/*
* leds-blinkm.c
* (c) Jan-Simon Möller (dl9pf@gmx.de)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>
#include <linux/printk.h>
#include <linux/pm_runtime.h>
#include <linux/leds.h>
#include <linux/delay.h>
/* Addresses to scan - BlinkM is on 0x09 by default*/
static const unsigned short normal_i2c[] = { 0x09, I2C_CLIENT_END };
static int blinkm_transfer_hw(struct i2c_client *client, int cmd);
static int blinkm_test_run(struct i2c_client *client);
struct blinkm_led {
struct i2c_client *i2c_client;
struct led_classdev led_cdev;
int id;
atomic_t active;
};
struct blinkm_work {
struct blinkm_led *blinkm_led;
struct work_struct work;
};
#define cdev_to_blmled(c) container_of(c, struct blinkm_led, led_cdev)
#define work_to_blmwork(c) container_of(c, struct blinkm_work, work)
struct blinkm_data {
struct i2c_client *i2c_client;
struct mutex update_lock;
/* used for led class interface */
struct blinkm_led blinkm_leds[3];
/* used for "blinkm" sysfs interface */
u8 red; /* color red */
u8 green; /* color green */
u8 blue; /* color blue */
/* next values to use for transfer */
u8 next_red; /* color red */
u8 next_green; /* color green */
u8 next_blue; /* color blue */
/* internal use */
u8 args[7]; /* set of args for transmission */
u8 i2c_addr; /* i2c addr */
u8 fw_ver; /* firmware version */
/* used, but not from userspace */
u8 hue; /* HSB hue */
u8 saturation; /* HSB saturation */
u8 brightness; /* HSB brightness */
u8 next_hue; /* HSB hue */
u8 next_saturation; /* HSB saturation */
u8 next_brightness; /* HSB brightness */
/* currently unused / todo */
u8 fade_speed; /* fade speed 1 - 255 */
s8 time_adjust; /* time adjust -128 - 127 */
u8 fade:1; /* fade on = 1, off = 0 */
u8 rand:1; /* rand fade mode on = 1 */
u8 script_id; /* script ID */
u8 script_repeats; /* repeats of script */
u8 script_startline; /* line to start */
};
/* Colors */
#define RED 0
#define GREEN 1
#define BLUE 2
/* mapping command names to cmd chars - see datasheet */
#define BLM_GO_RGB 0
#define BLM_FADE_RGB 1
#define BLM_FADE_HSB 2
#define BLM_FADE_RAND_RGB 3
#define BLM_FADE_RAND_HSB 4
#define BLM_PLAY_SCRIPT 5
#define BLM_STOP_SCRIPT 6
#define BLM_SET_FADE_SPEED 7
#define BLM_SET_TIME_ADJ 8
#define BLM_GET_CUR_RGB 9
#define BLM_WRITE_SCRIPT_LINE 10
#define BLM_READ_SCRIPT_LINE 11
#define BLM_SET_SCRIPT_LR 12 /* Length & Repeats */
#define BLM_SET_ADDR 13
#define BLM_GET_ADDR 14
#define BLM_GET_FW_VER 15
#define BLM_SET_STARTUP_PARAM 16
/* BlinkM Commands
* as extracted out of the datasheet:
*
* cmdchar = command (ascii)
* cmdbyte = command in hex
* nr_args = number of arguments (to send)
* nr_ret = number of return values (to read)
* dir = direction (0 = read, 1 = write, 2 = both)
*
*/
static const struct {
char cmdchar;
u8 cmdbyte;
u8 nr_args;
u8 nr_ret;
u8 dir:2;
} blinkm_cmds[17] = {
/* cmdchar, cmdbyte, nr_args, nr_ret, dir */
{ 'n', 0x6e, 3, 0, 1},
{ 'c', 0x63, 3, 0, 1},
{ 'h', 0x68, 3, 0, 1},
{ 'C', 0x43, 3, 0, 1},
{ 'H', 0x48, 3, 0, 1},
{ 'p', 0x70, 3, 0, 1},
{ 'o', 0x6f, 0, 0, 1},
{ 'f', 0x66, 1, 0, 1},
{ 't', 0x74, 1, 0, 1},
{ 'g', 0x67, 0, 3, 0},
{ 'W', 0x57, 7, 0, 1},
{ 'R', 0x52, 2, 5, 2},
{ 'L', 0x4c, 3, 0, 1},
{ 'A', 0x41, 4, 0, 1},
{ 'a', 0x61, 0, 1, 0},
{ 'Z', 0x5a, 0, 1, 0},
{ 'B', 0x42, 5, 0, 1},
};
static ssize_t show_color_common(struct device *dev, char *buf, int color)
{
struct i2c_client *client;
struct blinkm_data *data;
int ret;
client = to_i2c_client(dev);
data = i2c_get_clientdata(client);
ret = blinkm_transfer_hw(client, BLM_GET_CUR_RGB);
if (ret < 0)
return ret;
switch (color) {
case RED:
return scnprintf(buf, PAGE_SIZE, "%02X\n", data->red);
case GREEN:
return scnprintf(buf, PAGE_SIZE, "%02X\n", data->green);
case BLUE:
return scnprintf(buf, PAGE_SIZE, "%02X\n", data->blue);
default:
return -EINVAL;
}
return -EINVAL;
}
static int store_color_common(struct device *dev, const char *buf, int color)
{
struct i2c_client *client;
struct blinkm_data *data;
int ret;
u8 value;
client = to_i2c_client(dev);
data = i2c_get_clientdata(client);
ret = kstrtou8(buf, 10, &value);
if (ret < 0) {
dev_err(dev, "BlinkM: value too large!\n");
return ret;
}
switch (color) {
case RED:
data->next_red = value;
break;
case GREEN:
data->next_green = value;
break;
case BLUE:
data->next_blue = value;
break;
default:
return -EINVAL;
}
dev_dbg(dev, "next_red = %d, next_green = %d, next_blue = %d\n",
data->next_red, data->next_green, data->next_blue);
/* if mode ... */
ret = blinkm_transfer_hw(client, BLM_GO_RGB);
if (ret < 0) {
dev_err(dev, "BlinkM: can't set RGB\n");
return ret;
}
return 0;
}
static ssize_t show_red(struct device *dev, struct device_attribute *attr,
char *buf)
{
return show_color_common(dev, buf, RED);
}
static ssize_t store_red(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
int ret;
ret = store_color_common(dev, buf, RED);
if (ret < 0)
return ret;
return count;
}
static DEVICE_ATTR(red, S_IRUGO | S_IWUSR, show_red, store_red);
static ssize_t show_green(struct device *dev, struct device_attribute *attr,
char *buf)
{
return show_color_common(dev, buf, GREEN);
}
static ssize_t store_green(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
int ret;
ret = store_color_common(dev, buf, GREEN);
if (ret < 0)
return ret;
return count;
}
static DEVICE_ATTR(green, S_IRUGO | S_IWUSR, show_green, store_green);
static ssize_t show_blue(struct device *dev, struct device_attribute *attr,
char *buf)
{
return show_color_common(dev, buf, BLUE);
}
static ssize_t store_blue(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
int ret;
ret = store_color_common(dev, buf, BLUE);
if (ret < 0)
return ret;
return count;
}
static DEVICE_ATTR(blue, S_IRUGO | S_IWUSR, show_blue, store_blue);
static ssize_t show_test(struct device *dev, struct device_attribute *attr,
char *buf)
{
return scnprintf(buf, PAGE_SIZE,
"#Write into test to start test sequence!#\n");
}
static ssize_t store_test(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct i2c_client *client;
int ret;
client = to_i2c_client(dev);
/*test */
ret = blinkm_test_run(client);
if (ret < 0)
return ret;
return count;
}
static DEVICE_ATTR(test, S_IRUGO | S_IWUSR, show_test, store_test);
/* TODO: HSB, fade, timeadj, script ... */
static struct attribute *blinkm_attrs[] = {
&dev_attr_red.attr,
&dev_attr_green.attr,
&dev_attr_blue.attr,
&dev_attr_test.attr,
NULL,
};
static struct attribute_group blinkm_group = {
.name = "blinkm",
.attrs = blinkm_attrs,
};
static int blinkm_write(struct i2c_client *client, int cmd, u8 *arg)
{
int result;
int i;
int arglen = blinkm_cmds[cmd].nr_args;
/* write out cmd to blinkm - always / default step */
result = i2c_smbus_write_byte(client, blinkm_cmds[cmd].cmdbyte);
if (result < 0)
return result;
/* no args to write out */
if (arglen == 0)
return 0;
for (i = 0; i < arglen; i++) {
/* repeat for arglen */
result = i2c_smbus_write_byte(client, arg[i]);
if (result < 0)
return result;
}
return 0;
}
static int blinkm_read(struct i2c_client *client, int cmd, u8 *arg)
{
int result;
int i;
int retlen = blinkm_cmds[cmd].nr_ret;
for (i = 0; i < retlen; i++) {
/* repeat for retlen */
result = i2c_smbus_read_byte(client);
if (result < 0)
return result;
arg[i] = result;
}
return 0;
}
static int blinkm_transfer_hw(struct i2c_client *client, int cmd)
{
/* the protocol is simple but non-standard:
* e.g. cmd 'g' (= 0x67) for "get device address"
* - which defaults to 0x09 - would be the sequence:
* a) write 0x67 to the device (byte write)
* b) read the value (0x09) back right after (byte read)
*
* Watch out for "unfinished" sequences (i.e. not enough reads
* or writes after a command. It will make the blinkM misbehave.
* Sequence is key here.
*/
/* args / return are in private data struct */
struct blinkm_data *data = i2c_get_clientdata(client);
/* We start hardware transfers which are not to be
* mixed with other commands. Aquire a lock now. */
if (mutex_lock_interruptible(&data->update_lock) < 0)
return -EAGAIN;
/* switch cmd - usually write before reads */
switch (cmd) {
case BLM_FADE_RAND_RGB:
case BLM_GO_RGB:
case BLM_FADE_RGB:
data->args[0] = data->next_red;
data->args[1] = data->next_green;
data->args[2] = data->next_blue;
blinkm_write(client, cmd, data->args);
data->red = data->args[0];
data->green = data->args[1];
data->blue = data->args[2];
break;
case BLM_FADE_HSB:
case BLM_FADE_RAND_HSB:
data->args[0] = data->next_hue;
data->args[1] = data->next_saturation;
data->args[2] = data->next_brightness;
blinkm_write(client, cmd, data->args);
data->hue = data->next_hue;
data->saturation = data->next_saturation;
data->brightness = data->next_brightness;
break;
case BLM_PLAY_SCRIPT:
data->args[0] = data->script_id;
data->args[1] = data->script_repeats;
data->args[2] = data->script_startline;
blinkm_write(client, cmd, data->args);
break;
case BLM_STOP_SCRIPT:
blinkm_write(client, cmd, NULL);
break;
case BLM_GET_CUR_RGB:
data->args[0] = data->red;
data->args[1] = data->green;
data->args[2] = data->blue;
blinkm_write(client, cmd, NULL);
blinkm_read(client, cmd, data->args);
data->red = data->args[0];
data->green = data->args[1];
data->blue = data->args[2];
break;
case BLM_GET_ADDR:
data->args[0] = data->i2c_addr;
blinkm_write(client, cmd, NULL);
blinkm_read(client, cmd, data->args);
data->i2c_addr = data->args[0];
break;
case BLM_SET_TIME_ADJ:
case BLM_SET_FADE_SPEED:
case BLM_READ_SCRIPT_LINE:
case BLM_WRITE_SCRIPT_LINE:
case BLM_SET_SCRIPT_LR:
case BLM_SET_ADDR:
case BLM_GET_FW_VER:
case BLM_SET_STARTUP_PARAM:
dev_err(&client->dev,
"BlinkM: cmd %d not implemented yet.\n", cmd);
break;
default:
dev_err(&client->dev, "BlinkM: unknown command %d\n", cmd);
mutex_unlock(&data->update_lock);
return -EINVAL;
} /* end switch(cmd) */
/* transfers done, unlock */
mutex_unlock(&data->update_lock);
return 0;
}
static void led_work(struct work_struct *work)
{
int ret;
struct blinkm_led *led;
struct blinkm_data *data;
struct blinkm_work *blm_work = work_to_blmwork(work);
led = blm_work->blinkm_led;
data = i2c_get_clientdata(led->i2c_client);
ret = blinkm_transfer_hw(led->i2c_client, BLM_GO_RGB);
atomic_dec(&led->active);
dev_dbg(&led->i2c_client->dev,
"# DONE # next_red = %d, next_green = %d,"
" next_blue = %d, active = %d\n",
data->next_red, data->next_green,
data->next_blue, atomic_read(&led->active));
kfree(blm_work);
}
static int blinkm_led_common_set(struct led_classdev *led_cdev,
enum led_brightness value, int color)
{
/* led_brightness is 0, 127 or 255 - we just use it here as-is */
struct blinkm_led *led = cdev_to_blmled(led_cdev);
struct blinkm_data *data = i2c_get_clientdata(led->i2c_client);
struct blinkm_work *bl_work;
switch (color) {
case RED:
/* bail out if there's no change */
if (data->next_red == (u8) value)
return 0;
/* we assume a quite fast sequence here ([off]->on->off)
* think of network led trigger - we cannot blink that fast, so
* in case we already have a off->on->off transition queued up,
* we refuse to queue up more.
* Revisit: fast-changing brightness. */
if (atomic_read(&led->active) > 1)
return 0;
data->next_red = (u8) value;
break;
case GREEN:
/* bail out if there's no change */
if (data->next_green == (u8) value)
return 0;
/* we assume a quite fast sequence here ([off]->on->off)
* Revisit: fast-changing brightness. */
if (atomic_read(&led->active) > 1)
return 0;
data->next_green = (u8) value;
break;
case BLUE:
/* bail out if there's no change */
if (data->next_blue == (u8) value)
return 0;
/* we assume a quite fast sequence here ([off]->on->off)
* Revisit: fast-changing brightness. */
if (atomic_read(&led->active) > 1)
return 0;
data->next_blue = (u8) value;
break;
default:
dev_err(&led->i2c_client->dev, "BlinkM: unknown color.\n");
return -EINVAL;
}
bl_work = kzalloc(sizeof(*bl_work), GFP_ATOMIC);
if (!bl_work)
return -ENOMEM;
atomic_inc(&led->active);
dev_dbg(&led->i2c_client->dev,
"#TO_SCHED# next_red = %d, next_green = %d,"
" next_blue = %d, active = %d\n",
data->next_red, data->next_green,
data->next_blue, atomic_read(&led->active));
/* a fresh work _item_ for each change */
bl_work->blinkm_led = led;
INIT_WORK(&bl_work->work, led_work);
/* queue work in own queue for easy sync on exit*/
schedule_work(&bl_work->work);
return 0;
}
static void blinkm_led_red_set(struct led_classdev *led_cdev,
enum led_brightness value)
{
blinkm_led_common_set(led_cdev, value, RED);
}
static void blinkm_led_green_set(struct led_classdev *led_cdev,
enum led_brightness value)
{
blinkm_led_common_set(led_cdev, value, GREEN);
}
static void blinkm_led_blue_set(struct led_classdev *led_cdev,
enum led_brightness value)
{
blinkm_led_common_set(led_cdev, value, BLUE);
}
static void blinkm_init_hw(struct i2c_client *client)
{
int ret;
ret = blinkm_transfer_hw(client, BLM_STOP_SCRIPT);
ret = blinkm_transfer_hw(client, BLM_GO_RGB);
}
static int blinkm_test_run(struct i2c_client *client)
{
int ret;
struct blinkm_data *data = i2c_get_clientdata(client);
data->next_red = 0x01;
data->next_green = 0x05;
data->next_blue = 0x10;
ret = blinkm_transfer_hw(client, BLM_GO_RGB);
if (ret < 0)
return ret;
msleep(2000);
data->next_red = 0x25;
data->next_green = 0x10;
data->next_blue = 0x31;
ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
if (ret < 0)
return ret;
msleep(2000);
data->next_hue = 0x50;
data->next_saturation = 0x10;
data->next_brightness = 0x20;
ret = blinkm_transfer_hw(client, BLM_FADE_HSB);
if (ret < 0)
return ret;
msleep(2000);
return 0;
}
/* Return 0 if detection is successful, -ENODEV otherwise */
static int blinkm_detect(struct i2c_client *client, struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
int ret;
int count = 99;
u8 tmpargs[7];
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
| I2C_FUNC_SMBUS_WORD_DATA
| I2C_FUNC_SMBUS_WRITE_BYTE))
return -ENODEV;
/* Now, we do the remaining detection. Simple for now. */
/* We might need more guards to protect other i2c slaves */
/* make sure the blinkM is balanced (read/writes) */
while (count > 0) {
ret = blinkm_write(client, BLM_GET_ADDR, NULL);
usleep_range(5000, 10000);
ret = blinkm_read(client, BLM_GET_ADDR, tmpargs);
usleep_range(5000, 10000);
if (tmpargs[0] == 0x09)
count = 0;
count--;
}
/* Step 1: Read BlinkM address back - cmd_char 'a' */
ret = blinkm_write(client, BLM_GET_ADDR, NULL);
if (ret < 0)
return ret;
usleep_range(20000, 30000); /* allow a small delay */
ret = blinkm_read(client, BLM_GET_ADDR, tmpargs);
if (ret < 0)
return ret;
if (tmpargs[0] != 0x09) {
dev_err(&client->dev, "enodev DEV ADDR = 0x%02X\n", tmpargs[0]);
return -ENODEV;
}
strlcpy(info->type, "blinkm", I2C_NAME_SIZE);
return 0;
}
static int blinkm_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct blinkm_data *data;
struct blinkm_led *led[3];
int err, i;
char blinkm_led_name[28];
data = devm_kzalloc(&client->dev,
sizeof(struct blinkm_data), GFP_KERNEL);
if (!data) {
err = -ENOMEM;
goto exit;
}
data->i2c_addr = 0x09;
data->i2c_addr = 0x08;
/* i2c addr - use fake addr of 0x08 initially (real is 0x09) */
data->fw_ver = 0xfe;
/* firmware version - use fake until we read real value
* (currently broken - BlinkM confused!) */
data->script_id = 0x01;
data->i2c_client = client;
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
/* Register sysfs hooks */
err = sysfs_create_group(&client->dev.kobj, &blinkm_group);
if (err < 0) {
dev_err(&client->dev, "couldn't register sysfs group\n");
goto exit;
}
for (i = 0; i < 3; i++) {
/* RED = 0, GREEN = 1, BLUE = 2 */
led[i] = &data->blinkm_leds[i];
led[i]->i2c_client = client;
led[i]->id = i;
led[i]->led_cdev.max_brightness = 255;
led[i]->led_cdev.flags = LED_CORE_SUSPENDRESUME;
atomic_set(&led[i]->active, 0);
switch (i) {
case RED:
snprintf(blinkm_led_name, sizeof(blinkm_led_name),
"blinkm-%d-%d-red",
client->adapter->nr,
client->addr);
led[i]->led_cdev.name = blinkm_led_name;
led[i]->led_cdev.brightness_set = blinkm_led_red_set;
err = led_classdev_register(&client->dev,
&led[i]->led_cdev);
if (err < 0) {
dev_err(&client->dev,
"couldn't register LED %s\n",
led[i]->led_cdev.name);
goto failred;
}
break;
case GREEN:
snprintf(blinkm_led_name, sizeof(blinkm_led_name),
"blinkm-%d-%d-green",
client->adapter->nr,
client->addr);
led[i]->led_cdev.name = blinkm_led_name;
led[i]->led_cdev.brightness_set = blinkm_led_green_set;
err = led_classdev_register(&client->dev,
&led[i]->led_cdev);
if (err < 0) {
dev_err(&client->dev,
"couldn't register LED %s\n",
led[i]->led_cdev.name);
goto failgreen;
}
break;
case BLUE:
snprintf(blinkm_led_name, sizeof(blinkm_led_name),
"blinkm-%d-%d-blue",
client->adapter->nr,
client->addr);
led[i]->led_cdev.name = blinkm_led_name;
led[i]->led_cdev.brightness_set = blinkm_led_blue_set;
err = led_classdev_register(&client->dev,
&led[i]->led_cdev);
if (err < 0) {
dev_err(&client->dev,
"couldn't register LED %s\n",
led[i]->led_cdev.name);
goto failblue;
}
break;
} /* end switch */
} /* end for */
/* Initialize the blinkm */
blinkm_init_hw(client);
return 0;
failblue:
led_classdev_unregister(&led[GREEN]->led_cdev);
failgreen:
led_classdev_unregister(&led[RED]->led_cdev);
failred:
sysfs_remove_group(&client->dev.kobj, &blinkm_group);
exit:
return err;
}
static int blinkm_remove(struct i2c_client *client)
{
struct blinkm_data *data = i2c_get_clientdata(client);
int ret = 0;
int i;
/* make sure no workqueue entries are pending */
for (i = 0; i < 3; i++) {
flush_scheduled_work();
led_classdev_unregister(&data->blinkm_leds[i].led_cdev);
}
/* reset rgb */
data->next_red = 0x00;
data->next_green = 0x00;
data->next_blue = 0x00;
ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
if (ret < 0)
dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
/* reset hsb */
data->next_hue = 0x00;
data->next_saturation = 0x00;
data->next_brightness = 0x00;
ret = blinkm_transfer_hw(client, BLM_FADE_HSB);
if (ret < 0)
dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
/* red fade to off */
data->next_red = 0xff;
ret = blinkm_transfer_hw(client, BLM_GO_RGB);
if (ret < 0)
dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
/* off */
data->next_red = 0x00;
ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
if (ret < 0)
dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");
sysfs_remove_group(&client->dev.kobj, &blinkm_group);
return 0;
}
static const struct i2c_device_id blinkm_id[] = {
{"blinkm", 0},
{}
};
MODULE_DEVICE_TABLE(i2c, blinkm_id);
/* This is the driver that will be inserted */
static struct i2c_driver blinkm_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "blinkm",
},
.probe = blinkm_probe,
.remove = blinkm_remove,
.id_table = blinkm_id,
.detect = blinkm_detect,
.address_list = normal_i2c,
};
module_i2c_driver(blinkm_driver);
MODULE_AUTHOR("Jan-Simon Moeller <dl9pf@gmx.de>");
MODULE_DESCRIPTION("BlinkM RGB LED driver");
MODULE_LICENSE("GPL");