From mboxrd@z Thu Jan 1 00:00:00 1970 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 E98FE3815ED; Sun, 17 May 2026 13:34:58 +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=1779024899; cv=none; b=MhO8y3PnhSuSb2DwLNv6I7bHBhmldjY2EKRfGFTbMplf3MhQjF6mgYQgcKyeV/T0seO8o8jlHcRGCWHGHcEfh+2WjYPsbMmAM3PPb6ld3ypcwaNYD/XSuQB96wplv2BtMSqGrw4sIgPr3srcml7E8bEdDvOS4dMuOSRoK8aluwE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779024899; c=relaxed/simple; bh=bKjlUmu59QzY3yUZwYKvRaqn7Hamk+Za8Jpd1+c9Kvg=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=IMMkDl6uI3iNULbVY3lksTlXZxNUKgExe1fUimgzLU7JrQC5H4nnYYcBwTgwc1Nac74WI1gcQ/XGYu6NiIRL4Hn9t7wpWRscdzqwMppY0KMKXW3bN5cXsRBJ+F691IDEp1gWr72SDOjDrofGICGoZ+T4tcsZRPZAH4D2LeJGYwY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=OMOPFh46; 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="OMOPFh46" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE148C2BCB0; Sun, 17 May 2026 13:34:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1779024898; bh=bKjlUmu59QzY3yUZwYKvRaqn7Hamk+Za8Jpd1+c9Kvg=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=OMOPFh466oF/mwIvfESTrv8xBSGuBY2lPBxnGIbKMcj5RHupBsc9XVAHmnD/tYcD3 n4N4oKCdSuwJlBC39TqC3mXmEZdn6HZgEw3A6g1kMW7vaYlxdTKrKN3uWJoo7S5SMF piaQGJTDgpVzi89Saf5UOZcvI9wswTtR8HH5NWhf8CuhUDR/5UySL/T5kJhFc/Qrh/ YmAj0uBlkYONd51WF8iplAMHa3l8ViKWirROSryDeMkIl2fjGUnueAXdVMwK3OKK6w bJ/1yaUTF8pcghLrIe7ZbbNDZR7Af+WKi/wvM+pkpaDHhWX5Okb7zyRj6y7JdJSpsy RZOUTCs8HgXdA== Date: Sun, 17 May 2026 14:34:49 +0100 From: Jonathan Cameron To: Joshua Crofts Cc: David Lechner , Nuno =?UTF-8?B?U8Oh?= , Andy Shevchenko , Rob Herring , Krzysztof Kozlowski , Conor Dooley , linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] iio: light: veml3328: add support for new device Message-ID: <20260517143449.6c30b99f@jic23-huawei> In-Reply-To: <20260516-veml3328-v1-2-1d4b663e2fe3@gmail.com> References: <20260516-veml3328-v1-0-1d4b663e2fe3@gmail.com> <20260516-veml3328-v1-2-1d4b663e2fe3@gmail.com> X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Sat, 16 May 2026 23:50:54 +0200 Joshua Crofts wrote: > Add support for the Vishay VEML3328 RGB/IR light sensor communicating > via I2C (SMBus compatible). > > Also add a new entry for said driver into Kconfig and Makefile. > > Signed-off-by: Joshua Crofts Hi Joshua, Pretty nice for a v1. A few comments inline to add to the other reviews (I may well have duplicated some!) Jonathan > diff --git a/drivers/iio/light/veml3328.c b/drivers/iio/light/veml3328.c > new file mode 100644 > index 000000000000..9eb5429c813d > --- /dev/null > +++ b/drivers/iio/light/veml3328.c > @@ -0,0 +1,405 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Vishay VEML3328 RGBCIR light sensor driver > + * > + * Copyright (c) 2026 Joshua Crofts > + * > + * Datasheet: https://www.vishay.com/docs/84968/veml3328.pdf > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > + > +#define VEML3328_REG_CONF 0x00 > +#define VEML3328_REG_ID 0x0c > +#define VEML3328_REG_DATA_C 0x04 > +#define VEML3328_REG_DATA_R 0x05 > +#define VEML3328_REG_DATA_G 0x06 > +#define VEML3328_REG_DATA_B 0x07 > +#define VEML3328_REG_DATA_IR 0x08 > + > +#define VEML3328_IT_MASK GENMASK(5, 4) > +#define VEML3328_GAIN_MASK GENMASK(11, 10) Name these so it is obvious which register they are in. I guess VEML3328_CONF_IT_MASK etc. > + > +#define VEML3328_ID_VAL 0x28 > + > +#define VEML3328_CONF_SD0 BIT(0) > +#define VEML3328_CONF_SD1 BIT(15) These two don't add anything given always used together. > +#define VEML3328_SHUTDOWN (VEML3328_CONF_SD0 | VEML3328_CONF_SD1) #define VEML3328_SHUTDOWN BIT(0) | BIT(15) is sufficient > + > +struct veml3328_data { > + struct regmap *regmap; > + struct device *dev; The use of the one embedded in regmap got mentioned already in another review. > + struct mutex lock; All locks need a comment saying what data they are protecting (might well be in the device). Mind you - I'm seeing quite a bit of locking around simple regmap calls. Given there are locks in regmap, you may need to call out if there is a particular readout sequence that must not be interrupted. I'm not immediately seeing one and as such you might not need a local lock. > +}; > + > +static const struct regmap_config veml3328_regmap_config = { > + .name = "veml3328", > + .reg_bits = 8, > + .val_bits = 16, > + .max_register = VEML3328_REG_ID, > + .val_format_endian = REGMAP_ENDIAN_LITTLE, > +}; > + > +#define VEML3328_CHAN_SPEC(_color, _addr) { \ > + .type = IIO_INTENSITY, \ > + .modified = 1, \ > + .channel2 = IIO_MOD_LIGHT_##_color, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME) | \ > + BIT(IIO_CHAN_INFO_SCALE), \ > + .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME) | \ > + BIT(IIO_CHAN_INFO_SCALE), \ > + .address = _addr, \ > +} > + > +static const struct iio_chan_spec veml3328_channels[] = { > + VEML3328_CHAN_SPEC(CLEAR, VEML3328_REG_DATA_C), Would be nice to have a an IIO_LUX channel (always an approximation) as that tends to be what userspace wanges. Hmm. I googled a bit. Seems there is a note that has more info. https://www.vishay.com/docs/80010/designingveml3328.pdf Interestingly suggests that green channel is nearer than clear. If you can put the correct scaling in that would be a good thing to support (keep the green as well). > + VEML3328_CHAN_SPEC(RED, VEML3328_REG_DATA_R), > + VEML3328_CHAN_SPEC(GREEN, VEML3328_REG_DATA_G), > + VEML3328_CHAN_SPEC(BLUE, VEML3328_REG_DATA_B), > + VEML3328_CHAN_SPEC(IR, VEML3328_REG_DATA_IR), > +}; > + > +static int veml3328_power_up(struct veml3328_data *data) > +{ > + int ret; > + > + ret = regmap_update_bits(data->regmap, VEML3328_REG_CONF, > + VEML3328_SHUTDOWN, 0); > + if (ret < 0) > + return ret; > + > + fsleep(veml3328_it_times[3][1]); Add a comment on why we need to sleep maximum integration time. > + > + return 0; > +} > + > +static void veml3328_power_down_action(void *data) > +{ > + veml3328_power_down(data); > +} > + > +static int veml3328_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long mask) > +{ > + struct veml3328_data *data = iio_priv(indio_dev); > + struct regmap *regmap = data->regmap; > + unsigned int reg_val; > + int ret; > + int reg; > + > + guard(mutex)(&data->lock); > + > + ret = pm_runtime_resume_and_get(data->dev); > + if (ret < 0) > + return ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + ret = regmap_read(regmap, chan->address, ®_val); > + if (ret < 0) > + goto exit; > + > + *val = reg_val; > + ret = IIO_VAL_INT; > + break; > + > + case IIO_CHAN_INFO_INT_TIME: > + ret = regmap_read(regmap, VEML3328_REG_CONF, ®_val); > + if (ret < 0) > + goto exit; > + > + reg = FIELD_GET(VEML3328_IT_MASK, reg_val); > + if (reg >= ARRAY_SIZE(veml3328_it_times)) { > + ret = -EINVAL; > + goto exit; > + } > + > + *val = veml3328_it_times[reg][0]; > + *val2 = veml3328_it_times[reg][1]; > + ret = IIO_VAL_INT_PLUS_MICRO; > + break; > + > + case IIO_CHAN_INFO_SCALE: > + ret = regmap_read(regmap, VEML3328_REG_CONF, ®_val); > + if (ret < 0) > + goto exit; > + > + reg = FIELD_GET(VEML3328_GAIN_MASK, reg_val); > + if (reg >= ARRAY_SIZE(veml3328_scale_vals)) { > + ret = -EINVAL; > + goto exit; > + } > + > + *val = veml3328_scale_vals[reg][0]; > + *val2 = veml3328_scale_vals[reg][1]; > + ret = IIO_VAL_INT_PLUS_MICRO; > + break; > + > + default: > + ret = -EINVAL; > + } > + > +exit: > + pm_runtime_put_autosuspend(data->dev); See below for comment on how to handle this using stuff that ultimately comes from cleanup.h > + > + return ret; > +} > + > + > +static int veml3328_write_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int val, int val2, long mask) > +{ > + struct veml3328_data *data = iio_priv(indio_dev); > + struct regmap *regmap = data->regmap; > + int ret; > + int i; > + > + guard(mutex)(&data->lock); > + > + ret = pm_runtime_resume_and_get(data->dev); PM_RUNTIME_ACQUIRE_AUTOSUSPEND() will mean you can rely on this being auto suspended on exiting scope. Will allow early returns and get rid of your goto that you noted already. > + if (ret < 0) > + return ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_INT_TIME: > + if (val != 0) { > + ret = -EINVAL; > + goto exit; With above, all these become direct returns. > + } > + > + for (i = 0; i < ARRAY_SIZE(veml3328_it_times); i++) { > + if (veml3328_it_times[i][1] == val2) > + break; > + } > + > + if (i == ARRAY_SIZE(veml3328_it_times)) { > + ret = -EINVAL; > + goto exit; > + } > + > + ret = regmap_update_bits(regmap, VEML3328_REG_CONF, > + VEML3328_IT_MASK, > + FIELD_PREP(VEML3328_IT_MASK, i)); > + break; > + > + case IIO_CHAN_INFO_SCALE: > + for (i = 0; i < ARRAY_SIZE(veml3328_scale_vals); i++) { > + if (val == veml3328_scale_vals[i][0] && > + val2 == veml3328_scale_vals[i][1]) > + break; > + } > + > + if (i == ARRAY_SIZE(veml3328_scale_vals)) { > + ret = -EINVAL; > + goto exit; > + } > + > + ret = regmap_update_bits(regmap, VEML3328_REG_CONF, > + VEML3328_GAIN_MASK, > + FIELD_PREP(VEML3328_GAIN_MASK, i)); > + > + break; > + > + default: > + ret = -EINVAL; > + } > + > +exit: > + pm_runtime_put_autosuspend(data->dev); > + > + return ret; > +} > + > +static int veml3328_write_raw_get_fmt(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + long mask) > +{ > + switch (mask) { > + case IIO_CHAN_INFO_SCALE: > + case IIO_CHAN_INFO_INT_TIME: > + return IIO_VAL_INT_PLUS_MICRO; That's the default - no need for the callback. > + default: > + return -EINVAL; > + } > +} > + > +static const struct iio_info veml3328_info = { > + .read_raw = veml3328_read_raw, > + .write_raw = veml3328_write_raw, > + .read_avail = veml3328_read_avail, > + .write_raw_get_fmt = veml3328_write_raw_get_fmt, > +}; > + > +static int veml3328_probe(struct i2c_client *client) > +{ > + struct device *dev = &client->dev; > + struct veml3328_data *data; > + struct iio_dev *indio_dev; > + unsigned int reg_val; > + int ret; > + > + indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); > + if (!indio_dev) > + return -ENOMEM; > + > + data = iio_priv(indio_dev); > + i2c_set_clientdata(client, indio_dev); > + data->dev = dev; > + > + data->regmap = devm_regmap_init_i2c(client, &veml3328_regmap_config); > + if (IS_ERR(data->regmap)) > + return dev_err_probe(dev, PTR_ERR(data->regmap), > + "Failed to initialize regmap\n"); > + > + ret = devm_mutex_init(dev, &data->lock); > + if (ret) > + return ret; > + > + ret = devm_regulator_get_enable(dev, "vdd"); > + if (ret) > + return dev_err_probe(dev, ret, "Failed to enable regulator\n"); > + > + ret = regmap_read(data->regmap, VEML3328_REG_ID, ®_val); > + if (ret < 0) > + return dev_err_probe(dev, ret, "Failed to read ID register\n"); > + > + if ((reg_val & 0xff) != VEML3328_ID_VAL) > + return dev_err_probe(dev, -ENODEV, "Invalid device ID\n"); This breaks fallback dt compatibles. If some future part is released that backwards compatible with this one, then the dt-binding will reflect that. That future part will typically have a different ID_VAL. We need that case of new binding, older kernel to work so this can't fail probe. It is fine to print a message though to indicate we are seeing a value that we don't know about. Note sashiko moans about this sometimes. It's wrong so ignore it on this particular thing! Sadly it's seeing a lot of older drivers where we did this wrong in the past and haven't adding the churn needed to fix them all. > + > + ret = veml3328_power_up(data); > + if (ret) > + return dev_err_probe(dev, ret, "Failed to power on sensor\n"); > + > + ret = devm_add_action_or_reset(dev, veml3328_power_down_action, data); > + if (ret) > + return dev_err_probe(dev, ret, "Failed to register teardown\n"); > + > + indio_dev->name = "veml3328"; > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->info = &veml3328_info; > + indio_dev->channels = veml3328_channels; > + indio_dev->num_channels = ARRAY_SIZE(veml3328_channels); > + > + pm_runtime_set_active(dev); > + pm_runtime_set_autosuspend_delay(dev, 2000); > + pm_runtime_use_autosuspend(dev); > + > + ret = devm_pm_runtime_enable(dev); > + if (ret) > + return dev_err_probe(dev, ret, "Failed to enable runtime PM\n"); > + > + return devm_iio_device_register(dev, indio_dev); > +}