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
22 struct wm8350_gpio_data {
23 struct wm8350 *wm8350;
24 struct gpio_chip gpio_chip;
25 };
26
wm8350_gpio_direction_in(struct gpio_chip * chip,unsigned offset)27 static 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
wm8350_gpio_get(struct gpio_chip * chip,unsigned offset)36 static 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
wm8350_gpio_set(struct gpio_chip * chip,unsigned offset,int value)52 static 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
wm8350_gpio_direction_out(struct gpio_chip * chip,unsigned offset,int value)63 static 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
wm8350_gpio_to_irq(struct gpio_chip * chip,unsigned offset)81 static 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
92 static 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
wm8350_gpio_probe(struct platform_device * pdev)103 static 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
136 static struct platform_driver wm8350_gpio_driver = {
137 .driver.name = "wm8350-gpio",
138 .probe = wm8350_gpio_probe,
139 };
140
wm8350_gpio_init(void)141 static int __init wm8350_gpio_init(void)
142 {
143 return platform_driver_register(&wm8350_gpio_driver);
144 }
145 subsys_initcall(wm8350_gpio_init);
146
wm8350_gpio_exit(void)147 static void __exit wm8350_gpio_exit(void)
148 {
149 platform_driver_unregister(&wm8350_gpio_driver);
150 }
151 module_exit(wm8350_gpio_exit);
152
153 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
154 MODULE_DESCRIPTION("GPIO interface for WM8350 PMICs");
155 MODULE_LICENSE("GPL");
156 MODULE_ALIAS("platform:wm8350-gpio");
157
