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path: root/kernel/drivers/gpio/gpio-ks8695.c
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Diffstat (limited to 'kernel/drivers/gpio/gpio-ks8695.c')
-rw-r--r--kernel/drivers/gpio/gpio-ks8695.c317
1 files changed, 317 insertions, 0 deletions
diff --git a/kernel/drivers/gpio/gpio-ks8695.c b/kernel/drivers/gpio/gpio-ks8695.c
new file mode 100644
index 000000000..cc09b237e
--- /dev/null
+++ b/kernel/drivers/gpio/gpio-ks8695.c
@@ -0,0 +1,317 @@
+/*
+ * arch/arm/mach-ks8695/gpio.c
+ *
+ * Copyright (C) 2006 Andrew Victor
+ * Updated to GPIOLIB, Copyright 2008 Simtec Electronics
+ * Daniel Silverstone <dsilvers@simtec.co.uk>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include <linux/gpio.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/module.h>
+#include <linux/io.h>
+
+#include <mach/hardware.h>
+#include <asm/mach/irq.h>
+
+#include <mach/regs-gpio.h>
+#include <mach/gpio-ks8695.h>
+
+/*
+ * Configure a GPIO line for either GPIO function, or its internal
+ * function (Interrupt, Timer, etc).
+ */
+static void ks8695_gpio_mode(unsigned int pin, short gpio)
+{
+ unsigned int enable[] = { IOPC_IOEINT0EN, IOPC_IOEINT1EN, IOPC_IOEINT2EN, IOPC_IOEINT3EN, IOPC_IOTIM0EN, IOPC_IOTIM1EN };
+ unsigned long x, flags;
+
+ if (pin > KS8695_GPIO_5) /* only GPIO 0..5 have internal functions */
+ return;
+
+ local_irq_save(flags);
+
+ x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPC);
+ if (gpio) /* GPIO: set bit to 0 */
+ x &= ~enable[pin];
+ else /* Internal function: set bit to 1 */
+ x |= enable[pin];
+ __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPC);
+
+ local_irq_restore(flags);
+}
+
+
+static unsigned short gpio_irq[] = { KS8695_IRQ_EXTERN0, KS8695_IRQ_EXTERN1, KS8695_IRQ_EXTERN2, KS8695_IRQ_EXTERN3 };
+
+/*
+ * Configure GPIO pin as external interrupt source.
+ */
+int ks8695_gpio_interrupt(unsigned int pin, unsigned int type)
+{
+ unsigned long x, flags;
+
+ if (pin > KS8695_GPIO_3) /* only GPIO 0..3 can generate IRQ */
+ return -EINVAL;
+
+ local_irq_save(flags);
+
+ /* set pin as input */
+ x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM);
+ x &= ~IOPM(pin);
+ __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPM);
+
+ local_irq_restore(flags);
+
+ /* Set IRQ triggering type */
+ irq_set_irq_type(gpio_irq[pin], type);
+
+ /* enable interrupt mode */
+ ks8695_gpio_mode(pin, 0);
+
+ return 0;
+}
+EXPORT_SYMBOL(ks8695_gpio_interrupt);
+
+
+
+/* .... Generic GPIO interface .............................................. */
+
+/*
+ * Configure the GPIO line as an input.
+ */
+static int ks8695_gpio_direction_input(struct gpio_chip *gc, unsigned int pin)
+{
+ unsigned long x, flags;
+
+ if (pin > KS8695_GPIO_15)
+ return -EINVAL;
+
+ /* set pin to GPIO mode */
+ ks8695_gpio_mode(pin, 1);
+
+ local_irq_save(flags);
+
+ /* set pin as input */
+ x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM);
+ x &= ~IOPM(pin);
+ __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPM);
+
+ local_irq_restore(flags);
+
+ return 0;
+}
+
+
+/*
+ * Configure the GPIO line as an output, with default state.
+ */
+static int ks8695_gpio_direction_output(struct gpio_chip *gc,
+ unsigned int pin, int state)
+{
+ unsigned long x, flags;
+
+ if (pin > KS8695_GPIO_15)
+ return -EINVAL;
+
+ /* set pin to GPIO mode */
+ ks8695_gpio_mode(pin, 1);
+
+ local_irq_save(flags);
+
+ /* set line state */
+ x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD);
+ if (state)
+ x |= IOPD(pin);
+ else
+ x &= ~IOPD(pin);
+ __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPD);
+
+ /* set pin as output */
+ x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM);
+ x |= IOPM(pin);
+ __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPM);
+
+ local_irq_restore(flags);
+
+ return 0;
+}
+
+
+/*
+ * Set the state of an output GPIO line.
+ */
+static void ks8695_gpio_set_value(struct gpio_chip *gc,
+ unsigned int pin, int state)
+{
+ unsigned long x, flags;
+
+ if (pin > KS8695_GPIO_15)
+ return;
+
+ local_irq_save(flags);
+
+ /* set output line state */
+ x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD);
+ if (state)
+ x |= IOPD(pin);
+ else
+ x &= ~IOPD(pin);
+ __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPD);
+
+ local_irq_restore(flags);
+}
+
+
+/*
+ * Read the state of a GPIO line.
+ */
+static int ks8695_gpio_get_value(struct gpio_chip *gc, unsigned int pin)
+{
+ unsigned long x;
+
+ if (pin > KS8695_GPIO_15)
+ return -EINVAL;
+
+ x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD);
+ return (x & IOPD(pin)) != 0;
+}
+
+
+/*
+ * Map GPIO line to IRQ number.
+ */
+static int ks8695_gpio_to_irq(struct gpio_chip *gc, unsigned int pin)
+{
+ if (pin > KS8695_GPIO_3) /* only GPIO 0..3 can generate IRQ */
+ return -EINVAL;
+
+ return gpio_irq[pin];
+}
+
+/*
+ * Map IRQ number to GPIO line.
+ */
+int irq_to_gpio(unsigned int irq)
+{
+ if ((irq < KS8695_IRQ_EXTERN0) || (irq > KS8695_IRQ_EXTERN3))
+ return -EINVAL;
+
+ return (irq - KS8695_IRQ_EXTERN0);
+}
+EXPORT_SYMBOL(irq_to_gpio);
+
+/* GPIOLIB interface */
+
+static struct gpio_chip ks8695_gpio_chip = {
+ .label = "KS8695",
+ .direction_input = ks8695_gpio_direction_input,
+ .direction_output = ks8695_gpio_direction_output,
+ .get = ks8695_gpio_get_value,
+ .set = ks8695_gpio_set_value,
+ .to_irq = ks8695_gpio_to_irq,
+ .base = 0,
+ .ngpio = 16,
+ .can_sleep = false,
+};
+
+/* Register the GPIOs */
+void ks8695_register_gpios(void)
+{
+ if (gpiochip_add(&ks8695_gpio_chip))
+ printk(KERN_ERR "Unable to register core GPIOs\n");
+}
+
+/* .... Debug interface ..................................................... */
+
+#ifdef CONFIG_DEBUG_FS
+
+static int ks8695_gpio_show(struct seq_file *s, void *unused)
+{
+ unsigned int enable[] = { IOPC_IOEINT0EN, IOPC_IOEINT1EN, IOPC_IOEINT2EN, IOPC_IOEINT3EN, IOPC_IOTIM0EN, IOPC_IOTIM1EN };
+ unsigned int intmask[] = { IOPC_IOEINT0TM, IOPC_IOEINT1TM, IOPC_IOEINT2TM, IOPC_IOEINT3TM };
+ unsigned long mode, ctrl, data;
+ int i;
+
+ mode = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM);
+ ctrl = __raw_readl(KS8695_GPIO_VA + KS8695_IOPC);
+ data = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD);
+
+ seq_printf(s, "Pin\tI/O\tFunction\tState\n\n");
+
+ for (i = KS8695_GPIO_0; i <= KS8695_GPIO_15 ; i++) {
+ seq_printf(s, "%i:\t", i);
+
+ seq_printf(s, "%s\t", (mode & IOPM(i)) ? "Output" : "Input");
+
+ if (i <= KS8695_GPIO_3) {
+ if (ctrl & enable[i]) {
+ seq_printf(s, "EXT%i ", i);
+
+ switch ((ctrl & intmask[i]) >> (4 * i)) {
+ case IOPC_TM_LOW:
+ seq_printf(s, "(Low)"); break;
+ case IOPC_TM_HIGH:
+ seq_printf(s, "(High)"); break;
+ case IOPC_TM_RISING:
+ seq_printf(s, "(Rising)"); break;
+ case IOPC_TM_FALLING:
+ seq_printf(s, "(Falling)"); break;
+ case IOPC_TM_EDGE:
+ seq_printf(s, "(Edges)"); break;
+ }
+ } else
+ seq_printf(s, "GPIO\t");
+ } else if (i <= KS8695_GPIO_5) {
+ if (ctrl & enable[i])
+ seq_printf(s, "TOUT%i\t", i - KS8695_GPIO_4);
+ else
+ seq_printf(s, "GPIO\t");
+ } else {
+ seq_printf(s, "GPIO\t");
+ }
+
+ seq_printf(s, "\t");
+
+ seq_printf(s, "%i\n", (data & IOPD(i)) ? 1 : 0);
+ }
+ return 0;
+}
+
+static int ks8695_gpio_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, ks8695_gpio_show, NULL);
+}
+
+static const struct file_operations ks8695_gpio_operations = {
+ .open = ks8695_gpio_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int __init ks8695_gpio_debugfs_init(void)
+{
+ /* /sys/kernel/debug/ks8695_gpio */
+ (void) debugfs_create_file("ks8695_gpio", S_IFREG | S_IRUGO, NULL, NULL, &ks8695_gpio_operations);
+ return 0;
+}
+postcore_initcall(ks8695_gpio_debugfs_init);
+
+#endif