diff --git a/Documentation/leds/leds-class.rst b/Documentation/leds/leds-class.rst index cd155ead8703..5db620ed27aa 100644 --- a/Documentation/leds/leds-class.rst +++ b/Documentation/leds/leds-class.rst @@ -169,6 +169,87 @@ Setting the brightness to zero with brightness_set() callback function should completely turn off the LED and cancel the previously programmed hardware blinking function, if any. +Hardware driven LEDs +==================== + +Some LEDs can be programmed to be driven by hardware. This is not +limited to blink but also to turn off or on autonomously. +To support this feature, a LED needs to implement various additional +ops and needs to declare specific support for the supported triggers. + +With hw control we refer to the LED driven by hardware. + +LED driver must define the following value to support hw control: + + - hw_control_trigger: + unique trigger name supported by the LED in hw control + mode. + +LED driver must implement the following API to support hw control: + - hw_control_is_supported: + check if the flags passed by the supported trigger can + be parsed and activate hw control on the LED. + + Return 0 if the passed flags mask is supported and + can be set with hw_control_set(). + + If the passed flags mask is not supported -EOPNOTSUPP + must be returned, the LED trigger will use software + fallback in this case. + + Return a negative error in case of any other error like + device not ready or timeouts. + + - hw_control_set: + activate hw control. LED driver will use the provided + flags passed from the supported trigger, parse them to + a set of mode and setup the LED to be driven by hardware + following the requested modes. + + Set LED_OFF via the brightness_set to deactivate hw control. + + Return 0 on success, a negative error number on failing to + apply flags. + + - hw_control_get: + get active modes from a LED already in hw control, parse + them and set in flags the current active flags for the + supported trigger. + + Return 0 on success, a negative error number on failing + parsing the initial mode. + Error from this function is NOT FATAL as the device may + be in a not supported initial state by the attached LED + trigger. + + - hw_control_get_device: + return the device associated with the LED driver in + hw control. A trigger might use this to match the + returned device from this function with a configured + device for the trigger as the source for blinking + events and correctly enable hw control. + (example a netdev trigger configured to blink for a + particular dev match the returned dev from get_device + to set hw control) + + Returns a pointer to a struct device or NULL if nothing + is currently attached. + +LED driver can activate additional modes by default to workaround the +impossibility of supporting each different mode on the supported trigger. +Examples are hardcoding the blink speed to a set interval, enable special +feature like bypassing blink if some requirements are not met. + +A trigger should first check if the hw control API are supported by the LED +driver and check if the trigger is supported to verify if hw control is possible, +use hw_control_is_supported to check if the flags are supported and only at +the end use hw_control_set to activate hw control. + +A trigger can use hw_control_get to check if a LED is already in hw control +and init their flags. + +When the LED is in hw control, no software blink is possible and doing so +will effectively disable hw control. Known Issues ============ diff --git a/drivers/leds/trigger/ledtrig-netdev.c b/drivers/leds/trigger/ledtrig-netdev.c index 305eb543ba84..b0a6f2749552 100644 --- a/drivers/leds/trigger/ledtrig-netdev.c +++ b/drivers/leds/trigger/ledtrig-netdev.c @@ -24,6 +24,8 @@ #include #include "../leds.h" +#define NETDEV_LED_DEFAULT_INTERVAL 50 + /* * Configurable sysfs attributes: * @@ -51,15 +53,7 @@ struct led_netdev_data { unsigned long mode; bool carrier_link_up; -}; - -enum led_trigger_netdev_modes { - TRIGGER_NETDEV_LINK = 0, - TRIGGER_NETDEV_TX, - TRIGGER_NETDEV_RX, - - /* Keep last */ - __TRIGGER_NETDEV_MAX, + bool hw_control; }; static void set_baseline_state(struct led_netdev_data *trigger_data) @@ -67,6 +61,13 @@ static void set_baseline_state(struct led_netdev_data *trigger_data) int current_brightness; struct led_classdev *led_cdev = trigger_data->led_cdev; + /* Already validated, hw control is possible with the requested mode */ + if (trigger_data->hw_control) { + led_cdev->hw_control_set(led_cdev, trigger_data->mode); + + return; + } + current_brightness = led_cdev->brightness; if (current_brightness) led_cdev->blink_brightness = current_brightness; @@ -91,6 +92,75 @@ static void set_baseline_state(struct led_netdev_data *trigger_data) } } +static bool supports_hw_control(struct led_classdev *led_cdev) +{ + if (!led_cdev->hw_control_get || !led_cdev->hw_control_set || + !led_cdev->hw_control_is_supported) + return false; + + return !strcmp(led_cdev->hw_control_trigger, led_cdev->trigger->name); +} + +/* + * Validate the configured netdev is the same as the one associated with + * the LED driver in hw control. + */ +static bool validate_net_dev(struct led_classdev *led_cdev, + struct net_device *net_dev) +{ + struct device *dev = led_cdev->hw_control_get_device(led_cdev); + struct net_device *ndev; + + if (!dev) + return false; + + ndev = to_net_dev(dev); + + return ndev == net_dev; +} + +static bool can_hw_control(struct led_netdev_data *trigger_data) +{ + unsigned long default_interval = msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL); + unsigned int interval = atomic_read(&trigger_data->interval); + struct led_classdev *led_cdev = trigger_data->led_cdev; + int ret; + + if (!supports_hw_control(led_cdev)) + return false; + + /* + * Interval must be set to the default + * value. Any different value is rejected if in hw + * control. + */ + if (interval != default_interval) + return false; + + /* + * net_dev must be set with hw control, otherwise no + * blinking can be happening and there is nothing to + * offloaded. Additionally, for hw control to be + * valid, the configured netdev must be the same as + * netdev associated to the LED. + */ + if (!validate_net_dev(led_cdev, trigger_data->net_dev)) + return false; + + /* Check if the requested mode is supported */ + ret = led_cdev->hw_control_is_supported(led_cdev, trigger_data->mode); + /* Fall back to software blinking if not supported */ + if (ret == -EOPNOTSUPP) + return false; + if (ret) { + dev_warn(led_cdev->dev, + "Current mode check failed with error %d\n", ret); + return false; + } + + return true; +} + static ssize_t device_name_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -104,15 +174,9 @@ static ssize_t device_name_show(struct device *dev, return len; } -static ssize_t device_name_store(struct device *dev, - struct device_attribute *attr, const char *buf, - size_t size) +static int set_device_name(struct led_netdev_data *trigger_data, + const char *name, size_t size) { - struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev); - - if (size >= IFNAMSIZ) - return -EINVAL; - cancel_delayed_work_sync(&trigger_data->work); mutex_lock(&trigger_data->lock); @@ -122,7 +186,7 @@ static ssize_t device_name_store(struct device *dev, trigger_data->net_dev = NULL; } - memcpy(trigger_data->device_name, buf, size); + memcpy(trigger_data->device_name, name, size); trigger_data->device_name[size] = 0; if (size > 0 && trigger_data->device_name[size - 1] == '\n') trigger_data->device_name[size - 1] = 0; @@ -140,6 +204,23 @@ static ssize_t device_name_store(struct device *dev, set_baseline_state(trigger_data); mutex_unlock(&trigger_data->lock); + return 0; +} + +static ssize_t device_name_store(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t size) +{ + struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev); + int ret; + + if (size >= IFNAMSIZ) + return -EINVAL; + + ret = set_device_name(trigger_data, buf, size); + + if (ret < 0) + return ret; return size; } @@ -193,6 +274,8 @@ static ssize_t netdev_led_attr_store(struct device *dev, const char *buf, else clear_bit(bit, &trigger_data->mode); + trigger_data->hw_control = can_hw_control(trigger_data); + set_baseline_state(trigger_data); return size; @@ -232,6 +315,9 @@ static ssize_t interval_store(struct device *dev, unsigned long value; int ret; + if (trigger_data->hw_control) + return -EINVAL; + ret = kstrtoul(buf, 0, &value); if (ret) return ret; @@ -359,6 +445,8 @@ static void netdev_trig_work(struct work_struct *work) static int netdev_trig_activate(struct led_classdev *led_cdev) { struct led_netdev_data *trigger_data; + unsigned long mode; + struct device *dev; int rc; trigger_data = kzalloc(sizeof(struct led_netdev_data), GFP_KERNEL); @@ -377,9 +465,24 @@ static int netdev_trig_activate(struct led_classdev *led_cdev) trigger_data->device_name[0] = 0; trigger_data->mode = 0; - atomic_set(&trigger_data->interval, msecs_to_jiffies(50)); + atomic_set(&trigger_data->interval, msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL)); trigger_data->last_activity = 0; + /* Check if hw control is active by default on the LED. + * Init already enabled mode in hw control. + */ + if (supports_hw_control(led_cdev) && + !led_cdev->hw_control_get(led_cdev, &mode)) { + dev = led_cdev->hw_control_get_device(led_cdev); + if (dev) { + const char *name = dev_name(dev); + + set_device_name(trigger_data, name, strlen(name)); + trigger_data->hw_control = true; + trigger_data->mode = mode; + } + } + led_set_trigger_data(led_cdev, trigger_data); rc = register_netdevice_notifier(&trigger_data->notifier); diff --git a/drivers/net/dsa/qca/qca8k-leds.c b/drivers/net/dsa/qca/qca8k-leds.c index b883692b7d86..6f02029b454b 100644 --- a/drivers/net/dsa/qca/qca8k-leds.c +++ b/drivers/net/dsa/qca/qca8k-leds.c @@ -5,6 +5,18 @@ #include "qca8k.h" #include "qca8k_leds.h" +static u32 qca8k_phy_to_port(int phy) +{ + /* Internal PHY 0 has port at index 1. + * Internal PHY 1 has port at index 2. + * Internal PHY 2 has port at index 3. + * Internal PHY 3 has port at index 4. + * Internal PHY 4 has port at index 5. + */ + + return phy + 1; +} + static int qca8k_get_enable_led_reg(int port_num, int led_num, struct qca8k_led_pattern_en *reg_info) { @@ -31,6 +43,43 @@ qca8k_get_enable_led_reg(int port_num, int led_num, struct qca8k_led_pattern_en return 0; } +static int +qca8k_get_control_led_reg(int port_num, int led_num, struct qca8k_led_pattern_en *reg_info) +{ + reg_info->reg = QCA8K_LED_CTRL_REG(led_num); + + /* 6 total control rule: + * 3 control rules for phy0-3 that applies to all their leds + * 3 control rules for phy4 + */ + if (port_num == 4) + reg_info->shift = QCA8K_LED_PHY4_CONTROL_RULE_SHIFT; + else + reg_info->shift = QCA8K_LED_PHY0123_CONTROL_RULE_SHIFT; + + return 0; +} + +static int +qca8k_parse_netdev(unsigned long rules, u32 *offload_trigger) +{ + /* Parsing specific to netdev trigger */ + if (test_bit(TRIGGER_NETDEV_TX, &rules)) + *offload_trigger |= QCA8K_LED_TX_BLINK_MASK; + if (test_bit(TRIGGER_NETDEV_RX, &rules)) + *offload_trigger |= QCA8K_LED_RX_BLINK_MASK; + + if (rules && !*offload_trigger) + return -EOPNOTSUPP; + + /* Enable some default rule by default to the requested mode: + * - Blink at 4Hz by default + */ + *offload_trigger |= QCA8K_LED_BLINK_4HZ; + + return 0; +} + static int qca8k_led_brightness_set(struct qca8k_led *led, enum led_brightness brightness) @@ -164,6 +213,133 @@ qca8k_cled_blink_set(struct led_classdev *ldev, return 0; } +static int +qca8k_cled_trigger_offload(struct led_classdev *ldev, bool enable) +{ + struct qca8k_led *led = container_of(ldev, struct qca8k_led, cdev); + + struct qca8k_led_pattern_en reg_info; + struct qca8k_priv *priv = led->priv; + u32 mask, val = QCA8K_LED_ALWAYS_OFF; + + qca8k_get_enable_led_reg(led->port_num, led->led_num, ®_info); + + if (enable) + val = QCA8K_LED_RULE_CONTROLLED; + + if (led->port_num == 0 || led->port_num == 4) { + mask = QCA8K_LED_PATTERN_EN_MASK; + val <<= QCA8K_LED_PATTERN_EN_SHIFT; + } else { + mask = QCA8K_LED_PHY123_PATTERN_EN_MASK; + } + + return regmap_update_bits(priv->regmap, reg_info.reg, mask << reg_info.shift, + val << reg_info.shift); +} + +static bool +qca8k_cled_hw_control_status(struct led_classdev *ldev) +{ + struct qca8k_led *led = container_of(ldev, struct qca8k_led, cdev); + + struct qca8k_led_pattern_en reg_info; + struct qca8k_priv *priv = led->priv; + u32 val; + + qca8k_get_enable_led_reg(led->port_num, led->led_num, ®_info); + + regmap_read(priv->regmap, reg_info.reg, &val); + + val >>= reg_info.shift; + + if (led->port_num == 0 || led->port_num == 4) { + val &= QCA8K_LED_PATTERN_EN_MASK; + val >>= QCA8K_LED_PATTERN_EN_SHIFT; + } else { + val &= QCA8K_LED_PHY123_PATTERN_EN_MASK; + } + + return val == QCA8K_LED_RULE_CONTROLLED; +} + +static int +qca8k_cled_hw_control_is_supported(struct led_classdev *ldev, unsigned long rules) +{ + u32 offload_trigger = 0; + + return qca8k_parse_netdev(rules, &offload_trigger); +} + +static int +qca8k_cled_hw_control_set(struct led_classdev *ldev, unsigned long rules) +{ + struct qca8k_led *led = container_of(ldev, struct qca8k_led, cdev); + struct qca8k_led_pattern_en reg_info; + struct qca8k_priv *priv = led->priv; + u32 offload_trigger = 0; + int ret; + + ret = qca8k_parse_netdev(rules, &offload_trigger); + if (ret) + return ret; + + ret = qca8k_cled_trigger_offload(ldev, true); + if (ret) + return ret; + + qca8k_get_control_led_reg(led->port_num, led->led_num, ®_info); + + return regmap_update_bits(priv->regmap, reg_info.reg, + QCA8K_LED_RULE_MASK << reg_info.shift, + offload_trigger << reg_info.shift); +} + +static int +qca8k_cled_hw_control_get(struct led_classdev *ldev, unsigned long *rules) +{ + struct qca8k_led *led = container_of(ldev, struct qca8k_led, cdev); + struct qca8k_led_pattern_en reg_info; + struct qca8k_priv *priv = led->priv; + u32 val; + int ret; + + /* With hw control not active return err */ + if (!qca8k_cled_hw_control_status(ldev)) + return -EINVAL; + + qca8k_get_control_led_reg(led->port_num, led->led_num, ®_info); + + ret = regmap_read(priv->regmap, reg_info.reg, &val); + if (ret) + return ret; + + val >>= reg_info.shift; + val &= QCA8K_LED_RULE_MASK; + + /* Parsing specific to netdev trigger */ + if (val & QCA8K_LED_TX_BLINK_MASK) + set_bit(TRIGGER_NETDEV_TX, rules); + if (val & QCA8K_LED_RX_BLINK_MASK) + set_bit(TRIGGER_NETDEV_RX, rules); + + return 0; +} + +static struct device *qca8k_cled_hw_control_get_device(struct led_classdev *ldev) +{ + struct qca8k_led *led = container_of(ldev, struct qca8k_led, cdev); + struct qca8k_priv *priv = led->priv; + struct dsa_port *dp; + + dp = dsa_to_port(priv->ds, qca8k_phy_to_port(led->port_num)); + if (!dp) + return NULL; + if (dp->slave) + return &dp->slave->dev; + return NULL; +} + static int qca8k_parse_port_leds(struct qca8k_priv *priv, struct fwnode_handle *port, int port_num) { @@ -224,6 +400,11 @@ qca8k_parse_port_leds(struct qca8k_priv *priv, struct fwnode_handle *port, int p port_led->cdev.max_brightness = 1; port_led->cdev.brightness_set_blocking = qca8k_cled_brightness_set_blocking; port_led->cdev.blink_set = qca8k_cled_blink_set; + port_led->cdev.hw_control_is_supported = qca8k_cled_hw_control_is_supported; + port_led->cdev.hw_control_set = qca8k_cled_hw_control_set; + port_led->cdev.hw_control_get = qca8k_cled_hw_control_get; + port_led->cdev.hw_control_get_device = qca8k_cled_hw_control_get_device; + port_led->cdev.hw_control_trigger = "netdev"; init_data.default_label = ":port"; init_data.fwnode = led; init_data.devname_mandatory = true; diff --git a/include/linux/leds.h b/include/linux/leds.h index c39bbf17a25b..8af62ff431f0 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -183,6 +183,49 @@ struct led_classdev { /* LEDs that have private triggers have this set */ struct led_hw_trigger_type *trigger_type; + + /* Unique trigger name supported by LED set in hw control mode */ + const char *hw_control_trigger; + /* + * Check if the LED driver supports the requested mode provided by the + * defined supported trigger to setup the LED to hw control mode. + * + * Return 0 on success. Return -EOPNOTSUPP when the passed flags are not + * supported and software fallback needs to be used. + * Return a negative error number on any other case for check fail due + * to various reason like device not ready or timeouts. + */ + int (*hw_control_is_supported)(struct led_classdev *led_cdev, + unsigned long flags); + /* + * Activate hardware control, LED driver will use the provided flags + * from the supported trigger and setup the LED to be driven by hardware + * following the requested mode from the trigger flags. + * Deactivate hardware blink control by setting brightness to LED_OFF via + * the brightness_set() callback. + * + * Return 0 on success, a negative error number on flags apply fail. + */ + int (*hw_control_set)(struct led_classdev *led_cdev, + unsigned long flags); + /* + * Get from the LED driver the current mode that the LED is set in hw + * control mode and put them in flags. + * Trigger can use this to get the initial state of a LED already set in + * hardware blink control. + * + * Return 0 on success, a negative error number on failing parsing the + * initial mode. Error from this function is NOT FATAL as the device + * may be in a not supported initial state by the attached LED trigger. + */ + int (*hw_control_get)(struct led_classdev *led_cdev, + unsigned long *flags); + /* + * Get the device this LED blinks in response to. + * e.g. for a PHY LED, it is the network device. If the LED is + * not yet associated to a device, return NULL. + */ + struct device *(*hw_control_get_device)(struct led_classdev *led_cdev); #endif #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED @@ -509,6 +552,16 @@ static inline void *led_get_trigger_data(struct led_classdev *led_cdev) #endif /* CONFIG_LEDS_TRIGGERS */ +/* Trigger specific enum */ +enum led_trigger_netdev_modes { + TRIGGER_NETDEV_LINK = 0, + TRIGGER_NETDEV_TX, + TRIGGER_NETDEV_RX, + + /* Keep last */ + __TRIGGER_NETDEV_MAX, +}; + /* Trigger specific functions */ #ifdef CONFIG_LEDS_TRIGGER_DISK void ledtrig_disk_activity(bool write);