From mboxrd@z Thu Jan 1 00:00:00 1970 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 D7A27C7EE2D for ; Sun, 26 Feb 2023 12:52:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229549AbjBZMwm (ORCPT ); Sun, 26 Feb 2023 07:52:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33614 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229605AbjBZMwl (ORCPT ); Sun, 26 Feb 2023 07:52:41 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C885811646; Sun, 26 Feb 2023 04:52:38 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 46415B80B7C; Sun, 26 Feb 2023 12:52:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7975CC433D2; Sun, 26 Feb 2023 12:52:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1677415955; bh=oEQsjh8Gi31+5wH5xx1MJkmxpc3pijYr5zWuKl/aPzs=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=PyHv21EgYDcD0G6sQucjz6ObfE4Z3fXq49xfVkFUumDc7edBeciQdk+hZYvaskZmc yKPJjD0xISbCw8m1i0FJCgPqYKWnJCz6eSaMJxwtkgoAGiFK7KzPgJoj4JHU4957iY 79x9z/CYHVAVqMdJVDZC72SWQX6xzVOGNK//K7DdbAyxLP3P3Qf/eSe77n9ZZLd6OT O+myq6Egyb7L3dT8zL8w3aBI75gJHgg0m24h1NBdZ1kgvUXEGkcf6qvGmtyHt5eBHx L0N/XEoQNYp98FUrRIOFROnUEpbftDTTEckQmchkVq2LXU9ohiH20h5GXj4r69uLpA RZTqZlm9YRTMg== Date: Sun, 26 Feb 2023 13:07:00 +0000 From: Jonathan Cameron To: Marco Felsch Cc: puranjay12@gmail.com, lars@metafoo.de, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, linux-iio@vger.kernel.org, devicetree@vger.kernel.org, kernel@pengutronix.de Subject: Re: [PATCH v4 2/5] iio: temperature: tmp117: improve fallback capabilities Message-ID: <20230226130700.5b0d650f@jic23-huawei> In-Reply-To: <20230220122552.925216-3-m.felsch@pengutronix.de> References: <20230220122552.925216-1-m.felsch@pengutronix.de> <20230220122552.925216-3-m.felsch@pengutronix.de> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.36; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Mon, 20 Feb 2023 13:25:49 +0100 Marco Felsch wrote: > Don't error if the device-id found don't match the device-id for the > TMP117 sensor since other TMPxxx might be compatible to the TMP117. The > fallback mechanism tries to gather the required information from the > of_device_id or from the i2c_client information. > > The commit also prepares the driver for adding new devices more easily > by making use of switch-case at the relevant parts. > > Signed-off-by: Marco Felsch Hi Marco, Thanks for doing this. A small things inline. > --- > v4: > - new patch to implement possible fallback (Jonathan) > > drivers/iio/temperature/tmp117.c | 67 +++++++++++++++++++++----------- > 1 file changed, 44 insertions(+), 23 deletions(-) > > diff --git a/drivers/iio/temperature/tmp117.c b/drivers/iio/temperature/tmp117.c > index f9b8f2b570f6b..4ddb8cf9a29ab 100644 > --- a/drivers/iio/temperature/tmp117.c > +++ b/drivers/iio/temperature/tmp117.c > @@ -16,6 +16,7 @@ > #include > #include > #include > +#include > > #include > > @@ -113,32 +114,60 @@ static const struct iio_info tmp117_info = { > .write_raw = tmp117_write_raw, > }; > > +static const struct of_device_id tmp117_of_match[] = { > + { .compatible = "ti,tmp117", .data = (void *)TMP117_DEVICE_ID }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, tmp117_of_match); > + > +static const struct i2c_device_id tmp117_id[] = { > + { "tmp117", TMP117_DEVICE_ID }, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, tmp117_id); As below. There is an easy way to avoid having to move these. > + > static int tmp117_identify(struct i2c_client *client) > { > + unsigned long match_data; > int dev_id; > > dev_id = i2c_smbus_read_word_swapped(client, TMP117_REG_DEVICE_ID); > if (dev_id < 0) > return dev_id; > - if (dev_id != TMP117_DEVICE_ID) { > - dev_err(&client->dev, "TMP117 not found\n"); > - return -ENODEV; > + > + switch (dev_id) { > + case TMP117_DEVICE_ID: > + return dev_id; > } > - return 0; > + > + dev_info(&client->dev, "Unknown device id (0x%x), use fallback compatible\n", > + dev_id); > + > + match_data = (uintptr_t)device_get_match_data(&client->dev); > + if (match_data) > + return match_data; > + > + match_data = i2c_match_id(tmp117_id, client)->driver_data; Whilst correct, i2c_client_get_device_id() avoids the need to move tmp117_id up to where you have by getting to that table via the driver structure. That will simplify this patch a fair bit. > + if (match_data) > + return match_data; > + > + dev_err(&client->dev, "error: No valid fallback found\n"); This is a little misleading as fallback only applies to the device tree path. Also, not a lot of point in putting error in the text of a dev_err. Perhaps just "Unsupported device". > + > + return -ENODEV; > } > > static int tmp117_probe(struct i2c_client *client) > { > struct tmp117_data *data; > struct iio_dev *indio_dev; > - int ret; > + int dev_id; > > if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA)) > return -EOPNOTSUPP; > > - ret = tmp117_identify(client); > - if (ret < 0) > - return ret; > + dev_id = tmp117_identify(client); > + if (dev_id < 0) > + return dev_id; I'd keep it in ret until you know it's good. Reduces churn and is nicer code in general, though one more line. dev_id = ret; > > indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); > if (!indio_dev) > @@ -148,28 +177,20 @@ static int tmp117_probe(struct i2c_client *client) > data->client = client; > data->calibbias = 0; > > - indio_dev->name = "tmp117"; > indio_dev->modes = INDIO_DIRECT_MODE; > indio_dev->info = &tmp117_info; > > - indio_dev->channels = tmp117_channels; > - indio_dev->num_channels = ARRAY_SIZE(tmp117_channels); > + switch (dev_id) { > + case TMP117_DEVICE_ID: > + indio_dev->channels = tmp117_channels; > + indio_dev->num_channels = ARRAY_SIZE(tmp117_channels); > + indio_dev->name = "tmp117"; > + break; > + } > > return devm_iio_device_register(&client->dev, indio_dev); > } > > -static const struct of_device_id tmp117_of_match[] = { > - { .compatible = "ti,tmp117", }, > - { } > -}; > -MODULE_DEVICE_TABLE(of, tmp117_of_match); > - > -static const struct i2c_device_id tmp117_id[] = { > - { "tmp117", 0 }, > - { } > -}; > -MODULE_DEVICE_TABLE(i2c, tmp117_id); > - > static struct i2c_driver tmp117_driver = { > .driver = { > .name = "tmp117",