From patchwork Tue Oct 29 13:56:16 2024 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: 13854951 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C1133206E6D for ; Tue, 29 Oct 2024 13:57:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730210220; cv=none; b=PqR72K16Gk+lVC3UkXUrEqw3nyYzszmAvEJT8uCGfKuVm68FXJ2KZlOgyKTRwhanrzbfxNnQyiSfrTPZcf7LdbQIldNk97bkzd/oz44ATH2RsN7rTQ2M5ntyJS+ZG9R/5rrir219tyupYCIT4TcE+6EJ9Eds0UzeBAvHZPGHRsM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730210220; c=relaxed/simple; bh=MSD9y2n/tjvuERbL3dPKRUkIWXA6bylEOX2usY03xaM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Vd/QusRW23EXLTKhqwbUgoJxrfJ89RCENAuLJ87c17j6giyzkwVsuMEFkOr1VTzgPfobyDQElKTPGv3p9Bu181JjW2RlvkJSXSKPkS1OjqBOeHnT6eVvRnToarEXS8jiLiMmMxur+pVlVCBkfMbjTUYYtk4jdmn78YeWxQlrTdU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gDBkUyDl; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gDBkUyDl" Received: by smtp.kernel.org (Postfix) id B71BBC4AF09; Tue, 29 Oct 2024 13:57:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 41382C4CEE3; Tue, 29 Oct 2024 13:56:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730210220; bh=MSD9y2n/tjvuERbL3dPKRUkIWXA6bylEOX2usY03xaM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gDBkUyDlycXFxow+CiF4Wjz3K07iHLBooLXkde89U8WYzNegzwdd5jRdh+guKBTOU xiMy38OJgwUo3PX49mDP6txPLC2amXfBXocEKG858+anUZiEcQY2UqFk7JIopqe6bm erpXsYSg1vpvYo0/NEevMcEkZJTe0nbC8bqi9dZKtBOA32/oBAfq8hXY0sR7LiUhEZ JBa7pFTmyC2CiGKwZcZiXQM2XaD0mdcSW1FLPphYMPhJlcERGE3sDYzUwWAPR5CFid eUB1k+S988bLbClf41CI/MFvd0O4QWrWtARQhN6s3YCQsBoTs/2QWj/zuIOOTcS2w7 7wFYF4iAIJQKA== From: =?utf-8?q?Marek_Beh=C3=BAn?= To: Lee Jones Cc: Pavel Machek , linux-leds@vger.kernel.org, Arnd Bergmann , soc@kernel.org, Gregory CLEMENT , arm@kernel.org, Andy Shevchenko , Hans de Goede , =?utf-8?q?Ilpo_J=C3=A4rvinen?= , Andrew Lunn , Sebastian Hesselbarth , Rob Herring , Krzysztof Kozlowski , Conor Dooley , devicetree@vger.kernel.org, =?utf-8?q?M?= =?utf-8?q?arek_Beh=C3=BAn?= Subject: [PATCH leds v4 07/12] leds: turris-omnia: Notify sysfs on MCU global LEDs brightness change Date: Tue, 29 Oct 2024 14:56:16 +0100 Message-ID: <20241029135621.12546-8-kabel@kernel.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20241029135621.12546-1-kabel@kernel.org> References: <20241029135621.12546-1-kabel@kernel.org> Precedence: bulk X-Mailing-List: soc@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Recall that on Turris Omnia, the LED controller has a global brightness property, which allows the user to make the front LED panel dimmer. There is also a button on the front panel, which by default is configured so that pressing it changes the global brightness to a lower value (unless it is at 0%, in which case pressing the button changes the global brightness to 100%). Newer versions of the MCU firmware support informing the SOC that the brightness was changed by button press event via an interrupt. Now that we have the turris-omnia-mcu driver, which adds support for MCU interrupts, add the ability to inform the userspace (via a sysfs notification) that the global brightness was changed. Signed-off-by: Marek Behún --- drivers/leds/Kconfig | 1 + drivers/leds/leds-turris-omnia.c | 48 ++++++++++++++++++++++++++++++++ 2 files changed, 49 insertions(+) diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index fcbe93b61e49..443aaf948bb8 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -219,6 +219,7 @@ config LEDS_TURRIS_OMNIA depends on OF depends on TURRIS_OMNIA_MCU select LEDS_TRIGGERS + select TURRIS_OMNIA_MCU_GPIO 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 b13b3b269ae9..ac7938f57bfe 100644 --- a/drivers/leds/leds-turris-omnia.c +++ b/drivers/leds/leds-turris-omnia.c @@ -43,12 +43,15 @@ struct omnia_led { * @client: I2C client device * @lock: mutex to protect * @has_gamma_correction: whether the MCU firmware supports gamma correction + * @brightness_knode: kernel node of the "brightness" device sysfs attribute (this is the + * driver specific global brightness, not the LED classdev brightness) * @leds: flexible array of per-LED data */ struct omnia_leds { struct i2c_client *client; struct mutex lock; bool has_gamma_correction; + struct kernfs_node *brightness_knode; struct omnia_led leds[]; }; @@ -373,6 +376,30 @@ static struct attribute *omnia_led_controller_attrs[] = { }; ATTRIBUTE_GROUPS(omnia_led_controller); +static irqreturn_t omnia_brightness_changed_threaded_fn(int irq, void *data) +{ + struct omnia_leds *leds = data; + + if (unlikely(!leds->brightness_knode)) { + /* + * It would be nicer to get this dirent in the driver probe method, before the IRQ + * is requested. But the really_probe() function in drivers/base/dd.c registers + * driver's .dev_groups only after probe is finished, so during driver probe the + * "brightness" sysfs node is not yet present. + * + * Note that sysfs_get_dirent() may sleep. This is okay, because we are in threaded + * context. + */ + leds->brightness_knode = sysfs_get_dirent(leds->client->dev.kobj.sd, "brightness"); + if (!leds->brightness_knode) + return IRQ_NONE; + } + + sysfs_notify_dirent(leds->brightness_knode); + + return IRQ_HANDLED; +} + static int omnia_mcu_get_features(const struct i2c_client *client) { struct i2c_client mcu_client = *client; @@ -436,6 +463,14 @@ static int omnia_leds_probe(struct i2c_client *client) "Consider upgrading MCU firmware with the omnia-mcutool utility.\n"); } + if (ret & OMNIA_FEAT_BRIGHTNESS_INT) { + ret = devm_request_threaded_irq(dev, client->irq, NULL, + omnia_brightness_changed_threaded_fn, IRQF_ONESHOT, + "leds-turris-omnia", leds); + if (ret <= 0) + return dev_err_probe(dev, ret ?: -ENXIO, "Cannot request brightness IRQ\n"); + } + mutex_init(&leds->lock); ret = devm_led_trigger_register(dev, &omnia_hw_trigger); @@ -458,6 +493,19 @@ static int omnia_leds_probe(struct i2c_client *client) static void omnia_leds_remove(struct i2c_client *client) { + struct omnia_leds *leds = i2c_get_clientdata(client); + + /* + * We need to free the brightness IRQ here, before putting away the brightness sysfs node. + * Otherwise devres would free the interrupt only after the sysfs node is removed, and if + * an interrupt occurred between those two events, it would use a removed sysfs node. + */ + devm_free_irq(&client->dev, client->irq, leds); + + /* Now put away the sysfs node we got the first time the interrupt handler was called */ + if (leds->brightness_knode) + sysfs_put(leds->brightness_knode); + /* put all LEDs into default (HW triggered) mode */ omnia_cmd_write_u8(client, OMNIA_CMD_LED_MODE, OMNIA_CMD_LED_MODE_LED(OMNIA_BOARD_LEDS));