ARM: OMAP: Use gpiolib

Update OMAP to use the new GPIO implementation framework.  This is just a
quick'n'dirty update ... more code could now be removed, ideally as part
of cleaning up the entire OMAP GPIO infrastructure ...

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>

3 files changed, 105 insertions, 60 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 4039a133006e..992028f46bd1 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -468,6 +468,7 @@ config ARCH_DAVINCI
 config ARCH_OMAP
         bool "TI OMAP"
         select GENERIC_GPIO
+        select HAVE_GPIO_LIB
         select GENERIC_TIME
         select GENERIC_CLOCKEVENTS
         help
diff --git a/arch/arm/plat-omap/gpio.c b/arch/arm/plat-omap/gpio.c
index 8c78e4e57b5c..56889fdb0740 100644
--- a/arch/arm/plat-omap/gpio.c
+++ b/arch/arm/plat-omap/gpio.c
@@ -136,7 +136,6 @@ struct gpio_bank {
         u16 irq;
         u16 virtual_irq_start;
         int method;
-        u32 reserved_map;
 #if defined(CONFIG_ARCH_OMAP16XX) || defined(CONFIG_ARCH_OMAP24XX) || defined(CONFIG_ARCH_OMAP34XX)
         u32 suspend_wakeup;
         u32 saved_wakeup;
@@ -150,6 +149,7 @@ struct gpio_bank {
         u32 saved_risingdetect;
 #endif
         spinlock_t lock;
+        struct gpio_chip chip;
 };
 
 #define METHOD_MPUIO            0
@@ -903,19 +903,17 @@ int omap_request_gpio(int gpio)
 {
         struct gpio_bank *bank;
         unsigned long flags;
+        int status;
 
         if (check_gpio(gpio) < 0)
                 return -EINVAL;
 
+        status = gpio_request(gpio, NULL);
+        if (status < 0)
+                return status;
+
         bank = get_gpio_bank(gpio);
         spin_lock_irqsave(&bank->lock, flags);
-        if (unlikely(bank->reserved_map & (1 << get_gpio_index(gpio)))) {
-                printk(KERN_ERR "omap-gpio: GPIO %d is already reserved!\n", gpio);
-                dump_stack();
-                spin_unlock_irqrestore(&bank->lock, flags);
-                return -1;
-        }
-        bank->reserved_map |= (1 << get_gpio_index(gpio));
 
         /* Set trigger to none. You need to enable the desired trigger with
          * request_irq() or set_irq_type().
@@ -945,10 +943,11 @@ void omap_free_gpio(int gpio)
                 return;
         bank = get_gpio_bank(gpio);
         spin_lock_irqsave(&bank->lock, flags);
-        if (unlikely(!(bank->reserved_map & (1 << get_gpio_index(gpio))))) {
+        if (unlikely(!gpiochip_is_requested(&bank->chip,
+                                get_gpio_index(gpio)))) {
+                spin_unlock_irqrestore(&bank->lock, flags);
                 printk(KERN_ERR "omap-gpio: GPIO %d wasn't reserved!\n", gpio);
                 dump_stack();
-                spin_unlock_irqrestore(&bank->lock, flags);
                 return;
         }
 #ifdef CONFIG_ARCH_OMAP16XX
@@ -965,9 +964,9 @@ void omap_free_gpio(int gpio)
                 __raw_writel(1 << get_gpio_index(gpio), reg);
         }
 #endif
-        bank->reserved_map &= ~(1 << get_gpio_index(gpio));
         _reset_gpio(bank, gpio);
         spin_unlock_irqrestore(&bank->lock, flags);
+        gpio_free(gpio);
 }
 
 /*
@@ -1266,6 +1265,53 @@ static inline void mpuio_init(void) {}
 
 /*---------------------------------------------------------------------*/
 
+/* REVISIT these are stupid implementations!  replace by ones that
+ * don't switch on METHOD_* and which mostly avoid spinlocks
+ */
+
+static int gpio_input(struct gpio_chip *chip, unsigned offset)
+{
+        struct gpio_bank *bank;
+        unsigned long flags;
+
+        bank = container_of(chip, struct gpio_bank, chip);
+        spin_lock_irqsave(&bank->lock, flags);
+        _set_gpio_direction(bank, offset, 1);
+        spin_unlock_irqrestore(&bank->lock, flags);
+        return 0;
+}
+
+static int gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+        return omap_get_gpio_datain(chip->base + offset);
+}
+
+static int gpio_output(struct gpio_chip *chip, unsigned offset, int value)
+{
+        struct gpio_bank *bank;
+        unsigned long flags;
+
+        bank = container_of(chip, struct gpio_bank, chip);
+        spin_lock_irqsave(&bank->lock, flags);
+        _set_gpio_dataout(bank, offset, value);
+        _set_gpio_direction(bank, offset, 0);
+        spin_unlock_irqrestore(&bank->lock, flags);
+        return 0;
+}
+
+static void gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+        struct gpio_bank *bank;
+        unsigned long flags;
+
+        bank = container_of(chip, struct gpio_bank, chip);
+        spin_lock_irqsave(&bank->lock, flags);
+        _set_gpio_dataout(bank, offset, value);
+        spin_unlock_irqrestore(&bank->lock, flags);
+}
+
+/*---------------------------------------------------------------------*/
+
 static int initialized;
 #if !defined(CONFIG_ARCH_OMAP3)
 static struct clk * gpio_ick;
@@ -1293,6 +1339,7 @@ static struct lock_class_key gpio_lock_class;
 static int __init _omap_gpio_init(void)
 {
         int i;
+        int gpio = 0;
         struct gpio_bank *bank;
 #if defined(CONFIG_ARCH_OMAP3)
         char clk_name[11];
@@ -1423,7 +1470,6 @@ static int __init _omap_gpio_init(void)
                 int j, gpio_count = 16;
 
                 bank = &gpio_bank[i];
-                bank->reserved_map = 0;
                 bank->base = IO_ADDRESS(bank->base);
                 spin_lock_init(&bank->lock);
                 if (bank_is_mpuio(bank))
@@ -1461,6 +1507,26 @@ static int __init _omap_gpio_init(void)
                         gpio_count = 32;
                 }
 #endif
+
+                /* REVISIT eventually switch from OMAP-specific gpio structs
+                 * over to the generic ones
+                 */
+                bank->chip.direction_input = gpio_input;
+                bank->chip.get = gpio_get;
+                bank->chip.direction_output = gpio_output;
+                bank->chip.set = gpio_set;
+                if (bank_is_mpuio(bank)) {
+                        bank->chip.label = "mpuio";
+                        bank->chip.base = OMAP_MPUIO(0);
+                } else {
+                        bank->chip.label = "gpio";
+                        bank->chip.base = gpio;
+                        gpio += gpio_count;
+                }
+                bank->chip.ngpio = gpio_count;
+
+                gpiochip_add(&bank->chip);
+
                 for (j = bank->virtual_irq_start;
                      j < bank->virtual_irq_start + gpio_count; j++) {
                         lockdep_set_class(&irq_desc[j].lock, &gpio_lock_class);
@@ -1757,8 +1823,10 @@ static int dbg_gpio_show(struct seq_file *s, void *unused)
 
                 for (j = 0; j < bankwidth; j++, gpio++, mask <<= 1) {
                         unsigned        irq, value, is_in, irqstat;
+                        const char      *label;
 
-                        if (!(bank->reserved_map & mask))
+                        label = gpiochip_is_requested(&bank->chip, j);
+                        if (!label)
                                 continue;
 
                         irq = bank->virtual_irq_start + j;
@@ -1766,13 +1834,16 @@ static int dbg_gpio_show(struct seq_file *s, void *unused)
                         is_in = gpio_is_input(bank, mask);
 
                         if (bank_is_mpuio(bank))
-                                seq_printf(s, "MPUIO %2d: ", j);
+                                seq_printf(s, "MPUIO %2d ", j);
                         else
-                                seq_printf(s, "GPIO %3d: ", gpio);
-                        seq_printf(s, "%s %s",
+                                seq_printf(s, "GPIO %3d ", gpio);
+                        seq_printf(s, "(%10s): %s %s",
+                                        label,
                                         is_in ? "in " : "out",
                                         value ? "hi"  : "lo");
 
+/* FIXME for at least omap2, show pullup/pulldown state */
+
                         irqstat = irq_desc[irq].status;
                         if (is_in && ((bank->suspend_wakeup & mask)
                                         || irqstat & IRQ_TYPE_SENSE_MASK)) {
@@ -1795,10 +1866,10 @@ static int dbg_gpio_show(struct seq_file *s, void *unused)
                                         trigger = "high";
                                         break;
                                 case IRQ_TYPE_NONE:
-                                        trigger = "(unspecified)";
+                                        trigger = "(?)";
                                         break;
                                 }
-                                seq_printf(s, ", irq-%d %s%s",
+                                seq_printf(s, ", irq-%d %-8s%s",
                                                 irq, trigger,
                                                 (bank->suspend_wakeup & mask)
                                                         ? " wakeup" : "");
diff --git a/include/asm-arm/arch-omap/gpio.h b/include/asm-arm/arch-omap/gpio.h
index 164da09be095..86621a04cd8f 100644
--- a/include/asm-arm/arch-omap/gpio.h
+++ b/include/asm-arm/arch-omap/gpio.h
@@ -82,62 +82,35 @@ extern void omap_set_gpio_debounce_time(int gpio, int enable);
 
 /*-------------------------------------------------------------------------*/
 
-/* wrappers for "new style" GPIO calls. the old OMAP-specfic ones should
- * eventually be removed (along with this errno.h inclusion), and maybe
- * gpios should put MPUIOs last too.
+/* Wrappers for "new style" GPIO calls, using the new infrastructure
+ * which lets us plug in FPGA, I2C, and other implementations.
+ * *
+ * The original OMAP-specfic calls should eventually be removed.
  */
 
-#include <asm/errno.h>
-
-static inline int gpio_request(unsigned gpio, const char *label)
-{
-        return omap_request_gpio(gpio);
-}
-
-static inline void gpio_free(unsigned gpio)
-{
-        omap_free_gpio(gpio);
-}
-
-static inline int __gpio_set_direction(unsigned gpio, int is_input)
-{
-        if (cpu_class_is_omap2()) {
-                if (gpio > OMAP_MAX_GPIO_LINES)
-                        return -EINVAL;
-        } else {
-                if (gpio > (OMAP_MAX_GPIO_LINES + 16 /* MPUIO */))
-                        return -EINVAL;
-        }
-        omap_set_gpio_direction(gpio, is_input);
-        return 0;
-}
-
-static inline int gpio_direction_input(unsigned gpio)
-{
-        return __gpio_set_direction(gpio, 1);
-}
-
-static inline int gpio_direction_output(unsigned gpio, int value)
-{
-        omap_set_gpio_dataout(gpio, value);
-        return __gpio_set_direction(gpio, 0);
-}
+#include <linux/errno.h>
+#include <asm-generic/gpio.h>
 
 static inline int gpio_get_value(unsigned gpio)
 {
-        return omap_get_gpio_datain(gpio);
+        return __gpio_get_value(gpio);
 }
 
 static inline void gpio_set_value(unsigned gpio, int value)
 {
-        omap_set_gpio_dataout(gpio, value);
+        __gpio_set_value(gpio, value);
 }
 
-#include <asm-generic/gpio.h>           /* cansleep wrappers */
+static inline int gpio_cansleep(unsigned gpio)
+{
+        return __gpio_cansleep(gpio);
+}
 
 static inline int gpio_to_irq(unsigned gpio)
 {
-        return OMAP_GPIO_IRQ(gpio);
+        if (gpio < (OMAP_MAX_GPIO_LINES + 16))
+                return OMAP_GPIO_IRQ(gpio);
+        return -EINVAL;
 }
 
 static inline int irq_to_gpio(unsigned irq)