gpio-en7523.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2
  3#include <linux/types.h>
  4#include <linux/io.h>
  5#include <linux/bits.h>
  6#include <linux/gpio/driver.h>
  7#include <linux/gpio/generic.h>
  8#include <linux/mod_devicetable.h>
  9#include <linux/module.h>
 10#include <linux/platform_device.h>
 11#include <linux/property.h>
 12
 13#define AIROHA_GPIO_MAX		32
 14
 15/**
 16 * struct airoha_gpio_ctrl - Airoha GPIO driver data
 17 * @gen_gc: Associated gpio_generic_chip instance.
 18 * @data: The data register.
 19 * @dir: [0] The direction register for the lower 16 pins.
 20 * [1]: The direction register for the higher 16 pins.
 21 * @output: The output enable register.
 22 */
 23struct airoha_gpio_ctrl {
 24	struct gpio_generic_chip gen_gc;
 25	void __iomem *data;
 26	void __iomem *dir[2];
 27	void __iomem *output;
 28};
 29
 30static int airoha_dir_set(struct gpio_chip *gc, unsigned int gpio,
 31			  int val, int out)
 32{
 33	struct airoha_gpio_ctrl *ctrl = gpiochip_get_data(gc);
 34	u32 dir = ioread32(ctrl->dir[gpio / 16]);
 35	u32 output = ioread32(ctrl->output);
 36	u32 mask = BIT((gpio % 16) * 2);
 37
 38	if (out) {
 39		dir |= mask;
 40		output |= BIT(gpio);
 41	} else {
 42		dir &= ~mask;
 43		output &= ~BIT(gpio);
 44	}
 45
 46	iowrite32(dir, ctrl->dir[gpio / 16]);
 47
 48	if (out)
 49		gpio_generic_chip_set(&ctrl->gen_gc, gpio, val);
 50
 51	iowrite32(output, ctrl->output);
 52
 53	return 0;
 54}
 55
 56static int airoha_dir_out(struct gpio_chip *gc, unsigned int gpio,
 57			  int val)
 58{
 59	return airoha_dir_set(gc, gpio, val, 1);
 60}
 61
 62static int airoha_dir_in(struct gpio_chip *gc, unsigned int gpio)
 63{
 64	return airoha_dir_set(gc, gpio, 0, 0);
 65}
 66
 67static int airoha_get_dir(struct gpio_chip *gc, unsigned int gpio)
 68{
 69	struct airoha_gpio_ctrl *ctrl = gpiochip_get_data(gc);
 70	u32 dir = ioread32(ctrl->dir[gpio / 16]);
 71	u32 mask = BIT((gpio % 16) * 2);
 72
 73	return (dir & mask) ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
 74}
 75
 76static int airoha_gpio_probe(struct platform_device *pdev)
 77{
 78	struct gpio_generic_chip_config config = { };
 79	struct device *dev = &pdev->dev;
 80	struct airoha_gpio_ctrl *ctrl;
 81	int err;
 82
 83	ctrl = devm_kzalloc(dev, sizeof(*ctrl), GFP_KERNEL);
 84	if (!ctrl)
 85		return -ENOMEM;
 86
 87	ctrl->data = devm_platform_ioremap_resource(pdev, 0);
 88	if (IS_ERR(ctrl->data))
 89		return PTR_ERR(ctrl->data);
 90
 91	ctrl->dir[0] = devm_platform_ioremap_resource(pdev, 1);
 92	if (IS_ERR(ctrl->dir[0]))
 93		return PTR_ERR(ctrl->dir[0]);
 94
 95	ctrl->dir[1] = devm_platform_ioremap_resource(pdev, 2);
 96	if (IS_ERR(ctrl->dir[1]))
 97		return PTR_ERR(ctrl->dir[1]);
 98
 99	ctrl->output = devm_platform_ioremap_resource(pdev, 3);
100	if (IS_ERR(ctrl->output))
101		return PTR_ERR(ctrl->output);
102
103	config.dev = dev;
104	config.sz = 4;
105	config.dat = ctrl->data;
106
107	err = gpio_generic_chip_init(&ctrl->gen_gc, &config);
108	if (err)
109		return dev_err_probe(dev, err, "unable to init generic GPIO");
110
111	ctrl->gen_gc.gc.ngpio = AIROHA_GPIO_MAX;
112	ctrl->gen_gc.gc.owner = THIS_MODULE;
113	ctrl->gen_gc.gc.direction_output = airoha_dir_out;
114	ctrl->gen_gc.gc.direction_input = airoha_dir_in;
115	ctrl->gen_gc.gc.get_direction = airoha_get_dir;
116
117	return devm_gpiochip_add_data(dev, &ctrl->gen_gc.gc, ctrl);
118}
119
120static const struct of_device_id airoha_gpio_of_match[] = {
121	{ .compatible = "airoha,en7523-gpio" },
122	{ }
123};
124MODULE_DEVICE_TABLE(of, airoha_gpio_of_match);
125
126static struct platform_driver airoha_gpio_driver = {
127	.driver = {
128		.name = "airoha-gpio",
129		.of_match_table	= airoha_gpio_of_match,
130	},
131	.probe = airoha_gpio_probe,
132};
133module_platform_driver(airoha_gpio_driver);
134
135MODULE_DESCRIPTION("Airoha GPIO support");
136MODULE_AUTHOR("John Crispin <john@phrozen.org>");
137MODULE_LICENSE("GPL v2");