summaryrefslogtreecommitdiff
path: root/arch/xtensa/variants/s6000/gpio.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/xtensa/variants/s6000/gpio.c')
-rw-r--r--arch/xtensa/variants/s6000/gpio.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/arch/xtensa/variants/s6000/gpio.c b/arch/xtensa/variants/s6000/gpio.c
new file mode 100644
index 000000000000..33a8d952934c
--- /dev/null
+++ b/arch/xtensa/variants/s6000/gpio.c
@@ -0,0 +1,71 @@
+/*
+ * s6000 gpio driver
+ *
+ * Copyright (c) 2009 emlix GmbH
+ * Authors: Oskar Schirmer <os@emlix.com>
+ * Johannes Weiner <jw@emlix.com>
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+
+#include <variant/hardware.h>
+
+#define S6_GPIO_DATA 0x000
+#define S6_GPIO_IS 0x404
+#define S6_GPIO_IBE 0x408
+#define S6_GPIO_IEV 0x40C
+#define S6_GPIO_IE 0x410
+#define S6_GPIO_RIS 0x414
+#define S6_GPIO_MIS 0x418
+#define S6_GPIO_IC 0x41C
+#define S6_GPIO_AFSEL 0x420
+#define S6_GPIO_DIR 0x800
+#define S6_GPIO_BANK(nr) ((nr) * 0x1000)
+#define S6_GPIO_MASK(nr) (4 << (nr))
+#define S6_GPIO_OFFSET(nr) \
+ (S6_GPIO_BANK((nr) >> 3) + S6_GPIO_MASK((nr) & 7))
+
+static int direction_input(struct gpio_chip *chip, unsigned int off)
+{
+ writeb(0, S6_REG_GPIO + S6_GPIO_DIR + S6_GPIO_OFFSET(off));
+ return 0;
+}
+
+static int get(struct gpio_chip *chip, unsigned int off)
+{
+ return readb(S6_REG_GPIO + S6_GPIO_DATA + S6_GPIO_OFFSET(off));
+}
+
+static int direction_output(struct gpio_chip *chip, unsigned int off, int val)
+{
+ unsigned rel = S6_GPIO_OFFSET(off);
+ writeb(~0, S6_REG_GPIO + S6_GPIO_DIR + rel);
+ writeb(val ? ~0 : 0, S6_REG_GPIO + S6_GPIO_DATA + rel);
+ return 0;
+}
+
+static void set(struct gpio_chip *chip, unsigned int off, int val)
+{
+ writeb(val ? ~0 : 0, S6_REG_GPIO + S6_GPIO_DATA + S6_GPIO_OFFSET(off));
+}
+
+static struct gpio_chip gpiochip = {
+ .owner = THIS_MODULE,
+ .direction_input = direction_input,
+ .get = get,
+ .direction_output = direction_output,
+ .set = set,
+ .base = 0,
+ .ngpio = 24,
+ .can_sleep = 0, /* no blocking io needed */
+ .exported = 0, /* no exporting to userspace */
+};
+
+static int gpio_init(void)
+{
+ return gpiochip_add(&gpiochip);
+}
+device_initcall(gpio_init);