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path: root/drivers/gpio/gpio-moxart.c
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Diffstat (limited to 'drivers/gpio/gpio-moxart.c')
-rw-r--r--drivers/gpio/gpio-moxart.c162
1 files changed, 162 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-moxart.c b/drivers/gpio/gpio-moxart.c
new file mode 100644
index 000000000000..d662cdededac
--- /dev/null
+++ b/drivers/gpio/gpio-moxart.c
@@ -0,0 +1,162 @@
+/*
+ * MOXA ART SoCs GPIO driver.
+ *
+ * Copyright (C) 2013 Jonas Jensen
+ *
+ * Jonas Jensen <jonas.jensen@gmail.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_gpio.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/delay.h>
+#include <linux/timer.h>
+#include <linux/bitops.h>
+
+#define GPIO_DATA_OUT 0x00
+#define GPIO_DATA_IN 0x04
+#define GPIO_PIN_DIRECTION 0x08
+
+struct moxart_gpio_chip {
+ struct gpio_chip gpio;
+ void __iomem *moxart_gpio_base;
+};
+
+static inline struct moxart_gpio_chip *to_moxart_gpio(struct gpio_chip *chip)
+{
+ return container_of(chip, struct moxart_gpio_chip, gpio);
+}
+
+static int moxart_gpio_request(struct gpio_chip *chip, unsigned offset)
+{
+ return pinctrl_request_gpio(offset);
+}
+
+static void moxart_gpio_free(struct gpio_chip *chip, unsigned offset)
+{
+ pinctrl_free_gpio(offset);
+}
+
+static int moxart_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+ struct moxart_gpio_chip *gc = to_moxart_gpio(chip);
+ void __iomem *ioaddr = gc->moxart_gpio_base + GPIO_PIN_DIRECTION;
+
+ writel(readl(ioaddr) & ~BIT(offset), ioaddr);
+ return 0;
+}
+
+static int moxart_gpio_direction_output(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ struct moxart_gpio_chip *gc = to_moxart_gpio(chip);
+ void __iomem *ioaddr = gc->moxart_gpio_base + GPIO_PIN_DIRECTION;
+
+ writel(readl(ioaddr) | BIT(offset), ioaddr);
+ return 0;
+}
+
+static void moxart_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ struct moxart_gpio_chip *gc = to_moxart_gpio(chip);
+ void __iomem *ioaddr = gc->moxart_gpio_base + GPIO_DATA_OUT;
+ u32 reg = readl(ioaddr);
+
+ if (value)
+ reg = reg | BIT(offset);
+ else
+ reg = reg & ~BIT(offset);
+
+
+ writel(reg, ioaddr);
+}
+
+static int moxart_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct moxart_gpio_chip *gc = to_moxart_gpio(chip);
+ u32 ret = readl(gc->moxart_gpio_base + GPIO_PIN_DIRECTION);
+
+ if (ret & BIT(offset))
+ return !!(readl(gc->moxart_gpio_base + GPIO_DATA_OUT) &
+ BIT(offset));
+ else
+ return !!(readl(gc->moxart_gpio_base + GPIO_DATA_IN) &
+ BIT(offset));
+}
+
+static struct gpio_chip moxart_template_chip = {
+ .label = "moxart-gpio",
+ .request = moxart_gpio_request,
+ .free = moxart_gpio_free,
+ .direction_input = moxart_gpio_direction_input,
+ .direction_output = moxart_gpio_direction_output,
+ .set = moxart_gpio_set,
+ .get = moxart_gpio_get,
+ .base = 0,
+ .ngpio = 32,
+ .can_sleep = 0,
+};
+
+static int moxart_gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ struct moxart_gpio_chip *mgc;
+ int ret;
+
+ mgc = devm_kzalloc(dev, sizeof(*mgc), GFP_KERNEL);
+ if (!mgc) {
+ dev_err(dev, "can't allocate GPIO chip container\n");
+ return -ENOMEM;
+ }
+ mgc->gpio = moxart_template_chip;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ mgc->moxart_gpio_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(mgc->moxart_gpio_base)) {
+ dev_err(dev, "%s: devm_ioremap_resource res_gpio failed\n",
+ dev->of_node->full_name);
+ return PTR_ERR(mgc->moxart_gpio_base);
+ }
+
+ mgc->gpio.dev = dev;
+
+ ret = gpiochip_add(&mgc->gpio);
+ if (ret) {
+ dev_err(dev, "%s: gpiochip_add failed\n",
+ dev->of_node->full_name);
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id moxart_gpio_match[] = {
+ { .compatible = "moxa,moxart-gpio" },
+ { }
+};
+
+static struct platform_driver moxart_gpio_driver = {
+ .driver = {
+ .name = "moxart-gpio",
+ .owner = THIS_MODULE,
+ .of_match_table = moxart_gpio_match,
+ },
+ .probe = moxart_gpio_probe,
+};
+module_platform_driver(moxart_gpio_driver);
+
+MODULE_DESCRIPTION("MOXART GPIO chip driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");