aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/mcs814x/files-3.3/drivers/gpio/gpio-mcs814x.c
diff options
context:
space:
mode:
Diffstat (limited to 'target/linux/mcs814x/files-3.3/drivers/gpio/gpio-mcs814x.c')
-rw-r--r--target/linux/mcs814x/files-3.3/drivers/gpio/gpio-mcs814x.c148
1 files changed, 148 insertions, 0 deletions
diff --git a/target/linux/mcs814x/files-3.3/drivers/gpio/gpio-mcs814x.c b/target/linux/mcs814x/files-3.3/drivers/gpio/gpio-mcs814x.c
new file mode 100644
index 000000000..f1382290f
--- /dev/null
+++ b/target/linux/mcs814x/files-3.3/drivers/gpio/gpio-mcs814x.c
@@ -0,0 +1,148 @@
+/*
+ * Moschip MCS814x GPIO support
+ *
+ * Copyright (C) 2012, Florian Fainelli <florian@openwrt.org>
+ *
+ * Licensed under the GPLv2
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+struct mcs814x_gpio_chip {
+ void __iomem *regs;
+ struct gpio_chip chip;
+};
+
+#define GPIO_PIN 0x00
+#define GPIO_DIR 0x04
+
+#define to_mcs814x_gpio_chip(x) container_of(x, struct mcs814x_gpio_chip, chip)
+
+static int mcs814x_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct mcs814x_gpio_chip *mcs814x = to_mcs814x_gpio_chip(chip);
+
+ return readl_relaxed(mcs814x->regs + GPIO_PIN) & (1 << offset);
+}
+
+static void mcs814x_gpio_set(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ struct mcs814x_gpio_chip *mcs814x = to_mcs814x_gpio_chip(chip);
+ u32 mask;
+
+ mask = readl_relaxed(mcs814x->regs + GPIO_PIN);
+ if (value)
+ mask |= (1 << offset);
+ else
+ mask &= ~(1 << offset);
+ writel_relaxed(mask, mcs814x->regs + GPIO_PIN);
+}
+
+static int mcs814x_gpio_direction_output(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ struct mcs814x_gpio_chip *mcs814x = to_mcs814x_gpio_chip(chip);
+ u32 mask;
+
+ mask = readl_relaxed(mcs814x->regs + GPIO_DIR);
+ mask &= ~(1 << offset);
+ writel_relaxed(mask, mcs814x->regs + GPIO_DIR);
+
+ return 0;
+}
+
+static int mcs814x_gpio_direction_input(struct gpio_chip *chip,
+ unsigned offset)
+{
+ struct mcs814x_gpio_chip *mcs814x = to_mcs814x_gpio_chip(chip);
+ u32 mask;
+
+ mask = readl_relaxed(mcs814x->regs + GPIO_DIR);
+ mask |= (1 << offset);
+ writel_relaxed(mask, mcs814x->regs + GPIO_DIR);
+
+ return 0;
+}
+
+static int __devinit mcs814x_gpio_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct mcs814x_gpio_chip *mcs814x_chip;
+ int ret;
+ const unsigned int *num_gpios;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ num_gpios = of_get_property(pdev->dev.of_node, "num-gpios", NULL);
+ if (!num_gpios)
+ dev_err(&pdev->dev, "FIXME: no num-gpios property\n");
+
+ mcs814x_chip = kzalloc(sizeof(*mcs814x_chip), GFP_KERNEL);
+ if (!mcs814x_chip)
+ return -ENOMEM;
+
+ mcs814x_chip->regs = devm_request_and_ioremap(&pdev->dev, res);
+ if (!mcs814x_chip->regs) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ platform_set_drvdata(pdev, mcs814x_chip);
+
+#ifdef CONFIG_OF_GPIO
+ mcs814x_chip->chip.of_node = pdev->dev.of_node;
+#endif
+
+ mcs814x_chip->chip.label = pdev->name;
+ mcs814x_chip->chip.get = mcs814x_gpio_get;
+ mcs814x_chip->chip.set = mcs814x_gpio_set;
+ mcs814x_chip->chip.direction_input = mcs814x_gpio_direction_input;
+ mcs814x_chip->chip.direction_output = mcs814x_gpio_direction_output;
+ mcs814x_chip->chip.ngpio = be32_to_cpup(num_gpios);
+ /* we want dynamic base allocation */
+ mcs814x_chip->chip.base = -1;
+
+ ret = gpiochip_add(&mcs814x_chip->chip);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register gpiochip\n");
+ goto out;
+ }
+
+ return 0;
+
+out:
+ platform_set_drvdata(pdev, NULL);
+ kfree(mcs814x_chip);
+ return ret;
+}
+
+static struct of_device_id mcs814x_gpio_ids[] __devinitdata = {
+ { .compatible = "moschip,mcs814x-gpio" },
+ { /* sentinel */ },
+};
+
+static struct platform_driver mcs814x_gpio_driver = {
+ .driver = {
+ .name = "mcs814x-gpio",
+ .owner = THIS_MODULE,
+ .of_match_table = mcs814x_gpio_ids,
+ },
+ .probe = mcs814x_gpio_probe,
+};
+
+int __init mcs814x_gpio_init(void)
+{
+ return platform_driver_register(&mcs814x_gpio_driver);
+}
+postcore_initcall(mcs814x_gpio_init);