1/*
2 * TI Palma series PMIC's GPIO driver.
3 *
4 * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
5 *
6 * Author: Laxman Dewangan <ldewangan@nvidia.com>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms and conditions of the GNU General Public License,
10 * version 2, as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
15 * more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
19 */
20
21#include <linux/gpio.h>
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/mfd/palmas.h>
25#include <linux/of.h>
26#include <linux/of_device.h>
27#include <linux/platform_device.h>
28
29struct palmas_gpio {
30	struct gpio_chip gpio_chip;
31	struct palmas *palmas;
32};
33
34struct palmas_device_data {
35	int ngpio;
36};
37
38static inline struct palmas_gpio *to_palmas_gpio(struct gpio_chip *chip)
39{
40	return container_of(chip, struct palmas_gpio, gpio_chip);
41}
42
43static int palmas_gpio_get(struct gpio_chip *gc, unsigned offset)
44{
45	struct palmas_gpio *pg = to_palmas_gpio(gc);
46	struct palmas *palmas = pg->palmas;
47	unsigned int val;
48	int ret;
49	unsigned int reg;
50	int gpio16 = (offset/8);
51
52	offset %= 8;
53	reg = (gpio16) ? PALMAS_GPIO_DATA_DIR2 : PALMAS_GPIO_DATA_DIR;
54
55	ret = palmas_read(palmas, PALMAS_GPIO_BASE, reg, &val);
56	if (ret < 0) {
57		dev_err(gc->dev, "Reg 0x%02x read failed, %d\n", reg, ret);
58		return ret;
59	}
60
61	if (val & BIT(offset))
62		reg = (gpio16) ? PALMAS_GPIO_DATA_OUT2 : PALMAS_GPIO_DATA_OUT;
63	else
64		reg = (gpio16) ? PALMAS_GPIO_DATA_IN2 : PALMAS_GPIO_DATA_IN;
65
66	ret = palmas_read(palmas, PALMAS_GPIO_BASE, reg, &val);
67	if (ret < 0) {
68		dev_err(gc->dev, "Reg 0x%02x read failed, %d\n", reg, ret);
69		return ret;
70	}
71	return !!(val & BIT(offset));
72}
73
74static void palmas_gpio_set(struct gpio_chip *gc, unsigned offset,
75			int value)
76{
77	struct palmas_gpio *pg = to_palmas_gpio(gc);
78	struct palmas *palmas = pg->palmas;
79	int ret;
80	unsigned int reg;
81	int gpio16 = (offset/8);
82
83	offset %= 8;
84	if (gpio16)
85		reg = (value) ?
86			PALMAS_GPIO_SET_DATA_OUT2 : PALMAS_GPIO_CLEAR_DATA_OUT2;
87	else
88		reg = (value) ?
89			PALMAS_GPIO_SET_DATA_OUT : PALMAS_GPIO_CLEAR_DATA_OUT;
90
91	ret = palmas_write(palmas, PALMAS_GPIO_BASE, reg, BIT(offset));
92	if (ret < 0)
93		dev_err(gc->dev, "Reg 0x%02x write failed, %d\n", reg, ret);
94}
95
96static int palmas_gpio_output(struct gpio_chip *gc, unsigned offset,
97				int value)
98{
99	struct palmas_gpio *pg = to_palmas_gpio(gc);
100	struct palmas *palmas = pg->palmas;
101	int ret;
102	unsigned int reg;
103	int gpio16 = (offset/8);
104
105	offset %= 8;
106	reg = (gpio16) ? PALMAS_GPIO_DATA_DIR2 : PALMAS_GPIO_DATA_DIR;
107
108	/* Set the initial value */
109	palmas_gpio_set(gc, offset, value);
110
111	ret = palmas_update_bits(palmas, PALMAS_GPIO_BASE, reg,
112				BIT(offset), BIT(offset));
113	if (ret < 0)
114		dev_err(gc->dev, "Reg 0x%02x update failed, %d\n", reg, ret);
115	return ret;
116}
117
118static int palmas_gpio_input(struct gpio_chip *gc, unsigned offset)
119{
120	struct palmas_gpio *pg = to_palmas_gpio(gc);
121	struct palmas *palmas = pg->palmas;
122	int ret;
123	unsigned int reg;
124	int gpio16 = (offset/8);
125
126	offset %= 8;
127	reg = (gpio16) ? PALMAS_GPIO_DATA_DIR2 : PALMAS_GPIO_DATA_DIR;
128
129	ret = palmas_update_bits(palmas, PALMAS_GPIO_BASE, reg, BIT(offset), 0);
130	if (ret < 0)
131		dev_err(gc->dev, "Reg 0x%02x update failed, %d\n", reg, ret);
132	return ret;
133}
134
135static int palmas_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
136{
137	struct palmas_gpio *pg = to_palmas_gpio(gc);
138	struct palmas *palmas = pg->palmas;
139
140	return palmas_irq_get_virq(palmas, PALMAS_GPIO_0_IRQ + offset);
141}
142
143static const struct palmas_device_data palmas_dev_data = {
144	.ngpio = 8,
145};
146
147static const struct palmas_device_data tps80036_dev_data = {
148	.ngpio = 16,
149};
150
151static const struct of_device_id of_palmas_gpio_match[] = {
152	{ .compatible = "ti,palmas-gpio", .data = &palmas_dev_data,},
153	{ .compatible = "ti,tps65913-gpio", .data = &palmas_dev_data,},
154	{ .compatible = "ti,tps65914-gpio", .data = &palmas_dev_data,},
155	{ .compatible = "ti,tps80036-gpio", .data = &tps80036_dev_data,},
156	{ },
157};
158MODULE_DEVICE_TABLE(of, of_palmas_gpio_match);
159
160static int palmas_gpio_probe(struct platform_device *pdev)
161{
162	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
163	struct palmas_platform_data *palmas_pdata;
164	struct palmas_gpio *palmas_gpio;
165	int ret;
166	const struct of_device_id *match;
167	const struct palmas_device_data *dev_data;
168
169	match = of_match_device(of_palmas_gpio_match, &pdev->dev);
170	dev_data = match->data;
171	if (!dev_data)
172		dev_data = &palmas_dev_data;
173
174	palmas_gpio = devm_kzalloc(&pdev->dev,
175				sizeof(*palmas_gpio), GFP_KERNEL);
176	if (!palmas_gpio)
177		return -ENOMEM;
178
179	palmas_gpio->palmas = palmas;
180	palmas_gpio->gpio_chip.owner = THIS_MODULE;
181	palmas_gpio->gpio_chip.label = dev_name(&pdev->dev);
182	palmas_gpio->gpio_chip.ngpio = dev_data->ngpio;
183	palmas_gpio->gpio_chip.can_sleep = true;
184	palmas_gpio->gpio_chip.direction_input = palmas_gpio_input;
185	palmas_gpio->gpio_chip.direction_output = palmas_gpio_output;
186	palmas_gpio->gpio_chip.to_irq = palmas_gpio_to_irq;
187	palmas_gpio->gpio_chip.set	= palmas_gpio_set;
188	palmas_gpio->gpio_chip.get	= palmas_gpio_get;
189	palmas_gpio->gpio_chip.dev = &pdev->dev;
190#ifdef CONFIG_OF_GPIO
191	palmas_gpio->gpio_chip.of_node = pdev->dev.of_node;
192#endif
193	palmas_pdata = dev_get_platdata(palmas->dev);
194	if (palmas_pdata && palmas_pdata->gpio_base)
195		palmas_gpio->gpio_chip.base = palmas_pdata->gpio_base;
196	else
197		palmas_gpio->gpio_chip.base = -1;
198
199	ret = gpiochip_add(&palmas_gpio->gpio_chip);
200	if (ret < 0) {
201		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
202		return ret;
203	}
204
205	platform_set_drvdata(pdev, palmas_gpio);
206	return ret;
207}
208
209static int palmas_gpio_remove(struct platform_device *pdev)
210{
211	struct palmas_gpio *palmas_gpio = platform_get_drvdata(pdev);
212
213	gpiochip_remove(&palmas_gpio->gpio_chip);
214	return 0;
215}
216
217static struct platform_driver palmas_gpio_driver = {
218	.driver.name	= "palmas-gpio",
219	.driver.owner	= THIS_MODULE,
220	.driver.of_match_table = of_palmas_gpio_match,
221	.probe		= palmas_gpio_probe,
222	.remove		= palmas_gpio_remove,
223};
224
225static int __init palmas_gpio_init(void)
226{
227	return platform_driver_register(&palmas_gpio_driver);
228}
229subsys_initcall(palmas_gpio_init);
230
231static void __exit palmas_gpio_exit(void)
232{
233	platform_driver_unregister(&palmas_gpio_driver);
234}
235module_exit(palmas_gpio_exit);
236
237MODULE_ALIAS("platform:palmas-gpio");
238MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
239MODULE_DESCRIPTION("GPIO driver for TI Palmas series PMICs");
240MODULE_LICENSE("GPL v2");
241