From 87f33a1b8f7e3d223fc331fe54fd8ec337dc9cb9 Mon Sep 17 00:00:00 2001 From: Flavio Suligoi Date: Thu, 16 Nov 2023 11:53:18 +0100 Subject: [PATCH 1/7] dt-bindings: backlight: mp3309c: Remove two required properties The two properties: - max-brightness - default brightness are not really required, so they can be removed from the "required" section. The "max-brightness" is no longer used in the current version of the driver (it was used only in the first version). The "default-brightness", if omitted in the DT, is managed by the device driver, using a default value. This value depends on the dimming mode used: - for the "analog mode", via I2C commands, this value is fixed by hardware (=31) - while in case of pwm mode the default used is the last value of the brightness-levels array. Also the brightness-levels array is not required: - in "analog mode", via I2C commands, the brightness-level array is fixed by hardware (0..31).; - in pwm dimming mode, the driver uses a default array of 0..255 and the "default-brightness" is the last one, which is "255" NOTE: there are no compatibility problems with the previous version, since the device driver has not yet been included in any kernel. Only this dt-binding yaml file is already included in the current v6.7.0-rc1 kernel version. No developer may have used it. Other changes: - improve the backlight working mode description, in the "description" section - update the example, removing the "max-brightness" and introducing the "brightess-levels" property Signed-off-by: Flavio Suligoi Acked-by: Conor Dooley Reviewed-by: Daniel Thompson Link: https://lore.kernel.org/r/20231116105319.957600-2-f.suligoi@asem.it Signed-off-by: Lee Jones --- .../bindings/leds/backlight/mps,mp3309c.yaml | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml b/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml index 4191e33626f5..527a37368ed7 100644 --- a/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml +++ b/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml @@ -14,8 +14,8 @@ description: | programmable switching frequency to optimize efficiency. It supports two different dimming modes: - - analog mode, via I2C commands (default) - - PWM controlled mode. + - analog mode, via I2C commands, as default mode (32 dimming levels) + - PWM controlled mode (optional) The datasheet is available at: https://www.monolithicpower.com/en/mp3309c.html @@ -50,8 +50,6 @@ properties: required: - compatible - reg - - max-brightness - - default-brightness unevaluatedProperties: false @@ -66,8 +64,8 @@ examples: compatible = "mps,mp3309c"; reg = <0x17>; pwms = <&pwm1 0 3333333 0>; /* 300 Hz --> (1/f) * 1*10^9 */ - max-brightness = <100>; - default-brightness = <80>; + brightness-levels = <0 4 8 16 32 64 128 255>; + default-brightness = <6>; mps,overvoltage-protection-microvolt = <24000000>; }; }; From 2e914516a58cf86bd0e42c7d3e25c81d44ec2ab8 Mon Sep 17 00:00:00 2001 From: Flavio Suligoi Date: Thu, 16 Nov 2023 11:53:19 +0100 Subject: [PATCH 2/7] backlight: mp3309c: Add support for MPS MP3309C The Monolithic Power (MPS) MP3309C is a WLED step-up converter, featuring a programmable switching frequency to optimize efficiency. The brightness can be controlled either by I2C commands (called "analog" mode) or by a PWM input signal (PWM mode). This driver supports both modes. For DT configuration details, please refer to: - Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml The datasheet is available at: - https://www.monolithicpower.com/en/mp3309c.html Signed-off-by: Flavio Suligoi Reviewed-by: Daniel Thompson Link: https://lore.kernel.org/r/20231116105319.957600-3-f.suligoi@asem.it Signed-off-by: Lee Jones --- MAINTAINERS | 7 + drivers/video/backlight/Kconfig | 11 + drivers/video/backlight/Makefile | 1 + drivers/video/backlight/mp3309c.c | 443 ++++++++++++++++++++++++++++++ 4 files changed, 462 insertions(+) create mode 100644 drivers/video/backlight/mp3309c.c diff --git a/MAINTAINERS b/MAINTAINERS index 97f51d5ec1cf..c00952c46202 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -14658,6 +14658,13 @@ S: Maintained F: Documentation/driver-api/tty/moxa-smartio.rst F: drivers/tty/mxser.* +MP3309C BACKLIGHT DRIVER +M: Flavio Suligoi +L: dri-devel@lists.freedesktop.org +S: Maintained +F: Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml +F: drivers/video/backlight/mp3309c.c + MR800 AVERMEDIA USB FM RADIO DRIVER M: Alexey Klimov L: linux-media@vger.kernel.org diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index 51387b1ef012..1144a54a35c0 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -402,6 +402,17 @@ config BACKLIGHT_LP8788 help This supports TI LP8788 backlight driver. +config BACKLIGHT_MP3309C + tristate "Backlight Driver for MPS MP3309C" + depends on I2C && PWM + select REGMAP_I2C + help + This supports MPS MP3309C backlight WLED driver in both PWM and + analog/I2C dimming modes. + + To compile this driver as a module, choose M here: the module will + be called mp3309c. + config BACKLIGHT_PANDORA tristate "Backlight driver for Pandora console" depends on TWL4030_CORE diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile index f72e1c3c59e9..1af583de665b 100644 --- a/drivers/video/backlight/Makefile +++ b/drivers/video/backlight/Makefile @@ -44,6 +44,7 @@ obj-$(CONFIG_BACKLIGHT_LP855X) += lp855x_bl.o obj-$(CONFIG_BACKLIGHT_LP8788) += lp8788_bl.o obj-$(CONFIG_BACKLIGHT_LV5207LP) += lv5207lp.o obj-$(CONFIG_BACKLIGHT_MAX8925) += max8925_bl.o +obj-$(CONFIG_BACKLIGHT_MP3309C) += mp3309c.o obj-$(CONFIG_BACKLIGHT_MT6370) += mt6370-backlight.o obj-$(CONFIG_BACKLIGHT_OMAP1) += omap1_bl.o obj-$(CONFIG_BACKLIGHT_PANDORA) += pandora_bl.o diff --git a/drivers/video/backlight/mp3309c.c b/drivers/video/backlight/mp3309c.c new file mode 100644 index 000000000000..3fe4469ef43f --- /dev/null +++ b/drivers/video/backlight/mp3309c.c @@ -0,0 +1,443 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for MPS MP3309C White LED driver with I2C interface + * + * This driver support both analog (by I2C commands) and PWM dimming control + * modes. + * + * Copyright (C) 2023 ASEM Srl + * Author: Flavio Suligoi + * + * Based on pwm_bl.c + */ + +#include +#include +#include +#include +#include +#include + +#define REG_I2C_0 0x00 +#define REG_I2C_1 0x01 + +#define REG_I2C_0_EN 0x80 +#define REG_I2C_0_D0 0x40 +#define REG_I2C_0_D1 0x20 +#define REG_I2C_0_D2 0x10 +#define REG_I2C_0_D3 0x08 +#define REG_I2C_0_D4 0x04 +#define REG_I2C_0_RSRV1 0x02 +#define REG_I2C_0_RSRV2 0x01 + +#define REG_I2C_1_RSRV1 0x80 +#define REG_I2C_1_DIMS 0x40 +#define REG_I2C_1_SYNC 0x20 +#define REG_I2C_1_OVP0 0x10 +#define REG_I2C_1_OVP1 0x08 +#define REG_I2C_1_VOS 0x04 +#define REG_I2C_1_LEDO 0x02 +#define REG_I2C_1_OTP 0x01 + +#define ANALOG_I2C_NUM_LEVELS 32 /* 0..31 */ +#define ANALOG_I2C_REG_MASK 0x7c + +#define MP3309C_PWM_DEFAULT_NUM_LEVELS 256 /* 0..255 */ + +enum mp3309c_status_value { + FIRST_POWER_ON, + BACKLIGHT_OFF, + BACKLIGHT_ON, +}; + +enum mp3309c_dimming_mode_value { + DIMMING_PWM, + DIMMING_ANALOG_I2C, +}; + +struct mp3309c_platform_data { + unsigned int max_brightness; + unsigned int default_brightness; + unsigned int *levels; + u8 dimming_mode; + u8 over_voltage_protection; + bool sync_mode; + u8 status; +}; + +struct mp3309c_chip { + struct device *dev; + struct mp3309c_platform_data *pdata; + struct backlight_device *bl; + struct gpio_desc *enable_gpio; + struct regmap *regmap; + struct pwm_device *pwmd; +}; + +static const struct regmap_config mp3309c_regmap = { + .name = "mp3309c_regmap", + .reg_bits = 8, + .reg_stride = 1, + .val_bits = 8, + .max_register = REG_I2C_1, +}; + +static int mp3309c_enable_device(struct mp3309c_chip *chip) +{ + u8 reg_val; + int ret; + + /* I2C register #0 - Device enable */ + ret = regmap_update_bits(chip->regmap, REG_I2C_0, REG_I2C_0_EN, + REG_I2C_0_EN); + if (ret) + return ret; + + /* + * I2C register #1 - Set working mode: + * - set one of the two dimming mode: + * - PWM dimming using an external PWM dimming signal + * - analog dimming using I2C commands + * - enable/disable synchronous mode + * - set overvoltage protection (OVP) + */ + reg_val = 0x00; + if (chip->pdata->dimming_mode == DIMMING_PWM) + reg_val |= REG_I2C_1_DIMS; + if (chip->pdata->sync_mode) + reg_val |= REG_I2C_1_SYNC; + reg_val |= chip->pdata->over_voltage_protection; + ret = regmap_write(chip->regmap, REG_I2C_1, reg_val); + if (ret) + return ret; + + return 0; +} + +static int mp3309c_bl_update_status(struct backlight_device *bl) +{ + struct mp3309c_chip *chip = bl_get_data(bl); + int brightness = backlight_get_brightness(bl); + struct pwm_state pwmstate; + unsigned int analog_val, bits_val; + int i, ret; + + if (chip->pdata->dimming_mode == DIMMING_PWM) { + /* + * PWM control mode + */ + pwm_get_state(chip->pwmd, &pwmstate); + pwm_set_relative_duty_cycle(&pwmstate, + chip->pdata->levels[brightness], + chip->pdata->levels[chip->pdata->max_brightness]); + pwmstate.enabled = true; + ret = pwm_apply_state(chip->pwmd, &pwmstate); + if (ret) + return ret; + + switch (chip->pdata->status) { + case FIRST_POWER_ON: + case BACKLIGHT_OFF: + /* + * After 20ms of low pwm signal level, the chip turns + * off automatically. In this case, before enabling the + * chip again, we must wait about 10ms for pwm signal to + * stabilize. + */ + if (brightness > 0) { + msleep(10); + mp3309c_enable_device(chip); + chip->pdata->status = BACKLIGHT_ON; + } else { + chip->pdata->status = BACKLIGHT_OFF; + } + break; + case BACKLIGHT_ON: + if (brightness == 0) + chip->pdata->status = BACKLIGHT_OFF; + break; + } + } else { + /* + * Analog (by I2C command) control mode + * + * The first time, before setting brightness, we must enable the + * device + */ + if (chip->pdata->status == FIRST_POWER_ON) + mp3309c_enable_device(chip); + + /* + * Dimming mode I2C command (fixed dimming range 0..31) + * + * The 5 bits of the dimming analog value D4..D0 is allocated + * in the I2C register #0, in the following way: + * + * +--+--+--+--+--+--+--+--+ + * |EN|D0|D1|D2|D3|D4|XX|XX| + * +--+--+--+--+--+--+--+--+ + */ + analog_val = brightness; + bits_val = 0; + for (i = 0; i <= 5; i++) + bits_val += ((analog_val >> i) & 0x01) << (6 - i); + ret = regmap_update_bits(chip->regmap, REG_I2C_0, + ANALOG_I2C_REG_MASK, bits_val); + if (ret) + return ret; + + if (brightness > 0) + chip->pdata->status = BACKLIGHT_ON; + else + chip->pdata->status = BACKLIGHT_OFF; + } + + return 0; +} + +static const struct backlight_ops mp3309c_bl_ops = { + .update_status = mp3309c_bl_update_status, +}; + +static int pm3309c_parse_dt_node(struct mp3309c_chip *chip, + struct mp3309c_platform_data *pdata) +{ + struct device_node *node = chip->dev->of_node; + struct property *prop_pwms, *prop_levels; + int length = 0; + int ret, i; + unsigned int num_levels, tmp_value; + + if (!node) { + dev_err(chip->dev, "failed to get DT node\n"); + return -ENODEV; + } + + /* + * Dimming mode: the MP3309C provides two dimming control mode: + * + * - PWM mode + * - Analog by I2C control mode (default) + * + * I2C control mode is assumed as default but, if the pwms property is + * found in the backlight node, the mode switches to PWM mode. + */ + pdata->dimming_mode = DIMMING_ANALOG_I2C; + prop_pwms = of_find_property(node, "pwms", &length); + if (prop_pwms) { + chip->pwmd = devm_pwm_get(chip->dev, NULL); + if (IS_ERR(chip->pwmd)) + return dev_err_probe(chip->dev, PTR_ERR(chip->pwmd), + "error getting pwm data\n"); + pdata->dimming_mode = DIMMING_PWM; + pwm_apply_args(chip->pwmd); + } + + /* + * In I2C control mode the dimming levels (0..31) are fixed by the + * hardware, while in PWM control mode they can be chosen by the user, + * to allow nonlinear mappings. + */ + if (pdata->dimming_mode == DIMMING_ANALOG_I2C) { + /* + * Analog (by I2C commands) control mode: fixed 0..31 brightness + * levels + */ + num_levels = ANALOG_I2C_NUM_LEVELS; + + /* Enable GPIO used in I2C dimming mode only */ + chip->enable_gpio = devm_gpiod_get(chip->dev, "enable", + GPIOD_OUT_HIGH); + if (IS_ERR(chip->enable_gpio)) + return dev_err_probe(chip->dev, + PTR_ERR(chip->enable_gpio), + "error getting enable gpio\n"); + } else { + /* + * PWM control mode: check for brightness level in DT + */ + prop_levels = of_find_property(node, "brightness-levels", + &length); + if (prop_levels) { + /* Read brightness levels from DT */ + num_levels = length / sizeof(u32); + if (num_levels < 2) + return -EINVAL; + } else { + /* Use default brightness levels */ + num_levels = MP3309C_PWM_DEFAULT_NUM_LEVELS; + } + } + + /* Fill brightness levels array */ + pdata->levels = devm_kcalloc(chip->dev, num_levels, + sizeof(*pdata->levels), GFP_KERNEL); + if (!pdata->levels) + return -ENOMEM; + if (prop_levels) { + ret = of_property_read_u32_array(node, "brightness-levels", + pdata->levels, + num_levels); + if (ret < 0) + return ret; + } else { + for (i = 0; i < num_levels; i++) + pdata->levels[i] = i; + } + + pdata->max_brightness = num_levels - 1; + + ret = of_property_read_u32(node, "default-brightness", + &pdata->default_brightness); + if (ret) + pdata->default_brightness = pdata->max_brightness; + if (pdata->default_brightness > pdata->max_brightness) { + dev_err(chip->dev, + "default brightness exceeds max brightness\n"); + pdata->default_brightness = pdata->max_brightness; + } + + /* + * Over-voltage protection (OVP) + * + * This (optional) property values are: + * + * - 13.5V + * - 24V + * - 35.5V (hardware default setting) + * + * If missing, the default value for OVP is 35.5V + */ + pdata->over_voltage_protection = REG_I2C_1_OVP1; + if (!of_property_read_u32(node, "mps,overvoltage-protection-microvolt", + &tmp_value)) { + switch (tmp_value) { + case 13500000: + pdata->over_voltage_protection = 0x00; + break; + case 24000000: + pdata->over_voltage_protection = REG_I2C_1_OVP0; + break; + case 35500000: + pdata->over_voltage_protection = REG_I2C_1_OVP1; + break; + default: + return -EINVAL; + } + } + + /* Synchronous (default) and non-synchronous mode */ + pdata->sync_mode = true; + if (of_property_read_bool(node, "mps,no-sync-mode")) + pdata->sync_mode = false; + + return 0; +} + +static int mp3309c_probe(struct i2c_client *client) +{ + struct mp3309c_platform_data *pdata = dev_get_platdata(&client->dev); + struct mp3309c_chip *chip; + struct backlight_properties props; + struct pwm_state pwmstate; + int ret; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + dev_err(&client->dev, "failed to check i2c functionality\n"); + return -EOPNOTSUPP; + } + + chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + chip->dev = &client->dev; + + chip->regmap = devm_regmap_init_i2c(client, &mp3309c_regmap); + if (IS_ERR(chip->regmap)) + return dev_err_probe(&client->dev, PTR_ERR(chip->regmap), + "failed to allocate register map\n"); + + i2c_set_clientdata(client, chip); + + if (!pdata) { + pdata = devm_kzalloc(chip->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return -ENOMEM; + + ret = pm3309c_parse_dt_node(chip, pdata); + if (ret) + return ret; + } + chip->pdata = pdata; + + /* Backlight properties */ + props.brightness = pdata->default_brightness; + props.max_brightness = pdata->max_brightness; + props.scale = BACKLIGHT_SCALE_LINEAR; + props.type = BACKLIGHT_RAW; + props.power = FB_BLANK_UNBLANK; + props.fb_blank = FB_BLANK_UNBLANK; + chip->bl = devm_backlight_device_register(chip->dev, "mp3309c", + chip->dev, chip, + &mp3309c_bl_ops, &props); + if (IS_ERR(chip->bl)) + return dev_err_probe(chip->dev, PTR_ERR(chip->bl), + "error registering backlight device\n"); + + /* In PWM dimming mode, enable pwm device */ + if (chip->pdata->dimming_mode == DIMMING_PWM) { + pwm_init_state(chip->pwmd, &pwmstate); + pwm_set_relative_duty_cycle(&pwmstate, + chip->pdata->default_brightness, + chip->pdata->max_brightness); + pwmstate.enabled = true; + ret = pwm_apply_state(chip->pwmd, &pwmstate); + if (ret) + return dev_err_probe(chip->dev, ret, + "error setting pwm device\n"); + } + + chip->pdata->status = FIRST_POWER_ON; + backlight_update_status(chip->bl); + + return 0; +} + +static void mp3309c_remove(struct i2c_client *client) +{ + struct mp3309c_chip *chip = i2c_get_clientdata(client); + struct backlight_device *bl = chip->bl; + + bl->props.power = FB_BLANK_POWERDOWN; + bl->props.brightness = 0; + backlight_update_status(chip->bl); +} + +static const struct of_device_id mp3309c_match_table[] = { + { .compatible = "mps,mp3309c", }, + { }, +}; +MODULE_DEVICE_TABLE(of, mp3309c_match_table); + +static const struct i2c_device_id mp3309c_id[] = { + { "mp3309c", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, mp3309c_id); + +static struct i2c_driver mp3309c_i2c_driver = { + .driver = { + .name = KBUILD_MODNAME, + .of_match_table = mp3309c_match_table, + }, + .probe = mp3309c_probe, + .remove = mp3309c_remove, + .id_table = mp3309c_id, +}; + +module_i2c_driver(mp3309c_i2c_driver); + +MODULE_DESCRIPTION("Backlight Driver for MPS MP3309C"); +MODULE_AUTHOR("Flavio Suligoi "); +MODULE_LICENSE("GPL"); From 58793f263abc8e5233fabf7466219202db09d048 Mon Sep 17 00:00:00 2001 From: Alexander Stein Date: Fri, 17 Nov 2023 13:06:25 +0100 Subject: [PATCH 3/7] backlight: pwm_bl: Use dev_err_probe MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Use dev_err_probe to simplify error paths. Also let dev_err_probe handle the -EPROBE_DEFER case and add an entry to /sys/kernel/debug/devices_deferred when deferred. Signed-off-by: Alexander Stein Reviewed-by: Uwe Kleine-König Reviewed-by: Daniel Thompson Link: https://lore.kernel.org/r/20231117120625.2398417-1-alexander.stein@ew.tq-group.com Signed-off-by: Lee Jones --- drivers/video/backlight/pwm_bl.c | 34 +++++++++++++++++--------------- 1 file changed, 18 insertions(+), 16 deletions(-) diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index 289bd9ce4d36..5bc9c6c07571 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -461,10 +461,9 @@ static int pwm_backlight_probe(struct platform_device *pdev) if (!data) { ret = pwm_backlight_parse_dt(&pdev->dev, &defdata); - if (ret < 0) { - dev_err(&pdev->dev, "failed to find platform data\n"); - return ret; - } + if (ret < 0) + return dev_err_probe(&pdev->dev, ret, + "failed to find platform data\n"); data = &defdata; } @@ -493,24 +492,27 @@ static int pwm_backlight_probe(struct platform_device *pdev) pb->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable", GPIOD_ASIS); if (IS_ERR(pb->enable_gpio)) { - ret = PTR_ERR(pb->enable_gpio); + ret = dev_err_probe(&pdev->dev, PTR_ERR(pb->enable_gpio), + "failed to acquire enable GPIO\n"); goto err_alloc; } pb->power_supply = devm_regulator_get_optional(&pdev->dev, "power"); if (IS_ERR(pb->power_supply)) { ret = PTR_ERR(pb->power_supply); - if (ret == -ENODEV) + if (ret == -ENODEV) { pb->power_supply = NULL; - else + } else { + dev_err_probe(&pdev->dev, ret, + "failed to acquire power regulator\n"); goto err_alloc; + } } pb->pwm = devm_pwm_get(&pdev->dev, NULL); if (IS_ERR(pb->pwm)) { - ret = PTR_ERR(pb->pwm); - if (ret != -EPROBE_DEFER) - dev_err(&pdev->dev, "unable to request PWM\n"); + ret = dev_err_probe(&pdev->dev, PTR_ERR(pb->pwm), + "unable to request PWM\n"); goto err_alloc; } @@ -530,8 +532,8 @@ static int pwm_backlight_probe(struct platform_device *pdev) ret = pwm_apply_state(pb->pwm, &state); if (ret) { - dev_err(&pdev->dev, "failed to apply initial PWM state: %d\n", - ret); + dev_err_probe(&pdev->dev, ret, + "failed to apply initial PWM state"); goto err_alloc; } @@ -568,8 +570,8 @@ static int pwm_backlight_probe(struct platform_device *pdev) ret = pwm_backlight_brightness_default(&pdev->dev, data, state.period); if (ret < 0) { - dev_err(&pdev->dev, - "failed to setup default brightness table\n"); + dev_err_probe(&pdev->dev, ret, + "failed to setup default brightness table\n"); goto err_alloc; } @@ -597,8 +599,8 @@ static int pwm_backlight_probe(struct platform_device *pdev) bl = backlight_device_register(dev_name(&pdev->dev), &pdev->dev, pb, &pwm_backlight_ops, &props); if (IS_ERR(bl)) { - dev_err(&pdev->dev, "failed to register backlight\n"); - ret = PTR_ERR(bl); + ret = dev_err_probe(&pdev->dev, PTR_ERR(bl), + "failed to register backlight\n"); goto err_alloc; } From ab47505ce45b869ab649024dc932e981fcdd6e5f Mon Sep 17 00:00:00 2001 From: Flavio Suligoi Date: Wed, 29 Nov 2023 17:45:14 +0100 Subject: [PATCH 4/7] backlight: mp3309c: Fix uninitialized local variable In the function "pm3309c_parse_dt_node", when the dimming analog control mode (by I2C messages) is enabled, the local variable "prop_levels" is tested without any initialization, as indicated by the following smatch warning: drivers/video/backlight/mp3309c.c:279 pm3309c_parse_dt_node() error: uninitialized symbol 'prop_levels'. To avoid any problem in case of undefined behavior, we need to initialize it to "NULL". Reported-by: Dan Carpenter Closes: https://lore.kernel.org/dri-devel/af0a1870-693b-442f-9b11-0503cfcd944a@moroto.mountain/ Fixes: 2e914516a58c ("backlight: mp3309c: Add support for MPS MP3309C") Signed-off-by: Flavio Suligoi Reviewed-by: Daniel Thompson Link: https://lore.kernel.org/r/20231129164514.2772719-1-f.suligoi@asem.it Signed-off-by: Lee Jones --- drivers/video/backlight/mp3309c.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/video/backlight/mp3309c.c b/drivers/video/backlight/mp3309c.c index 3fe4469ef43f..34d71259fac1 100644 --- a/drivers/video/backlight/mp3309c.c +++ b/drivers/video/backlight/mp3309c.c @@ -203,7 +203,8 @@ static int pm3309c_parse_dt_node(struct mp3309c_chip *chip, struct mp3309c_platform_data *pdata) { struct device_node *node = chip->dev->of_node; - struct property *prop_pwms, *prop_levels; + struct property *prop_pwms; + struct property *prop_levels = NULL; int length = 0; int ret, i; unsigned int num_levels, tmp_value; From 64d9799d6dd04601227f602ae961e3f3d2f1f02b Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Wed, 6 Dec 2023 09:45:25 -0800 Subject: [PATCH 5/7] backlight: ili922x: Drop kernel-doc for local macros Don't use kernel-doc notation for the local macros START_BYTE() and CHECK_FREQ_REG(). This prevents these kernel-doc warnings: ili922x.c:85: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * START_BYTE(id, rs, rw) ili922x.c:85: warning: missing initial short description on line: * START_BYTE(id, rs, rw) ili922x.c:118: warning: expecting prototype for CHECK_FREQ_REG(spi_device s, spi_transfer x)(). Prototype was for CHECK_FREQ_REG() instead Signed-off-by: Randy Dunlap Reviewed-by: Daniel Thompson Link: https://lore.kernel.org/r/20231206174525.14960-1-rdunlap@infradead.org Signed-off-by: Lee Jones --- drivers/video/backlight/ili922x.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/video/backlight/ili922x.c b/drivers/video/backlight/ili922x.c index e7b6bd827986..206e77afc56f 100644 --- a/drivers/video/backlight/ili922x.c +++ b/drivers/video/backlight/ili922x.c @@ -81,7 +81,7 @@ #define START_RW_WRITE 0 #define START_RW_READ 1 -/** +/* * START_BYTE(id, rs, rw) * * Set the start byte according to the required operation. @@ -100,7 +100,7 @@ #define START_BYTE(id, rs, rw) \ (0x70 | (((id) & 0x01) << 2) | (((rs) & 0x01) << 1) | ((rw) & 0x01)) -/** +/* * CHECK_FREQ_REG(spi_device s, spi_transfer x) - Check the frequency * for the SPI transfer. According to the datasheet, the controller * accept higher frequency for the GRAM transfer, but it requires From 769ff5283f0d7edc819743f183d51af077411107 Mon Sep 17 00:00:00 2001 From: Su Hui Date: Thu, 30 Nov 2023 13:11:56 +0800 Subject: [PATCH 6/7] backlight: ili922x: Add an error code check in ili922x_write() Clang static analyzer complains that value stored to 'ret' is never read. Return the error code when spi_sync() failed. Signed-off-by: Su Hui Reviewed-by: Daniel Thompson Link: https://lore.kernel.org/r/20231130051155.1235972-1-suhui@nfschina.com Signed-off-by: Lee Jones --- drivers/video/backlight/ili922x.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/video/backlight/ili922x.c b/drivers/video/backlight/ili922x.c index 206e77afc56f..c8e0e655dc86 100644 --- a/drivers/video/backlight/ili922x.c +++ b/drivers/video/backlight/ili922x.c @@ -269,6 +269,10 @@ static int ili922x_write(struct spi_device *spi, u8 reg, u16 value) spi_message_add_tail(&xfer_regindex, &msg); ret = spi_sync(spi, &msg); + if (ret < 0) { + dev_err(&spi->dev, "Error sending SPI message 0x%x", ret); + return ret; + } spi_message_init(&msg); tbuf[0] = set_tx_byte(START_BYTE(ili922x_id, START_RS_REG, From 7d84a63a39b78443d09f2b4edf7ecb1d586379b4 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Thu, 7 Dec 2023 18:14:32 +0200 Subject: [PATCH 7/7] backlight: hx8357: Convert to agnostic GPIO API The of_gpio.h is going to be removed. In preparation of that convert the driver to the agnostic API. Fixes: fbbbcd177a27 ("gpiolib: of: add quirk for locating reset lines with legacy bindings") Signed-off-by: Andy Shevchenko Reviewed-by: Daniel Thompson Reviewed-by: Linus Walleij Link: https://lore.kernel.org/r/20231207161513.3195509-2-andriy.shevchenko@linux.intel.com Signed-off-by: Lee Jones --- drivers/gpio/gpiolib-of.c | 4 +- drivers/video/backlight/hx8357.c | 74 ++++++++++---------------------- 2 files changed, 24 insertions(+), 54 deletions(-) diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index 402f7d99b0c1..e7770eedd146 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -184,7 +184,7 @@ static void of_gpio_try_fixup_polarity(const struct device_node *np, const char *propname; bool active_high; } gpios[] = { -#if !IS_ENABLED(CONFIG_LCD_HX8357) +#if IS_ENABLED(CONFIG_LCD_HX8357) /* * Himax LCD controllers used incorrectly named * "gpios-reset" property and also specified wrong @@ -478,7 +478,7 @@ static struct gpio_desc *of_find_gpio_rename(struct device_node *np, */ const char *compatible; } gpios[] = { -#if !IS_ENABLED(CONFIG_LCD_HX8357) +#if IS_ENABLED(CONFIG_LCD_HX8357) /* Himax LCD controllers used "gpios-reset" */ { "reset", "gpios-reset", "himax,hx8357" }, { "reset", "gpios-reset", "himax,hx8369" }, diff --git a/drivers/video/backlight/hx8357.c b/drivers/video/backlight/hx8357.c index f76d2469d490..d7298376cf74 100644 --- a/drivers/video/backlight/hx8357.c +++ b/drivers/video/backlight/hx8357.c @@ -6,11 +6,11 @@ */ #include +#include #include #include #include #include -#include #include #define HX8357_NUM_IM_PINS 3 @@ -83,11 +83,10 @@ #define HX8369_SET_GAMMA_CURVE_RELATED 0xe0 struct hx8357_data { - unsigned im_pins[HX8357_NUM_IM_PINS]; - unsigned reset; + struct gpio_descs *im_pins; + struct gpio_desc *reset; struct spi_device *spi; int state; - bool use_im_pins; }; static u8 hx8357_seq_power[] = { @@ -321,11 +320,11 @@ static void hx8357_lcd_reset(struct lcd_device *lcdev) struct hx8357_data *lcd = lcd_get_data(lcdev); /* Reset the screen */ - gpio_set_value(lcd->reset, 1); + gpiod_set_value(lcd->reset, 0); usleep_range(10000, 12000); - gpio_set_value(lcd->reset, 0); + gpiod_set_value(lcd->reset, 1); usleep_range(10000, 12000); - gpio_set_value(lcd->reset, 1); + gpiod_set_value(lcd->reset, 0); /* The controller needs 120ms to recover from reset */ msleep(120); @@ -340,10 +339,10 @@ static int hx8357_lcd_init(struct lcd_device *lcdev) * Set the interface selection pins to SPI mode, with three * wires */ - if (lcd->use_im_pins) { - gpio_set_value_cansleep(lcd->im_pins[0], 1); - gpio_set_value_cansleep(lcd->im_pins[1], 0); - gpio_set_value_cansleep(lcd->im_pins[2], 1); + if (lcd->im_pins) { + gpiod_set_value_cansleep(lcd->im_pins->desc[0], 1); + gpiod_set_value_cansleep(lcd->im_pins->desc[1], 0); + gpiod_set_value_cansleep(lcd->im_pins->desc[2], 1); } ret = hx8357_spi_write_array(lcdev, hx8357_seq_power, @@ -580,6 +579,7 @@ MODULE_DEVICE_TABLE(of, hx8357_dt_ids); static int hx8357_probe(struct spi_device *spi) { + struct device *dev = &spi->dev; struct lcd_device *lcdev; struct hx8357_data *lcd; const struct of_device_id *match; @@ -601,49 +601,19 @@ static int hx8357_probe(struct spi_device *spi) if (!match || !match->data) return -EINVAL; - lcd->reset = of_get_named_gpio(spi->dev.of_node, "gpios-reset", 0); - if (!gpio_is_valid(lcd->reset)) { - dev_err(&spi->dev, "Missing dt property: gpios-reset\n"); - return -EINVAL; - } + lcd->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW); + if (IS_ERR(lcd->reset)) + return dev_err_probe(dev, PTR_ERR(lcd->reset), "failed to request reset GPIO\n"); + gpiod_set_consumer_name(lcd->reset, "hx8357-reset"); - ret = devm_gpio_request_one(&spi->dev, lcd->reset, - GPIOF_OUT_INIT_HIGH, - "hx8357-reset"); - if (ret) { - dev_err(&spi->dev, - "failed to request gpio %d: %d\n", - lcd->reset, ret); - return -EINVAL; - } + lcd->im_pins = devm_gpiod_get_array_optional(dev, "im", GPIOD_OUT_LOW); + if (IS_ERR(lcd->im_pins)) + return dev_err_probe(dev, PTR_ERR(lcd->im_pins), "failed to request im GPIOs\n"); + if (lcd->im_pins->ndescs < HX8357_NUM_IM_PINS) + return dev_err_probe(dev, -EINVAL, "not enough im GPIOs\n"); - if (of_property_present(spi->dev.of_node, "im-gpios")) { - lcd->use_im_pins = 1; - - for (i = 0; i < HX8357_NUM_IM_PINS; i++) { - lcd->im_pins[i] = of_get_named_gpio(spi->dev.of_node, - "im-gpios", i); - if (lcd->im_pins[i] == -EPROBE_DEFER) { - dev_info(&spi->dev, "GPIO requested is not here yet, deferring the probe\n"); - return -EPROBE_DEFER; - } - if (!gpio_is_valid(lcd->im_pins[i])) { - dev_err(&spi->dev, "Missing dt property: im-gpios\n"); - return -EINVAL; - } - - ret = devm_gpio_request_one(&spi->dev, lcd->im_pins[i], - GPIOF_OUT_INIT_LOW, - "im_pins"); - if (ret) { - dev_err(&spi->dev, "failed to request gpio %d: %d\n", - lcd->im_pins[i], ret); - return -EINVAL; - } - } - } else { - lcd->use_im_pins = 0; - } + for (i = 0; i < HX8357_NUM_IM_PINS; i++) + gpiod_set_consumer_name(lcd->im_pins->desc[i], "im_pins"); lcdev = devm_lcd_device_register(&spi->dev, "mxsfb", &spi->dev, lcd, &hx8357_ops);