ARM: davinci: gpio: use gpiolib API instead of inline functions
Remove NEED_MACH_GPIO_H config select option for ARCH_DAVINCI
to start using gpiolib interface for davinci platforms. This makes
it easier to use the gpio driver on other platforms as it breaks
dependency on mach-davinci.
Latencies for gpio_get/set APIs will increase. On measurement,
latency was found to have increased by 18 microsecond with
gpiolib API as compared to inline APIs.
Measurement was done on DA850 EVM for gpio_get_value() API by
taking the printk timing across the call with interrupts disabled.
inline gpio API with interrupt disabled
[ 29.734337] before gpio_get
[ 29.736847] after gpio_get
Time difference 0.00251
gpio library with interrupt disabled
[ 272.876763] before gpio_get
[ 272.879291] after gpio_get
Time difference 0.002528
Latency increased by (0.002528 - 0.00251) = 18 microsecond.
While at it, remove GPIO_TYPE_DAVINCI enum definition as
gpio-davinci.c is converted to Linux device driver model.
Signed-off-by: Philip Avinash <avinashphilip@ti.com>
Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
[nsekhar@ti.com: minor edits to commit message]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
diff --git a/include/linux/platform_data/gpio-davinci.h b/include/linux/platform_data/gpio-davinci.h
index 2fcc125..6efd202 100644
--- a/include/linux/platform_data/gpio-davinci.h
+++ b/include/linux/platform_data/gpio-davinci.h
@@ -16,10 +16,45 @@
#ifndef __DAVINCI_GPIO_PLATFORM_H
#define __DAVINCI_GPIO_PLATFORM_H
+#include <linux/io.h>
+#include <linux/spinlock.h>
+
+#include <asm-generic/gpio.h>
+
+enum davinci_gpio_type {
+ GPIO_TYPE_TNETV107X = 0,
+};
+
struct davinci_gpio_platform_data {
u32 ngpio;
u32 gpio_unbanked;
u32 intc_irq_num;
};
+
+struct davinci_gpio_controller {
+ struct gpio_chip chip;
+ int irq_base;
+ /* Serialize access to GPIO registers */
+ spinlock_t lock;
+ void __iomem *regs;
+ void __iomem *set_data;
+ void __iomem *clr_data;
+ void __iomem *in_data;
+ int gpio_unbanked;
+ unsigned gpio_irq;
+};
+
+/*
+ * basic gpio routines
+ */
+#define GPIO(X) (X) /* 0 <= X <= (DAVINCI_N_GPIO - 1) */
+
+/* Convert GPIO signal to GPIO pin number */
+#define GPIO_TO_PIN(bank, gpio) (16 * (bank) + (gpio))
+
+static inline u32 __gpio_mask(unsigned gpio)
+{
+ return 1 << (gpio % 32);
+}
#endif