From patchwork Mon Sep 18 16:11:03 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Marek_Beh=C3=BAn?= X-Patchwork-Id: 724320 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88099CD13D2 for ; Mon, 18 Sep 2023 16:39:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230352AbjIRQjb (ORCPT ); Mon, 18 Sep 2023 12:39:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40752 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229907AbjIRQjR (ORCPT ); Mon, 18 Sep 2023 12:39:17 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C9A106A60 for ; Mon, 18 Sep 2023 09:11:37 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EF121C116A4; Mon, 18 Sep 2023 16:11:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1695053471; bh=4AhIJuf9x1v9Ii0Sximf2Pwsb3GEAdwoJNPsJUDFblQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DGplOnNoiRbZtBzAGrH1PZd7BbHj/VUvyj6giR+LJ+euaXZCY1SE3fId3r9pJQukO mkzSZGh/44GmzNRUGGRUUc97whop+FGbdjkDmaTkpUgke+9TbxS33JeGU+mulkcW7h 86MFzI3f4o4ShrjSWWtw/XkMwW56oEpGWsHXOBcxIHIj2Gnn4mLiTmbns3LyBG5J6Z Vk+w6M3+sNzYfn4tCrugnqjmYZOqPbHigGdu8nMihbSbLzyJp2oCORAvLV/sHun1Gq N9W9zG//mpb2p7SSMpN2M6AdDBZAPNkk3os/zXdQOiyZQi9D73VWCBBly+A9xEWxiR 8E40GgLaiMWhw== From: =?utf-8?q?Marek_Beh=C3=BAn?= To: Lee Jones , linux-leds@vger.kernel.org Cc: =?utf-8?q?Marek_Beh=C3=BAn?= Subject: [PATCH v4 3/4] leds: turris-omnia: support HW controlled mode via private trigger Date: Mon, 18 Sep 2023 18:11:03 +0200 Message-ID: <20230918161104.20860-4-kabel@kernel.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230918161104.20860-1-kabel@kernel.org> References: <20230918161104.20860-1-kabel@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org Add support for enabling MCU controlled mode of the Turris Omnia LEDs via a LED private trigger called "omnia-mcu". Recall that private LED triggers will only be listed in the sysfs trigger file for LEDs that support them (currently there is no user of this mechanism). When in MCU controlled mode, the user can still set LED color, but the blinking is done by MCU, which does different things for different 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 the corresponding port of the LAN switch - PCIe LEDs are blinked according to the logical OR of the MiniPCIe port LED pins In the future I want to make the netdev trigger to transparently offload the blinking to the HW if user sets compatible settings for the netdev trigger (for LEDs associated with network devices). There was some work on this already, and hopefully we will be able to complete it sometime, but for now there are still multiple blockers for this, and even if there weren't, we still would not be able to configure HW controlled mode for the LEDs associated with MiniPCIe ports. In the meantime let's support HW controlled mode via the private LED trigger mechanism. If, in the future, we manage to complete the netdev trigger offloading, we can still keep this private trigger for backwards compatibility, 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 | 98 +++++++++++++++++++++++++++++--- 2 files changed, 91 insertions(+), 8 deletions(-) diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index b92208eccdea..6292fddcc55c 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -187,6 +187,7 @@ 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 diff --git a/drivers/leds/leds-turris-omnia.c b/drivers/leds/leds-turris-omnia.c index ec5c47d39e85..bdccce0ec39c 100644 --- a/drivers/leds/leds-turris-omnia.c +++ b/drivers/leds/leds-turris-omnia.c @@ -31,7 +31,7 @@ struct omnia_led { struct led_classdev_mc mc_cdev; struct mc_subled subled_info[OMNIA_LED_NUM_CHANNELS]; u8 cached_channels[OMNIA_LED_NUM_CHANNELS]; - bool on; + bool on, hwtrig; int reg; }; @@ -121,12 +121,14 @@ static int omnia_led_brightness_set_blocking(struct led_classdev *cdev, /* * Only recalculate RGB brightnesses from intensities if brightness is - * non-zero. Otherwise we won't be using them and we can save ourselves - * some software divisions (Omnia's CPU does not implement the division - * instruction). + * non-zero (if it is zero and the LED is in HW blinking mode, we use + * max_brightness as brightness). Otherwise we won't be using them and + * we can save ourselves some software divisions (Omnia's CPU does not + * implement the division instruction). */ - if (brightness) { - led_mc_calc_color_components(mc_cdev, brightness); + if (brightness || led->hwtrig) { + led_mc_calc_color_components(mc_cdev, brightness ?: + cdev->max_brightness); /* * Send color command only if brightness is non-zero and the RGB @@ -136,8 +138,11 @@ static int omnia_led_brightness_set_blocking(struct led_classdev *cdev, err = omnia_led_send_color_cmd(leds->client, led); } - /* Send on/off state change only if (bool)brightness changed */ - if (!err && !brightness != !led->on) { + /* + * Send on/off state change only if (bool)brightness changed and the LED + * is not being blinked by HW. + */ + if (!err && !led->hwtrig && !brightness != !led->on) { u8 state = CMD_LED_STATE_LED(led->reg); if (brightness) @@ -153,6 +158,71 @@ static int omnia_led_brightness_set_blocking(struct led_classdev *cdev, return err; } +static struct led_hw_trigger_type omnia_hw_trigger_type; + +static int omnia_hwtrig_activate(struct led_classdev *cdev) +{ + struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev); + struct omnia_leds *leds = dev_get_drvdata(cdev->dev->parent); + struct omnia_led *led = to_omnia_led(mc_cdev); + int err = 0; + + mutex_lock(&leds->lock); + + if (!led->on) { + /* + * If the LED is off (brightness was set to 0), the last + * configured color was not necessarily sent to the MCU. + * Recompute with max_brightness and send if needed. + */ + led_mc_calc_color_components(mc_cdev, cdev->max_brightness); + + if (omnia_led_channels_changed(led)) + err = omnia_led_send_color_cmd(leds->client, led); + } + + if (!err) { + /* Put the LED into MCU controlled mode */ + err = omnia_cmd_write_u8(leds->client, CMD_LED_MODE, + CMD_LED_MODE_LED(led->reg)); + if (!err) + led->hwtrig = true; + } + + mutex_unlock(&leds->lock); + + return err; +} + +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 err; + + mutex_lock(&leds->lock); + + led->hwtrig = false; + + /* Put the LED into software mode */ + err = omnia_cmd_write_u8(leds->client, CMD_LED_MODE, + CMD_LED_MODE_LED(led->reg) | + CMD_LED_MODE_USER); + + mutex_unlock(&leds->lock); + + if (err < 0) + dev_err(cdev->dev, "Cannot put LED to software mode: %i\n", + err); +} + +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_register(struct i2c_client *client, struct omnia_led *led, struct device_node *np) { @@ -196,6 +266,12 @@ static int omnia_led_register(struct i2c_client *client, struct omnia_led *led, 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; + /* + * Use the omnia-mcu trigger as the default trigger. It may be rewritten + * by LED class from the linux,default-trigger property. + */ + cdev->default_trigger = omnia_hw_trigger.name; /* put the LED into software mode */ ret = omnia_cmd_write_u8(client, CMD_LED_MODE, @@ -309,6 +385,12 @@ static int omnia_leds_probe(struct i2c_client *client) 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);