[PATCH v6 13/14] gpio: Add support for Airoha EN7523 GPIO controller

Felix Fietkau
2021-12-03T11:57:16Z

Airoha's GPIO controller on their ARM EN7523 SoCs consists of two banks of 32
GPIOs. Each instance in DT is for a single bank.

Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
drivers/gpio/Kconfig | 9 +++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-en7523.c | 134 +++++++++++++++++++++++++++++++++++++
3 files changed, 144 insertions(+)
create mode 100644 drivers/gpio/gpio-en7523.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 072ed610f9c6..e4a34272504f 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -247,6 +247,15 @@ config GPIO_EM
help
Say yes here to support GPIO on Renesas Emma Mobile SoCs.

+config GPIO_EN7523
+ tristate "Airoha GPIO support"
+ depends on ARCH_AIROHA
+ default ARCH_AIROHA
+ select GPIO_GENERIC
+ select GPIOLIB_IRQCHIP
+ help
+ Say yes here to support the GPIO controller on Airoha EN7523.
+
config GPIO_EP93XX
def_bool y
depends on ARCH_EP93XX
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 71ee9fc2ff83..d2269ee0948e 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -56,6 +56,7 @@ obj-$(CONFIG_GPIO_DLN2) += gpio-dln2.o
obj-$(CONFIG_GPIO_DWAPB) += gpio-dwapb.o
obj-$(CONFIG_GPIO_EIC_SPRD) += gpio-eic-sprd.o
obj-$(CONFIG_GPIO_EM) += gpio-em.o
+obj-$(CONFIG_GPIO_EN7523) += gpio-en7523.o
obj-$(CONFIG_GPIO_EP93XX) += gpio-ep93xx.o
obj-$(CONFIG_GPIO_EXAR) += gpio-exar.o
obj-$(CONFIG_GPIO_F7188X) += gpio-f7188x.o
diff --git a/drivers/gpio/gpio-en7523.c b/drivers/gpio/gpio-en7523.c
new file mode 100644
index 000000000000..07770c5a4101
--- /dev/null
+++ b/drivers/gpio/gpio-en7523.c
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/gpio/driver.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+
+#define AIROHA_GPIO_MAX 32
+
+/**
+ * airoha_gpio_ctrl - Airoha GPIO driver data
+ *
+ * @gc: Associated gpio_chip instance.
+ * @data: The data register.
+ * @dir0: The direction register for the lower 16 pins.
+ * @dir1: The direction register for the higher 16 pins.
+ * @output: The output enable register.
+ */
+struct airoha_gpio_ctrl {
+ struct gpio_chip gc;
+ void __iomem *data;
+ void __iomem *dir[2];
+ void __iomem *output;
+};
+
+static struct airoha_gpio_ctrl *gc_to_ctrl(struct gpio_chip *gc)
+{
+ return container_of(gc, struct airoha_gpio_ctrl, gc);
+}
+
+static int airoha_dir_set(struct gpio_chip *gc, unsigned int gpio,
+ int val, int out)
+{
+ struct airoha_gpio_ctrl *ctrl = gc_to_ctrl(gc);
+ u32 dir = ioread32(ctrl->dir[gpio / 16]);
+ u32 output = ioread32(ctrl->output);
+ u32 mask = BIT((gpio % 16) * 2);
+
+ if (out) {
+ dir |= mask;
+ output |= BIT(gpio);
+ } else {
+ dir &= ~mask;
+ output &= ~BIT(gpio);
+ }
+
+ iowrite32(dir, ctrl->dir[gpio / 16]);
+ iowrite32(output, ctrl->output);
+
+ if (out)
+ gc->set(gc, gpio, val);
+
+ return 0;
+}
+
+static int airoha_dir_out(struct gpio_chip *gc, unsigned int gpio,
+ int val)
+{
+ return airoha_dir_set(gc, gpio, val, 1);
+}
+
+static int airoha_dir_in(struct gpio_chip *gc, unsigned int gpio)
+{
+ return airoha_dir_set(gc, gpio, 0, 0);
+}
+
+static int airoha_get_dir(struct gpio_chip *gc, unsigned int gpio)
+{
+ struct airoha_gpio_ctrl *ctrl = gc_to_ctrl(gc);
+ u32 dir = ioread32(ctrl->dir[gpio / 16]);
+ u32 mask = BIT((gpio % 16) * 2);
+
+ return dir & mask;
+}
+
+static const struct of_device_id airoha_gpio_of_match[] = {
+ { .compatible = "airoha,en7523-gpio" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, airoha_gpio_of_match);
+
+static int airoha_gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct airoha_gpio_ctrl *ctrl;
+ int err;
+
+ ctrl = devm_kzalloc(dev, sizeof(*ctrl), GFP_KERNEL);
+ if (!ctrl)
+ return -ENOMEM;
+
+ ctrl->data = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(ctrl->data))
+ return PTR_ERR(ctrl->data);
+
+ ctrl->dir[0] = devm_platform_ioremap_resource(pdev, 1);
+ if (IS_ERR(ctrl->dir[0]))
+ return PTR_ERR(ctrl->dir[0]);
+
+ ctrl->dir[1] = devm_platform_ioremap_resource(pdev, 2);
+ if (IS_ERR(ctrl->dir[1]))
+ return PTR_ERR(ctrl->dir[1]);
+
+ ctrl->output = devm_platform_ioremap_resource(pdev, 3);
+ if (IS_ERR(ctrl->output))
+ return PTR_ERR(ctrl->output);
+
+ err = bgpio_init(&ctrl->gc, dev, 4, ctrl->data, NULL,
+ NULL, NULL, NULL, 0);
+ if (err)
+ return dev_err_probe(dev, err, "unable to init generic GPIO");
+
+ ctrl->gc.ngpio = AIROHA_GPIO_MAX;
+ ctrl->gc.owner = THIS_MODULE;
+ ctrl->gc.direction_output = airoha_dir_out;
+ ctrl->gc.direction_input = airoha_dir_in;
+ ctrl->gc.get_direction = airoha_get_dir;
+
+ return devm_gpiochip_add_data(dev, &ctrl->gc, ctrl);
+}
+
+static struct platform_driver airoha_gpio_driver = {
+ .driver = {
+ .name = "airoha-gpio",
+ .of_match_table = airoha_gpio_of_match,
+ },
+ .probe = airoha_gpio_probe,
+};
+module_platform_driver(airoha_gpio_driver);
+
+MODULE_DESCRIPTION("Airoha GPIO support");
+MODULE_AUTHOR("John Crispin <john@phrozen.org>");
+MODULE_LICENSE("GPL v2");
--
2.30.1