Add gpio driver for Actions Semi OWL family S900 SoC. Set of registers
controlling the gpio shares the same register range with pinctrl block.
GPIO registers are organized as 6 banks and each bank controls the
maximum of 32 gpios.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasi...@linaro.org>
Reviewed-by: Andy Shevchenko <andy.shevche...@gmail.com>
---
drivers/gpio/Kconfig | 8 +++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-owl.c | 184 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 193 insertions(+)
create mode 100644 drivers/gpio/gpio-owl.c
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 8dbb2280538d..75533f55ad0e 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -364,6 +364,14 @@ config GPIO_OMAP
help
Say yes here to enable GPIO support for TI OMAP SoCs.
+config GPIO_OWL
+ tristate "Actions Semi OWL GPIO support"
+ default ARCH_ACTIONS
+ depends on ARCH_ACTIONS || COMPILE_TEST
+ depends on OF_GPIO
+ help
+ Say yes here to enable GPIO support for Actions Semi OWL SoCs.
+
config GPIO_PL061
bool "PrimeCell PL061 GPIO support"
depends on ARM_AMBA
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index cccb0d40846c..b2bb11d4675f 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -91,6 +91,7 @@ obj-$(CONFIG_GPIO_MXC) += gpio-mxc.o
obj-$(CONFIG_GPIO_MXS) += gpio-mxs.o
obj-$(CONFIG_GPIO_OCTEON) += gpio-octeon.o
obj-$(CONFIG_GPIO_OMAP) += gpio-omap.o
+obj-$(CONFIG_GPIO_OWL) += gpio-owl.o
obj-$(CONFIG_GPIO_PCA953X) += gpio-pca953x.o
obj-$(CONFIG_GPIO_PCF857X) += gpio-pcf857x.o
obj-$(CONFIG_GPIO_PCH) += gpio-pch.o
diff --git a/drivers/gpio/gpio-owl.c b/drivers/gpio/gpio-owl.c
new file mode 100644
index 000000000000..354636229fee
--- /dev/null
+++ b/drivers/gpio/gpio-owl.c
@@ -0,0 +1,184 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * OWL SoC's GPIO driver
+ *
+ * Copyright (c) 2018 Linaro Ltd.
+ * Author: Manivannan Sadhasivam <manivannan.sadhasi...@linaro.org>
+ */
+
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/gpio/driver.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#define GPIO_OUTEN 0x0000
+#define GPIO_INEN 0x0004
+#define GPIO_DAT 0x0008
+
+struct owl_gpio {
+ struct gpio_chip gpio;
+ void __iomem *base;
+ spinlock_t lock;
+};
+
+static void owl_gpio_update_reg(void __iomem *base, unsigned int pin, int flag)
+{
+ u32 val;
+
+ val = readl_relaxed(base);
+
+ if (flag)
+ val |= BIT(pin);
+ else
+ val &= ~BIT(pin);
+
+ writel_relaxed(val, base);
+}
+
+static int owl_gpio_request(struct gpio_chip *chip, unsigned int offset)
+{
+ struct owl_gpio *gpio = gpiochip_get_data(chip);
+
+ /*
+ * GPIOs have higher priority over other modules, so either setting
+ * them as OUT or IN is sufficient
+ */
+ spin_lock(&gpio->lock);
+ owl_gpio_update_reg(gpio->base + GPIO_OUTEN, offset, true);
+ spin_unlock(&gpio->lock);
+
+ return 0;
+}
+
+static void owl_gpio_free(struct gpio_chip *chip, unsigned int offset)
+{
+ struct owl_gpio *gpio = gpiochip_get_data(chip);
+
+ spin_lock(&gpio->lock);
+ /* disable gpio output */
+ owl_gpio_update_reg(gpio->base + GPIO_OUTEN, offset, false);
+
+ /* disable gpio input */
+ owl_gpio_update_reg(gpio->base + GPIO_INEN, offset, false);
+ spin_unlock(&gpio->lock);
+}
+
+static int owl_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct owl_gpio *gpio = gpiochip_get_data(chip);
+ u32 val;
+
+ spin_lock(&gpio->lock);
+ val = readl_relaxed(gpio->base + GPIO_DAT);
+ spin_unlock(&gpio->lock);
+
+ return !!(val & BIT(offset));
+}
+
+static void owl_gpio_set(struct gpio_chip *chip, unsigned int offset, int
value)
+{
+ struct owl_gpio *gpio = gpiochip_get_data(chip);
+
+ spin_lock(&gpio->lock);
+ owl_gpio_update_reg(gpio->base + GPIO_DAT, offset, value);
+ spin_unlock(&gpio->lock);
+}
+
+static int owl_gpio_direction_input(struct gpio_chip *chip, unsigned int
offset)
+{
+ struct owl_gpio *gpio = gpiochip_get_data(chip);
+
+ spin_lock(&gpio->lock);
+ owl_gpio_update_reg(gpio->base + GPIO_OUTEN, offset, false);
+ owl_gpio_update_reg(gpio->base + GPIO_INEN, offset, true);
+ spin_unlock(&gpio->lock);
+
+ return 0;
+}
+
+static int owl_gpio_direction_output(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ struct owl_gpio *gpio = gpiochip_get_data(chip);
+
+ spin_lock(&gpio->lock);
+ owl_gpio_update_reg(gpio->base + GPIO_INEN, offset, false);
+ owl_gpio_update_reg(gpio->base + GPIO_OUTEN, offset, true);
+ owl_gpio_update_reg(gpio->base + GPIO_DAT, offset, value);
+ spin_unlock(&gpio->lock);
+
+ return 0;
+}
+
+static int owl_gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct owl_gpio *gpio;
+ u32 ngpios;
+ int ret;
+
+ gpio = devm_kzalloc(dev, sizeof(*gpio), GFP_KERNEL);
+ if (!gpio)
+ return -ENOMEM;
+
+ gpio->base = of_iomap(dev->of_node, 0);
+ if (IS_ERR(gpio->base))
+ return PTR_ERR(gpio->base);
+
+ /*
+ * Get the number of gpio's for this bank. If none specified,
+ * then fall back to 32.
+ */
+ ret = of_property_read_u32(dev->of_node, "ngpios", &ngpios);
+ if (ret)
+ ngpios = 32;
+
+ spin_lock_init(&gpio->lock);
+
+ gpio->gpio.request = owl_gpio_request;
+ gpio->gpio.free = owl_gpio_free;
+ gpio->gpio.get = owl_gpio_get;
+ gpio->gpio.set = owl_gpio_set;
+ gpio->gpio.direction_input = owl_gpio_direction_input;
+ gpio->gpio.direction_output = owl_gpio_direction_output;
+
+ gpio->gpio.base = -1;
+ gpio->gpio.parent = dev;
+ gpio->gpio.label = dev_name(dev);
+ gpio->gpio.ngpio = ngpios;
+
+ platform_set_drvdata(pdev, gpio);
+
+ ret = devm_gpiochip_add_data(dev, &gpio->gpio, gpio);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to register gpiochip\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id owl_gpio_of_match[] = {
+ { .compatible = "actions,s900-gpio", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, owl_gpio_of_match);
+
+static struct platform_driver owl_gpio_driver = {
+ .driver = {
+ .name = "owl-gpio",
+ .of_match_table = owl_gpio_of_match,
+ },
+ .probe = owl_gpio_probe,
+};
+module_platform_driver(owl_gpio_driver);
+
+MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasi...@linaro.org>");
+MODULE_DESCRIPTION("Actions Semi OWL SoCs GPIO driver");
+MODULE_LICENSE("GPL");
--
2.14.1
