ARM: 6597/1: Add basic architecture support for VIA/WonderMedia 85xx SoC's

This adds support for the family of Systems-on-Chip produced initially
by VIA and now its subsidiary WonderMedia that have recently become
widespread in lower-end Chinese ARM-based tablets and netbooks.

Support is included for both VT8500 and WM8505, selectable by a
configuration switch at kernel build time.

Included are basic machine initialization files, register and
interrupt definitions, support for the on-chip interrupt controller,
high-precision OS timer, GPIO lines, necessary macros for early debug,
pulse-width-modulated outputs control, as well as platform device
configurations for the specific drivers implemented elsewhere.

Signed-off-by: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 240 insertions, 0 deletions

diff --git a/arch/arm/mach-vt8500/gpio.c b/arch/arm/mach-vt8500/gpio.c
new file mode 100644
index 000000000000..2bcc0ec783df
--- /dev/null
+++ b/arch/arm/mach-vt8500/gpio.c
@@ -0,0 +1,240 @@
+/* linux/arch/arm/mach-vt8500/gpio.c
+ *
+ * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+
+#include <linux/gpio.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+
+#include "devices.h"
+
+#define to_vt8500(__chip) container_of(__chip, struct vt8500_gpio_chip, chip)
+
+#define ENABLE_REGS	0x0
+#define DIRECTION_REGS	0x20
+#define OUTVALUE_REGS	0x40
+#define INVALUE_REGS	0x60
+
+#define EXT_REGOFF	0x1c
+
+static void __iomem *regbase;
+
+struct vt8500_gpio_chip {
+	struct gpio_chip	chip;
+	unsigned int		shift;
+	unsigned int		regoff;
+};
+
+static int gpio_to_irq_map[8];
+
+static int vt8500_muxed_gpio_request(struct gpio_chip *chip,
+				     unsigned offset)
+{
+	struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
+	unsigned val = readl(regbase + ENABLE_REGS + vt8500_chip->regoff);
+
+	val |= (1 << vt8500_chip->shift << offset);
+	writel(val, regbase + ENABLE_REGS + vt8500_chip->regoff);
+
+	return 0;
+}
+
+static void vt8500_muxed_gpio_free(struct gpio_chip *chip,
+				   unsigned offset)
+{
+	struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
+	unsigned val = readl(regbase + ENABLE_REGS + vt8500_chip->regoff);
+
+	val &= ~(1 << vt8500_chip->shift << offset);
+	writel(val, regbase + ENABLE_REGS + vt8500_chip->regoff);
+}
+
+static int vt8500_muxed_gpio_direction_input(struct gpio_chip *chip,
+				       unsigned offset)
+{
+	struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
+	unsigned val = readl(regbase + DIRECTION_REGS + vt8500_chip->regoff);
+
+	val &= ~(1 << vt8500_chip->shift << offset);
+	writel(val, regbase + DIRECTION_REGS + vt8500_chip->regoff);
+
+	return 0;
+}
+
+static int vt8500_muxed_gpio_direction_output(struct gpio_chip *chip,
+					unsigned offset, int value)
+{
+	struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
+	unsigned val = readl(regbase + DIRECTION_REGS + vt8500_chip->regoff);
+
+	val |= (1 << vt8500_chip->shift << offset);
+	writel(val, regbase + DIRECTION_REGS + vt8500_chip->regoff);
+
+	if (value) {
+		val = readl(regbase + OUTVALUE_REGS + vt8500_chip->regoff);
+		val |= (1 << vt8500_chip->shift << offset);
+		writel(val, regbase + OUTVALUE_REGS + vt8500_chip->regoff);
+	}
+	return 0;
+}
+
+static int vt8500_muxed_gpio_get_value(struct gpio_chip *chip,
+				       unsigned offset)
+{
+	struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
+
+	return (readl(regbase + INVALUE_REGS + vt8500_chip->regoff)
+		>> vt8500_chip->shift >> offset) & 1;
+}
+
+static void vt8500_muxed_gpio_set_value(struct gpio_chip *chip,
+					unsigned offset, int value)
+{
+	struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
+	unsigned val = readl(regbase + INVALUE_REGS + vt8500_chip->regoff);
+
+	if (value)
+		val |= (1 << vt8500_chip->shift << offset);
+	else
+		val &= ~(1 << vt8500_chip->shift << offset);
+
+	writel(val, regbase + INVALUE_REGS + vt8500_chip->regoff);
+}
+
+#define VT8500_GPIO_BANK(__name, __shift, __off, __base, __num)		\
+{									\
+	.chip = {							\
+		.label			= __name,			\
+		.request		= vt8500_muxed_gpio_request,	\
+		.free			= vt8500_muxed_gpio_free,	\
+		.direction_input  = vt8500_muxed_gpio_direction_input,	\
+		.direction_output = vt8500_muxed_gpio_direction_output,	\
+		.get			= vt8500_muxed_gpio_get_value,	\
+		.set			= vt8500_muxed_gpio_set_value,	\
+		.can_sleep		= 0,				\
+		.base			= __base,			\
+		.ngpio			= __num,			\
+	},								\
+	.shift		= __shift,					\
+	.regoff		= __off,					\
+}
+
+static struct vt8500_gpio_chip vt8500_muxed_gpios[] = {
+	VT8500_GPIO_BANK("uart0",	0,	0x0,	8,	4),
+	VT8500_GPIO_BANK("uart1",	4,	0x0,	12,	4),
+	VT8500_GPIO_BANK("spi0",	8,	0x0,	16,	4),
+	VT8500_GPIO_BANK("spi1",	12,	0x0,	20,	4),
+	VT8500_GPIO_BANK("spi2",	16,	0x0,	24,	4),
+	VT8500_GPIO_BANK("pwmout",	24,	0x0,	28,	2),
+
+	VT8500_GPIO_BANK("sdmmc",	0,	0x4,	30,	11),
+	VT8500_GPIO_BANK("ms",		16,	0x4,	41,	7),
+	VT8500_GPIO_BANK("i2c0",	24,	0x4,	48,	2),
+	VT8500_GPIO_BANK("i2c1",	26,	0x4,	50,	2),
+
+	VT8500_GPIO_BANK("mii",		0,	0x8,	52,	20),
+	VT8500_GPIO_BANK("see",		20,	0x8,	72,	4),
+	VT8500_GPIO_BANK("ide",		24,	0x8,	76,	7),
+
+	VT8500_GPIO_BANK("ccir",	0,	0xc,	83,	19),
+
+	VT8500_GPIO_BANK("ts",		8,	0x10,	102,	11),
+
+	VT8500_GPIO_BANK("lcd",		0,	0x14,	113,	23),
+};
+
+static int vt8500_gpio_direction_input(struct gpio_chip *chip,
+				       unsigned offset)
+{
+	unsigned val = readl(regbase + DIRECTION_REGS + EXT_REGOFF);
+
+	val &= ~(1 << offset);
+	writel(val, regbase + DIRECTION_REGS + EXT_REGOFF);
+	return 0;
+}
+
+static int vt8500_gpio_direction_output(struct gpio_chip *chip,
+					unsigned offset, int value)
+{
+	unsigned val = readl(regbase + DIRECTION_REGS + EXT_REGOFF);
+
+	val |= (1 << offset);
+	writel(val, regbase + DIRECTION_REGS + EXT_REGOFF);
+
+	if (value) {
+		val = readl(regbase + OUTVALUE_REGS + EXT_REGOFF);
+		val |= (1 << offset);
+		writel(val, regbase + OUTVALUE_REGS + EXT_REGOFF);
+	}
+	return 0;
+}
+
+static int vt8500_gpio_get_value(struct gpio_chip *chip,
+				       unsigned offset)
+{
+	return (readl(regbase + INVALUE_REGS + EXT_REGOFF) >> offset) & 1;
+}
+
+static void vt8500_gpio_set_value(struct gpio_chip *chip,
+					unsigned offset, int value)
+{
+	unsigned val = readl(regbase + OUTVALUE_REGS + EXT_REGOFF);
+
+	if (value)
+		val |= (1 << offset);
+	else
+		val &= ~(1 << offset);
+
+	writel(val, regbase + OUTVALUE_REGS + EXT_REGOFF);
+}
+
+static int vt8500_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+	if (offset > 7)
+		return -EINVAL;
+
+	return gpio_to_irq_map[offset];
+}
+
+static struct gpio_chip vt8500_external_gpios = {
+	.label			= "extgpio",
+	.direction_input	= vt8500_gpio_direction_input,
+	.direction_output	= vt8500_gpio_direction_output,
+	.get			= vt8500_gpio_get_value,
+	.set			= vt8500_gpio_set_value,
+	.to_irq			= vt8500_gpio_to_irq,
+	.can_sleep		= 0,
+	.base			= 0,
+	.ngpio			= 8,
+};
+
+void __init vt8500_gpio_init(void)
+{
+	int i;
+
+	for (i = 0; i < 8; i++)
+		gpio_to_irq_map[i] = wmt_gpio_ext_irq[i];
+
+	regbase = ioremap(wmt_gpio_base, SZ_64K);
+	if (!regbase) {
+		printk(KERN_ERR "Failed to map MMIO registers for GPIO\n");
+		return;
+	}
+
+	gpiochip_add(&vt8500_external_gpios);
+
+	for (i = 0; i < ARRAY_SIZE(vt8500_muxed_gpios); i++)
+		gpiochip_add(&vt8500_muxed_gpios[i].chip);
+}