xref: /openbmc/linux/drivers/gpio/gpio-wm8350.c (revision 5d331b7f)
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 
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 
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 
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 
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 
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 
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 
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 
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