xtensa: s6000 variant

Support for the Stretch S6000 Xtensa core variant.

Signed-off-by: Johannes Weiner <jw@emlix.com>
Signed-off-by: Oskar Schirmer <os@emlix.com>
Signed-off-by: Chris Zankel <chris@zankel.net>

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);