leds: lm355x: rename devAttr to avoid CamelCase
[linux-3.10.git] / drivers / leds / leds-pca9633.c
1 /*
2  * Copyright 2011 bct electronic GmbH
3  *
4  * Author: Peter Meerwald <p.meerwald@bct-electronic.com>
5  *
6  * Based on leds-pca955x.c
7  *
8  * This file is subject to the terms and conditions of version 2 of
9  * the GNU General Public License.  See the file COPYING in the main
10  * directory of this archive for more details.
11  *
12  * LED driver for the PCA9633 I2C LED driver (7-bit slave address 0x62)
13  *
14  */
15
16 #include <linux/module.h>
17 #include <linux/delay.h>
18 #include <linux/string.h>
19 #include <linux/ctype.h>
20 #include <linux/leds.h>
21 #include <linux/err.h>
22 #include <linux/i2c.h>
23 #include <linux/workqueue.h>
24 #include <linux/slab.h>
25 #include <linux/platform_data/leds-pca9633.h>
26
27 /* LED select registers determine the source that drives LED outputs */
28 #define PCA9633_LED_OFF         0x0     /* LED driver off */
29 #define PCA9633_LED_ON          0x1     /* LED driver on */
30 #define PCA9633_LED_PWM         0x2     /* Controlled through PWM */
31 #define PCA9633_LED_GRP_PWM     0x3     /* Controlled through PWM/GRPPWM */
32
33 #define PCA9633_MODE1           0x00
34 #define PCA9633_MODE2           0x01
35 #define PCA9633_PWM_BASE        0x02
36 #define PCA9633_LEDOUT          0x08
37
38 static const struct i2c_device_id pca9633_id[] = {
39         { "pca9633", 0 },
40         { }
41 };
42 MODULE_DEVICE_TABLE(i2c, pca9633_id);
43
44 struct pca9633_led {
45         struct i2c_client *client;
46         struct work_struct work;
47         enum led_brightness brightness;
48         struct led_classdev led_cdev;
49         int led_num; /* 0 .. 3 potentially */
50         char name[32];
51 };
52
53 static void pca9633_led_work(struct work_struct *work)
54 {
55         struct pca9633_led *pca9633 = container_of(work,
56                 struct pca9633_led, work);
57         u8 ledout = i2c_smbus_read_byte_data(pca9633->client, PCA9633_LEDOUT);
58         int shift = 2 * pca9633->led_num;
59         u8 mask = 0x3 << shift;
60
61         switch (pca9633->brightness) {
62         case LED_FULL:
63                 i2c_smbus_write_byte_data(pca9633->client, PCA9633_LEDOUT,
64                         (ledout & ~mask) | (PCA9633_LED_ON << shift));
65                 break;
66         case LED_OFF:
67                 i2c_smbus_write_byte_data(pca9633->client, PCA9633_LEDOUT,
68                         ledout & ~mask);
69                 break;
70         default:
71                 i2c_smbus_write_byte_data(pca9633->client,
72                         PCA9633_PWM_BASE + pca9633->led_num,
73                         pca9633->brightness);
74                 i2c_smbus_write_byte_data(pca9633->client, PCA9633_LEDOUT,
75                         (ledout & ~mask) | (PCA9633_LED_PWM << shift));
76                 break;
77         }
78 }
79
80 static void pca9633_led_set(struct led_classdev *led_cdev,
81         enum led_brightness value)
82 {
83         struct pca9633_led *pca9633;
84
85         pca9633 = container_of(led_cdev, struct pca9633_led, led_cdev);
86
87         pca9633->brightness = value;
88
89         /*
90          * Must use workqueue for the actual I/O since I2C operations
91          * can sleep.
92          */
93         schedule_work(&pca9633->work);
94 }
95
96 static int pca9633_probe(struct i2c_client *client,
97                                         const struct i2c_device_id *id)
98 {
99         struct pca9633_led *pca9633;
100         struct pca9633_platform_data *pdata;
101         int i, err;
102
103         pdata = client->dev.platform_data;
104
105         if (pdata) {
106                 if (pdata->leds.num_leds <= 0 || pdata->leds.num_leds > 4) {
107                         dev_err(&client->dev, "board info must claim at most 4 LEDs");
108                         return -EINVAL;
109                 }
110         }
111
112         pca9633 = devm_kzalloc(&client->dev, 4 * sizeof(*pca9633), GFP_KERNEL);
113         if (!pca9633)
114                 return -ENOMEM;
115
116         i2c_set_clientdata(client, pca9633);
117
118         for (i = 0; i < 4; i++) {
119                 pca9633[i].client = client;
120                 pca9633[i].led_num = i;
121
122                 /* Platform data can specify LED names and default triggers */
123                 if (pdata && i < pdata->leds.num_leds) {
124                         if (pdata->leds.leds[i].name)
125                                 snprintf(pca9633[i].name,
126                                          sizeof(pca9633[i].name), "pca9633:%s",
127                                          pdata->leds.leds[i].name);
128                         if (pdata->leds.leds[i].default_trigger)
129                                 pca9633[i].led_cdev.default_trigger =
130                                         pdata->leds.leds[i].default_trigger;
131                 } else {
132                         snprintf(pca9633[i].name, sizeof(pca9633[i].name),
133                                  "pca9633:%d", i);
134                 }
135
136                 pca9633[i].led_cdev.name = pca9633[i].name;
137                 pca9633[i].led_cdev.brightness_set = pca9633_led_set;
138
139                 INIT_WORK(&pca9633[i].work, pca9633_led_work);
140
141                 err = led_classdev_register(&client->dev, &pca9633[i].led_cdev);
142                 if (err < 0)
143                         goto exit;
144         }
145
146         /* Disable LED all-call address and set normal mode */
147         i2c_smbus_write_byte_data(client, PCA9633_MODE1, 0x00);
148
149         /* Configure output: open-drain or totem pole (push-pull) */
150         if (pdata && pdata->outdrv == PCA9633_OPEN_DRAIN)
151                 i2c_smbus_write_byte_data(client, PCA9633_MODE2, 0x01);
152
153         /* Turn off LEDs */
154         i2c_smbus_write_byte_data(client, PCA9633_LEDOUT, 0x00);
155
156         return 0;
157
158 exit:
159         while (i--) {
160                 led_classdev_unregister(&pca9633[i].led_cdev);
161                 cancel_work_sync(&pca9633[i].work);
162         }
163
164         return err;
165 }
166
167 static int pca9633_remove(struct i2c_client *client)
168 {
169         struct pca9633_led *pca9633 = i2c_get_clientdata(client);
170         int i;
171
172         for (i = 0; i < 4; i++) {
173                 led_classdev_unregister(&pca9633[i].led_cdev);
174                 cancel_work_sync(&pca9633[i].work);
175         }
176
177         return 0;
178 }
179
180 static struct i2c_driver pca9633_driver = {
181         .driver = {
182                 .name   = "leds-pca9633",
183                 .owner  = THIS_MODULE,
184         },
185         .probe  = pca9633_probe,
186         .remove = pca9633_remove,
187         .id_table = pca9633_id,
188 };
189
190 module_i2c_driver(pca9633_driver);
191
192 MODULE_AUTHOR("Peter Meerwald <p.meerwald@bct-electronic.com>");
193 MODULE_DESCRIPTION("PCA9633 LED driver");
194 MODULE_LICENSE("GPL v2");