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Diffstat (limited to 'arch/mips/rb532/gpio.c')
-rw-r--r--arch/mips/rb532/gpio.c201
1 files changed, 201 insertions, 0 deletions
diff --git a/arch/mips/rb532/gpio.c b/arch/mips/rb532/gpio.c
new file mode 100644
index 000000000..5aa3df853
--- /dev/null
+++ b/arch/mips/rb532/gpio.c
@@ -0,0 +1,201 @@
+/*
+ * Miscellaneous functions for IDT EB434 board
+ *
+ * Copyright 2004 IDT Inc. (rischelp@idt.com)
+ * Copyright 2006 Phil Sutter <n0-1@freewrt.org>
+ * Copyright 2007 Florian Fainelli <florian@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
+ * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/export.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+
+#include <asm/mach-rc32434/rb.h>
+#include <asm/mach-rc32434/gpio.h>
+
+struct rb532_gpio_chip {
+ struct gpio_chip chip;
+ void __iomem *regbase;
+};
+
+static struct resource rb532_gpio_reg0_res[] = {
+ {
+ .name = "gpio_reg0",
+ .start = REGBASE + GPIOBASE,
+ .end = REGBASE + GPIOBASE + sizeof(struct rb532_gpio_reg) - 1,
+ .flags = IORESOURCE_MEM,
+ }
+};
+
+/* rb532_set_bit - sanely set a bit
+ *
+ * bitval: new value for the bit
+ * offset: bit index in the 4 byte address range
+ * ioaddr: 4 byte aligned address being altered
+ */
+static inline void rb532_set_bit(unsigned bitval,
+ unsigned offset, void __iomem *ioaddr)
+{
+ unsigned long flags;
+ u32 val;
+
+ local_irq_save(flags);
+
+ val = readl(ioaddr);
+ val &= ~(!bitval << offset); /* unset bit if bitval == 0 */
+ val |= (!!bitval << offset); /* set bit if bitval == 1 */
+ writel(val, ioaddr);
+
+ local_irq_restore(flags);
+}
+
+/* rb532_get_bit - read a bit
+ *
+ * returns the boolean state of the bit, which may be > 1
+ */
+static inline int rb532_get_bit(unsigned offset, void __iomem *ioaddr)
+{
+ return readl(ioaddr) & (1 << offset);
+}
+
+/*
+ * Return GPIO level */
+static int rb532_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct rb532_gpio_chip *gpch;
+
+ gpch = container_of(chip, struct rb532_gpio_chip, chip);
+ return rb532_get_bit(offset, gpch->regbase + GPIOD);
+}
+
+/*
+ * Set output GPIO level
+ */
+static void rb532_gpio_set(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ struct rb532_gpio_chip *gpch;
+
+ gpch = container_of(chip, struct rb532_gpio_chip, chip);
+ rb532_set_bit(value, offset, gpch->regbase + GPIOD);
+}
+
+/*
+ * Set GPIO direction to input
+ */
+static int rb532_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+ struct rb532_gpio_chip *gpch;
+
+ gpch = container_of(chip, struct rb532_gpio_chip, chip);
+
+ /* disable alternate function in case it's set */
+ rb532_set_bit(0, offset, gpch->regbase + GPIOFUNC);
+
+ rb532_set_bit(0, offset, gpch->regbase + GPIOCFG);
+ return 0;
+}
+
+/*
+ * Set GPIO direction to output
+ */
+static int rb532_gpio_direction_output(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ struct rb532_gpio_chip *gpch;
+
+ gpch = container_of(chip, struct rb532_gpio_chip, chip);
+
+ /* disable alternate function in case it's set */
+ rb532_set_bit(0, offset, gpch->regbase + GPIOFUNC);
+
+ /* set the initial output value */
+ rb532_set_bit(value, offset, gpch->regbase + GPIOD);
+
+ rb532_set_bit(1, offset, gpch->regbase + GPIOCFG);
+ return 0;
+}
+
+static struct rb532_gpio_chip rb532_gpio_chip[] = {
+ [0] = {
+ .chip = {
+ .label = "gpio0",
+ .direction_input = rb532_gpio_direction_input,
+ .direction_output = rb532_gpio_direction_output,
+ .get = rb532_gpio_get,
+ .set = rb532_gpio_set,
+ .base = 0,
+ .ngpio = 32,
+ },
+ },
+};
+
+/*
+ * Set GPIO interrupt level
+ */
+void rb532_gpio_set_ilevel(int bit, unsigned gpio)
+{
+ rb532_set_bit(bit, gpio, rb532_gpio_chip->regbase + GPIOILEVEL);
+}
+EXPORT_SYMBOL(rb532_gpio_set_ilevel);
+
+/*
+ * Set GPIO interrupt status
+ */
+void rb532_gpio_set_istat(int bit, unsigned gpio)
+{
+ rb532_set_bit(bit, gpio, rb532_gpio_chip->regbase + GPIOISTAT);
+}
+EXPORT_SYMBOL(rb532_gpio_set_istat);
+
+/*
+ * Configure GPIO alternate function
+ */
+void rb532_gpio_set_func(unsigned gpio)
+{
+ rb532_set_bit(1, gpio, rb532_gpio_chip->regbase + GPIOFUNC);
+}
+EXPORT_SYMBOL(rb532_gpio_set_func);
+
+int __init rb532_gpio_init(void)
+{
+ struct resource *r;
+
+ r = rb532_gpio_reg0_res;
+ rb532_gpio_chip->regbase = ioremap_nocache(r->start, resource_size(r));
+
+ if (!rb532_gpio_chip->regbase) {
+ printk(KERN_ERR "rb532: cannot remap GPIO register 0\n");
+ return -ENXIO;
+ }
+
+ /* Register our GPIO chip */
+ gpiochip_add(&rb532_gpio_chip->chip);
+
+ return 0;
+}
+arch_initcall(rb532_gpio_init);