1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * gpiolib support for Wolfson WM835x PMICs
4 *
5 * Copyright 2009 Wolfson Microelectronics PLC.
6 *
7 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
8 *
9 */
10
11#include <linux/kernel.h>
12#include <linux/slab.h>
13#include <linux/module.h>
14#include <linux/gpio/driver.h>
15#include <linux/mfd/core.h>
16#include <linux/platform_device.h>
17#include <linux/seq_file.h>
18
19#include <linux/mfd/wm8350/core.h>
20#include <linux/mfd/wm8350/gpio.h>
21
22struct wm8350_gpio_data {
23	struct wm8350 *wm8350;
24	struct gpio_chip gpio_chip;
25};
26
27static int wm8350_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
28{
29	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
30	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
31
32	return wm8350_set_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
33			       1 << offset);
34}
35
36static int wm8350_gpio_get(struct gpio_chip *chip, unsigned offset)
37{
38	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
39	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
40	int ret;
41
42	ret = wm8350_reg_read(wm8350, WM8350_GPIO_LEVEL);
43	if (ret < 0)
44		return ret;
45
46	if (ret & (1 << offset))
47		return 1;
48	else
49		return 0;
50}
51
52static void wm8350_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
53{
54	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
55	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
56
57	if (value)
58		wm8350_set_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
59	else
60		wm8350_clear_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
61}
62
63static int wm8350_gpio_direction_out(struct gpio_chip *chip,
64				     unsigned offset, int value)
65{
66	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
67	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
68	int ret;
69
70	ret = wm8350_clear_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
71				1 << offset);
72	if (ret < 0)
73		return ret;
74
75	/* Don't have an atomic direction/value setup */
76	wm8350_gpio_set(chip, offset, value);
77
78	return 0;
79}
80
81static int wm8350_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
82{
83	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
84	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
85
86	if (!wm8350->irq_base)
87		return -EINVAL;
88
89	return wm8350->irq_base + WM8350_IRQ_GPIO(offset);
90}
91
92static const struct gpio_chip template_chip = {
93	.label			= "wm8350",
94	.owner			= THIS_MODULE,
95	.direction_input	= wm8350_gpio_direction_in,
96	.get			= wm8350_gpio_get,
97	.direction_output	= wm8350_gpio_direction_out,
98	.set			= wm8350_gpio_set,
99	.to_irq			= wm8350_gpio_to_irq,
100	.can_sleep		= true,
101};
102
103static int wm8350_gpio_probe(struct platform_device *pdev)
104{
105	struct wm8350 *wm8350 = dev_get_drvdata(pdev->dev.parent);
106	struct wm8350_platform_data *pdata = dev_get_platdata(wm8350->dev);
107	struct wm8350_gpio_data *wm8350_gpio;
108	int ret;
109
110	wm8350_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8350_gpio),
111				   GFP_KERNEL);
112	if (wm8350_gpio == NULL)
113		return -ENOMEM;
114
115	wm8350_gpio->wm8350 = wm8350;
116	wm8350_gpio->gpio_chip = template_chip;
117	wm8350_gpio->gpio_chip.ngpio = 13;
118	wm8350_gpio->gpio_chip.parent = &pdev->dev;
119	if (pdata && pdata->gpio_base)
120		wm8350_gpio->gpio_chip.base = pdata->gpio_base;
121	else
122		wm8350_gpio->gpio_chip.base = -1;
123
124	ret = devm_gpiochip_add_data(&pdev->dev, &wm8350_gpio->gpio_chip,
125				     wm8350_gpio);
126	if (ret < 0) {
127		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
128		return ret;
129	}
130
131	platform_set_drvdata(pdev, wm8350_gpio);
132
133	return ret;
134}
135
136static struct platform_driver wm8350_gpio_driver = {
137	.driver.name	= "wm8350-gpio",
138	.probe		= wm8350_gpio_probe,
139};
140
141static int __init wm8350_gpio_init(void)
142{
143	return platform_driver_register(&wm8350_gpio_driver);
144}
145subsys_initcall(wm8350_gpio_init);
146
147static void __exit wm8350_gpio_exit(void)
148{
149	platform_driver_unregister(&wm8350_gpio_driver);
150}
151module_exit(wm8350_gpio_exit);
152
153MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
154MODULE_DESCRIPTION("GPIO interface for WM8350 PMICs");
155MODULE_LICENSE("GPL");
156MODULE_ALIAS("platform:wm8350-gpio");
157