diff options
Diffstat (limited to 'drivers/gpio/gpio-en7523.c')
| -rw-r--r-- | drivers/gpio/gpio-en7523.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-en7523.c b/drivers/gpio/gpio-en7523.c new file mode 100644 index 000000000..f836a8db4 --- /dev/null +++ b/drivers/gpio/gpio-en7523.c @@ -0,0 +1,137 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <linux/types.h> +#include <linux/io.h> +#include <linux/bits.h> +#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]); + + if (out) + gc->set(gc, gpio, val); + + iowrite32(output, ctrl->output); + + 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) ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN; +} + +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 const struct of_device_id airoha_gpio_of_match[] = { + { .compatible = "airoha,en7523-gpio" }, + { } +}; +MODULE_DEVICE_TABLE(of, airoha_gpio_of_match); + +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"); |