Re: [PATCH 2/2] leds: add mp3326 driver

From: Krzysztof Kozlowski
Date: Tue Oct 31 2023 - 04:16:20 EST

On 31/10/2023 08:01, Yuxi (Yuxi) Wang wrote:
>
> This patch adds mp3326 led driver.
>
> Signed-off-by: Yuxi Wang <Yuxi.Wang@xxxxxxxxxxxxxxxxxxx>
> ---
> drivers/leds/Kconfig | 7 +
> drivers/leds/Makefile | 1 +
> drivers/leds/leds-mp3326.c | 632 +++++++++++++++++++++++++++++++++++++
> 3 files changed, 640 insertions(+)
> create mode 100644 drivers/leds/leds-mp3326.c
>
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index b92208eccdea..ac8115bffc2e 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -260,6 +260,13 @@ config LEDS_MIKROTIK_RB532
> This option enables support for the so called "User LED" of
> Mikrotik's Routerboard 532.
>
> +config LEDS_MP3326
> + tristate "LED Support for MPS MP3326"
> + depends on LEDS_CLASS
> + help
> + This option enables support for on-chip LED drivers found on
> + MPS MP3326.
> +
> config LEDS_MT6323
> tristate "LED Support for Mediatek MT6323 PMIC"
> depends on LEDS_CLASS
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index d7348e8bc019..196befb56278 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -63,6 +63,7 @@ obj-$(CONFIG_LEDS_MENF21BMC) += leds-menf21bmc.o
> obj-$(CONFIG_LEDS_MIKROTIK_RB532) += leds-rb532.o
> obj-$(CONFIG_LEDS_MLXCPLD) += leds-mlxcpld.o
> obj-$(CONFIG_LEDS_MLXREG) += leds-mlxreg.o
> +obj-$(CONFIG_LEDS_MP3326) += leds-mp3326.o
> obj-$(CONFIG_LEDS_MT6323) += leds-mt6323.o
> obj-$(CONFIG_LEDS_NET48XX) += leds-net48xx.o
> obj-$(CONFIG_LEDS_NETXBIG) += leds-netxbig.o
> diff --git a/drivers/leds/leds-mp3326.c b/drivers/leds/leds-mp3326.c
> new file mode 100644
> index 000000000000..140c71b334f7
> --- /dev/null
> +++ b/drivers/leds/leds-mp3326.c
> @@ -0,0 +1,632 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * MP3326 Led driver
> + *
> + * Copyright 2023 Monolithic Power Systems, Inc
> + *
> + * Author: Yuxi Wang <Yuxi.Wang@xxxxxxxxxxxxxxxxxxx>
> + */
> +#include <linux/bits.h>
> +#include <linux/module.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/i2c.h>
> +#include <linux/of.h>
> +#include <linux/slab.h>
> +#include <linux/interrupt.h>
> +#include <linux/mutex.h>
> +#include <linux/leds.h>
> +#include <linux/device.h>
> +#include <linux/led-class-multicolor.h>
> +
> +#define MP3326_PWM_DIM_FREQUENCY_CONFIG 0x00
> +#define MP3326_PWM_CTRL 0x01
> +#define MP3326_PWM_DIM_FREQUENCY_CONFIG 0x00
> +#define MP3326_PWM_CTRL_CHANNEL_9_16 0x04
> +#define MP3326_PWM_CTRL_CHANNEL_1_8 0x05
> +#define MP3326_PWM_OPEN_FAULT_CHANNEL_9_16 0x06
> +#define MP3326_PWM_OPEN_FAULT_CHANNEL_1_8 0x07
> +#define MP3326_PWM_SHORT_FAULT_CHANNEL_9_16 0x08
> +#define MP3326_PWM_SHORT_FAULT_CHANNEL_1_8 0x09
> +#define MP3326_PWM_CURRENT_SET_CHANNEL1 0x0A
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL1 0x0B
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL1 0x0C
> +#define MP3326_PWM_CURRENT_SET_CHANNEL2 0x0D
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL2 0x0E
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL2 0x0F
> +#define MP3326_PWM_CURRENT_SET_CHANNEL3 0x10
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL3 0x11
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL3 0x12
> +#define MP3326_PWM_CURRENT_SET_CHANNEL4 0x13
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL4 0x14
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL4 0x15
> +#define MP3326_PWM_CURRENT_SET_CHANNEL5 0x16
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL5 0x17
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL5 0x18
> +#define MP3326_PWM_CURRENT_SET_CHANNEL6 0x19
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL6 0x1A
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL6 0x1B
> +#define MP3326_PWM_CURRENT_SET_CHANNEL7 0x1C
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL7 0x1D
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL7 0x1E
> +#define MP3326_PWM_CURRENT_SET_CHANNEL8 0x1F
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL8 0x20
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL8 0x21
> +#define MP3326_PWM_CURRENT_SET_CHANNEL9 0x22
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL9 0x23
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL9 0x24
> +#define MP3326_PWM_CURRENT_SET_CHANNEL10 0x25
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL10 0x26
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL10 0x27
> +#define MP3326_PWM_CURRENT_SET_CHANNEL11 0x28
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL11 0x29
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL11 0x2A
> +#define MP3326_PWM_CURRENT_SET_CHANNEL12 0x2B
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL12 0x2C
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL12 0x2D
> +#define MP3326_PWM_CURRENT_SET_CHANNEL13 0x2E
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL13 0x2F
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL13 0x30
> +#define MP3326_PWM_CURRENT_SET_CHANNEL14 0x31
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL14 0x32
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL14 0x33
> +#define MP3326_PWM_CURRENT_SET_CHANNEL15 0x34
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL15 0x35
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL15 0x36
> +#define MP3326_PWM_CURRENT_SET_CHANNEL16 0x37
> +#define MP3326_PWM_DUTY_LSB_SET_CHANNEL16 0x38
> +#define MP3326_PWM_DUTY_MSB_SET_CHANNEL16 0x39
> +#define MAX_BRIGHTNESS 63
> +
> +enum led_ctrl {
> + ENABLE = 0,
> + BRIGHTNESS,
> + COLOR_L4,
> + COLOR_H8,
> + OPEN_FAULT,
> + SHORT_FAULT,
> + Max_CTRL,

Dpn't use CamelCase

> +};
> +
> +enum mp3326_channel {
> + Channel1,
> + Channel2,
> + Channel3,
> + Channel4,
> + Channel5,
> + Channel6,
> + Channel7,
> + Channel8,
> + Channel9,
> + Channel10,
> + Channel11,
> + Channel12,
> + Channel13,
> + Channel14,
> + Channel15,
> + Channel16,

Ditto


> + Max_Channel,> +};
> +
> +#define MP3326_Reg_Connect_Inner(prefix, range) prefix##range
> +#define MP3326_Reg_Connect(prefix, range) MP3326_Reg_Connect_Inner(prefix, range)
> +#define MP3326_Reg_Field(reg, minbit, maxbit) REG_FIELD(reg, minbit, maxbit)
> +#define Range1(a, b) MP3326_Reg_Connect_Inner(a, b)
> +#define Range2(a, b) MP3326_Reg_Connect_Inner(a, b)

OK, so this driver was copied from some out-of-tree, poor quality old
code not even using Linux coding style. Please rewrite everything to
match Linux coding style.

> +
> +#define MP3326_Channel_FIELD(bit, num, range) { \
> + MP3326_Reg_Field(MP3326_Reg_Connect(MP3326_PWM_CTRL_CHANNEL_, range), bit, bit), \
> + MP3326_Reg_Field(MP3326_Reg_Connect(MP3326_PWM_CURRENT_SET_CHANNEL, num), 0, 5), \
> + MP3326_Reg_Field(MP3326_Reg_Connect(MP3326_PWM_DUTY_LSB_SET_CHANNEL, num), 0, 3), \
> + MP3326_Reg_Field(MP3326_Reg_Connect(MP3326_PWM_DUTY_MSB_SET_CHANNEL, num), 0, 7), \
> + MP3326_Reg_Field(MP3326_Reg_Connect(MP3326_PWM_OPEN_FAULT_CHANNEL_, range), bit, bit), \
> + MP3326_Reg_Field(MP3326_Reg_Connect(MP3326_PWM_SHORT_FAULT_CHANNEL_, range), bit, bit), \
> + }
> +struct mp3326_led {
> + struct mp3326 *private_data;
> + struct led_classdev cdev;
> + struct mc_subled *subled_info;
> + int num_colors;
> +};

...

> +
> + for_each_available_child_of_node(np, child) {
> + ret = of_property_read_u32(child, "reg", &reg);
> + if (ret || reg > Max_Channel) {
> + dev_err(&chip->client->dev,
> + "reg must less or equal than %d\n", Max_Channel);
> + return -EINVAL;
> + }
> +
> + ret = of_property_read_u32(child, "color", &color);
> + if (ret) {
> + dev_err(&chip->client->dev, "color must have value\n");
> + return ret;
> + }
> +
> + if (color > 3 || !color) {
> + dev_err(&chip->client->dev,
> + "color must be Red, Green and Blue. The color is %d\n", color);

Broken indentation. Everywhere. Be sure that checkpatch --strict does
not print any (any!) warnings.

> + return ret;
> + }
> + info[i].color_index = color;
> + info[i].channel = reg - 1;
> + info[i].brightness = 0;
> + i++;
> + }
> +
> + led->subled_info = info;
> + led->num_colors = 3;
> + cdev = &led->cdev;
> + cdev->max_brightness = MAX_BRIGHTNESS;
> + cdev->brightness_set_blocking = led_brightness_set;
> + cdev->groups = led_sysfs_groups;
> + init_data.fwnode = &np->fwnode;
> +
> + ret = devm_led_classdev_register_ext(&chip->client->dev, &led->cdev, &init_data);
> +
> + if (ret) {
> + dev_err(&chip->client->dev, "Unable register multicolor:%s\n", cdev->name);
> + return ret;
> + }
> + } else {
> + ret = of_property_read_u32(np, "reg", &reg);
> + if (ret || reg > Max_Channel) {
> + dev_err(&chip->client->dev,
> + "reg must less or equal than %d\n", Max_Channel);
> + return -EINVAL;
> + }
> + info = devm_kcalloc(&chip->client->dev, 1, sizeof(*info), GFP_KERNEL);
> + led->num_colors = 1;
> + info[i].color_index = LED_COLOR_ID_WHITE;
> + info[i].channel = reg - 1;
> + info[i].brightness = 0;
> + led->subled_info = info;
> + cdev = &led->cdev;
> + cdev->max_brightness = MAX_BRIGHTNESS;
> + cdev->brightness_set_blocking = led_brightness_set;
> + cdev->groups = led_sysfs_groups;
> + init_data.fwnode = &np->fwnode;
> + ret = devm_led_classdev_register_ext(&chip->client->dev, &led->cdev, &init_data);
> + if (ret) {
> + dev_err(&chip->client->dev, "Unable register led:%s\n", cdev->name);
> + return ret;
> + }
> + }
> + return ret;
> +}
> +
> +static int mp3326_parse_dt(struct mp3326 *chip)
> +{
> + struct device_node *np = dev_of_node(&chip->client->dev);
> + struct device_node *child;
> + int ret;
> + int index;

iteration variables have name 'i'. Not index.

> + int val;
> +
> + for_each_available_child_of_node(np, child) {
> + ret = mp3326_add_led(chip, child, index);
> + if (ret)
> + return ret;
> + index++;
> + }
> + ret = of_property_read_u32(np, "led-protect", &val);
> + if (ret)
> + return ret;
> +
> + ret = regmap_update_bits(chip->regmap, 0x01, BIT(4) | BIT(5), val << 4);
> +
> + ret = regmap_write(chip->regmap, MP3326_PWM_CTRL_CHANNEL_9_16, 0);
> + if (ret)
> + return ret;
> + ret = regmap_write(chip->regmap, MP3326_PWM_CTRL_CHANNEL_1_8, 0);
> + if (ret)
> + return ret;
> + return 0;
> +}
> +
> +static int mp3326_leds_probe(struct i2c_client *client)
> +{
> + struct mp3326 *chip;
> + const struct reg_field *reg_fields;
> + int count, i, j;
> +
> + count = device_get_child_node_count(&client->dev);
> + if (!count) {
> + return dev_err_probe(&client->dev, -EINVAL,
> + "Incorrect number of leds (%d)", count);
> + }
> + chip = devm_kzalloc(&client->dev, struct_size(chip, leds, count), GFP_KERNEL);
> + if (!chip)
> + return -ENOMEM;
> +
> + chip->client = client;
> + chip->num_of_leds = count;
> + i2c_set_clientdata(client, chip);
> + chip->regmap = devm_regmap_init_i2c(client, &MP3326_regmap_config);
> + if (IS_ERR(chip->regmap))
> + return PTR_ERR(chip->regmap);
> +
> + for (i = 0; i < Max_Channel; i++) {
> + reg_fields = channels_reg_fields[i];
> + for (j = 0; j < Max_CTRL; j++) {
> + chip->regmap_fields[i][j] = devm_regmap_field_alloc(&client->dev,
> + chip->regmap, reg_fields[j]);
> + if (IS_ERR(chip->regmap_fields[i][j])) {
> + dev_err(&client->dev,
> + "regmap field alloc fail, channel:%d, item: %d\n", i, j);
> + return PTR_ERR(chip->regmap_fields[i][j]);

Messed indentation. Anyway, memory allocation errors are not usually
printed. Why should they be printed here?


> + }
> + }
> + }
> + if (mp3326_parse_dt(chip))
> + return 1;
> + else
> + return 0;
> +}
> +
> +static const struct i2c_device_id mp3326_id[] = {
> + {"mp3326", 0},
> + {}
> +};
> +MODULE_DEVICE_TABLE(i2c, mp3326_id);
> +
> +static const struct of_device_id mp3326_of_match[] = {
> + { .compatible = "mps,mp3326" },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, mp3326_of_match);
> +
> +static struct i2c_driver mp3326_driver = {
> + .probe_new = mp3326_leds_probe,
> + .driver = {
> + .owner = THIS_MODULE,

Drop. Kernel does not have it since few years.


> + .name = "MP3326_led",

One less indent.

> + .of_match_table = mp3326_of_match,
> + },
> + .id_table = mp3326_id,
> +};
> +
> +module_i2c_driver(mp3326_driver);
> +MODULE_AUTHOR("Yuxi Wang <Yuxi.Wang@xxxxxxxxxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("MPS MP3326 LED driver");
> +MODULE_LICENSE("GPL");

Best regards,
Krzysztof