Davinci: tnetv107x initial gpio support

This patch adds support for the tnetv107x gpio controller.

Key differences between davinci and tnetv107x controllers:
 - register map - davinci's controller is organized into banks of 32 gpios,
   tnetv107x has a single space with arrays of registers for in, out,
   direction, etc.
 - davinci's controller has separate set/clear registers for output, tnetv107x
   has a single direct mapped register.

This patch does not yet add gpio irq support on this controller.

Signed-off-by: Cyril Chemparathy <cyril@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

1 files changed, 15 insertions, 7 deletions

diff --git a/arch/arm/mach-davinci/include/mach/gpio.h b/arch/arm/mach-davinci/include/mach/gpio.h
index 504cc180a60b..fbece126c2bf 100644
--- a/arch/arm/mach-davinci/include/mach/gpio.h
+++ b/arch/arm/mach-davinci/include/mach/gpio.h
@@ -25,6 +25,7 @@
 
 enum davinci_gpio_type {
         GPIO_TYPE_DAVINCI = 0,
+        GPIO_TYPE_TNETV107X,
 };
 
 /*
@@ -87,9 +88,13 @@ static inline u32 __gpio_mask(unsigned gpio)
         return 1 << (gpio % 32);
 }
 
-/* The get/set/clear functions will inline when called with constant
+/*
+ * The get/set/clear functions will inline when called with constant
  * parameters referencing built-in GPIOs, for low-overhead bitbanging.
  *
+ * gpio_set_value() will inline only on traditional Davinci style controllers
+ * with distinct set/clear registers.
+ *
  * Otherwise, calls with variable parameters or referencing external
  * GPIOs (e.g. on GPIO expander chips) use outlined functions.
  */
@@ -100,12 +105,15 @@ static inline void gpio_set_value(unsigned gpio, int value)
                 u32                             mask;
 
                 ctlr = __gpio_to_controller(gpio);
-                mask = __gpio_mask(gpio);
-                if (value)
-                        __raw_writel(mask, ctlr->set_data);
-                else
-                        __raw_writel(mask, ctlr->clr_data);
-                return;
+
+                if (ctlr->set_data != ctlr->clr_data) {
+                        mask = __gpio_mask(gpio);
+                        if (value)
+                                __raw_writel(mask, ctlr->set_data);
+                        else
+                                __raw_writel(mask, ctlr->clr_data);
+                        return;
+                }
         }
 
         __gpio_set_value(gpio, value);