gpiolib support for the PXA architecture

This adds gpiolib support for the PXA architecture:
  - move all GPIO API functions from generic.c into gpio.c
  - convert the gpio_get/set_value macros into inline functions

This makes it easier to hook up GPIOs provided by external chips like
ASICs and CPLDs.

Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Eric Miao <eric.miao@marvell.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Ben Gardner <bgardner@wabtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Minor ARM fixup from David Brownell folded into this ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 197 insertions, 0 deletions

diff --git a/arch/arm/mach-pxa/gpio.c b/arch/arm/mach-pxa/gpio.c
new file mode 100644
index 000000000000..8638dd7dd076
--- /dev/null
+++ b/arch/arm/mach-pxa/gpio.c
@@ -0,0 +1,197 @@
+/*
+ *  linux/arch/arm/mach-pxa/gpio.c
+ *
+ *  Generic PXA GPIO handling
+ *
+ *  Author:     Nicolas Pitre
+ *  Created:    Jun 15, 2001
+ *  Copyright:  MontaVista Software Inc.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+
+#include <asm/gpio.h>
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/arch/pxa-regs.h>
+
+#include "generic.h"
+
+
+struct pxa_gpio_chip {
+        struct gpio_chip chip;
+        void __iomem     *regbase;
+};
+
+int pxa_last_gpio;
+
+/*
+ * Configure pins for GPIO or other functions
+ */
+int pxa_gpio_mode(int gpio_mode)
+{
+        unsigned long flags;
+        int gpio = gpio_mode & GPIO_MD_MASK_NR;
+        int fn = (gpio_mode & GPIO_MD_MASK_FN) >> 8;
+        int gafr;
+
+        if (gpio > pxa_last_gpio)
+                return -EINVAL;
+
+        local_irq_save(flags);
+        if (gpio_mode & GPIO_DFLT_LOW)
+                GPCR(gpio) = GPIO_bit(gpio);
+        else if (gpio_mode & GPIO_DFLT_HIGH)
+                GPSR(gpio) = GPIO_bit(gpio);
+        if (gpio_mode & GPIO_MD_MASK_DIR)
+                GPDR(gpio) |= GPIO_bit(gpio);
+        else
+                GPDR(gpio) &= ~GPIO_bit(gpio);
+        gafr = GAFR(gpio) & ~(0x3 << (((gpio) & 0xf)*2));
+        GAFR(gpio) = gafr |  (fn  << (((gpio) & 0xf)*2));
+        local_irq_restore(flags);
+
+        return 0;
+}
+EXPORT_SYMBOL(pxa_gpio_mode);
+
+static int pxa_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+        unsigned long        flags;
+        u32                  mask = 1 << offset;
+        u32                  value;
+        struct pxa_gpio_chip *pxa;
+        void __iomem         *gpdr;
+
+        pxa = container_of(chip, struct pxa_gpio_chip, chip);
+        gpdr = pxa->regbase + GPDR_OFFSET;
+        local_irq_save(flags);
+        value = __raw_readl(gpdr);
+        value &= ~mask;
+        __raw_writel(value, gpdr);
+        local_irq_restore(flags);
+
+        return 0;
+}
+
+static int pxa_gpio_direction_output(struct gpio_chip *chip,
+                                        unsigned offset, int value)
+{
+        unsigned long        flags;
+        u32                  mask = 1 << offset;
+        u32                  tmp;
+        struct pxa_gpio_chip *pxa;
+        void __iomem         *gpdr;
+
+        pxa = container_of(chip, struct pxa_gpio_chip, chip);
+        __raw_writel(mask,
+                        pxa->regbase + (value ? GPSR_OFFSET : GPCR_OFFSET));
+        gpdr = pxa->regbase + GPDR_OFFSET;
+        local_irq_save(flags);
+        tmp = __raw_readl(gpdr);
+        tmp |= mask;
+        __raw_writel(tmp, gpdr);
+        local_irq_restore(flags);
+
+        return 0;
+}
+
+/*
+ * Return GPIO level
+ */
+static int pxa_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+        u32                  mask = 1 << offset;
+        struct pxa_gpio_chip *pxa;
+
+        pxa = container_of(chip, struct pxa_gpio_chip, chip);
+        return __raw_readl(pxa->regbase + GPLR_OFFSET) & mask;
+}
+
+/*
+ * Set output GPIO level
+ */
+static void pxa_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+        u32                  mask = 1 << offset;
+        struct pxa_gpio_chip *pxa;
+
+        pxa = container_of(chip, struct pxa_gpio_chip, chip);
+
+        if (value)
+                __raw_writel(mask, pxa->regbase + GPSR_OFFSET);
+        else
+                __raw_writel(mask, pxa->regbase + GPCR_OFFSET);
+}
+
+static struct pxa_gpio_chip pxa_gpio_chip[] = {
+        [0] = {
+                .regbase = GPIO0_BASE,
+                .chip = {
+                        .label            = "gpio-0",
+                        .direction_input  = pxa_gpio_direction_input,
+                        .direction_output = pxa_gpio_direction_output,
+                        .get              = pxa_gpio_get,
+                        .set              = pxa_gpio_set,
+                        .base             = 0,
+                        .ngpio            = 32,
+                },
+        },
+        [1] = {
+                .regbase = GPIO1_BASE,
+                .chip = {
+                        .label            = "gpio-1",
+                        .direction_input  = pxa_gpio_direction_input,
+                        .direction_output = pxa_gpio_direction_output,
+                        .get              = pxa_gpio_get,
+                        .set              = pxa_gpio_set,
+                        .base             = 32,
+                        .ngpio            = 32,
+                },
+        },
+        [2] = {
+                .regbase = GPIO2_BASE,
+                .chip = {
+                        .label            = "gpio-2",
+                        .direction_input  = pxa_gpio_direction_input,
+                        .direction_output = pxa_gpio_direction_output,
+                        .get              = pxa_gpio_get,
+                        .set              = pxa_gpio_set,
+                        .base             = 64,
+                        .ngpio            = 32, /* 21 for PXA25x */
+                },
+        },
+#if defined(CONFIG_PXA27x) || defined(CONFIG_PXA3xx)
+        [3] = {
+                .regbase = GPIO3_BASE,
+                .chip = {
+                        .label            = "gpio-3",
+                        .direction_input  = pxa_gpio_direction_input,
+                        .direction_output = pxa_gpio_direction_output,
+                        .get              = pxa_gpio_get,
+                        .set              = pxa_gpio_set,
+                        .base             = 96,
+                        .ngpio            = 32,
+                },
+        },
+#endif
+};
+
+void __init pxa_init_gpio(int gpio_nr)
+{
+        int i;
+
+        /* add a GPIO chip for each register bank.
+         * the last PXA25x register only contains 21 GPIOs
+         */
+        for (i = 0; i < gpio_nr; i += 32) {
+                if (i+32 > gpio_nr)
+                        pxa_gpio_chip[i/32].chip.ngpio = gpio_nr - i;
+                gpiochip_add(&pxa_gpio_chip[i/32].chip);
+        }
+}