From 80e643510cb14f116f687e992210c0008a09d869 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marek=20Beh=C3=BAn?= Date: Mon, 4 Jul 2022 12:59:53 +0200 Subject: [PATCH] leds: turris-omnia: support HW controlled mode via private trigger MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add support for enabling MCU controlled mode of the Turris Omnia LEDs via a LED private trigger called "omnia-mcu". When in MCU controlled mode, the user can still set LED color, but the blinking is done by MCU, which does different things for various LEDs: - WAN LED is blinked according to the LED[0] pin of the WAN PHY - LAN LEDs are blinked according to the LED[0] output of corresponding port of the LAN switch - PCIe LEDs are blinked according to the logical OR of the MiniPCIe port LED pins For a long time I wanted to actually do this differently: I wanted to make the netdev trigger to transparently offload the blinking to the HW if user set compatible settings for the netdev trigger. There was some work on this, and hopefully we will be able to complete it sometime, but since there are various complications, it will probably not be soon. In the meantime let's support HW controlled mode via this private LED trigger. If, in the future, we manage to complete the netdev trigger offloading, we can still keep this private trigger for backwards compatiblity, if needed. We also set "omnia-mcu" to cdev->default_trigger, so that the MCU keeps control until the user first wants to take over it. If a different default trigger is specified in device-tree via the `linux,default-trigger` property, LED class will overwrite cdev->default_trigger, and so the DT property will be respected. Signed-off-by: Marek Behún --- drivers/leds/Kconfig | 1 + drivers/leds/leds-turris-omnia.c | 41 ++++++++++++++++++++++++++++++++ 2 files changed, 42 insertions(+) --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -164,6 +164,7 @@ config LEDS_TURRIS_OMNIA depends on I2C depends on MACH_ARMADA_38X || COMPILE_TEST depends on OF + select LEDS_TRIGGERS help This option enables basic support for the LEDs found on the front side of CZ.NIC's Turris Omnia router. There are 12 RGB LEDs on the --- a/drivers/leds/leds-turris-omnia.c +++ b/drivers/leds/leds-turris-omnia.c @@ -72,6 +72,39 @@ static int omnia_cmd_read_u8(const struc return -EIO; } +static struct led_hw_trigger_type omnia_hw_trigger_type; + +static int omnia_hwtrig_activate(struct led_classdev *cdev) +{ + struct omnia_leds *leds = dev_get_drvdata(cdev->dev->parent); + struct omnia_led *led = to_omnia_led(lcdev_to_mccdev(cdev)); + + /* put the LED into MCU controlled mode */ + return i2c_smbus_write_byte_data(leds->client, CMD_LED_MODE, + CMD_LED_MODE_LED(led->reg)); +} + +static void omnia_hwtrig_deactivate(struct led_classdev *cdev) +{ + struct omnia_leds *leds = dev_get_drvdata(cdev->dev->parent); + struct omnia_led *led = to_omnia_led(lcdev_to_mccdev(cdev)); + int ret; + + /* put the LED into software mode */ + ret = i2c_smbus_write_byte_data(leds->client, CMD_LED_MODE, + CMD_LED_MODE_LED(led->reg) | + CMD_LED_MODE_USER); + if (ret < 0) + dev_err(cdev->dev, "Cannot put to software mode: %i\n", ret); +} + +static struct led_trigger omnia_hw_trigger = { + .name = "omnia-mcu", + .activate = omnia_hwtrig_activate, + .deactivate = omnia_hwtrig_deactivate, + .trigger_type = &omnia_hw_trigger_type, +}; + static int omnia_led_brightness_set_blocking(struct led_classdev *cdev, enum led_brightness brightness) { @@ -143,6 +176,8 @@ static int omnia_led_register(struct i2c cdev = &led->mc_cdev.led_cdev; cdev->max_brightness = 255; cdev->brightness_set_blocking = omnia_led_brightness_set_blocking; + cdev->trigger_type = &omnia_hw_trigger_type; + cdev->default_trigger = omnia_hw_trigger.name; /* put the LED into software mode */ ret = omnia_cmd_write_u8(client, CMD_LED_MODE, @@ -249,6 +284,12 @@ static int omnia_leds_probe(struct i2c_c mutex_init(&leds->lock); + ret = devm_led_trigger_register(dev, &omnia_hw_trigger); + if (ret < 0) { + dev_err(dev, "Cannot register private LED trigger: %d\n", ret); + return ret; + } + led = &leds->leds[0]; for_each_available_child_of_node(np, child) { ret = omnia_led_register(client, led, child);