xref: /openbmc/linux/drivers/gpio/gpio-tps6586x.c (revision 8730046c)
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/init.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 int tps6586x_gpio_get(struct gpio_chip *gc, unsigned offset)
42 {
43 	struct tps6586x_gpio *tps6586x_gpio = gpiochip_get_data(gc);
44 	uint8_t val;
45 	int ret;
46 
47 	ret = tps6586x_read(tps6586x_gpio->parent, TPS6586X_GPIOSET2, &val);
48 	if (ret)
49 		return ret;
50 
51 	return !!(val & (1 << offset));
52 }
53 
54 static void tps6586x_gpio_set(struct gpio_chip *gc, unsigned offset,
55 			      int value)
56 {
57 	struct tps6586x_gpio *tps6586x_gpio = gpiochip_get_data(gc);
58 
59 	tps6586x_update(tps6586x_gpio->parent, TPS6586X_GPIOSET2,
60 			value << offset, 1 << offset);
61 }
62 
63 static int tps6586x_gpio_output(struct gpio_chip *gc, unsigned offset,
64 				int value)
65 {
66 	struct tps6586x_gpio *tps6586x_gpio = gpiochip_get_data(gc);
67 	uint8_t val, mask;
68 
69 	tps6586x_gpio_set(gc, offset, value);
70 
71 	val = 0x1 << (offset * 2);
72 	mask = 0x3 << (offset * 2);
73 
74 	return tps6586x_update(tps6586x_gpio->parent, TPS6586X_GPIOSET1,
75 				val, mask);
76 }
77 
78 static int tps6586x_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
79 {
80 	struct tps6586x_gpio *tps6586x_gpio = gpiochip_get_data(gc);
81 
82 	return tps6586x_irq_get_virq(tps6586x_gpio->parent,
83 				TPS6586X_INT_PLDO_0 + offset);
84 }
85 
86 static int tps6586x_gpio_probe(struct platform_device *pdev)
87 {
88 	struct tps6586x_platform_data *pdata;
89 	struct tps6586x_gpio *tps6586x_gpio;
90 	int ret;
91 
92 	pdata = dev_get_platdata(pdev->dev.parent);
93 	tps6586x_gpio = devm_kzalloc(&pdev->dev,
94 				sizeof(*tps6586x_gpio), GFP_KERNEL);
95 	if (!tps6586x_gpio)
96 		return -ENOMEM;
97 
98 	tps6586x_gpio->parent = pdev->dev.parent;
99 
100 	tps6586x_gpio->gpio_chip.owner = THIS_MODULE;
101 	tps6586x_gpio->gpio_chip.label = pdev->name;
102 	tps6586x_gpio->gpio_chip.parent = &pdev->dev;
103 	tps6586x_gpio->gpio_chip.ngpio = 4;
104 	tps6586x_gpio->gpio_chip.can_sleep = true;
105 
106 	/* FIXME: add handling of GPIOs as dedicated inputs */
107 	tps6586x_gpio->gpio_chip.direction_output = tps6586x_gpio_output;
108 	tps6586x_gpio->gpio_chip.set	= tps6586x_gpio_set;
109 	tps6586x_gpio->gpio_chip.get	= tps6586x_gpio_get;
110 	tps6586x_gpio->gpio_chip.to_irq	= tps6586x_gpio_to_irq;
111 
112 #ifdef CONFIG_OF_GPIO
113 	tps6586x_gpio->gpio_chip.of_node = pdev->dev.parent->of_node;
114 #endif
115 	if (pdata && pdata->gpio_base)
116 		tps6586x_gpio->gpio_chip.base = pdata->gpio_base;
117 	else
118 		tps6586x_gpio->gpio_chip.base = -1;
119 
120 	ret = devm_gpiochip_add_data(&pdev->dev, &tps6586x_gpio->gpio_chip,
121 				     tps6586x_gpio);
122 	if (ret < 0) {
123 		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
124 		return ret;
125 	}
126 
127 	platform_set_drvdata(pdev, tps6586x_gpio);
128 
129 	return ret;
130 }
131 
132 static struct platform_driver tps6586x_gpio_driver = {
133 	.driver.name	= "tps6586x-gpio",
134 	.probe		= tps6586x_gpio_probe,
135 };
136 
137 static int __init tps6586x_gpio_init(void)
138 {
139 	return platform_driver_register(&tps6586x_gpio_driver);
140 }
141 subsys_initcall(tps6586x_gpio_init);
142