[ARM] pxa: move common GPIO handling code into plat-pxa

1. add common GPIO handling code into [arch/arm/plat-pxa]

2. common code in <mach/gpio.h> moved into <plat/gpio.h>, new processors
   should implement its own <mach/gpio.h>, provide the following required
   definitions and '#include <plat/gpio.h>' in the end:

   - GPIO_REGS_VIRT for mapped virtual address of the GPIO registers'
     physical I/O memory

   - macros of GPLR(), GPSR(), GPDR() for constant optimization for
     functions gpio_{set,get}_value() (so that bit-bang code can still
     have tolerable performance)

   - NR_BUILTIN_GPIO for the number of onchip GPIO

   - definitions of __gpio_is_inverted() and __gpio_is_occupied(), they
     can be either macros or inlined functions

Signed-off-by: Eric Miao <eric.miao@marvell.com>

1 files changed, 62 insertions, 0 deletions

diff --git a/arch/arm/plat-pxa/include/plat/gpio.h b/arch/arm/plat-pxa/include/plat/gpio.h
new file mode 100644
index 0000000..44248cb
--- /dev/null
+++ b/arch/arm/plat-pxa/include/plat/gpio.h
@@ -0,0 +1,62 @@
+#ifndef __PLAT_GPIO_H
+#define __PLAT_GPIO_H
+
+/*
+ * We handle the GPIOs by banks, each bank covers up to 32 GPIOs with
+ * one set of registers. The register offsets are organized below:
+ *
+ *           GPLR    GPDR    GPSR    GPCR    GRER    GFER    GEDR
+ * BANK 0 - 0x0000  0x000C  0x0018  0x0024  0x0030  0x003C  0x0048
+ * BANK 1 - 0x0004  0x0010  0x001C  0x0028  0x0034  0x0040  0x004C
+ * BANK 2 - 0x0008  0x0014  0x0020  0x002C  0x0038  0x0044  0x0050
+ *
+ * BANK 3 - 0x0100  0x010C  0x0118  0x0124  0x0130  0x013C  0x0148
+ * BANK 4 - 0x0104  0x0110  0x011C  0x0128  0x0134  0x0140  0x014C
+ * BANK 5 - 0x0108  0x0114  0x0120  0x012C  0x0138  0x0144  0x0150
+ *
+ * NOTE:
+ *   BANK 3 is only available on PXA27x and later processors.
+ *   BANK 4 and 5 are only available on PXA935
+ */
+
+#define GPIO_BANK(n)	(GPIO_REGS_VIRT + BANK_OFF(n))
+
+#define GPLR_OFFSET	0x00
+#define GPDR_OFFSET	0x0C
+#define GPSR_OFFSET	0x18
+#define GPCR_OFFSET	0x24
+#define GRER_OFFSET	0x30
+#define GFER_OFFSET	0x3C
+#define GEDR_OFFSET	0x48
+
+static inline int gpio_get_value(unsigned gpio)
+{
+	if (__builtin_constant_p(gpio) && (gpio < NR_BUILTIN_GPIO))
+		return GPLR(gpio) & GPIO_bit(gpio);
+	else
+		return __gpio_get_value(gpio);
+}
+
+static inline void gpio_set_value(unsigned gpio, int value)
+{
+	if (__builtin_constant_p(gpio) && (gpio < NR_BUILTIN_GPIO)) {
+		if (value)
+			GPSR(gpio) = GPIO_bit(gpio);
+		else
+			GPCR(gpio) = GPIO_bit(gpio);
+	} else
+		__gpio_set_value(gpio, value);
+}
+
+#define gpio_cansleep		__gpio_cansleep
+
+/* NOTE: some PXAs have fewer on-chip GPIOs (like PXA255, with 85).
+ * Those cases currently cause holes in the GPIO number space, the
+ * actual number of the last GPIO is recorded by 'pxa_last_gpio'.
+ */
+extern int pxa_last_gpio;
+
+typedef int (*set_wake_t)(unsigned int irq, unsigned int on);
+
+extern void pxa_init_gpio(int mux_irq, int start, int end, set_wake_t fn);
+#endif /* __PLAT_GPIO_H */