mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 01:10:04 +00:00
316 lines
7.1 KiB
C
316 lines
7.1 KiB
C
![]() |
// SPDX-License-Identifier: GPL-2.0
|
||
|
// Copyright (c) 2018 Crane Merchandising Systems. All rights reserved.
|
||
|
// Copyright (C) 2018 Oleh Kravchenko <oleg@kaa.org.ua>
|
||
|
|
||
|
#include <linux/delay.h>
|
||
|
#include <linux/leds.h>
|
||
|
#include <linux/module.h>
|
||
|
#include <linux/of_device.h>
|
||
|
#include <linux/spi/spi.h>
|
||
|
#include <linux/workqueue.h>
|
||
|
#include <uapi/linux/uleds.h>
|
||
|
|
||
|
/*
|
||
|
* CR0014114 SPI protocol descrtiption:
|
||
|
* +----+-----------------------------------+----+
|
||
|
* | CMD| BRIGHTNESS |CRC |
|
||
|
* +----+-----------------------------------+----+
|
||
|
* | | LED0| LED1| LED2| LED3| LED4| LED5| |
|
||
|
* | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
|
||
|
* | |R|G|B|R|G|B|R|G|B|R|G|B|R|G|B|R|G|B| |
|
||
|
* | 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1 |
|
||
|
* | |1|1|1|1|1|1|1|1|1|1|1|1|1|1|1|1|1|1| |
|
||
|
* | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
|
||
|
* | | 18 | |
|
||
|
* +----+-----------------------------------+----+
|
||
|
* | 20 |
|
||
|
* +---------------------------------------------+
|
||
|
*
|
||
|
* PS: Boards can be connected to the chain:
|
||
|
* SPI -> board0 -> board1 -> board2 ..
|
||
|
*/
|
||
|
|
||
|
/* CR0014114 SPI commands */
|
||
|
#define CR_SET_BRIGHTNESS 0x80
|
||
|
#define CR_INIT_REENUMERATE 0x81
|
||
|
#define CR_NEXT_REENUMERATE 0x82
|
||
|
|
||
|
/* CR0014114 default settings */
|
||
|
#define CR_MAX_BRIGHTNESS GENMASK(6, 0)
|
||
|
#define CR_FW_DELAY_MSEC 10
|
||
|
#define CR_RECOUNT_DELAY (HZ * 3600)
|
||
|
|
||
|
struct cr0014114_led {
|
||
|
char name[LED_MAX_NAME_SIZE];
|
||
|
struct cr0014114 *priv;
|
||
|
struct led_classdev ldev;
|
||
|
u8 brightness;
|
||
|
};
|
||
|
|
||
|
struct cr0014114 {
|
||
|
bool do_recount;
|
||
|
size_t count;
|
||
|
struct delayed_work work;
|
||
|
struct device *dev;
|
||
|
struct mutex lock;
|
||
|
struct spi_device *spi;
|
||
|
u8 *buf;
|
||
|
unsigned long delay;
|
||
|
struct cr0014114_led leds[];
|
||
|
};
|
||
|
|
||
|
static void cr0014114_calc_crc(u8 *buf, const size_t len)
|
||
|
{
|
||
|
size_t i;
|
||
|
u8 crc;
|
||
|
|
||
|
for (i = 1, crc = 1; i < len - 1; i++)
|
||
|
crc += buf[i];
|
||
|
crc |= BIT(7);
|
||
|
|
||
|
/* special case when CRC matches the SPI commands */
|
||
|
if (crc == CR_SET_BRIGHTNESS ||
|
||
|
crc == CR_INIT_REENUMERATE ||
|
||
|
crc == CR_NEXT_REENUMERATE)
|
||
|
crc = 0xfe;
|
||
|
|
||
|
buf[len - 1] = crc;
|
||
|
}
|
||
|
|
||
|
static int cr0014114_recount(struct cr0014114 *priv)
|
||
|
{
|
||
|
int ret;
|
||
|
size_t i;
|
||
|
u8 cmd;
|
||
|
|
||
|
dev_dbg(priv->dev, "LEDs recount is started\n");
|
||
|
|
||
|
cmd = CR_INIT_REENUMERATE;
|
||
|
ret = spi_write(priv->spi, &cmd, sizeof(cmd));
|
||
|
if (ret)
|
||
|
goto err;
|
||
|
|
||
|
cmd = CR_NEXT_REENUMERATE;
|
||
|
for (i = 0; i < priv->count; i++) {
|
||
|
msleep(CR_FW_DELAY_MSEC);
|
||
|
|
||
|
ret = spi_write(priv->spi, &cmd, sizeof(cmd));
|
||
|
if (ret)
|
||
|
goto err;
|
||
|
}
|
||
|
|
||
|
err:
|
||
|
dev_dbg(priv->dev, "LEDs recount is finished\n");
|
||
|
|
||
|
if (ret)
|
||
|
dev_err(priv->dev, "with error %d", ret);
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static int cr0014114_sync(struct cr0014114 *priv)
|
||
|
{
|
||
|
int ret;
|
||
|
size_t i;
|
||
|
unsigned long udelay, now = jiffies;
|
||
|
|
||
|
/* to avoid SPI mistiming with firmware we should wait some time */
|
||
|
if (time_after(priv->delay, now)) {
|
||
|
udelay = jiffies_to_usecs(priv->delay - now);
|
||
|
usleep_range(udelay, udelay + 1);
|
||
|
}
|
||
|
|
||
|
if (unlikely(priv->do_recount)) {
|
||
|
ret = cr0014114_recount(priv);
|
||
|
if (ret)
|
||
|
goto err;
|
||
|
|
||
|
priv->do_recount = false;
|
||
|
msleep(CR_FW_DELAY_MSEC);
|
||
|
}
|
||
|
|
||
|
priv->buf[0] = CR_SET_BRIGHTNESS;
|
||
|
for (i = 0; i < priv->count; i++)
|
||
|
priv->buf[i + 1] = priv->leds[i].brightness;
|
||
|
cr0014114_calc_crc(priv->buf, priv->count + 2);
|
||
|
ret = spi_write(priv->spi, priv->buf, priv->count + 2);
|
||
|
|
||
|
err:
|
||
|
priv->delay = jiffies + msecs_to_jiffies(CR_FW_DELAY_MSEC);
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static void cr0014114_recount_work(struct work_struct *work)
|
||
|
{
|
||
|
int ret;
|
||
|
struct cr0014114 *priv = container_of(work,
|
||
|
struct cr0014114,
|
||
|
work.work);
|
||
|
|
||
|
mutex_lock(&priv->lock);
|
||
|
priv->do_recount = true;
|
||
|
ret = cr0014114_sync(priv);
|
||
|
mutex_unlock(&priv->lock);
|
||
|
|
||
|
if (ret)
|
||
|
dev_warn(priv->dev, "sync of LEDs failed %d\n", ret);
|
||
|
|
||
|
schedule_delayed_work(&priv->work, CR_RECOUNT_DELAY);
|
||
|
}
|
||
|
|
||
|
static int cr0014114_set_sync(struct led_classdev *ldev,
|
||
|
enum led_brightness brightness)
|
||
|
{
|
||
|
int ret;
|
||
|
struct cr0014114_led *led = container_of(ldev,
|
||
|
struct cr0014114_led,
|
||
|
ldev);
|
||
|
|
||
|
dev_dbg(led->priv->dev, "Set brightness of %s to %d\n",
|
||
|
led->name, brightness);
|
||
|
|
||
|
mutex_lock(&led->priv->lock);
|
||
|
led->brightness = (u8)brightness;
|
||
|
ret = cr0014114_sync(led->priv);
|
||
|
mutex_unlock(&led->priv->lock);
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static int cr0014114_probe_dt(struct cr0014114 *priv)
|
||
|
{
|
||
|
size_t i = 0;
|
||
|
struct cr0014114_led *led;
|
||
|
struct fwnode_handle *child;
|
||
|
struct device_node *np;
|
||
|
int ret;
|
||
|
const char *str;
|
||
|
|
||
|
device_for_each_child_node(priv->dev, child) {
|
||
|
np = to_of_node(child);
|
||
|
led = &priv->leds[i];
|
||
|
|
||
|
ret = fwnode_property_read_string(child, "label", &str);
|
||
|
if (ret)
|
||
|
snprintf(led->name, sizeof(led->name),
|
||
|
"cr0014114::");
|
||
|
else
|
||
|
snprintf(led->name, sizeof(led->name),
|
||
|
"cr0014114:%s", str);
|
||
|
|
||
|
fwnode_property_read_string(child, "linux,default-trigger",
|
||
|
&led->ldev.default_trigger);
|
||
|
|
||
|
led->priv = priv;
|
||
|
led->ldev.name = led->name;
|
||
|
led->ldev.max_brightness = CR_MAX_BRIGHTNESS;
|
||
|
led->ldev.brightness_set_blocking = cr0014114_set_sync;
|
||
|
|
||
|
ret = devm_of_led_classdev_register(priv->dev, np,
|
||
|
&led->ldev);
|
||
|
if (ret) {
|
||
|
dev_err(priv->dev,
|
||
|
"failed to register LED device %s, err %d",
|
||
|
led->name, ret);
|
||
|
fwnode_handle_put(child);
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
led->ldev.dev->of_node = np;
|
||
|
|
||
|
i++;
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int cr0014114_probe(struct spi_device *spi)
|
||
|
{
|
||
|
struct cr0014114 *priv;
|
||
|
size_t count;
|
||
|
int ret;
|
||
|
|
||
|
count = device_get_child_node_count(&spi->dev);
|
||
|
if (!count) {
|
||
|
dev_err(&spi->dev, "LEDs are not defined in device tree!");
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
|
||
|
priv = devm_kzalloc(&spi->dev,
|
||
|
sizeof(*priv) + sizeof(*priv->leds) * count,
|
||
|
GFP_KERNEL);
|
||
|
if (!priv)
|
||
|
return -ENOMEM;
|
||
|
|
||
|
priv->buf = devm_kzalloc(&spi->dev, count + 2, GFP_KERNEL);
|
||
|
if (!priv->buf)
|
||
|
return -ENOMEM;
|
||
|
|
||
|
mutex_init(&priv->lock);
|
||
|
INIT_DELAYED_WORK(&priv->work, cr0014114_recount_work);
|
||
|
priv->count = count;
|
||
|
priv->dev = &spi->dev;
|
||
|
priv->spi = spi;
|
||
|
priv->delay = jiffies -
|
||
|
msecs_to_jiffies(CR_FW_DELAY_MSEC);
|
||
|
|
||
|
priv->do_recount = true;
|
||
|
ret = cr0014114_sync(priv);
|
||
|
if (ret) {
|
||
|
dev_err(priv->dev, "first recount failed %d\n", ret);
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
priv->do_recount = true;
|
||
|
ret = cr0014114_sync(priv);
|
||
|
if (ret) {
|
||
|
dev_err(priv->dev, "second recount failed %d\n", ret);
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
ret = cr0014114_probe_dt(priv);
|
||
|
if (ret)
|
||
|
return ret;
|
||
|
|
||
|
/* setup recount work to workaround buggy firmware */
|
||
|
schedule_delayed_work(&priv->work, CR_RECOUNT_DELAY);
|
||
|
|
||
|
spi_set_drvdata(spi, priv);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int cr0014114_remove(struct spi_device *spi)
|
||
|
{
|
||
|
struct cr0014114 *priv = spi_get_drvdata(spi);
|
||
|
|
||
|
cancel_delayed_work_sync(&priv->work);
|
||
|
mutex_destroy(&priv->lock);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static const struct of_device_id cr0014114_dt_ids[] = {
|
||
|
{ .compatible = "crane,cr0014114", },
|
||
|
{},
|
||
|
};
|
||
|
|
||
|
MODULE_DEVICE_TABLE(of, cr0014114_dt_ids);
|
||
|
|
||
|
static struct spi_driver cr0014114_driver = {
|
||
|
.probe = cr0014114_probe,
|
||
|
.remove = cr0014114_remove,
|
||
|
.driver = {
|
||
|
.name = KBUILD_MODNAME,
|
||
|
.of_match_table = cr0014114_dt_ids,
|
||
|
},
|
||
|
};
|
||
|
|
||
|
module_spi_driver(cr0014114_driver);
|
||
|
|
||
|
MODULE_AUTHOR("Oleh Kravchenko <oleg@kaa.org.ua>");
|
||
|
MODULE_DESCRIPTION("cr0014114 LED driver");
|
||
|
MODULE_LICENSE("GPL v2");
|
||
|
MODULE_ALIAS("spi:cr0014114");
|