From patchwork Mon Nov 4 14:19:19 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: 13861481 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 E7F7C4502B for ; Mon, 4 Nov 2024 14:20:00 +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=1730730001; cv=none; b=jrarhIaQ32HfihM812Z5U2fOszQGsK9zJHpHQu3NZEb10rm7LBKsJ3o37jyZ6reEL0DIO05eGgGT/lLJBCtIHeBnWrRgEIj+Y0ZbsP12BjXsMAkKbfOY/3q1wVR1UmwLA91vuJww2ODg9cxNvjpDSIAWrSZbHFeBrI1NVPFvgg8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730730001; c=relaxed/simple; bh=SlODgSG/IsQ68Nggxqk0gTPcTViSrI9YmTzyE7UmCnY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=nHNf7ujptzoUhpgz0ILfwxfvAuPHxHhlIRWDuUfUHKQeizzlkSxnHjtvjc501OJtfIOSEuuO1CyqYvqR3jPrnUkNor2RBRp6my7XattPC7kWiA8JvjVZEllsBQrtM306BcI4FtImNXjq/Bpl91ycSjxusjcrnU1IvFqOZ5ZG9Fk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Fw/ZaRQp; 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="Fw/ZaRQp" Received: by smtp.kernel.org (Postfix) id DC049C4AF0C; Mon, 4 Nov 2024 14:20:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 314B6C4CED2; Mon, 4 Nov 2024 14:19:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730730000; bh=SlODgSG/IsQ68Nggxqk0gTPcTViSrI9YmTzyE7UmCnY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Fw/ZaRQp9UW+1qqpdjedwC/MfQuzwUkHLjnMAqPa/GAU7yKAtwB/QjZ902/DT+l5t gYA3duve2L6zILYMA/IkTWOrs/VNklAsUIOkU2DaJn1AfDzh4QsaOA5jTzJbmjeZyL z2p5/hP8WWJ6/qHBJKV5FTe+IpqK1PeGOWn4RKDwiNLdFPI2olnSXShd9LwKvkUBEU iUXy8WU0zkHYBoXh1zjw43qo/P+dCv1qUBUTlf9guKVvQd4LxBTY9nSqEIABEK2Iea Nlsq11EIPh47wgvZBThS7C1z66S8lRvqtIbl/uKzr4VG6o2ByF6OcUBLCxGQ9eke4E DqoayPUMKQO1A== 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 v5 07/12] leds: turris-omnia: Notify sysfs on MCU global LEDs brightness change Date: Mon, 4 Nov 2024 15:19:19 +0100 Message-ID: <20241104141924.18816-8-kabel@kernel.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20241104141924.18816-1-kabel@kernel.org> References: <20241104141924.18816-1-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 | 2 +- drivers/leds/leds-turris-omnia.c | 48 ++++++++++++++++++++++++++++++++ 2 files changed, 49 insertions(+), 1 deletion(-) diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index fcbe93b61e49..148384aacdcc 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -217,7 +217,7 @@ config LEDS_TURRIS_OMNIA depends on I2C 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..168ce362fd14 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 *mcu_client) { u16 reply; @@ -459,6 +486,14 @@ static int omnia_leds_probe(struct i2c_client *client) "Consider upgrading MCU firmware with the omnia-mcutool utility.\n"); } + if (client->irq && (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, "Cannot request brightness IRQ\n"); + } + mutex_init(&leds->lock); ret = devm_led_trigger_register(dev, &omnia_hw_trigger); @@ -481,6 +516,19 @@ 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));