xref: /openbmc/linux/drivers/gpio/gpio-tps6586x.c (revision a8da474e)
1 /*
2  * TI TPS6586x GPIO driver
3  *
4  * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
5  * Author: Laxman dewangan <ldewangan@nvidia.com>
6  *
7  * Based on tps6586x.c
8  * Copyright (c) 2010 CompuLab Ltd.
9  * Mike Rapoport <mike@compulab.co.il>
10  *
11  * This program is free software; you can redistribute it and/or modify it
12  * under the terms and conditions of the GNU General Public License,
13  * version 2, as published by the Free Software Foundation.
14  *
15  * This program is distributed in the hope it will be useful, but WITHOUT
16  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
17  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
18  * more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
22  */
23 
24 #include <linux/errno.h>
25 #include <linux/gpio.h>
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/mfd/tps6586x.h>
29 #include <linux/of_device.h>
30 #include <linux/platform_device.h>
31 
32 /* GPIO control registers */
33 #define TPS6586X_GPIOSET1	0x5d
34 #define TPS6586X_GPIOSET2	0x5e
35 
36 struct tps6586x_gpio {
37 	struct gpio_chip gpio_chip;
38 	struct device *parent;
39 };
40 
41 static inline struct tps6586x_gpio *to_tps6586x_gpio(struct gpio_chip *chip)
42 {
43 	return container_of(chip, struct tps6586x_gpio, gpio_chip);
44 }
45 
46 static int tps6586x_gpio_get(struct gpio_chip *gc, unsigned offset)
47 {
48 	struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc);
49 	uint8_t val;
50 	int ret;
51 
52 	ret = tps6586x_read(tps6586x_gpio->parent, TPS6586X_GPIOSET2, &val);
53 	if (ret)
54 		return ret;
55 
56 	return !!(val & (1 << offset));
57 }
58 
59 static void tps6586x_gpio_set(struct gpio_chip *gc, unsigned offset,
60 			      int value)
61 {
62 	struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc);
63 
64 	tps6586x_update(tps6586x_gpio->parent, TPS6586X_GPIOSET2,
65 			value << offset, 1 << offset);
66 }
67 
68 static int tps6586x_gpio_output(struct gpio_chip *gc, unsigned offset,
69 				int value)
70 {
71 	struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc);
72 	uint8_t val, mask;
73 
74 	tps6586x_gpio_set(gc, offset, value);
75 
76 	val = 0x1 << (offset * 2);
77 	mask = 0x3 << (offset * 2);
78 
79 	return tps6586x_update(tps6586x_gpio->parent, TPS6586X_GPIOSET1,
80 				val, mask);
81 }
82 
83 static int tps6586x_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
84 {
85 	struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc);
86 
87 	return tps6586x_irq_get_virq(tps6586x_gpio->parent,
88 				TPS6586X_INT_PLDO_0 + offset);
89 }
90 
91 static int tps6586x_gpio_probe(struct platform_device *pdev)
92 {
93 	struct tps6586x_platform_data *pdata;
94 	struct tps6586x_gpio *tps6586x_gpio;
95 	int ret;
96 
97 	pdata = dev_get_platdata(pdev->dev.parent);
98 	tps6586x_gpio = devm_kzalloc(&pdev->dev,
99 				sizeof(*tps6586x_gpio), GFP_KERNEL);
100 	if (!tps6586x_gpio)
101 		return -ENOMEM;
102 
103 	tps6586x_gpio->parent = pdev->dev.parent;
104 
105 	tps6586x_gpio->gpio_chip.owner = THIS_MODULE;
106 	tps6586x_gpio->gpio_chip.label = pdev->name;
107 	tps6586x_gpio->gpio_chip.dev = &pdev->dev;
108 	tps6586x_gpio->gpio_chip.ngpio = 4;
109 	tps6586x_gpio->gpio_chip.can_sleep = true;
110 
111 	/* FIXME: add handling of GPIOs as dedicated inputs */
112 	tps6586x_gpio->gpio_chip.direction_output = tps6586x_gpio_output;
113 	tps6586x_gpio->gpio_chip.set	= tps6586x_gpio_set;
114 	tps6586x_gpio->gpio_chip.get	= tps6586x_gpio_get;
115 	tps6586x_gpio->gpio_chip.to_irq	= tps6586x_gpio_to_irq;
116 
117 #ifdef CONFIG_OF_GPIO
118 	tps6586x_gpio->gpio_chip.of_node = pdev->dev.parent->of_node;
119 #endif
120 	if (pdata && pdata->gpio_base)
121 		tps6586x_gpio->gpio_chip.base = pdata->gpio_base;
122 	else
123 		tps6586x_gpio->gpio_chip.base = -1;
124 
125 	ret = gpiochip_add(&tps6586x_gpio->gpio_chip);
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, tps6586x_gpio);
132 
133 	return ret;
134 }
135 
136 static int tps6586x_gpio_remove(struct platform_device *pdev)
137 {
138 	struct tps6586x_gpio *tps6586x_gpio = platform_get_drvdata(pdev);
139 
140 	gpiochip_remove(&tps6586x_gpio->gpio_chip);
141 	return 0;
142 }
143 
144 static struct platform_driver tps6586x_gpio_driver = {
145 	.driver.name	= "tps6586x-gpio",
146 	.driver.owner	= THIS_MODULE,
147 	.probe		= tps6586x_gpio_probe,
148 	.remove		= tps6586x_gpio_remove,
149 };
150 
151 static int __init tps6586x_gpio_init(void)
152 {
153 	return platform_driver_register(&tps6586x_gpio_driver);
154 }
155 subsys_initcall(tps6586x_gpio_init);
156 
157 static void __exit tps6586x_gpio_exit(void)
158 {
159 	platform_driver_unregister(&tps6586x_gpio_driver);
160 }
161 module_exit(tps6586x_gpio_exit);
162 
163 MODULE_ALIAS("platform:tps6586x-gpio");
164 MODULE_DESCRIPTION("GPIO interface for TPS6586X PMIC");
165 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
166 MODULE_LICENSE("GPL");
167