// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) 2023 Richtek Technology Corp. * * Authors: * Alice Chen * ChiYuan Huang */ #include #include #include #include #include #include #include #include #include #include #include #include enum { MT6370_LED_FLASH1 = 0, MT6370_LED_FLASH2, MT6370_MAX_LEDS }; /* Virtual definition for multicolor */ #define MT6370_REG_FLEDEN 0x17E #define MT6370_REG_STRBTO 0x173 #define MT6370_REG_CHGSTAT2 0x1D1 #define MT6370_REG_FLEDSTAT1 0x1D9 #define MT6370_REG_FLEDISTRB(_id) (0x174 + 4 * (_id)) #define MT6370_REG_FLEDITOR(_id) (0x175 + 4 * (_id)) #define MT6370_ITORCH_MASK GENMASK(4, 0) #define MT6370_ISTROBE_MASK GENMASK(6, 0) #define MT6370_STRBTO_MASK GENMASK(6, 0) #define MT6370_TORCHEN_MASK BIT(3) #define MT6370_STROBEN_MASK BIT(2) #define MT6370_FLCSEN_MASK(_id) BIT(MT6370_LED_FLASH2 - (_id)) #define MT6370_FLCSEN_MASK_ALL GENMASK(1, 0) #define MT6370_FLEDCHGVINOVP_MASK BIT(3) #define MT6370_FLED1STRBTO_MASK BIT(11) #define MT6370_FLED2STRBTO_MASK BIT(10) #define MT6370_FLED1STRB_MASK BIT(9) #define MT6370_FLED2STRB_MASK BIT(8) #define MT6370_FLED1SHORT_MASK BIT(7) #define MT6370_FLED2SHORT_MASK BIT(6) #define MT6370_FLEDLVF_MASK BIT(3) #define MT6370_LED_JOINT 2 #define MT6370_RANGE_FLED_REG 4 #define MT6370_ITORCH_MIN_uA 25000 #define MT6370_ITORCH_STEP_uA 12500 #define MT6370_ITORCH_MAX_uA 400000 #define MT6370_ITORCH_DOUBLE_MAX_uA 800000 #define MT6370_ISTRB_MIN_uA 50000 #define MT6370_ISTRB_STEP_uA 12500 #define MT6370_ISTRB_MAX_uA 1500000 #define MT6370_ISTRB_DOUBLE_MAX_uA 3000000 #define MT6370_STRBTO_MIN_US 64000 #define MT6370_STRBTO_STEP_US 32000 #define MT6370_STRBTO_MAX_US 2432000 #define to_mt6370_led(ptr, member) container_of(ptr, struct mt6370_led, member) struct mt6370_led { struct led_classdev_flash flash; struct v4l2_flash *v4l2_flash; struct mt6370_priv *priv; u8 led_no; }; struct mt6370_priv { struct regmap *regmap; struct mutex lock; unsigned int fled_strobe_used; unsigned int fled_torch_used; unsigned int leds_active; unsigned int leds_count; struct mt6370_led leds[] __counted_by(leds_count); }; static int mt6370_torch_brightness_set(struct led_classdev *lcdev, enum led_brightness level) { struct mt6370_led *led = to_mt6370_led(lcdev, flash.led_cdev); struct mt6370_priv *priv = led->priv; u32 led_enable_mask = led->led_no == MT6370_LED_JOINT ? MT6370_FLCSEN_MASK_ALL : MT6370_FLCSEN_MASK(led->led_no); u32 enable_mask = MT6370_TORCHEN_MASK | led_enable_mask; u32 val = level ? led_enable_mask : 0; u32 curr; int ret, i; mutex_lock(&priv->lock); /* * There is only one set of flash control logic, and this flag is used to check if 'strobe' * is currently being used. */ if (priv->fled_strobe_used) { dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used); ret = -EBUSY; goto unlock; } if (level) curr = priv->fled_torch_used | BIT(led->led_no); else curr = priv->fled_torch_used & ~BIT(led->led_no); if (curr) val |= MT6370_TORCHEN_MASK; if (level) { level -= 1; if (led->led_no == MT6370_LED_JOINT) { u32 flevel[MT6370_MAX_LEDS]; /* * There're two flash channels in MT6370. If joint flash output is used, * torch current will be averaged output from both channels. */ flevel[0] = level / 2; flevel[1] = level - flevel[0]; for (i = 0; i < MT6370_MAX_LEDS; i++) { ret = regmap_update_bits(priv->regmap, MT6370_REG_FLEDITOR(i), MT6370_ITORCH_MASK, flevel[i]); if (ret) goto unlock; } } else { ret = regmap_update_bits(priv->regmap, MT6370_REG_FLEDITOR(led->led_no), MT6370_ITORCH_MASK, level); if (ret) goto unlock; } } ret = regmap_update_bits(priv->regmap, MT6370_REG_FLEDEN, enable_mask, val); if (ret) goto unlock; priv->fled_torch_used = curr; unlock: mutex_unlock(&priv->lock); return ret; } static int mt6370_flash_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness) { /* * Because of the current spikes when turning on the flash, the brightness should be kept * by the LED framework. This empty function is used to prevent checking failure when * led_classdev_flash registers ops. */ return 0; } static int _mt6370_flash_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness) { struct mt6370_led *led = to_mt6370_led(fl_cdev, flash); struct mt6370_priv *priv = led->priv; struct led_flash_setting *setting = &fl_cdev->brightness; u32 val = (brightness - setting->min) / setting->step; int ret, i; if (led->led_no == MT6370_LED_JOINT) { u32 flevel[MT6370_MAX_LEDS]; /* * There're two flash channels in MT6370. If joint flash output is used, storbe * current will be averaged output from both channels. */ flevel[0] = val / 2; flevel[1] = val - flevel[0]; for (i = 0; i < MT6370_MAX_LEDS; i++) { ret = regmap_update_bits(priv->regmap, MT6370_REG_FLEDISTRB(i), MT6370_ISTROBE_MASK, flevel[i]); if (ret) break; } } else { ret = regmap_update_bits(priv->regmap, MT6370_REG_FLEDISTRB(led->led_no), MT6370_ISTROBE_MASK, val); } return ret; } static int mt6370_strobe_set(struct led_classdev_flash *fl_cdev, bool state) { struct mt6370_led *led = to_mt6370_led(fl_cdev, flash); struct mt6370_priv *priv = led->priv; struct led_classdev *lcdev = &fl_cdev->led_cdev; struct led_flash_setting *s = &fl_cdev->brightness; u32 led_enable_mask = led->led_no == MT6370_LED_JOINT ? MT6370_FLCSEN_MASK_ALL : MT6370_FLCSEN_MASK(led->led_no); u32 enable_mask = MT6370_STROBEN_MASK | led_enable_mask; u32 val = state ? led_enable_mask : 0; u32 curr; int ret; mutex_lock(&priv->lock); /* * There is only one set of flash control logic, and this flag is used to check if 'torch' * is currently being used. */ if (priv->fled_torch_used) { dev_warn(lcdev->dev, "Please disable torch first [0x%x]\n", priv->fled_torch_used); ret = -EBUSY; goto unlock; } if (state) curr = priv->fled_strobe_used | BIT(led->led_no); else curr = priv->fled_strobe_used & ~BIT(led->led_no); if (curr) val |= MT6370_STROBEN_MASK; ret = regmap_update_bits(priv->regmap, MT6370_REG_FLEDEN, enable_mask, val); if (ret) { dev_err(lcdev->dev, "[%d] control current source %d fail\n", led->led_no, state); goto unlock; } /* * If the flash needs to turn on, configure the flash current to ramp up to the setting * value. Otherwise, always revert to the minimum one. */ ret = _mt6370_flash_brightness_set(fl_cdev, state ? s->val : s->min); if (ret) { dev_err(lcdev->dev, "[%d] Failed to set brightness\n", led->led_no); goto unlock; } /* * For the flash to turn on/off, we must wait for HW ramping up/down time 5ms/500us to * prevent the unexpected problem. */ if (!priv->fled_strobe_used && curr) usleep_range(5000, 6000); else if (priv->fled_strobe_used && !curr) usleep_range(500, 600); priv->fled_strobe_used = curr; unlock: mutex_unlock(&priv->lock); return ret; } static int mt6370_strobe_get(struct led_classdev_flash *fl_cdev, bool *state) { struct mt6370_led *led = to_mt6370_led(fl_cdev, flash); struct mt6370_priv *priv = led->priv; mutex_lock(&priv->lock); *state = !!(priv->fled_strobe_used & BIT(led->led_no)); mutex_unlock(&priv->lock); return 0; } static int mt6370_timeout_set(struct led_classdev_flash *fl_cdev, u32 timeout) { struct mt6370_led *led = to_mt6370_led(fl_cdev, flash); struct mt6370_priv *priv = led->priv; struct led_flash_setting *s = &fl_cdev->timeout; u32 val = (timeout - s->min) / s->step; return regmap_update_bits(priv->regmap, MT6370_REG_STRBTO, MT6370_STRBTO_MASK, val); } static int mt6370_fault_get(struct led_classdev_flash *fl_cdev, u32 *fault) { struct mt6370_led *led = to_mt6370_led(fl_cdev, flash); struct mt6370_priv *priv = led->priv; u16 fled_stat; unsigned int chg_stat, strobe_timeout_mask, fled_short_mask; u32 rfault = 0; int ret; ret = regmap_read(priv->regmap, MT6370_REG_CHGSTAT2, &chg_stat); if (ret) return ret; ret = regmap_raw_read(priv->regmap, MT6370_REG_FLEDSTAT1, &fled_stat, sizeof(fled_stat)); if (ret) return ret; switch (led->led_no) { case MT6370_LED_FLASH1: strobe_timeout_mask = MT6370_FLED1STRBTO_MASK; fled_short_mask = MT6370_FLED1SHORT_MASK; break; case MT6370_LED_FLASH2: strobe_timeout_mask = MT6370_FLED2STRBTO_MASK; fled_short_mask = MT6370_FLED2SHORT_MASK; break; case MT6370_LED_JOINT: strobe_timeout_mask = MT6370_FLED1STRBTO_MASK | MT6370_FLED2STRBTO_MASK; fled_short_mask = MT6370_FLED1SHORT_MASK | MT6370_FLED2SHORT_MASK; break; default: return -EINVAL; } if (chg_stat & MT6370_FLEDCHGVINOVP_MASK) rfault |= LED_FAULT_INPUT_VOLTAGE; if (fled_stat & strobe_timeout_mask) rfault |= LED_FAULT_TIMEOUT; if (fled_stat & fled_short_mask) rfault |= LED_FAULT_SHORT_CIRCUIT; if (fled_stat & MT6370_FLEDLVF_MASK) rfault |= LED_FAULT_UNDER_VOLTAGE; *fault = rfault; return ret; } static const struct led_flash_ops mt6370_flash_ops = { .flash_brightness_set = mt6370_flash_brightness_set, .strobe_set = mt6370_strobe_set, .strobe_get = mt6370_strobe_get, .timeout_set = mt6370_timeout_set, .fault_get = mt6370_fault_get, }; #if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS) static int mt6370_flash_external_strobe_set(struct v4l2_flash *v4l2_flash, bool enable) { struct led_classdev_flash *flash = v4l2_flash->fled_cdev; struct mt6370_led *led = to_mt6370_led(flash, flash); struct mt6370_priv *priv = led->priv; u32 mask = led->led_no == MT6370_LED_JOINT ? MT6370_FLCSEN_MASK_ALL : MT6370_FLCSEN_MASK(led->led_no); u32 val = enable ? mask : 0; int ret; mutex_lock(&priv->lock); ret = regmap_update_bits(priv->regmap, MT6370_REG_FLEDEN, mask, val); if (ret) goto unlock; if (enable) priv->fled_strobe_used |= BIT(led->led_no); else priv->fled_strobe_used &= ~BIT(led->led_no); unlock: mutex_unlock(&priv->lock); return ret; } static const struct v4l2_flash_ops v4l2_flash_ops = { .external_strobe_set = mt6370_flash_external_strobe_set, }; static void mt6370_init_v4l2_flash_config(struct mt6370_led *led, struct v4l2_flash_config *cfg) { struct led_classdev *lcdev; struct led_flash_setting *s = &cfg->intensity; lcdev = &led->flash.led_cdev; s->min = MT6370_ITORCH_MIN_uA; s->step = MT6370_ITORCH_STEP_uA; s->val = s->max = s->min + (lcdev->max_brightness - 1) * s->step; cfg->has_external_strobe = 1; strscpy(cfg->dev_name, dev_name(lcdev->dev), sizeof(cfg->dev_name)); cfg->flash_faults = LED_FAULT_SHORT_CIRCUIT | LED_FAULT_TIMEOUT | LED_FAULT_INPUT_VOLTAGE | LED_FAULT_UNDER_VOLTAGE; } #else static const struct v4l2_flash_ops v4l2_flash_ops; static void mt6370_init_v4l2_flash_config(struct mt6370_led *led, struct v4l2_flash_config *cfg) { } #endif static void mt6370_v4l2_flash_release(void *v4l2_flash) { v4l2_flash_release(v4l2_flash); } static int mt6370_led_register(struct device *parent, struct mt6370_led *led, struct fwnode_handle *fwnode) { struct led_init_data init_data = { .fwnode = fwnode }; struct v4l2_flash_config v4l2_config = {}; int ret; ret = devm_led_classdev_flash_register_ext(parent, &led->flash, &init_data); if (ret) return dev_err_probe(parent, ret, "Couldn't register flash %d\n", led->led_no); mt6370_init_v4l2_flash_config(led, &v4l2_config); led->v4l2_flash = v4l2_flash_init(parent, fwnode, &led->flash, &v4l2_flash_ops, &v4l2_config); if (IS_ERR(led->v4l2_flash)) return dev_err_probe(parent, PTR_ERR(led->v4l2_flash), "Failed to register %d v4l2 sd\n", led->led_no); return devm_add_action_or_reset(parent, mt6370_v4l2_flash_release, led->v4l2_flash); } static u32 mt6370_clamp(u32 val, u32 min, u32 max, u32 step) { u32 retval; retval = clamp_val(val, min, max); if (step > 1) retval = rounddown(retval - min, step) + min; return retval; } static int mt6370_init_flash_properties(struct device *dev, struct mt6370_led *led, struct fwnode_handle *fwnode) { struct led_classdev_flash *flash = &led->flash; struct led_classdev *lcdev = &flash->led_cdev; struct mt6370_priv *priv = led->priv; struct led_flash_setting *s; u32 sources[MT6370_MAX_LEDS]; u32 max_ua, val; int i, ret, num; num = fwnode_property_count_u32(fwnode, "led-sources"); if (num < 1) return dev_err_probe(dev, -EINVAL, "Not specified or wrong number of led-sources\n"); ret = fwnode_property_read_u32_array(fwnode, "led-sources", sources, num); if (ret) return ret; for (i = 0; i < num; i++) { if (sources[i] >= MT6370_MAX_LEDS) return -EINVAL; if (priv->leds_active & BIT(sources[i])) return -EINVAL; priv->leds_active |= BIT(sources[i]); } /* If both channels are specified in 'led-sources', joint flash output mode is used */ led->led_no = num == 2 ? MT6370_LED_JOINT : sources[0]; max_ua = num == 2 ? MT6370_ITORCH_DOUBLE_MAX_uA : MT6370_ITORCH_MAX_uA; val = MT6370_ITORCH_MIN_uA; ret = fwnode_property_read_u32(fwnode, "led-max-microamp", &val); if (!ret) val = mt6370_clamp(val, MT6370_ITORCH_MIN_uA, max_ua, MT6370_ITORCH_STEP_uA); lcdev->max_brightness = (val - MT6370_ITORCH_MIN_uA) / MT6370_ITORCH_STEP_uA + 1; lcdev->brightness_set_blocking = mt6370_torch_brightness_set; lcdev->flags |= LED_DEV_CAP_FLASH; max_ua = num == 2 ? MT6370_ISTRB_DOUBLE_MAX_uA : MT6370_ISTRB_MAX_uA; val = MT6370_ISTRB_MIN_uA; ret = fwnode_property_read_u32(fwnode, "flash-max-microamp", &val); if (!ret) val = mt6370_clamp(val, MT6370_ISTRB_MIN_uA, max_ua, MT6370_ISTRB_STEP_uA); s = &flash->brightness; s->min = MT6370_ISTRB_MIN_uA; s->step = MT6370_ISTRB_STEP_uA; s->val = s->max = val; /* Always configure to the minimum level when off to prevent flash current spikes. */ ret = _mt6370_flash_brightness_set(flash, s->min); if (ret) return ret; val = MT6370_STRBTO_MIN_US; ret = fwnode_property_read_u32(fwnode, "flash-max-timeout-us", &val); if (!ret) val = mt6370_clamp(val, MT6370_STRBTO_MIN_US, MT6370_STRBTO_MAX_US, MT6370_STRBTO_STEP_US); s = &flash->timeout; s->min = MT6370_STRBTO_MIN_US; s->step = MT6370_STRBTO_STEP_US; s->val = s->max = val; flash->ops = &mt6370_flash_ops; return 0; } static int mt6370_led_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct mt6370_priv *priv; struct fwnode_handle *child; size_t count; int i = 0, ret; count = device_get_child_node_count(dev); if (!count || count > MT6370_MAX_LEDS) return dev_err_probe(dev, -EINVAL, "No child node or node count over max led number %zu\n", count); priv = devm_kzalloc(dev, struct_size(priv, leds, count), GFP_KERNEL); if (!priv) return -ENOMEM; priv->leds_count = count; mutex_init(&priv->lock); priv->regmap = dev_get_regmap(dev->parent, NULL); if (!priv->regmap) return dev_err_probe(dev, -ENODEV, "Failed to get parent regmap\n"); device_for_each_child_node(dev, child) { struct mt6370_led *led = priv->leds + i; led->priv = priv; ret = mt6370_init_flash_properties(dev, led, child); if (ret) { fwnode_handle_put(child); return ret; } ret = mt6370_led_register(dev, led, child); if (ret) { fwnode_handle_put(child); return ret; } i++; } return 0; } static const struct of_device_id mt6370_led_of_id[] = { { .compatible = "mediatek,mt6370-flashlight" }, {} }; MODULE_DEVICE_TABLE(of, mt6370_led_of_id); static struct platform_driver mt6370_led_driver = { .driver = { .name = "mt6370-flashlight", .of_match_table = mt6370_led_of_id, }, .probe = mt6370_led_probe, }; module_platform_driver(mt6370_led_driver); MODULE_AUTHOR("Alice Chen "); MODULE_AUTHOR("ChiYuan Huang "); MODULE_DESCRIPTION("MT6370 FLASH LED Driver"); MODULE_LICENSE("GPL");