blob: 5a99e81d27843c8ce9e376684196b5daa253f90a [file] [log] [blame]
eric miao9e60fdc2008-02-04 22:28:26 -08001/*
Guennadi Liakhovetskif5e8ff42008-02-06 01:39:04 -08002 * pca953x.c - 4/8/16 bit I/O ports
eric miao9e60fdc2008-02-04 22:28:26 -08003 *
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>
Guennadi Liakhovetskid1c057e32008-02-06 01:39:02 -080017#include <linux/i2c/pca953x.h>
eric miao9e60fdc2008-02-04 22:28:26 -080018
19#include <asm/gpio.h>
20
Guennadi Liakhovetskif5e8ff42008-02-06 01:39:04 -080021#define PCA953X_INPUT 0
22#define PCA953X_OUTPUT 1
23#define PCA953X_INVERT 2
24#define PCA953X_DIRECTION 3
eric miao9e60fdc2008-02-04 22:28:26 -080025
Jean Delvare3760f732008-04-29 23:11:40 +020026static const struct i2c_device_id pca953x_id[] = {
Guennadi Liakhovetskif5e8ff42008-02-06 01:39:04 -080027 { "pca9534", 8, },
28 { "pca9535", 16, },
29 { "pca9536", 4, },
30 { "pca9537", 4, },
31 { "pca9538", 8, },
32 { "pca9539", 16, },
33 /* REVISIT several pca955x parts should work here too */
Jean Delvare3760f732008-04-29 23:11:40 +020034 { }
Guennadi Liakhovetskif5e8ff42008-02-06 01:39:04 -080035};
Jean Delvare3760f732008-04-29 23:11:40 +020036MODULE_DEVICE_TABLE(i2c, pca953x_id);
eric miao9e60fdc2008-02-04 22:28:26 -080037
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -080038struct pca953x_chip {
eric miao9e60fdc2008-02-04 22:28:26 -080039 unsigned gpio_start;
40 uint16_t reg_output;
41 uint16_t reg_direction;
42
43 struct i2c_client *client;
44 struct gpio_chip gpio_chip;
45};
46
47/* NOTE: we can't currently rely on fault codes to come from SMBus
48 * calls, so we map all errors to EIO here and return zero otherwise.
49 */
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -080050static int pca953x_write_reg(struct pca953x_chip *chip, int reg, uint16_t val)
eric miao9e60fdc2008-02-04 22:28:26 -080051{
Guennadi Liakhovetskif5e8ff42008-02-06 01:39:04 -080052 int ret;
53
54 if (chip->gpio_chip.ngpio <= 8)
55 ret = i2c_smbus_write_byte_data(chip->client, reg, val);
eric miao9e60fdc2008-02-04 22:28:26 -080056 else
Guennadi Liakhovetskif5e8ff42008-02-06 01:39:04 -080057 ret = i2c_smbus_write_word_data(chip->client, reg << 1, val);
58
59 if (ret < 0) {
60 dev_err(&chip->client->dev, "failed writing register\n");
61 return -EIO;
62 }
63
64 return 0;
eric miao9e60fdc2008-02-04 22:28:26 -080065}
66
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -080067static int pca953x_read_reg(struct pca953x_chip *chip, int reg, uint16_t *val)
eric miao9e60fdc2008-02-04 22:28:26 -080068{
69 int ret;
70
Guennadi Liakhovetskif5e8ff42008-02-06 01:39:04 -080071 if (chip->gpio_chip.ngpio <= 8)
72 ret = i2c_smbus_read_byte_data(chip->client, reg);
73 else
74 ret = i2c_smbus_read_word_data(chip->client, reg << 1);
75
eric miao9e60fdc2008-02-04 22:28:26 -080076 if (ret < 0) {
77 dev_err(&chip->client->dev, "failed reading register\n");
78 return -EIO;
79 }
80
81 *val = (uint16_t)ret;
82 return 0;
83}
84
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -080085static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
eric miao9e60fdc2008-02-04 22:28:26 -080086{
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -080087 struct pca953x_chip *chip;
eric miao9e60fdc2008-02-04 22:28:26 -080088 uint16_t reg_val;
89 int ret;
90
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -080091 chip = container_of(gc, struct pca953x_chip, gpio_chip);
eric miao9e60fdc2008-02-04 22:28:26 -080092
93 reg_val = chip->reg_direction | (1u << off);
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -080094 ret = pca953x_write_reg(chip, PCA953X_DIRECTION, reg_val);
eric miao9e60fdc2008-02-04 22:28:26 -080095 if (ret)
96 return ret;
97
98 chip->reg_direction = reg_val;
99 return 0;
100}
101
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800102static int pca953x_gpio_direction_output(struct gpio_chip *gc,
eric miao9e60fdc2008-02-04 22:28:26 -0800103 unsigned off, int val)
104{
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800105 struct pca953x_chip *chip;
eric miao9e60fdc2008-02-04 22:28:26 -0800106 uint16_t reg_val;
107 int ret;
108
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800109 chip = container_of(gc, struct pca953x_chip, gpio_chip);
eric miao9e60fdc2008-02-04 22:28:26 -0800110
111 /* set output level */
112 if (val)
113 reg_val = chip->reg_output | (1u << off);
114 else
115 reg_val = chip->reg_output & ~(1u << off);
116
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800117 ret = pca953x_write_reg(chip, PCA953X_OUTPUT, reg_val);
eric miao9e60fdc2008-02-04 22:28:26 -0800118 if (ret)
119 return ret;
120
121 chip->reg_output = reg_val;
122
123 /* then direction */
124 reg_val = chip->reg_direction & ~(1u << off);
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800125 ret = pca953x_write_reg(chip, PCA953X_DIRECTION, reg_val);
eric miao9e60fdc2008-02-04 22:28:26 -0800126 if (ret)
127 return ret;
128
129 chip->reg_direction = reg_val;
130 return 0;
131}
132
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800133static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
eric miao9e60fdc2008-02-04 22:28:26 -0800134{
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800135 struct pca953x_chip *chip;
eric miao9e60fdc2008-02-04 22:28:26 -0800136 uint16_t reg_val;
137 int ret;
138
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800139 chip = container_of(gc, struct pca953x_chip, gpio_chip);
eric miao9e60fdc2008-02-04 22:28:26 -0800140
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800141 ret = pca953x_read_reg(chip, PCA953X_INPUT, &reg_val);
eric miao9e60fdc2008-02-04 22:28:26 -0800142 if (ret < 0) {
143 /* NOTE: diagnostic already emitted; that's all we should
144 * do unless gpio_*_value_cansleep() calls become different
145 * from their nonsleeping siblings (and report faults).
146 */
147 return 0;
148 }
149
150 return (reg_val & (1u << off)) ? 1 : 0;
151}
152
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800153static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
eric miao9e60fdc2008-02-04 22:28:26 -0800154{
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800155 struct pca953x_chip *chip;
eric miao9e60fdc2008-02-04 22:28:26 -0800156 uint16_t reg_val;
157 int ret;
158
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800159 chip = container_of(gc, struct pca953x_chip, gpio_chip);
eric miao9e60fdc2008-02-04 22:28:26 -0800160
161 if (val)
162 reg_val = chip->reg_output | (1u << off);
163 else
164 reg_val = chip->reg_output & ~(1u << off);
165
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800166 ret = pca953x_write_reg(chip, PCA953X_OUTPUT, reg_val);
eric miao9e60fdc2008-02-04 22:28:26 -0800167 if (ret)
168 return;
169
170 chip->reg_output = reg_val;
171}
172
Guennadi Liakhovetskif5e8ff42008-02-06 01:39:04 -0800173static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
eric miao9e60fdc2008-02-04 22:28:26 -0800174{
175 struct gpio_chip *gc;
176
177 gc = &chip->gpio_chip;
178
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800179 gc->direction_input = pca953x_gpio_direction_input;
180 gc->direction_output = pca953x_gpio_direction_output;
181 gc->get = pca953x_gpio_get_value;
182 gc->set = pca953x_gpio_set_value;
Arnaud Patard84207802008-03-10 11:43:48 -0700183 gc->can_sleep = 1;
eric miao9e60fdc2008-02-04 22:28:26 -0800184
185 gc->base = chip->gpio_start;
Guennadi Liakhovetskif5e8ff42008-02-06 01:39:04 -0800186 gc->ngpio = gpios;
187 gc->label = chip->client->name;
Guennadi Liakhovetskid72cbed2008-04-28 02:14:45 -0700188 gc->owner = THIS_MODULE;
eric miao9e60fdc2008-02-04 22:28:26 -0800189}
190
Jean Delvared2653e92008-04-29 23:11:39 +0200191static int __devinit pca953x_probe(struct i2c_client *client,
Jean Delvare3760f732008-04-29 23:11:40 +0200192 const struct i2c_device_id *id)
eric miao9e60fdc2008-02-04 22:28:26 -0800193{
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800194 struct pca953x_platform_data *pdata;
195 struct pca953x_chip *chip;
Guennadi Liakhovetskif5e8ff42008-02-06 01:39:04 -0800196 int ret, i;
eric miao9e60fdc2008-02-04 22:28:26 -0800197
198 pdata = client->dev.platform_data;
199 if (pdata == NULL)
200 return -ENODEV;
201
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800202 chip = kzalloc(sizeof(struct pca953x_chip), GFP_KERNEL);
eric miao9e60fdc2008-02-04 22:28:26 -0800203 if (chip == NULL)
204 return -ENOMEM;
205
206 chip->client = client;
207
208 chip->gpio_start = pdata->gpio_base;
209
210 /* initialize cached registers from their original values.
211 * we can't share this chip with another i2c master.
212 */
Guennadi Liakhovetskif5e8ff42008-02-06 01:39:04 -0800213 pca953x_setup_gpio(chip, id->driver_data);
214
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800215 ret = pca953x_read_reg(chip, PCA953X_OUTPUT, &chip->reg_output);
eric miao9e60fdc2008-02-04 22:28:26 -0800216 if (ret)
217 goto out_failed;
218
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800219 ret = pca953x_read_reg(chip, PCA953X_DIRECTION, &chip->reg_direction);
eric miao9e60fdc2008-02-04 22:28:26 -0800220 if (ret)
221 goto out_failed;
222
223 /* set platform specific polarity inversion */
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800224 ret = pca953x_write_reg(chip, PCA953X_INVERT, pdata->invert);
eric miao9e60fdc2008-02-04 22:28:26 -0800225 if (ret)
226 goto out_failed;
227
Guennadi Liakhovetskif5e8ff42008-02-06 01:39:04 -0800228
229 ret = gpiochip_add(&chip->gpio_chip);
eric miao9e60fdc2008-02-04 22:28:26 -0800230 if (ret)
231 goto out_failed;
232
233 if (pdata->setup) {
234 ret = pdata->setup(client, chip->gpio_chip.base,
235 chip->gpio_chip.ngpio, pdata->context);
236 if (ret < 0)
237 dev_warn(&client->dev, "setup failed, %d\n", ret);
238 }
239
240 i2c_set_clientdata(client, chip);
241 return 0;
242
243out_failed:
244 kfree(chip);
245 return ret;
246}
247
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800248static int pca953x_remove(struct i2c_client *client)
eric miao9e60fdc2008-02-04 22:28:26 -0800249{
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800250 struct pca953x_platform_data *pdata = client->dev.platform_data;
251 struct pca953x_chip *chip = i2c_get_clientdata(client);
eric miao9e60fdc2008-02-04 22:28:26 -0800252 int ret = 0;
253
254 if (pdata->teardown) {
255 ret = pdata->teardown(client, chip->gpio_chip.base,
256 chip->gpio_chip.ngpio, pdata->context);
257 if (ret < 0) {
258 dev_err(&client->dev, "%s failed, %d\n",
259 "teardown", ret);
260 return ret;
261 }
262 }
263
264 ret = gpiochip_remove(&chip->gpio_chip);
265 if (ret) {
266 dev_err(&client->dev, "%s failed, %d\n",
267 "gpiochip_remove()", ret);
268 return ret;
269 }
270
271 kfree(chip);
272 return 0;
273}
274
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800275static struct i2c_driver pca953x_driver = {
eric miao9e60fdc2008-02-04 22:28:26 -0800276 .driver = {
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800277 .name = "pca953x",
eric miao9e60fdc2008-02-04 22:28:26 -0800278 },
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800279 .probe = pca953x_probe,
280 .remove = pca953x_remove,
Jean Delvare3760f732008-04-29 23:11:40 +0200281 .id_table = pca953x_id,
eric miao9e60fdc2008-02-04 22:28:26 -0800282};
283
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800284static int __init pca953x_init(void)
eric miao9e60fdc2008-02-04 22:28:26 -0800285{
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800286 return i2c_add_driver(&pca953x_driver);
eric miao9e60fdc2008-02-04 22:28:26 -0800287}
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800288module_init(pca953x_init);
eric miao9e60fdc2008-02-04 22:28:26 -0800289
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800290static void __exit pca953x_exit(void)
eric miao9e60fdc2008-02-04 22:28:26 -0800291{
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800292 i2c_del_driver(&pca953x_driver);
eric miao9e60fdc2008-02-04 22:28:26 -0800293}
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800294module_exit(pca953x_exit);
eric miao9e60fdc2008-02-04 22:28:26 -0800295
296MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
Guennadi Liakhovetskif3dc3632008-02-06 01:39:03 -0800297MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
eric miao9e60fdc2008-02-04 22:28:26 -0800298MODULE_LICENSE("GPL");