mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-22 00:40:03 +00:00
![Maximilian Güntner](/assets/img/avatar_default.png)
The NXP PCA9685 supports 16 channels/leds using a 12-bit PWM (4095 levels of brightness) This driver supports configuration using platform_data. Signed-off-by: Maximilian Güntner <maximilian.guentner@gmail.com> Signed-off-by: Bryan Wu <cooloney@gmail.com>
213 lines
5.3 KiB
C
213 lines
5.3 KiB
C
/*
|
|
* Copyright 2013 Maximilian Güntner <maximilian.guentner@gmail.com>
|
|
*
|
|
* This file is subject to the terms and conditions of version 2 of
|
|
* the GNU General Public License. See the file COPYING in the main
|
|
* directory of this archive for more details.
|
|
*
|
|
* Based on leds-pca963x.c driver by
|
|
* Peter Meerwald <p.meerwald@bct-electronic.com>
|
|
*
|
|
* Driver for the NXP PCA9685 12-Bit PWM LED driver chip.
|
|
*
|
|
*/
|
|
|
|
#include <linux/ctype.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/err.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/leds.h>
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/string.h>
|
|
#include <linux/workqueue.h>
|
|
|
|
#include <linux/platform_data/leds-pca9685.h>
|
|
|
|
/* Register Addresses */
|
|
#define PCA9685_MODE1 0x00
|
|
#define PCA9685_MODE2 0x01
|
|
#define PCA9685_LED0_ON_L 0x06
|
|
#define PCA9685_ALL_LED_ON_L 0xFA
|
|
|
|
/* MODE1 Register */
|
|
#define PCA9685_ALLCALL 0x00
|
|
#define PCA9685_SLEEP 0x04
|
|
#define PCA9685_AI 0x05
|
|
|
|
/* MODE2 Register */
|
|
#define PCA9685_INVRT 0x04
|
|
#define PCA9685_OUTDRV 0x02
|
|
|
|
static const struct i2c_device_id pca9685_id[] = {
|
|
{ "pca9685", 0 },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, pca9685_id);
|
|
|
|
struct pca9685_led {
|
|
struct i2c_client *client;
|
|
struct work_struct work;
|
|
u16 brightness;
|
|
struct led_classdev led_cdev;
|
|
int led_num; /* 0-15 */
|
|
char name[32];
|
|
};
|
|
|
|
static void pca9685_write_msg(struct i2c_client *client, u8 *buf, u8 len)
|
|
{
|
|
struct i2c_msg msg = {
|
|
.addr = client->addr,
|
|
.flags = 0x00,
|
|
.len = len,
|
|
.buf = buf
|
|
};
|
|
i2c_transfer(client->adapter, &msg, 1);
|
|
}
|
|
|
|
static void pca9685_all_off(struct i2c_client *client)
|
|
{
|
|
u8 i2c_buffer[5] = {PCA9685_ALL_LED_ON_L, 0x00, 0x00, 0x00, 0x10};
|
|
pca9685_write_msg(client, i2c_buffer, 5);
|
|
}
|
|
|
|
static void pca9685_led_work(struct work_struct *work)
|
|
{
|
|
struct pca9685_led *pca9685;
|
|
u8 i2c_buffer[5];
|
|
|
|
pca9685 = container_of(work, struct pca9685_led, work);
|
|
i2c_buffer[0] = PCA9685_LED0_ON_L + 4 * pca9685->led_num;
|
|
/*
|
|
* 4095 is the maximum brightness, so we set the ON time to 0x1000
|
|
* which disables the PWM generator for that LED
|
|
*/
|
|
if (pca9685->brightness == 4095)
|
|
*((__le16 *)(i2c_buffer+1)) = cpu_to_le16(0x1000);
|
|
else
|
|
*((__le16 *)(i2c_buffer+1)) = 0x0000;
|
|
|
|
if (pca9685->brightness == 0)
|
|
*((__le16 *)(i2c_buffer+3)) = cpu_to_le16(0x1000);
|
|
else if (pca9685->brightness == 4095)
|
|
*((__le16 *)(i2c_buffer+3)) = 0x0000;
|
|
else
|
|
*((__le16 *)(i2c_buffer+3)) = cpu_to_le16(pca9685->brightness);
|
|
|
|
pca9685_write_msg(pca9685->client, i2c_buffer, 5);
|
|
}
|
|
|
|
static void pca9685_led_set(struct led_classdev *led_cdev,
|
|
enum led_brightness value)
|
|
{
|
|
struct pca9685_led *pca9685;
|
|
pca9685 = container_of(led_cdev, struct pca9685_led, led_cdev);
|
|
pca9685->brightness = value;
|
|
|
|
schedule_work(&pca9685->work);
|
|
}
|
|
|
|
static int pca9685_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct pca9685_led *pca9685;
|
|
struct pca9685_platform_data *pdata;
|
|
int err;
|
|
u8 i;
|
|
|
|
pdata = dev_get_platdata(&client->dev);
|
|
if (pdata) {
|
|
if (pdata->leds.num_leds < 1 || pdata->leds.num_leds > 15) {
|
|
dev_err(&client->dev, "board info must claim 1-16 LEDs");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
pca9685 = devm_kzalloc(&client->dev, 16 * sizeof(*pca9685), GFP_KERNEL);
|
|
if (!pca9685)
|
|
return -ENOMEM;
|
|
|
|
i2c_set_clientdata(client, pca9685);
|
|
pca9685_all_off(client);
|
|
|
|
for (i = 0; i < 16; i++) {
|
|
pca9685[i].client = client;
|
|
pca9685[i].led_num = i;
|
|
pca9685[i].name[0] = '\0';
|
|
if (pdata && i < pdata->leds.num_leds) {
|
|
if (pdata->leds.leds[i].name)
|
|
strncpy(pca9685[i].name,
|
|
pdata->leds.leds[i].name,
|
|
sizeof(pca9685[i].name)-1);
|
|
if (pdata->leds.leds[i].default_trigger)
|
|
pca9685[i].led_cdev.default_trigger =
|
|
pdata->leds.leds[i].default_trigger;
|
|
}
|
|
if (strlen(pca9685[i].name) == 0) {
|
|
/*
|
|
* Write adapter and address to the name as well.
|
|
* Otherwise multiple chips attached to one host would
|
|
* not work.
|
|
*/
|
|
snprintf(pca9685[i].name, sizeof(pca9685[i].name),
|
|
"pca9685:%d:x%.2x:%d",
|
|
client->adapter->nr, client->addr, i);
|
|
}
|
|
pca9685[i].led_cdev.name = pca9685[i].name;
|
|
pca9685[i].led_cdev.max_brightness = 0xfff;
|
|
pca9685[i].led_cdev.brightness_set = pca9685_led_set;
|
|
|
|
INIT_WORK(&pca9685[i].work, pca9685_led_work);
|
|
err = led_classdev_register(&client->dev, &pca9685[i].led_cdev);
|
|
if (err < 0)
|
|
goto exit;
|
|
}
|
|
|
|
if (pdata)
|
|
i2c_smbus_write_byte_data(client, PCA9685_MODE2,
|
|
pdata->outdrv << PCA9685_OUTDRV |
|
|
pdata->inverted << PCA9685_INVRT);
|
|
else
|
|
i2c_smbus_write_byte_data(client, PCA9685_MODE2,
|
|
PCA9685_TOTEM_POLE << PCA9685_OUTDRV);
|
|
/* Enable Auto-Increment, enable oscillator, ALLCALL/SUBADDR disabled */
|
|
i2c_smbus_write_byte_data(client, PCA9685_MODE1, BIT(PCA9685_AI));
|
|
|
|
return 0;
|
|
|
|
exit:
|
|
while (i--) {
|
|
led_classdev_unregister(&pca9685[i].led_cdev);
|
|
cancel_work_sync(&pca9685[i].work);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static int pca9685_remove(struct i2c_client *client)
|
|
{
|
|
struct pca9685_led *pca9685 = i2c_get_clientdata(client);
|
|
u8 i;
|
|
|
|
for (i = 0; i < 16; i++) {
|
|
led_classdev_unregister(&pca9685[i].led_cdev);
|
|
cancel_work_sync(&pca9685[i].work);
|
|
}
|
|
pca9685_all_off(client);
|
|
return 0;
|
|
}
|
|
|
|
static struct i2c_driver pca9685_driver = {
|
|
.driver = {
|
|
.name = "leds-pca9685",
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.probe = pca9685_probe,
|
|
.remove = pca9685_remove,
|
|
.id_table = pca9685_id,
|
|
};
|
|
|
|
module_i2c_driver(pca9685_driver);
|
|
|
|
MODULE_AUTHOR("Maximilian Güntner <maximilian.guentner@gmail.com>");
|
|
MODULE_DESCRIPTION("PCA9685 LED Driver");
|
|
MODULE_LICENSE("GPL v2");
|