From: Daniel Mack Date: Fri, 19 Dec 2025 15:45:21 +0000 (+0100) Subject: leds: is31f132xx: Add support for is31fl3293 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a18983b95a61b093847b3ec37a5ac9c29ff6257d;p=thirdparty%2Flinux.git leds: is31f132xx: Add support for is31fl3293 This chip supports 3 LED channels with 4096 possible PWM values. Extend the driver to support this variant: * Make brightness steps configurable per device type * Handle dual-register brightness updates * Allow to specify values to write into the PWM update register * Add custom init and shutdown function for 3293 variant * Init registers after parsing DT properties Signed-off-by: Daniel Mack Link: https://patch.msgid.link/20251219154521.643312-4-daniel@zonque.org Signed-off-by: Lee Jones --- diff --git a/drivers/leds/leds-is31fl32xx.c b/drivers/leds/leds-is31fl32xx.c index bd5323f2316e..fe07acbb103a 100644 --- a/drivers/leds/leds-is31fl32xx.c +++ b/drivers/leds/leds-is31fl32xx.c @@ -34,10 +34,26 @@ #define IS31FL32XX_PWM_FREQUENCY_22KHZ 0x01 +/* Registers for IS31FL3293 */ +#define IS31FL3293_SHUTDOWN_REG 0x01 +#define IS31FL3293_SHUTDOWN_SSD_DISABLE BIT(0) +#define IS31FL3293_SHUTDOWN_EN1 BIT(4) +#define IS31FL3293_SHUTDOWN_EN2 BIT(5) +#define IS31FL3293_SHUTDOWN_EN3 BIT(6) +#define IS31FL3293_GCC_REG 0x03 +#define IS31FL3293_GCC_LEVEL_MAX 0x3f +#define IS31FL3293_CL_REG 0x10 +#define IS31FL3293_COLOR_UPDATE_REG 0x27 +#define IS31FL3293_COLOR_UPDATE_MAGIC 0xc5 +#define IS31FL3293_RESET_REG 0x3c +#define IS31FL3293_RESET_MAGIC 0xc5 +#define IS31FL3293_MAX_MICROAMP 20000 + struct is31fl32xx_priv; struct is31fl32xx_led_data { struct led_classdev cdev; u8 channel; /* 1-based, max priv->cdef->channels */ + u32 max_microamp; struct is31fl32xx_priv *priv; }; @@ -53,6 +69,7 @@ struct is31fl32xx_priv { * @channels : Number of LED channels * @shutdown_reg : address of Shutdown register (optional) * @pwm_update_reg : address of PWM Update register + * @pwm_update_value : value to write to PWM Update register * @global_control_reg : address of Global Control register (optional) * @reset_reg : address of Reset register (optional) * @output_frequency_setting_reg: address of output frequency register (optional) @@ -60,6 +77,7 @@ struct is31fl32xx_priv { * @pwm_registers_reversed: : true if PWM registers count down instead of up * @led_control_register_base : address of first LED control register (optional) * @enable_bits_per_led_control_register: number of LEDs enable bits in each + * @brightness_steps : number of brightness steps supported by the chip * @reset_func : pointer to reset function * @sw_shutdown_func : pointer to software shutdown function * @@ -77,6 +95,7 @@ struct is31fl32xx_chipdef { u8 channels; u8 shutdown_reg; u8 pwm_update_reg; + u8 pwm_update_value; u8 global_control_reg; u8 reset_reg; u8 output_frequency_setting_reg; @@ -84,6 +103,7 @@ struct is31fl32xx_chipdef { bool pwm_registers_reversed; u8 led_control_register_base; u8 enable_bits_per_led_control_register; + u16 brightness_steps; int (*reset_func)(struct is31fl32xx_priv *priv); int (*sw_shutdown_func)(struct is31fl32xx_priv *priv, bool enable); }; @@ -152,6 +172,62 @@ static int is31fl3216_software_shutdown(struct is31fl32xx_priv *priv, return is31fl32xx_write(priv, IS31FL3216_CONFIG_REG, value); } +/* + * Custom Reset function for IS31FL3293. We need to set the global current limit + * and write to the color update register once. + */ +static int is31fl3293_reset(struct is31fl32xx_priv *priv) +{ + int i, ret; + + ret = is31fl32xx_write(priv, IS31FL3293_RESET_REG, + IS31FL3293_RESET_MAGIC); + if (ret) + return ret; + + /* Set the global current limit to maximum */ + ret = is31fl32xx_write(priv, IS31FL3293_GCC_REG, + IS31FL3293_GCC_LEVEL_MAX); + if (ret) + return ret; + + for (i = 0; i < priv->num_leds; i++) { + struct is31fl32xx_led_data *led_data = &priv->leds[i]; + int current_level_reg = IS31FL3293_CL_REG + led_data->channel - 1; + int microamp = max(led_data->max_microamp, IS31FL3293_MAX_MICROAMP); + int current_level = (microamp * 0xff) / IS31FL3293_MAX_MICROAMP; + + ret = is31fl32xx_write(priv, current_level_reg, current_level); + if (ret) + return ret; + } + + ret = is31fl32xx_write(priv, IS31FL3293_COLOR_UPDATE_REG, + IS31FL3293_COLOR_UPDATE_MAGIC); + if (ret) + return ret; + + return 0; +} + +/* + * Custom Software-Shutdown function for IS31FL3293 because the SHUTDOWN + * register of this device also has bits to enable the channels. + */ +static int is31fl3293_software_shutdown(struct is31fl32xx_priv *priv, + bool enable) +{ + u8 value = 0; + + if (!enable) + value = IS31FL3293_SHUTDOWN_SSD_DISABLE | + IS31FL3293_SHUTDOWN_EN1 | + IS31FL3293_SHUTDOWN_EN2 | + IS31FL3293_SHUTDOWN_EN3; + + return is31fl32xx_write(priv, IS31FL3293_SHUTDOWN_REG, value); +} + /* * NOTE: A mutex is not needed in this function because: * - All referenced data is read-only after probe() @@ -190,13 +266,36 @@ static int is31fl32xx_brightness_set(struct led_classdev *led_cdev, else pwm_register_offset = led_data->channel - 1; - ret = is31fl32xx_write(led_data->priv, - cdef->pwm_register_base + pwm_register_offset, - brightness); - if (ret) - return ret; + switch (cdef->brightness_steps) { + case 256: + ret = is31fl32xx_write(led_data->priv, + cdef->pwm_register_base + pwm_register_offset, + brightness); + if (ret) + return ret; + + break; + case 4096: + /* IS31FL329x devices use two registers to store 12 bits of brightness */ + pwm_register_offset *= 2; - return is31fl32xx_write(led_data->priv, cdef->pwm_update_reg, 0); + ret = is31fl32xx_write(led_data->priv, + cdef->pwm_register_base + pwm_register_offset, + brightness & 0xff); + if (ret) + return ret; + + ret = is31fl32xx_write(led_data->priv, + cdef->pwm_register_base + pwm_register_offset + 1, + (brightness >> 8) & 0xf); + if (ret) + return ret; + + break; + } + + return is31fl32xx_write(led_data->priv, cdef->pwm_update_reg, + cdef->pwm_update_value); } static int is31fl32xx_reset_regs(struct is31fl32xx_priv *priv) @@ -295,6 +394,8 @@ static int is31fl32xx_parse_child_dt(const struct device *dev, } led_data->channel = reg; + of_property_read_u32(child, "led-max-microamp", &led_data->max_microamp); + cdev->brightness_set_blocking = is31fl32xx_brightness_set; return 0; @@ -339,6 +440,7 @@ static int is31fl32xx_parse_dt(struct device *dev, const struct is31fl32xx_led_data *other_led_data; led_data->priv = priv; + led_data->cdev.max_brightness = priv->cdef->brightness_steps - 1; ret = is31fl32xx_parse_child_dt(dev, child, led_data); if (ret) @@ -391,6 +493,7 @@ static const struct is31fl32xx_chipdef is31fl3236a_cdef = { .pwm_register_base = 0x01, .led_control_register_base = 0x26, .enable_bits_per_led_control_register = 1, + .brightness_steps = 256, }; static const struct is31fl32xx_chipdef is31fl3235_cdef = { @@ -403,6 +506,7 @@ static const struct is31fl32xx_chipdef is31fl3235_cdef = { .pwm_register_base = 0x05, .led_control_register_base = 0x2a, .enable_bits_per_led_control_register = 1, + .brightness_steps = 256, }; static const struct is31fl32xx_chipdef is31fl3218_cdef = { @@ -415,6 +519,7 @@ static const struct is31fl32xx_chipdef is31fl3218_cdef = { .pwm_register_base = 0x01, .led_control_register_base = 0x13, .enable_bits_per_led_control_register = 6, + .brightness_steps = 256, }; static const struct is31fl32xx_chipdef is31fl3216_cdef = { @@ -430,9 +535,25 @@ static const struct is31fl32xx_chipdef is31fl3216_cdef = { .enable_bits_per_led_control_register = 8, .reset_func = is31fl3216_reset, .sw_shutdown_func = is31fl3216_software_shutdown, + .brightness_steps = 256, +}; + +static const struct is31fl32xx_chipdef is31fl3293_cdef = { + .channels = 3, + .shutdown_reg = IS31FL32XX_REG_NONE, + .pwm_update_reg = 0x28, + .pwm_update_value = 0xc5, + .global_control_reg = IS31FL32XX_REG_NONE, + .reset_reg = IS31FL32XX_REG_NONE, + .pwm_register_base = 0x19, + .led_control_register_base = IS31FL32XX_REG_NONE, + .brightness_steps = 4096, + .reset_func = is31fl3293_reset, + .sw_shutdown_func = is31fl3293_software_shutdown, }; static const struct of_device_id of_is31fl32xx_match[] = { + { .compatible = "issi,is31fl3293", .data = &is31fl3293_cdef, }, { .compatible = "issi,is31fl3236", .data = &is31fl3236_cdef, }, { .compatible = "issi,is31fl3236a", .data = &is31fl3236a_cdef, }, { .compatible = "issi,is31fl3235", .data = &is31fl3235_cdef, }, @@ -468,11 +589,11 @@ static int is31fl32xx_probe(struct i2c_client *client) priv->cdef = cdef; i2c_set_clientdata(client, priv); - ret = is31fl32xx_init_regs(priv); + ret = is31fl32xx_parse_dt(dev, priv); if (ret) return ret; - ret = is31fl32xx_parse_dt(dev, priv); + ret = is31fl32xx_init_regs(priv); if (ret) return ret; @@ -495,6 +616,7 @@ static void is31fl32xx_remove(struct i2c_client *client) * even though it is not used for DeviceTree based instantiation. */ static const struct i2c_device_id is31fl32xx_id[] = { + { "is31fl3293" }, { "is31fl3236" }, { "is31fl3236a" }, { "is31fl3235" },