From patchwork Fri Nov 8 13:28:40 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: 842230 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 9EFDD1EE006; Fri, 8 Nov 2024 13:29:22 +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=1731072562; cv=none; b=LCJEvyB+ozleGcCBJnxLblacLuLg3jPk7GX7wvfnCLYsrjT4TCpI+L1Wkm1hEuX6q4etBZ5s4D0g8BmViYBFJ1Tyu+oIfwd8G9nWteCbbQTbJ2qHz5dgS0Vb3kfxz4syMN+EBLXRzalWy2NSOfN4MajJuHpPqMMH0b4VK5LltAI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731072562; c=relaxed/simple; bh=2mCfw6DyCE9G4G1QDXR052pAiuSPWSjGKmy4YcCQVhM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=sKAvm52QLCxFoNc1ai0e0WOtHdntfY9+FD2fcqz/C10pZWRo03TvWjeBZi47Q6XjHLPA91GEWRr1WLw+TvIHiu4HaF7/Q1tBzGqO388/k8c88d6SDIL/xvrGJX7YjwjleQLOx9zv7WBXTkq9XkNVijuypuWlhY9nqbJoVUkmn68= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=s2LaFnsY; 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="s2LaFnsY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E6FD7C4CED3; Fri, 8 Nov 2024 13:29:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1731072562; bh=2mCfw6DyCE9G4G1QDXR052pAiuSPWSjGKmy4YcCQVhM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=s2LaFnsYVTJcX+S0mu6xfmiscCGEX6OR7am7zbqPt64CjvYDZH009GZQarH+8DnWw dNI6ZD+DLt82MmSRCmoTe4gURXPPt3B6WJkT/CAek9GxYhW3IZN53sMAcyZIp/9J6c Sz69PXOld3wCF2V8SFYkdtZgWqbMVQ+dKuzc9i5/hqi2MDrC51urN/R6VsoZ/J3YHr 0IHe8XFCo+ezsk9pH6tClC7s39GlV8zeGJebdR5XHOCkHEn5+xed+wGNNmlYFF2G0u jSPD/IT2tVxqmqCYveLBc2/sv+Ts4O0tFjtnEp6EJndO/SyMJuWm3Gc+G93DX6FSQ8 ws1rZNveD3StA== 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 v6 07/12] leds: turris-omnia: Notify sysfs on MCU global LEDs brightness change Date: Fri, 8 Nov 2024 14:28:40 +0100 Message-ID: <20241108132845.31005-8-kabel@kernel.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20241108132845.31005-1-kabel@kernel.org> References: <20241108132845.31005-1-kabel@kernel.org> Precedence: bulk X-Mailing-List: linux-leds@vger.kernel.org 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 | 62 ++++++++++++++++++++++++++++++++ 2 files changed, 63 insertions(+) diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index fcbe93b61e49..9ab6b56898c6 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -218,6 +218,7 @@ config LEDS_TURRIS_OMNIA depends on MACH_ARMADA_38X || COMPILE_TEST depends on OF depends on TURRIS_OMNIA_MCU + depends on TURRIS_OMNIA_MCU_GPIO select LEDS_TRIGGERS help This option enables basic support for the LEDs found on the front diff --git a/drivers/leds/leds-turris-omnia.c b/drivers/leds/leds-turris-omnia.c index 7d2ed0c6500a..b2c37dd2e1cc 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 +376,59 @@ 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)) { + /* + * 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 void omnia_brightness_knode_put(void *data) +{ + struct omnia_leds *leds = data; + + if (leds->brightness_knode) + sysfs_put(leds->brightness_knode); +} + +static int omnia_request_brightness_irq(struct omnia_leds *leds) +{ + struct device *dev = &leds->client->dev; + int ret; + + if (!leds->client->irq) { + dev_info(dev, + "Brightness change interrupt supported by MCU firmware but not described in device-tree\n"); + + return 0; + } + + /* + * Registering the brightness_knode destructor before requesting the IRQ ensures that on + * removal the brightness_knode sysfs node is put only after the IRQ is freed. + * This is needed because the interrupt handler uses the knode. + */ + ret = devm_add_action(dev, omnia_brightness_knode_put, leds); + if (ret < 0) + return ret; + + return devm_request_threaded_irq(dev, leds->client->irq, NULL, + omnia_brightness_changed_threaded_fn, IRQF_ONESHOT, + "leds-turris-omnia", leds); +} + static int omnia_mcu_get_features(const struct i2c_client *mcu_client) { u16 reply; @@ -459,6 +515,12 @@ 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 = omnia_request_brightness_irq(leds); + if (ret < 0) + return dev_err_probe(dev, ret, "Cannot request brightness IRQ\n"); + } + mutex_init(&leds->lock); ret = devm_led_trigger_register(dev, &omnia_hw_trigger);