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-rw-r--r--Documentation/leds/leds-class.rst81
-rw-r--r--drivers/leds/trigger/ledtrig-netdev.c141
-rw-r--r--drivers/net/dsa/qca/qca8k-leds.c181
-rw-r--r--include/linux/leds.h53
4 files changed, 437 insertions, 19 deletions
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 <linux/timer.h>
#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)
{
@@ -32,6 +44,43 @@ qca8k_get_enable_led_reg(int port_num, int led_num, struct qca8k_led_pattern_en
}
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)
{
@@ -165,6 +214,133 @@ qca8k_cled_blink_set(struct led_classdev *ldev,
}
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, &reg_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, &reg_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, &reg_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, &reg_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)
{
struct fwnode_handle *led = NULL, *leds = NULL;
@@ -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);