atmel_spi: allow transfer when max_speed_hz = 0
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / gpio / pca953x.c
CommitLineData
9e60fdcf 1/*
f5e8ff48 2 * pca953x.c - 4/8/16 bit I/O ports
9e60fdcf 3 *
4 * Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com>
5 * Copyright (C) 2007 Marvell International Ltd.
6 *
7 * Derived from drivers/i2c/chips/pca9539.c
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; version 2 of the License.
12 */
13
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/i2c.h>
d1c057e3 17#include <linux/i2c/pca953x.h>
9e60fdcf 18
19#include <asm/gpio.h>
20
f5e8ff48
GL
21#define PCA953X_INPUT 0
22#define PCA953X_OUTPUT 1
23#define PCA953X_INVERT 2
24#define PCA953X_DIRECTION 3
9e60fdcf 25
3760f736 26static const struct i2c_device_id pca953x_id[] = {
f5e8ff48
GL
27 { "pca9534", 8, },
28 { "pca9535", 16, },
29 { "pca9536", 4, },
30 { "pca9537", 4, },
31 { "pca9538", 8, },
32 { "pca9539", 16, },
69292b34 33 { "pca9554", 8, },
f39e5781
WN
34 { "pca9555", 16, },
35 { "pca9557", 8, },
ab5dc372 36
7059d4b0 37 { "max7310", 8, },
ab5dc372
DB
38 { "pca6107", 8, },
39 { "tca6408", 8, },
40 { "tca6416", 16, },
41 /* NYET: { "tca6424", 24, }, */
3760f736 42 { }
f5e8ff48 43};
3760f736 44MODULE_DEVICE_TABLE(i2c, pca953x_id);
9e60fdcf 45
f3dc3630 46struct pca953x_chip {
9e60fdcf 47 unsigned gpio_start;
48 uint16_t reg_output;
49 uint16_t reg_direction;
50
51 struct i2c_client *client;
52 struct gpio_chip gpio_chip;
53};
54
f3dc3630 55static int pca953x_write_reg(struct pca953x_chip *chip, int reg, uint16_t val)
9e60fdcf 56{
f5e8ff48
GL
57 int ret;
58
59 if (chip->gpio_chip.ngpio <= 8)
60 ret = i2c_smbus_write_byte_data(chip->client, reg, val);
9e60fdcf 61 else
f5e8ff48
GL
62 ret = i2c_smbus_write_word_data(chip->client, reg << 1, val);
63
64 if (ret < 0) {
65 dev_err(&chip->client->dev, "failed writing register\n");
ab5dc372 66 return ret;
f5e8ff48
GL
67 }
68
69 return 0;
9e60fdcf 70}
71
f3dc3630 72static int pca953x_read_reg(struct pca953x_chip *chip, int reg, uint16_t *val)
9e60fdcf 73{
74 int ret;
75
f5e8ff48
GL
76 if (chip->gpio_chip.ngpio <= 8)
77 ret = i2c_smbus_read_byte_data(chip->client, reg);
78 else
79 ret = i2c_smbus_read_word_data(chip->client, reg << 1);
80
9e60fdcf 81 if (ret < 0) {
82 dev_err(&chip->client->dev, "failed reading register\n");
ab5dc372 83 return ret;
9e60fdcf 84 }
85
86 *val = (uint16_t)ret;
87 return 0;
88}
89
f3dc3630 90static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
9e60fdcf 91{
f3dc3630 92 struct pca953x_chip *chip;
9e60fdcf 93 uint16_t reg_val;
94 int ret;
95
f3dc3630 96 chip = container_of(gc, struct pca953x_chip, gpio_chip);
9e60fdcf 97
98 reg_val = chip->reg_direction | (1u << off);
f3dc3630 99 ret = pca953x_write_reg(chip, PCA953X_DIRECTION, reg_val);
9e60fdcf 100 if (ret)
101 return ret;
102
103 chip->reg_direction = reg_val;
104 return 0;
105}
106
f3dc3630 107static int pca953x_gpio_direction_output(struct gpio_chip *gc,
9e60fdcf 108 unsigned off, int val)
109{
f3dc3630 110 struct pca953x_chip *chip;
9e60fdcf 111 uint16_t reg_val;
112 int ret;
113
f3dc3630 114 chip = container_of(gc, struct pca953x_chip, gpio_chip);
9e60fdcf 115
116 /* set output level */
117 if (val)
118 reg_val = chip->reg_output | (1u << off);
119 else
120 reg_val = chip->reg_output & ~(1u << off);
121
f3dc3630 122 ret = pca953x_write_reg(chip, PCA953X_OUTPUT, reg_val);
9e60fdcf 123 if (ret)
124 return ret;
125
126 chip->reg_output = reg_val;
127
128 /* then direction */
129 reg_val = chip->reg_direction & ~(1u << off);
f3dc3630 130 ret = pca953x_write_reg(chip, PCA953X_DIRECTION, reg_val);
9e60fdcf 131 if (ret)
132 return ret;
133
134 chip->reg_direction = reg_val;
135 return 0;
136}
137
f3dc3630 138static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
9e60fdcf 139{
f3dc3630 140 struct pca953x_chip *chip;
9e60fdcf 141 uint16_t reg_val;
142 int ret;
143
f3dc3630 144 chip = container_of(gc, struct pca953x_chip, gpio_chip);
9e60fdcf 145
f3dc3630 146 ret = pca953x_read_reg(chip, PCA953X_INPUT, &reg_val);
9e60fdcf 147 if (ret < 0) {
148 /* NOTE: diagnostic already emitted; that's all we should
149 * do unless gpio_*_value_cansleep() calls become different
150 * from their nonsleeping siblings (and report faults).
151 */
152 return 0;
153 }
154
155 return (reg_val & (1u << off)) ? 1 : 0;
156}
157
f3dc3630 158static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
9e60fdcf 159{
f3dc3630 160 struct pca953x_chip *chip;
9e60fdcf 161 uint16_t reg_val;
162 int ret;
163
f3dc3630 164 chip = container_of(gc, struct pca953x_chip, gpio_chip);
9e60fdcf 165
166 if (val)
167 reg_val = chip->reg_output | (1u << off);
168 else
169 reg_val = chip->reg_output & ~(1u << off);
170
f3dc3630 171 ret = pca953x_write_reg(chip, PCA953X_OUTPUT, reg_val);
9e60fdcf 172 if (ret)
173 return;
174
175 chip->reg_output = reg_val;
176}
177
f5e8ff48 178static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
9e60fdcf 179{
180 struct gpio_chip *gc;
181
182 gc = &chip->gpio_chip;
183
f3dc3630
GL
184 gc->direction_input = pca953x_gpio_direction_input;
185 gc->direction_output = pca953x_gpio_direction_output;
186 gc->get = pca953x_gpio_get_value;
187 gc->set = pca953x_gpio_set_value;
84207805 188 gc->can_sleep = 1;
9e60fdcf 189
190 gc->base = chip->gpio_start;
f5e8ff48
GL
191 gc->ngpio = gpios;
192 gc->label = chip->client->name;
d8f388d8 193 gc->dev = &chip->client->dev;
d72cbed0 194 gc->owner = THIS_MODULE;
9e60fdcf 195}
196
d2653e92 197static int __devinit pca953x_probe(struct i2c_client *client,
3760f736 198 const struct i2c_device_id *id)
9e60fdcf 199{
f3dc3630
GL
200 struct pca953x_platform_data *pdata;
201 struct pca953x_chip *chip;
f39e5781 202 int ret;
9e60fdcf 203
204 pdata = client->dev.platform_data;
205 if (pdata == NULL)
206 return -ENODEV;
207
f3dc3630 208 chip = kzalloc(sizeof(struct pca953x_chip), GFP_KERNEL);
9e60fdcf 209 if (chip == NULL)
210 return -ENOMEM;
211
212 chip->client = client;
213
214 chip->gpio_start = pdata->gpio_base;
215
216 /* initialize cached registers from their original values.
217 * we can't share this chip with another i2c master.
218 */
f5e8ff48
GL
219 pca953x_setup_gpio(chip, id->driver_data);
220
f3dc3630 221 ret = pca953x_read_reg(chip, PCA953X_OUTPUT, &chip->reg_output);
9e60fdcf 222 if (ret)
223 goto out_failed;
224
f3dc3630 225 ret = pca953x_read_reg(chip, PCA953X_DIRECTION, &chip->reg_direction);
9e60fdcf 226 if (ret)
227 goto out_failed;
228
229 /* set platform specific polarity inversion */
f3dc3630 230 ret = pca953x_write_reg(chip, PCA953X_INVERT, pdata->invert);
9e60fdcf 231 if (ret)
232 goto out_failed;
233
f5e8ff48
GL
234
235 ret = gpiochip_add(&chip->gpio_chip);
9e60fdcf 236 if (ret)
237 goto out_failed;
238
239 if (pdata->setup) {
240 ret = pdata->setup(client, chip->gpio_chip.base,
241 chip->gpio_chip.ngpio, pdata->context);
242 if (ret < 0)
243 dev_warn(&client->dev, "setup failed, %d\n", ret);
244 }
245
246 i2c_set_clientdata(client, chip);
247 return 0;
248
249out_failed:
250 kfree(chip);
251 return ret;
252}
253
f3dc3630 254static int pca953x_remove(struct i2c_client *client)
9e60fdcf 255{
f3dc3630
GL
256 struct pca953x_platform_data *pdata = client->dev.platform_data;
257 struct pca953x_chip *chip = i2c_get_clientdata(client);
9e60fdcf 258 int ret = 0;
259
260 if (pdata->teardown) {
261 ret = pdata->teardown(client, chip->gpio_chip.base,
262 chip->gpio_chip.ngpio, pdata->context);
263 if (ret < 0) {
264 dev_err(&client->dev, "%s failed, %d\n",
265 "teardown", ret);
266 return ret;
267 }
268 }
269
270 ret = gpiochip_remove(&chip->gpio_chip);
271 if (ret) {
272 dev_err(&client->dev, "%s failed, %d\n",
273 "gpiochip_remove()", ret);
274 return ret;
275 }
276
277 kfree(chip);
278 return 0;
279}
280
f3dc3630 281static struct i2c_driver pca953x_driver = {
9e60fdcf 282 .driver = {
f3dc3630 283 .name = "pca953x",
9e60fdcf 284 },
f3dc3630
GL
285 .probe = pca953x_probe,
286 .remove = pca953x_remove,
3760f736 287 .id_table = pca953x_id,
9e60fdcf 288};
289
f3dc3630 290static int __init pca953x_init(void)
9e60fdcf 291{
f3dc3630 292 return i2c_add_driver(&pca953x_driver);
9e60fdcf 293}
2f8d1197
DB
294/* register after i2c postcore initcall and before
295 * subsys initcalls that may rely on these GPIOs
296 */
297subsys_initcall(pca953x_init);
9e60fdcf 298
f3dc3630 299static void __exit pca953x_exit(void)
9e60fdcf 300{
f3dc3630 301 i2c_del_driver(&pca953x_driver);
9e60fdcf 302}
f3dc3630 303module_exit(pca953x_exit);
9e60fdcf 304
305MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
f3dc3630 306MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
9e60fdcf 307MODULE_LICENSE("GPL");