Fixed MTP to work with TWRP

drivers/gpio/gpio-iop.c

@@ -0,0 +1,132 @@
+/*
+ * arch/arm/plat-iop/gpio.c
+ * GPIO handling for Intel IOP3xx processors.
+ *
+ * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.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.
+ */
+
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/gpio.h>
+#include <linux/export.h>
+#include <linux/platform_device.h>
+#include <linux/bitops.h>
+#include <linux/io.h>
+
+#define IOP3XX_N_GPIOS	8
+
+#define GPIO_IN			0
+#define GPIO_OUT		1
+#define GPIO_LOW		0
+#define GPIO_HIGH		1
+
+/* Memory base offset */
+static void __iomem *base;
+
+#define IOP3XX_GPIO_REG(reg)	(base + (reg))
+#define IOP3XX_GPOE		IOP3XX_GPIO_REG(0x0000)
+#define IOP3XX_GPID		IOP3XX_GPIO_REG(0x0004)
+#define IOP3XX_GPOD		IOP3XX_GPIO_REG(0x0008)
+
+static void gpio_line_config(int line, int direction)
+{
+	unsigned long flags;
+	u32 val;
+
+	local_irq_save(flags);
+	val = readl(IOP3XX_GPOE);
+	if (direction == GPIO_IN) {
+		val |= BIT(line);
+	} else if (direction == GPIO_OUT) {
+		val &= ~BIT(line);
+	}
+	writel(val, IOP3XX_GPOE);
+	local_irq_restore(flags);
+}
+
+static int gpio_line_get(int line)
+{
+	return !!(readl(IOP3XX_GPID) & BIT(line));
+}
+
+static void gpio_line_set(int line, int value)
+{
+	unsigned long flags;
+	u32 val;
+
+	local_irq_save(flags);
+	val = readl(IOP3XX_GPOD);
+	if (value == GPIO_LOW) {
+		val &= ~BIT(line);
+	} else if (value == GPIO_HIGH) {
+		val |= BIT(line);
+	}
+	writel(val, IOP3XX_GPOD);
+	local_irq_restore(flags);
+}
+
+static int iop3xx_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
+{
+	gpio_line_config(gpio, GPIO_IN);
+	return 0;
+}
+
+static int iop3xx_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, int level)
+{
+	gpio_line_set(gpio, level);
+	gpio_line_config(gpio, GPIO_OUT);
+	return 0;
+}
+
+static int iop3xx_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
+{
+	return gpio_line_get(gpio);
+}
+
+static void iop3xx_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value)
+{
+	gpio_line_set(gpio, value);
+}
+
+static struct gpio_chip iop3xx_chip = {
+	.label			= "iop3xx",
+	.direction_input	= iop3xx_gpio_direction_input,
+	.get			= iop3xx_gpio_get_value,
+	.direction_output	= iop3xx_gpio_direction_output,
+	.set			= iop3xx_gpio_set_value,
+	.base			= 0,
+	.ngpio			= IOP3XX_N_GPIOS,
+};
+
+static int iop3xx_gpio_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	return gpiochip_add(&iop3xx_chip);
+}
+
+static struct platform_driver iop3xx_gpio_driver = {
+	.driver = {
+		.name = "gpio-iop",
+		.owner = THIS_MODULE,
+	},
+	.probe = iop3xx_gpio_probe,
+};
+
+static int __init iop3xx_gpio_init(void)
+{
+	return platform_driver_register(&iop3xx_gpio_driver);
+}
+arch_initcall(iop3xx_gpio_init);