From patchwork Mon Mar 24 13:59:20 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Sergio_P=C3=A9rez?= X-Patchwork-Id: 14027425 Received: from p00-icloudmta-asmtp-us-central-1k-100-percent-8.p00-icloudmta-asmtp-vip.icloud-mail-production.svc.kube.us-central-1k.k8s.cloud.apple.com (p-east1-cluster6-host2-snip4-4.eps.apple.com [57.103.90.145]) (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 8480C25D55A for ; Mon, 24 Mar 2025 14:03:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=57.103.90.145 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742825018; cv=none; b=C24C3Ph/4Sm1RWruOlfNp4rzA2LSevP1TPmYVhc8N6dhtMTlavLInJD5BtuGSKW48vpZJXt/0Ht9hdXxZ92UB04vIYLm9ozYY53J3iWpL142zo7fCcwp8YFFrpMqp+CrsQCbnAWZhNRWeWv4gk2vXpE9ax5scA9X8IGv0OynN0M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742825018; c=relaxed/simple; bh=6Y2CsVi71JRPHLZBHtUCL5LXq4SNhxmS4nTeOSN7U9M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dBdf89eZrt7Alk7u/0wgbj7vQRQmi8ilATuRu4Vd1WFZp+S2WHBJcGifj7848YKzqxJesoahN8WC9EMbQkp5iRBCGNFX6yj6ZCbfjQrqKcFto95/H0k/NNNc8rmv0/VJ3IDwNUZT1ALpxMxxMqEmuFgXST+Cb1FPhMUVOgUGWGo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pereznus.es; spf=pass smtp.mailfrom=pereznus.es; dkim=pass (2048-bit key) header.d=pereznus.es header.i=@pereznus.es header.b=MWygime5; arc=none smtp.client-ip=57.103.90.145 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pereznus.es Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pereznus.es Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pereznus.es header.i=@pereznus.es header.b="MWygime5" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pereznus.es; s=sig1; bh=L/3jVTIh7MFp37vxu36ccNLDUYtIM80/gETCDI1so+I=; h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme; b=MWygime5IeOdEyuTClBEQPZXvDJvEMpfxeYwyvOKWeW/FA496syVWjO2VVn0KiazG blVIBrp/diNdC9H91YUh6XbqOWi20T5jGZRX5iQ5Vl3dZ4dGrBmFw0eSAW1AklkN3R pX4TZ9vIrqxEi8ZMim8PR/kEAoQ01LgvSvVKbWFKbvR8+nR/qS21E+x/xE75teOzWn nRqHXPl95hGa79MRkVWFuHsaMj4n6OuoVTYJ3uXvbPGpka5mjbcjKvCVSkCxIrz5/S ssybsycMTKBN52FmFsAtMqMelR8n6/i/Mt82xLY+ide0MhmAzpMwzTCr50CT0Ai/JP B2wNBdRhc3D5g== Received: from localhost.localdomain (ci-asmtp-me-k8s.p00.prod.me.com [17.57.156.36]) by p00-icloudmta-asmtp-us-central-1k-100-percent-8.p00-icloudmta-asmtp-vip.icloud-mail-production.svc.kube.us-central-1k.k8s.cloud.apple.com (Postfix) with ESMTPSA id 9423A180121B; Mon, 24 Mar 2025 14:03:32 +0000 (UTC) From: Sergio Perez To: Tomasz Duszynski , Jonathan Cameron , Lars-Peter Clausen , Rob Herring , Krzysztof Kozlowski , Conor Dooley , linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Sergio Perez Subject: [PATCH v6 2/2] iio: light: bh1750: Add hardware reset support via GPIO Date: Mon, 24 Mar 2025 14:59:20 +0100 Message-ID: <20250324135920.6802-2-sergio@pereznus.es> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250324135920.6802-1-sergio@pereznus.es> References: <20250324135920.6802-1-sergio@pereznus.es> Precedence: bulk X-Mailing-List: linux-iio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-ORIG-GUID: lpdnBlp3BhFVnQgTLKEq9h7RfPq57Phv X-Proofpoint-GUID: lpdnBlp3BhFVnQgTLKEq9h7RfPq57Phv X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1093,Hydra:6.0.680,FMLib:17.12.68.34 definitions=2025-03-24_04,2025-03-21_01,2024-11-22_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 adultscore=0 bulkscore=0 malwarescore=0 clxscore=1030 mlxscore=0 suspectscore=0 spamscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2308100000 definitions=main-2503240102 Some BH1750 sensors require a hardware reset before they can be detected on the I2C bus. This implementation adds support for an optional reset GPIO that can be specified in the device tree. The reset sequence pulls the GPIO low and then high before initializing the sensor, which enables proper detection with tools like i2cdetect. This is particularly important for sensors that power on in an undefined state. Signed-off-by: Sergio Perez --- Revision history: v5 => v6: - No changes v4 => v5: - Logic change to be coherent with dt-binding as mentioned by Krzysztof Kozlowski - Adjust indentation as commented by Krzysztof Kozlowski v3 => v4: - No changes v2 => v3: - Split in two patches: dtbinding and code - Ensure list on mantainers following instructions by Krzysztof Kozlowski - Fix check tests as explainned by Krzysztof Kozlowski v1 => v2: - Fixes some whitespaces and end lines - Remove unnecessary include - Use of fsleep rather than usleep_range as suggested by Jonathan Cameron - Use of dev_dbg to reduce innecessary output as suggested by Jonathan Cameron - Delete an extra function implementing the functionality inline as suggested by Jonathan Cameron --- drivers/iio/light/bh1750.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/drivers/iio/light/bh1750.c b/drivers/iio/light/bh1750.c index 4b869fa9e5b1..764f88826fcb 100644 --- a/drivers/iio/light/bh1750.c +++ b/drivers/iio/light/bh1750.c @@ -22,12 +22,16 @@ #include #include #include +#include #define BH1750_POWER_DOWN 0x00 #define BH1750_ONE_TIME_H_RES_MODE 0x20 /* auto-mode for BH1721 */ #define BH1750_CHANGE_INT_TIME_H_BIT 0x40 #define BH1750_CHANGE_INT_TIME_L_BIT 0x60 +/* Define the reset delay time in microseconds */ +#define BH1750_RESET_DELAY_US 10000 /* 10ms */ + enum { BH1710, BH1721, @@ -40,6 +44,7 @@ struct bh1750_data { struct mutex lock; const struct bh1750_chip_info *chip_info; u16 mtreg; + struct gpio_desc *reset_gpio; }; struct bh1750_chip_info { @@ -248,6 +253,25 @@ static int bh1750_probe(struct i2c_client *client) data->client = client; data->chip_info = &bh1750_chip_info_tbl[id->driver_data]; + /* Get reset GPIO from device tree */ + data->reset_gpio = devm_gpiod_get_optional(&client->dev, + "reset", GPIOD_OUT_HIGH); + + if (IS_ERR(data->reset_gpio)) + return dev_err_probe(&client->dev, PTR_ERR(data->reset_gpio), + "Failed to get reset GPIO\n"); + + /* Perform hardware reset if GPIO is provided */ + if (data->reset_gpio) { + /* Perform reset sequence: low-high */ + gpiod_set_value_cansleep(data->reset_gpio, 1); + fsleep(BH1750_RESET_DELAY_US); + gpiod_set_value_cansleep(data->reset_gpio, 0); + fsleep(BH1750_RESET_DELAY_US); + + dev_dbg(&client->dev, "BH1750 reset completed via GPIO\n"); + } + usec = data->chip_info->mtreg_to_usec * data->chip_info->mtreg_default; ret = bh1750_change_int_time(data, usec); if (ret < 0)