Hello Jacek,
Few question from my side just for better understanding :)
> 5 вер. 2019 р. о 12:23 дп Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx> написав(ла):
>
> Hi Oleh,
>
> Thank you for the updated set.
>
> Now it looks really good. Just few minor issues left.
>
> And side note - please address the patches also to maintainers,
> not only to the list.
>
> On 8/31/19 12:46 AM, Oleh Kravchenko wrote:
>> This patch adds a LED class driver for the RGB LEDs found on
>> the Crane Merchandising System EL15203000 LEDs board
>> (aka RED LEDs board).
>>
>> Signed-off-by: Oleh Kravchenko <oleg@xxxxxxxxxx>
>> ---
>> .../testing/sysfs-class-led-driver-el15203000 | 22 ++
>> drivers/leds/Kconfig | 13 +
>> drivers/leds/Makefile | 1 +
>> drivers/leds/leds-el15203000.c | 362 ++++++++++++++++++
>> 4 files changed, 398 insertions(+)
>> create mode 100644 Documentation/ABI/testing/sysfs-class-led-driver-el15203000
>> create mode 100644 drivers/leds/leds-el15203000.c
>>
>> diff --git a/Documentation/ABI/testing/sysfs-class-led-driver-el15203000 b/Documentation/ABI/testing/sysfs-class-led-driver-el15203000
>> new file mode 100644
>> index 000000000000..767763409125
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/sysfs-class-led-driver-el15203000
>> @@ -0,0 +1,22 @@
>> +What: /sys/class/leds/<led>/hw_pattern
>> +Date: August 2019
>> +KernelVersion: 5.3
>
> Now it will be September and 5.5. It is late even for 5.4.
Here should month of patch creation or when it will be reviewed? :)
Because I sent in 31 August.
>
>> +Description:
>> + Specify a hardware pattern for the EL15203000 LED.
>> + The LEDs board supports only predefined patterns by firmware
>> + for specific LEDs.
>> +
>> + Breathing mode for Screen frame light tube:
>> + "0 4000 1 4000"
>> +
>> + Cascade mode for Pipe LED:
>> + "1 800 2 800 4 800 8 800 16 800"
>> +
>> + Inverted cascade mode for Pipe LED:
>> + "30 800 29 800 27 800 23 800 15 800"
>> +
>> + Bounce mode for Pipe LED:
>> + "1 800 2 800 4 800 8 800 16 800 16 800 8 800 4 800 2 800 1 800"
>> +
>> + Inverted bounce mode for Pipe LED:
>> + "30 800 29 800 27 800 23 800 15 800 15 800 23 800 27 800 29 800 30 800"
>> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
>> index 1988de1d64c0..6e7703fd03d0 100644
>> --- a/drivers/leds/Kconfig
>> +++ b/drivers/leds/Kconfig
>> @@ -132,6 +132,19 @@ config LEDS_CR0014114
>> To compile this driver as a module, choose M here: the module
>> will be called leds-cr0014114.
>>
>> +config LEDS_EL15203000
>> + tristate "LED Support for Crane EL15203000"
>> + depends on LEDS_CLASS
>> + depends on SPI
>> + depends on OF
>> + help
>> + This option enables support for EL15203000 LED Board
>> + (aka RED LED board) which is widely used in coffee vending
>> + machines produced by Crane Merchandising Systems.
>> +
>> + To compile this driver as a module, choose M here: the module
>> + will be called leds-el15203000.
>> +
>> config LEDS_LM3530
>> tristate "LCD Backlight driver for LM3530"
>> depends on LEDS_CLASS
>> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
>> index 41fb073a39c1..2da39e896ce8 100644
>> --- a/drivers/leds/Makefile
>> +++ b/drivers/leds/Makefile
>> @@ -89,6 +89,7 @@ obj-$(CONFIG_LEDS_LM36274) += leds-lm36274.o
>> # LED SPI Drivers
>> obj-$(CONFIG_LEDS_CR0014114) += leds-cr0014114.o
>> obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o
>> +obj-$(CONFIG_LEDS_EL15203000) += leds-el15203000.o
>>
>> # LED Userspace Drivers
>> obj-$(CONFIG_LEDS_USER) += uleds.o
>> diff --git a/drivers/leds/leds-el15203000.c b/drivers/leds/leds-el15203000.c
>> new file mode 100644
>> index 000000000000..9de81dee3618
>> --- /dev/null
>> +++ b/drivers/leds/leds-el15203000.c
>> @@ -0,0 +1,362 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +// Copyright (c) 2019 Crane Merchandising Systems. All rights reserved.
>> +// Copyright (C) 2019 Oleh Kravchenko <oleg@xxxxxxxxxx>
>> +
>> +#include <linux/delay.h>
>> +#include <linux/leds.h>
>> +#include <linux/module.h>
>> +#include <linux/of_device.h>
>> +#include <linux/spi/spi.h>
>> +
>> +/*
>> + * EL15203000 SPI protocol description:
>> + * +-----+---------+
>> + * | LED | COMMAND |
>> + * +-----+---------+
>> + * | 1 | 1 |
>> + * +-----+---------+
>> + * (*) LEDs MCU board expects 20 msec delay per byte.
>> + *
>> + * LEDs:
>> + * +----------+--------------+-------------------------------------------+
>> + * | ID | NAME | DESCRIPTION |
>> + * +----------+--------------+-------------------------------------------+
>> + * | 'P' 0x50 | Pipe | Consists from 5 LEDs, controlled by board |
>> + * +----------+--------------+-------------------------------------------+
>> + * | 'S' 0x53 | Screen frame | Light tube around the screen |
>> + * +----------+--------------+-------------------------------------------+
>> + * | 'V' 0x56 | Vending area | Highlights a cup of coffee |
>> + * +----------+--------------+-------------------------------------------+
>> + *
>> + * COMMAND:
>> + * +----------+-----------------+--------------+--------------+
>> + * | VALUES | PIPE | SCREEN FRAME | VENDING AREA |
>> + * +----------+-----------------+--------------+--------------+
>> + * | '0' 0x30 | Off |
>> + * +----------+-----------------------------------------------+
>> + * | '1' 0x31 | On |
>> + * +----------+-----------------+--------------+--------------+
>> + * | '2' 0x32 | Cascade | Breathing |
>> + * +----------+-----------------+--------------+
>> + * | '3' 0x33 | Inverse cascade |
>> + * +----------+-----------------+
>> + * | '4' 0x34 | Bounce |
>> + * +----------+-----------------+
>> + * | '5' 0x35 | Inverse bounce |
>> + * +----------+-----------------+
>> + */
>> +
>> +/* EL15203000 default settings */
>> +#define EL_FW_DELAY_USEC 20000ul
>> +#define EL_PATTERN_DELAY_MSEC 800u
>> +#define EL_PATTERN_LEN 10u
>> +#define EL_PATTERN_HALF_LEN (EL_PATTERN_LEN / 2)
>> +
>> +enum el15203000_command {
>> + /* for all LEDs */
>> + EL_OFF = '0',
>> + EL_ON = '1',
>> +
>> + /* for Screen LED */
>> + EL_SCREEN_BREATHING = '2',
>> +
>> + /* for Pipe LED */
>> + EL_PIPE_CASCADE = '2',
>> + EL_PIPE_INV_CASCADE = '3',
>> + EL_PIPE_BOUNCE = '4',
>> + EL_PIPE_INV_BOUNCE = '5',
>> +};
>> +
>> +struct el15203000_led {
>> + struct el15203000 *priv;
>> + struct led_classdev ldev;
>> + u8 reg;
>> +};
>> +
>> +struct el15203000 {
>> + struct device *dev;
>> + struct mutex lock;
>> + struct spi_device *spi;
>> + unsigned long delay;
>> + size_t count;
>> + struct el15203000_led leds[];
>> +};
>> +
>> +static int el15203000_cmd(struct el15203000_led *led, u8 brightness)
>> +{
>> + int ret;
>> + u8 cmd[2];
>> + size_t i;
>> +
>> + mutex_lock(&led->priv->lock);
>> +
>> + dev_dbg(led->priv->dev, "Set brightness of 0x%02x(%c) to 0x%02x(%c)",
>> + led->reg, led->reg, brightness, brightness);
>> +
>> + /* to avoid SPI mistiming with firmware we should wait some time */
>> + if (time_after(led->priv->delay, jiffies)) {
>> + dev_dbg(led->priv->dev, "Wait %luus to sync",
>> + EL_FW_DELAY_USEC);
>> +
>> + usleep_range(EL_FW_DELAY_USEC,
>> + EL_FW_DELAY_USEC + 1);
>> + }
>> +
>> + cmd[0] = led->reg;
>> + cmd[1] = brightness;
>> +
>> + for (i = 0; i < ARRAY_SIZE(cmd); i++) {
>> + if (i)
>> + usleep_range(EL_FW_DELAY_USEC,
>> + EL_FW_DELAY_USEC + 1);
>> +
>> + ret = spi_write(led->priv->spi, &cmd[i], sizeof(cmd[i]));
>> + if (ret) {
>> + dev_err(led->priv->dev,
>> + "spi_write() error %d", ret);
>> + break;
>> + }
>> + }
>> +
>> + led->priv->delay = jiffies + usecs_to_jiffies(EL_FW_DELAY_USEC);
>> +
>> + mutex_unlock(&led->priv->lock);
>> +
>> + return ret;
>> +}
>> +
>> +static int el15203000_set_blocking(struct led_classdev *ldev,
>> + enum led_brightness brightness)
>> +{
>> + struct el15203000_led *led = container_of(ldev,
>> + struct el15203000_led,
>> + ldev);
>> +
>> + return el15203000_cmd(led, brightness == LED_OFF ? EL_OFF : EL_ON);
>> +}
>> +
>> +static int el15203000_pattern_set_S(struct led_classdev *ldev,
>> + struct led_pattern *pattern,
>> + u32 len, int repeat)
>> +{
>> + struct el15203000_led *led = container_of(ldev,
>> + struct el15203000_led,
>> + ldev);
>> +
>> + if (repeat > 0 || len != 2 ||
>> + pattern[0].delta_t != 4000 || pattern[0].brightness != 0 ||
>> + pattern[1].delta_t != 4000 || pattern[1].brightness != 1)
>> + return -EINVAL;
>> +
>> + dev_dbg(led->priv->dev, "Breathing mode for 0x%02x(%c)",
>> + led->reg, led->reg);
>> +
>> + return el15203000_cmd(led, EL_SCREEN_BREATHING);
>> +}
>> +
>> +static bool is_cascade(const struct led_pattern *pattern, u32 len,
>> + bool inv, bool right)
>> +{
>> + int val, t;
>> + u32 i;
>> +
>> + if (len != EL_PATTERN_HALF_LEN)
>> + return false;
>> +
>> + val = right ? BIT(4) : BIT(0);
>> +
>> + for (i = 0; i < len; i++) {
>> + t = inv ? ~val & GENMASK(4, 0) : val;
>> +
>> + if (pattern[i].delta_t != EL_PATTERN_DELAY_MSEC ||
>> + pattern[i].brightness != t)
>> + return false;
>> +
>> + val = right ? val >> 1 : val << 1;
>> + }
>
> Nice!
>
>> +
>> + return true;
>> +}
>> +
>> +static bool is_bounce(const struct led_pattern *pattern, u32 len, bool inv)
>> +{
>> + if (len != EL_PATTERN_LEN)
>> + return false;
>> +
>> + return is_cascade(pattern, EL_PATTERN_HALF_LEN, inv, false) &&
>> + is_cascade(pattern + EL_PATTERN_HALF_LEN,
>> + EL_PATTERN_HALF_LEN, inv, true);
>> +}
>> +
>> +static int el15203000_pattern_set_P(struct led_classdev *ldev,
>> + struct led_pattern *pattern,
>> + u32 len, int repeat)
>> +{
>> + struct el15203000_led *led = container_of(ldev,
>> + struct el15203000_led,
>> + ldev);
>> +
>> + if (repeat > 0)
>
> This is wrong. Repeat has to be -1 or > 0. If all patterns supported
> by your device are infinite, then you should expect here -1.
Ok, then we have bug in led pattern trigger.
echo -1 > /…/repeat doesn’t work as expected and return error.
So if I tried to change repeat from sysfs, it will never be -1 again.
>
> Either way this needs to be covered in the ABI documentation too.
>
>> + return -EINVAL;
>> +
>> + if (is_cascade(pattern, len, false, false)) {
>> + dev_dbg(led->priv->dev, "Cascade mode for 0x%02x(%c)",
>> + led->reg, led->reg);
>> +
>> + return el15203000_cmd(led, EL_PIPE_CASCADE);
>> + } else if (is_cascade(pattern, len, true, false)) {
>> + dev_dbg(led->priv->dev, "Inverse cascade mode for 0x%02x(%c)",
>> + led->reg, led->reg);
>> +
>> + return el15203000_cmd(led, EL_PIPE_INV_CASCADE);
>> + } else if (is_bounce(pattern, len, false)) {
>> + dev_dbg(led->priv->dev, "Bounce mode for 0x%02x(%c)",
>> + led->reg, led->reg);
>> +
>> + return el15203000_cmd(led, EL_PIPE_BOUNCE);
>> + } else if (is_bounce(pattern, len, true)) {
>> + dev_dbg(led->priv->dev, "Inverse bounce mode for 0x%02x(%c)",
>> + led->reg, led->reg);
>> +
>> + return el15203000_cmd(led, EL_PIPE_INV_BOUNCE);
>> + }
>> +
>> + return -EINVAL;
>> +}
>> +
>> +static int el15203000_pattern_clear(struct led_classdev *ldev)
>> +{
>> + struct el15203000_led *led = container_of(ldev,
>> + struct el15203000_led,
>> + ldev);
>> +
>> + return el15203000_cmd(led, EL_OFF);
>> +}
>> +
>> +static int el15203000_probe_dt(struct el15203000 *priv)
>> +{
>> + size_t i = 0;
>> + struct el15203000_led *led;
>> + struct fwnode_handle *child;
>> + int ret;
>> + u32 reg;
>> + struct led_init_data init_data = {};
>> +
>> + device_for_each_child_node(priv->dev, child) {
>
> Please move above init_data initialization here.
No problem.
>
>
>> + led = &priv->leds[i];
>
> You can increment 'i' here, it is not used below and you will save one
> LOC:
>
> led = &priv->leds[i++];
Agree.
>
>> +
>> + init_data.fwnode = child;
>
> Please move it to where it will be needed. i.e. one line above
> devm_led_classdev_register_ext().
Will do.
>
>> +
>> + ret = fwnode_property_read_u32(child, "reg", ®);
>> + if (ret) {
>> + dev_err(priv->dev, "LED without ID number");
>> + fwnode_handle_put(child);
>> +
>> + return ret;
>> + }
>> +
>> + if (reg > U8_MAX) {
>> + dev_err(priv->dev, "LED value %d is invalid", reg);
>> + fwnode_handle_put(child);
>> +
>> + return -EINVAL;
>> + }
>> +
>> + led->reg = reg;
>
> I'd just pass &led->reg directly to fwnode_property_read_u32().
> Then you'll be able to drop local reg variable.
For this device/driver reg value is just one byte
You are ok to waste 3 bytes for every EL15203000 LED?
>
>> +
>> + fwnode_property_read_string(child, "linux,default-trigger",
>> + &led->ldev.default_trigger);
>> +
>> + led->priv = priv;
>> + led->ldev.max_brightness = LED_ON;
>> + led->ldev.brightness_set_blocking = el15203000_set_blocking;
>> +
>> + if (reg == 'S') {
>> + led->ldev.pattern_set = el15203000_pattern_set_S;
>> + led->ldev.pattern_clear = el15203000_pattern_clear;
>> + } else if (reg == 'P') {
>> + led->ldev.pattern_set = el15203000_pattern_set_P;
>> + led->ldev.pattern_clear = el15203000_pattern_clear;
>> + }
>> +
>> + ret = devm_led_classdev_register_ext(priv->dev, &led->ldev,
>> + &init_data);
>> + if (ret) {
>> + dev_err(priv->dev,
>> + "failed to register LED device %s, err %d",
>> + led->ldev.name, ret);
>> + fwnode_handle_put(child);
>> +
>> + return ret;
>> + }
>> +
>> + i++;
>> + }
>> +
>> + return ret;
>> +}
>> +
>> +static int el15203000_probe(struct spi_device *spi)
>> +{
>> + struct el15203000 *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, struct_size(priv, leds, count),
>> + GFP_KERNEL);
>> + if (!priv)
>> + return -ENOMEM;
>> +
>> + mutex_init(&priv->lock);
>> + priv->count = count;
>> + priv->dev = &spi->dev;
>> + priv->spi = spi;
>> + priv->delay = jiffies -
>> + usecs_to_jiffies(EL_FW_DELAY_USEC);
>> +
>> + ret = el15203000_probe_dt(priv);
>> + if (ret)
>> + return ret;
>> +
>> + spi_set_drvdata(spi, priv);
>> +
>> + return 0;
>> +}
>> +
>> +static int el15203000_remove(struct spi_device *spi)
>> +{
>> + struct el15203000 *priv = spi_get_drvdata(spi);
>> +
>> + mutex_destroy(&priv->lock);
>> +
>> + return 0;
>> +}
>> +
>> +static const struct of_device_id el15203000_dt_ids[] = {
>> + { .compatible = "crane,el15203000", },
>> + {},
>> +};
>> +
>> +MODULE_DEVICE_TABLE(of, el15203000_dt_ids);
>> +
>> +static struct spi_driver el15203000_driver = {
>> + .probe = el15203000_probe,
>> + .remove = el15203000_remove,
>> + .driver = {
>> + .name = KBUILD_MODNAME,
>> + .of_match_table = el15203000_dt_ids,
>> + },
>> +};
>> +
>> +module_spi_driver(el15203000_driver);
>> +
>> +MODULE_AUTHOR("Oleh Kravchenko <oleg@xxxxxxxxxx>");
>> +MODULE_DESCRIPTION("el15203000 LED driver");
>> +MODULE_LICENSE("GPL v2");
>> +MODULE_ALIAS("spi:el15203000");
>>
>
> --
> Best regards,
> Jacek Anaszewski
