock_irqsave(&(_oc)->lock, _fl)
+#define s3c_gpio_unlock(_oc, _fl) spin_unlock_irqrestore(&(_oc)->lock, _fl)