Thanks for comments.
On 12.03.18 17:45, Peter Meerwald-Stadler wrote:
> trivial comments below
>
>> This patch adds a LED class driver for the RGB LEDs found on
>> the Crane Merchandising System CR0014114 LEDs board.
>>
>> Signed-off-by: Oleh Kravchenko <oleg@xxxxxxxxxx>
>> ---
>> .../devicetree/bindings/leds/leds-cr0014114.txt | 46 ++++
>> .../devicetree/bindings/vendor-prefixes.txt | 1 +
>> drivers/leds/Kconfig | 13 +
>> drivers/leds/Makefile | 1 +
>> drivers/leds/leds-cr0014114.c | 282 +++++++++++++++++++++
>> 5 files changed, 343 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/leds/leds-cr0014114.txt
>> create mode 100644 drivers/leds/leds-cr0014114.c
>>
>> diff --git a/Documentation/devicetree/bindings/leds/leds-cr0014114.txt b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt
>> new file mode 100644
>> index 000000000000..56721598ee81
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt
>> @@ -0,0 +1,46 @@
>> +Crane Merchandising System - cr0014114 LED driver
>> +-------------------------------------------------
>> +
>> +This LED Board widely used in vending machines produced
> _is_ widely used
>
>> +by Crane Merchandising Systems.
>> +
>> +Required properties:
>> +- compatible: "cms,cr0014114"
>> +- reg: chip select address for the device
>> +- spi-cpha: shifted clock phase mode is required
>> +
>> +LED sub-node properties:
>> +- label : (optional)
>> + see Documentation/devicetree/bindings/leds/common.txt
>> +- linux,default-trigger : (optional)
>> + see Documentation/devicetree/bindings/leds/common.txt
>> +
>> +Example
>> +-------
>> +
>> +cr0014114@0 {
>> + compatible = "crane,cr0014114";
>> + reg = <0>;
>> + spi-max-frequency = <50000>;
>> + spi-cpha;
>> +
>> + led0 {
>> + label = "cr0:red:";
>> + };
>> + led1 {
>> + label = "cr0:green:";
>> + };
>> + led2 {
>> + label = "cr0:blue:";
>> + };
>> + led3 {
>> + label = "cr1:red:";
>> + };
>> + led4 {
>> + label = "cr1:green:";
>> + };
>> + led5 {
>> + label = "cr1:blue:";
>> + };
>> + ...
>> +};
>> diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
>> index ae850d6c0ad3..f17949c365f5 100644
>> --- a/Documentation/devicetree/bindings/vendor-prefixes.txt
>> +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
>> @@ -75,6 +75,7 @@ cnxt Conexant Systems, Inc.
>> compulab CompuLab Ltd.
>> cortina Cortina Systems, Inc.
>> cosmic Cosmic Circuits
>> +crane Crane Connectivity Solutions
>> creative Creative Technology Ltd
>> crystalfontz Crystalfontz America, Inc.
>> cubietech Cubietech, Ltd.
>> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
>> index 2c896c0e69e1..bb6a70ac5004 100644
>> --- a/drivers/leds/Kconfig
>> +++ b/drivers/leds/Kconfig
>> @@ -104,6 +104,19 @@ config LEDS_CPCAP
>> This option enables support for LEDs offered by Motorola's
>> CPCAP PMIC.
>>
>> +config LEDS_CR0014114
>> + tristate "LED Support for Crane CR0014114"
>> + depends on LEDS_CLASS
>> + depends on SPI
>> + depends on OF
>> + help
>> + This option enables support for CR0014114 LED Board which
>> + widely used in vending machines produced by
> is widely
>
>> + Crane Merchandising Systems.
>> +
>> + To compile this driver as a module, choose M here: the module
>> + will be called leds-cr0014114.
>> +
>> config LEDS_LM3530
>> tristate "LCD Backlight driver for LM3530"
>> depends on LEDS_CLASS
>> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
>> index 91eca81cae82..0176e7335994 100644
>> --- a/drivers/leds/Makefile
>> +++ b/drivers/leds/Makefile
>> @@ -78,6 +78,7 @@ obj-$(CONFIG_LEDS_MT6323) += leds-mt6323.o
>> obj-$(CONFIG_LEDS_LM3692X) += leds-lm3692x.o
>>
>> # LED SPI Drivers
>> +obj-$(CONFIG_LEDS_CR0014114) += leds-cr0014114.o
>> obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o
>>
>> # LED Userspace Drivers
>> diff --git a/drivers/leds/leds-cr0014114.c b/drivers/leds/leds-cr0014114.c
>> new file mode 100644
>> index 000000000000..e3aecdbea73c
>> --- /dev/null
>> +++ b/drivers/leds/leds-cr0014114.c
>> @@ -0,0 +1,282 @@
>> +#include <linux/delay.h>
>> +#include <linux/leds.h>
>> +#include <linux/module.h>
>> +#include <linux/of_device.h>
>> +#include <linux/property.h>
>> +#include <linux/spi/spi.h>
>> +#include <linux/spinlock.h>
>> +#include <linux/timer.h>
>> +#include <linux/workqueue.h>
>> +
>> +/* 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 {
>> + const char *name;
>> + struct cr0014114 *priv;
>> + struct led_classdev ldev;
>> + u8 brightness;
>> +};
>> +
>> +struct cr0014114 {
>> + bool do_recount;
>> + size_t count;
>> + struct device *dev;
>> + struct mutex lock;
>> + struct spi_device *spi;
>> + struct timer_list timer;
>> + struct work_struct work;
>> + 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 to SPI commands */
> matches the
>
>> + 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, "recount of LEDs is started\n");
>> +
>> + do {
>> + cmd = CR_INIT_REENUMERATE;
>> + ret = spi_write(priv->spi, &cmd, sizeof(cmd));
>> + if (ret)
>> + break;
>> +
>> + 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)
>> + break;
>> + }
>> + } while (0);
>> +
>> + dev_dbg(priv->dev, "recount of LEDs is complete, error: %d\n", ret);
>> +
>> + return ret;
>> +}
>> +
>> +static int cr0014114_sync(struct cr0014114 *priv)
>> +{
>> + int ret;
>> + size_t i;
>> + u8 data[priv->count + 2];
>> + 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);
>> + }
>> +
>> + do {
>> + if (unlikely(priv->do_recount)) {
>> + ret = cr0014114_recount(priv);
>> + if (ret)
>> + break;
>> +
>> + priv->do_recount = false;
>> + }
>> +
>> + data[0] = CR_SET_BRIGHTNESS;
>> + for (i = 0; i < priv->count; i++)
>> + data[i + 1] = priv->leds[i].brightness;
>> + cr0014114_calc_crc(data, sizeof(data));
>> +
>> + ret = spi_write(priv->spi, data, sizeof(data));
>> + if (ret)
>> + break;
>> + } while (0);
>> +
>> + 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);
>> +
>> + mutex_lock(&priv->lock);
>> + priv->do_recount = true;
>> + ret = cr0014114_sync(priv);
>> + mutex_unlock(&priv->lock);
>> +
>> + if (ret)
>> + dev_warn(priv->dev, "recount LEDs failed %d\n", ret);
>> +}
>> +
>> +int cr0014114_set_sync(struct led_classdev *ldev,
> static?
>
>> + enum led_brightness brightness)
>> +{
>> + int ret;
>> + struct cr0014114_led *led = container_of(ldev,
>> + struct cr0014114_led,
>> + ldev);
>> +
>> + mutex_lock(&led->priv->lock);
>> + led->brightness = (u8)brightness;
>> + ret = cr0014114_sync(led->priv);
>> + mutex_unlock(&led->priv->lock);
>> +
>> + return ret;
>> +}
>> +
>> +void cr0014114_recount_timer(struct timer_list *t)
> static?
>
>> +{
>> + struct cr0014114 *priv = from_timer(priv, t, timer);
>> +
>> + schedule_work(&priv->work);
>> + mod_timer(&priv->timer, jiffies + CR_RECOUNT_DELAY);
>> +}
>> +
>> +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;
>> +
>> + device_for_each_child_node(priv->dev, child) {
>> + np = to_of_node(child);
>> + led = &priv->leds[i];
>> +
>> + ret = fwnode_property_read_string(child, "label",
>> + &led->name);
>> + if (ret && IS_ENABLED(CONFIG_OF) && np)
>> + led->name = np->name;
>> +
>> + if (!led->name) {
>> + fwnode_handle_put(child);
>> + return -EINVAL;
>> + }
>> +
>> + fwnode_property_read_string(child, "linux,default-trigger",
>> + &led->ldev.default_trigger);
>> +
>> + led->priv = priv;
>> + led->ldev.name = led->name;
>> + led->ldev.brightness = LED_OFF;
>> + 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) {
>> + 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;
>> +
>> + mutex_init(&priv->lock);
>> + INIT_WORK(&priv->work, cr0014114_recount_work);
>> + priv->do_recount = true;
>> + priv->count = count;
>> + priv->dev = &spi->dev;
>> + priv->spi = spi;
>> +
>> + ret = cr0014114_probe_dt(priv);
>> + if (ret)
>> + return ret;
>> +
>> + ret = cr0014114_sync(priv);
>> + if (ret)
>> + return ret;
>> +
>> + /* setup recount timer to workaround buggy firmware */
>> + timer_setup(&priv->timer, cr0014114_recount_timer, 0);
>> + mod_timer(&priv->timer, jiffies + 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_work_sync(&priv->work);
>> + del_timer_sync(&priv->timer);
>> +
>> + 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@xxxxxxxxxx>");
>> +MODULE_DESCRIPTION("cr0014114 LED driver");
>> +MODULE_LICENSE("GPL");
>> +MODULE_ALIAS("spi:cr0014114");
>>
--
Best regards,
Oleh Kravchenko
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