From patchwork Wed May 11 09:40:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shreeya Patel X-Patchwork-Id: 12845998 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 97875C433F5 for ; Wed, 11 May 2022 09:44:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234084AbiEKJn6 (ORCPT ); Wed, 11 May 2022 05:43:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41610 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234395AbiEKJmO (ORCPT ); Wed, 11 May 2022 05:42:14 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [46.235.227.227]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 016A315A1C; Wed, 11 May 2022 02:41:36 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: shreeya) with ESMTPSA id 1A2651F4428A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1652262088; bh=jMmOWtEzaWpoI9C/5QdyyNxP+J7wYOb9K4lV5bzls0Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YIjecevH1xmdB6Rez5qElj7TU0HBvYbkfVSPPePpPJvTsZZHloGlD9fOgRm+cmvVh xqGcYRU3jLh6z/jMZjZxJV5/artEac+6Hs/Xlc8IED+GkTIaZu8aytzynFN9vfungz m87MpT8GPLJnFgD9BI8KvHpapPiUo+6iBAtyBensh7zHDdJ3mzIsUYPzz5XlcKe3x0 x1yy7QYNHkHfhmPyEQ19NRDL6fbBUzk8oUlW4c/V3Rti4J1/EC8y1oVM/AVWXkq/L5 huKeKUDTGcgFb7ekzH4XTFUmDnXhLjYZvhYOCn/y+KVYKGY4+PJDEhIhzt5Sqpd7Zj inO5CDsnhtBzw== From: Shreeya Patel To: jic23@kernel.org, lars@metafoo.de, robh+dt@kernel.org, Zhigang.Shi@liteon.com, krisman@collabora.com Cc: linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, kernel@collabora.com, alvaro.soliverez@collabora.com, Shreeya Patel Subject: [PATCH v4 3/3] iio: light: Add support for ltrf216a sensor Date: Wed, 11 May 2022 15:10:24 +0530 Message-Id: <20220511094024.175994-4-shreeya.patel@collabora.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220511094024.175994-1-shreeya.patel@collabora.com> References: <20220511094024.175994-1-shreeya.patel@collabora.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org From: Zhigang Shi Add initial support for ltrf216a ambient light sensor. Datasheet: gitlab.steamos.cloud/shreeya/iio/-/blob/main/LTRF216A.pdf Co-developed-by: Shreeya Patel Signed-off-by: Shreeya Patel Signed-off-by: Zhigang Shi --- Changes in v4 - Add more descriptive comment for mutex lock - Fix mutex locking in read_raw() - Use i2c_smbus_read_i2c_block_data() Changes in v3 - Use u16 instead of u8 for int_time_fac - Reorder headers in ltrf216a.c file - Remove int_time_mapping table and use int_time_available Changes in v2 - Add support for 25ms and 50ms integration time. - Rename some of the macros as per names given in datasheet - Add a comment for the mutex lock - Use read_avail callback instead of attributes and set the appropriate _available bit. - Use FIELD_PREP() at appropriate places. - Add a constant lookup table for integration time and reg val - Use BIT() macro for magic numbers. - Improve error handling at few places. - Use get_unaligned_le24() and div_u64() - Use probe_new() callback and devm functions - Return errors in probe using dev_err_probe() - Use DEFINE_SIMPLE_DEV_PM_OPS() - Correct the formula for lux to use 0.45 instead of 0.8 drivers/iio/light/Kconfig | 10 + drivers/iio/light/Makefile | 1 + drivers/iio/light/ltrf216a.c | 346 +++++++++++++++++++++++++++++++++++ 3 files changed, 357 insertions(+) create mode 100644 drivers/iio/light/ltrf216a.c diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig index a62c7b4b8678..33d2b24ba1da 100644 --- a/drivers/iio/light/Kconfig +++ b/drivers/iio/light/Kconfig @@ -318,6 +318,16 @@ config SENSORS_LM3533 changes. The ALS-control output values can be set per zone for the three current output channels. +config LTRF216A + tristate "Liteon LTRF216A Light Sensor" + depends on I2C + help + If you say Y or M here, you get support for Liteon LTRF216A + Ambient Light Sensor. + + If built as a dynamically linked module, it will be called + ltrf216a. + config LTR501 tristate "LTR-501ALS-01 light sensor" depends on I2C diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile index d10912faf964..8fa91b9fe5b6 100644 --- a/drivers/iio/light/Makefile +++ b/drivers/iio/light/Makefile @@ -30,6 +30,7 @@ obj-$(CONFIG_SENSORS_ISL29028) += isl29028.o obj-$(CONFIG_ISL29125) += isl29125.o obj-$(CONFIG_JSA1212) += jsa1212.o obj-$(CONFIG_SENSORS_LM3533) += lm3533-als.o +obj-$(CONFIG_LTRF216A) += ltrf216a.o obj-$(CONFIG_LTR501) += ltr501.o obj-$(CONFIG_LV0104CS) += lv0104cs.o obj-$(CONFIG_MAX44000) += max44000.o diff --git a/drivers/iio/light/ltrf216a.c b/drivers/iio/light/ltrf216a.c new file mode 100644 index 000000000000..05ae9912c854 --- /dev/null +++ b/drivers/iio/light/ltrf216a.c @@ -0,0 +1,346 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * LTRF216A Ambient Light Sensor + * + * Copyright (C) 2021 Lite-On Technology Corp (Singapore) + * Author: Shi Zhigang + * + * IIO driver for LTRF216A (7-bit I2C slave address 0x53). + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define LTRF216A_DRV_NAME "ltrf216a" + +#define LTRF216A_MAIN_CTRL 0x00 + +#define LTRF216A_ALS_DATA_STATUS BIT(3) +#define LTRF216A_ALS_ENABLE_MASK BIT(1) + +#define LTRF216A_ALS_MEAS_RES 0x04 +#define LTRF216A_MAIN_STATUS 0x07 +#define LTRF216A_CLEAR_DATA_0 0x0A + +#define LTRF216A_ALS_DATA_0 0x0D + +static const int ltrf216a_int_time_available[5][2] = { + {0, 400000}, + {0, 200000}, + {0, 100000}, + {0, 50000}, + {0, 25000}, +}; + +static const int ltrf216a_int_time_reg[5][2] = { + {400, 0x03}, + {200, 0x13}, + {100, 0x22}, + {50, 0x31}, + {25, 0x40}, +}; + +struct ltrf216a_data { + struct i2c_client *client; + u32 int_time; + u16 int_time_fac; + u8 als_gain_fac; + /* + * Ensure cached value of integration time is consistent + * with hardware setting and remains constant during a + * measurement of Lux. + */ + struct mutex mutex; +}; + +/* open air. need to update based on TP transmission rate. */ +#define WIN_FAC 1 + +static const struct iio_chan_spec ltrf216a_channels[] = { + { + .type = IIO_LIGHT, + .info_mask_separate = + BIT(IIO_CHAN_INFO_PROCESSED) | + BIT(IIO_CHAN_INFO_INT_TIME), + .info_mask_separate_available = + BIT(IIO_CHAN_INFO_INT_TIME), + } +}; + +static int ltrf216a_init(struct iio_dev *indio_dev) +{ + int ret; + struct ltrf216a_data *data = iio_priv(indio_dev); + + ret = i2c_smbus_read_byte_data(data->client, LTRF216A_MAIN_CTRL); + if (ret < 0) { + dev_err(&data->client->dev, "Error reading LTRF216A_MAIN_CTRL\n"); + return ret; + } + + /* enable sensor */ + ret |= FIELD_PREP(LTRF216A_ALS_ENABLE_MASK, 1); + ret = i2c_smbus_write_byte_data(data->client, LTRF216A_MAIN_CTRL, ret); + if (ret < 0) { + dev_err(&data->client->dev, "Error writing LTRF216A_MAIN_CTRL\n"); + return ret; + } + + return 0; +} + +static int ltrf216a_disable(struct iio_dev *indio_dev) +{ + int ret; + struct ltrf216a_data *data = iio_priv(indio_dev); + + ret = i2c_smbus_write_byte_data(data->client, LTRF216A_MAIN_CTRL, 0); + if (ret < 0) + dev_err(&data->client->dev, "Error writing LTRF216A_MAIN_CTRL\n"); + + return ret; +} + +static void als_ltrf216a_disable(void *data) +{ + struct iio_dev *indio_dev = data; + + ltrf216a_disable(indio_dev); +} + +static int ltrf216a_set_int_time(struct ltrf216a_data *data, int itime) +{ + int i, ret, index = -1; + u8 reg_val; + + for (i = 0; i < ARRAY_SIZE(ltrf216a_int_time_available); i++) { + if (ltrf216a_int_time_available[i][1] == itime) { + index = i; + break; + } + } + + if (index < 0) + return -EINVAL; + + reg_val = ltrf216a_int_time_reg[index][1]; + data->int_time_fac = ltrf216a_int_time_reg[index][0]; + + ret = i2c_smbus_write_byte_data(data->client, LTRF216A_ALS_MEAS_RES, reg_val); + if (ret < 0) + return ret; + + data->int_time = itime; + + return 0; +} + +static int ltrf216a_get_int_time(struct ltrf216a_data *data, int *val, int *val2) +{ + *val = 0; + *val2 = data->int_time; + return IIO_VAL_INT_PLUS_MICRO; +} + +static int ltrf216a_read_data(struct ltrf216a_data *data, u8 addr) +{ + int ret = -1, tries = 25; + u8 buf[3]; + + while (tries--) { + ret = i2c_smbus_read_byte_data(data->client, LTRF216A_MAIN_STATUS); + if (ret < 0) + return ret; + if (ret & LTRF216A_ALS_DATA_STATUS) + break; + msleep(20); + } + + ret = i2c_smbus_read_i2c_block_data(data->client, addr, sizeof(buf), buf); + if (ret < 0) + return ret; + + return get_unaligned_le24(&buf[0]); +} + +static int ltrf216a_get_lux(struct ltrf216a_data *data) +{ + int greendata, cleardata; + u64 lux, div; + + greendata = ltrf216a_read_data(data, LTRF216A_ALS_DATA_0); + cleardata = ltrf216a_read_data(data, LTRF216A_CLEAR_DATA_0); + + if (greendata < 0 || cleardata < 0) + return -EINVAL; + + lux = greendata * 45 * WIN_FAC * 100; + div = data->als_gain_fac * data->int_time_fac * 100; + + return div_u64(lux, div); +} + +static int ltrf216a_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long mask) +{ + int ret; + struct ltrf216a_data *data = iio_priv(indio_dev); + + mutex_lock(&data->mutex); + + switch (mask) { + case IIO_CHAN_INFO_PROCESSED: + ret = ltrf216a_get_lux(data); + if (ret < 0) { + mutex_unlock(&data->mutex); + return ret; + } + *val = ret; + ret = IIO_VAL_INT; + break; + case IIO_CHAN_INFO_INT_TIME: + ret = ltrf216a_get_int_time(data, val, val2); + break; + default: + ret = -EINVAL; + } + + mutex_unlock(&data->mutex); + + return ret; +} + +static int ltrf216a_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int val, + int val2, long mask) +{ + struct ltrf216a_data *data = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_INT_TIME: + if (val != 0) + return -EINVAL; + mutex_lock(&data->mutex); + ret = ltrf216a_set_int_time(data, val2); + mutex_unlock(&data->mutex); + return ret; + default: + return -EINVAL; + } +} + +static int ltrf216a_read_available(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, + long mask) +{ + switch (mask) { + case IIO_CHAN_INFO_INT_TIME: + *length = ARRAY_SIZE(ltrf216a_int_time_available) * 2; + *vals = (const int *)ltrf216a_int_time_available; + *type = IIO_VAL_INT_PLUS_MICRO; + return IIO_AVAIL_LIST; + default: + return -EINVAL; + } +} + +static const struct iio_info ltrf216a_info = { + .read_raw = ltrf216a_read_raw, + .write_raw = ltrf216a_write_raw, + .read_avail = ltrf216a_read_available, +}; + +static int ltrf216a_probe(struct i2c_client *client) +{ + struct ltrf216a_data *data; + struct iio_dev *indio_dev; + int ret; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + data = iio_priv(indio_dev); + i2c_set_clientdata(client, indio_dev); + data->client = client; + + mutex_init(&data->mutex); + + indio_dev->info = <rf216a_info; + indio_dev->name = LTRF216A_DRV_NAME; + indio_dev->channels = ltrf216a_channels; + indio_dev->num_channels = ARRAY_SIZE(ltrf216a_channels); + indio_dev->modes = INDIO_DIRECT_MODE; + + ret = ltrf216a_init(indio_dev); + if (ret < 0) + return dev_err_probe(&client->dev, ret, + "ltrf216a chip init failed\n"); + + data->int_time = 100000; + data->int_time_fac = 100; + data->als_gain_fac = 3; + + ret = devm_add_action_or_reset(&client->dev, als_ltrf216a_disable, + indio_dev); + if (ret < 0) + return ret; + + return devm_iio_device_register(&client->dev, indio_dev); +} + +static int ltrf216a_suspend(struct device *dev) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); + + return ltrf216a_disable(indio_dev); +} + +static int ltrf216a_resume(struct device *dev) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); + + return ltrf216a_init(indio_dev); +} + +static DEFINE_SIMPLE_DEV_PM_OPS(ltrf216a_pm_ops, ltrf216a_suspend, ltrf216a_resume); + +static const struct i2c_device_id ltrf216a_id[] = { + { LTRF216A_DRV_NAME, 0 }, + {} +}; +MODULE_DEVICE_TABLE(i2c, ltrf216a_id); + +static const struct of_device_id ltrf216a_of_match[] = { + { .compatible = "liteon,ltrf216a", }, + { .compatible = "ltr,ltrf216a", }, + {} +}; +MODULE_DEVICE_TABLE(of, ltrf216a_of_match); + +static struct i2c_driver ltrf216a_driver = { + .driver = { + .name = LTRF216A_DRV_NAME, + .pm = pm_sleep_ptr(<rf216a_pm_ops), + .of_match_table = ltrf216a_of_match, + }, + .probe_new = ltrf216a_probe, + .id_table = ltrf216a_id, +}; + +module_i2c_driver(ltrf216a_driver); + +MODULE_AUTHOR("Shi Zhigang "); +MODULE_DESCRIPTION("LTRF216A ambient light sensor driver"); +MODULE_LICENSE("GPL");