From patchwork Tue Oct 22 13:09:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rishi Gupta X-Patchwork-Id: 11204397 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A984314E5 for ; Tue, 22 Oct 2019 13:10:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 60B942184C for ; Tue, 22 Oct 2019 13:10:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="q25mshnP" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731969AbfJVNKQ (ORCPT ); Tue, 22 Oct 2019 09:10:16 -0400 Received: from mail-pf1-f176.google.com ([209.85.210.176]:32808 "EHLO mail-pf1-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727582AbfJVNKQ (ORCPT ); Tue, 22 Oct 2019 09:10:16 -0400 Received: by mail-pf1-f176.google.com with SMTP id c184so1120224pfb.0; Tue, 22 Oct 2019 06:10:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=Hcww9E5FwlqPw1EwXzsesMJD+0x78ac/FqH4V5WuuKw=; b=q25mshnPMlGGEDEcCBinSnL701keI4p+kKpVfG0bSYzwcRl2Kr0xERwk8RKikkY9PZ 53PwGZCLi0QQ9WSjgEPobkG6pTgLRRJorIekTMLHoIjOqDsTrjewagAAsvMhXdfCCmlT fGe19zvkqrbfRGiWHq9P3Bjl9ejwOoi8XP7lJmyG3WKHnwEks58t2IwLKnR7x2PIcCMn 1clRGqGTqYeHejDkzU1g1N0TIvE2dHI3MlK2IeFESHvaNHbcEHEW0yViDMhOYxmXooOE 5jfauSKGNO3QO9IAPHmPUai8+w2Vdir1gej9JzfixdJczeeT3/rPOtYVs6TsjjyWEAbJ RHqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=Hcww9E5FwlqPw1EwXzsesMJD+0x78ac/FqH4V5WuuKw=; b=IIn3Ve5mtEf4W4h85RLSE5U90tSqqULQL+SHbUaY48weMUlaHcRHh11e+AMZ/76098 xbGq3mJiIqqexQ7kf+7hVR15LVpN377tU4CapQTD5q9SFQ5i7vX9YKch68K4qGhEwOop hJAEybfUyzNg4+otDUAKlGvDaTe5hI4bvk+65/FDFjauHABaYac4Cqmzp3Egwj5CJTYB kMHzsNZsveuVax9PvZ/lOjjx+6y1mJtCOOTcBvfP9O8zuEKfqP55Jx7v9nJisgQP9f27 YlhNuDj2y9Jgwvf6A8i26VK8kndTQO43j8ilJsVbogE4yCVkTe6N77zi3QmQtF7TXoOw p7xg== X-Gm-Message-State: APjAAAVXT0AxYR9+larEaND9jSBDtcLH3oHbZXirl9ZDxlp6Gbl+nTqQ u6r2jcnNAn0neDLPxeM0unw= X-Google-Smtp-Source: APXvYqyI7RbLU0HJ5P6G09wh+zk8as4+x0SWd9NnYxGpsM5QmzR/451bon97DCiGMzhvKQGVqe8VXA== X-Received: by 2002:aa7:9d89:: with SMTP id f9mr4298223pfq.25.1571749811110; Tue, 22 Oct 2019 06:10:11 -0700 (PDT) Received: from localhost.localdomain ([106.51.109.161]) by smtp.gmail.com with ESMTPSA id m9sm18327773pjf.11.2019.10.22.06.10.06 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 22 Oct 2019 06:10:10 -0700 (PDT) From: Rishi Gupta To: jic23@kernel.org Cc: knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, gregkh@linuxfoundation.org, tglx@linutronix.de, allison@lohutok.net, alexios.zavras@intel.com, angus@akkea.ca, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, mark.rutland@arm.com, devicetree@vger.kernel.org, Rishi Gupta Subject: [PATCH v5 1/3] iio: light: add driver for veml6030 ambient light sensor Date: Tue, 22 Oct 2019 18:39:56 +0530 Message-Id: <1571749796-8608-1-git-send-email-gupt21@gmail.com> X-Mailer: git-send-email 2.7.4 Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org veml6030 is an ambient light sensor from Vishay semiconductors. It has 16-bit resolution, supports both ambient light measurement and white channel which is more responsive to wider wavelength spectrum. It has flexible power saving, integration time and gain options. Communication with host is over I2C. Signed-off-by: Rishi Gupta --- Changes in v5: * Removed setting val2 when returning IIO_VAL_INT * Removed redundant return from veml6030_read_raw() * Set 4000 as min time in usleep_range(4000, 4002) Changes in v4: * None Changes in v3: * Added appnote link in topmost comments section * Dropped 'return ret' statements wherever not needed * Removed .scan_index from channel specifications, not needed * If irq is not enabled, events interfaces are not exposed now * Return IRQ_NONE for spurious interrupt * Removed CONFIG_PM, added __maybe_unused in power routines * Removed of_match_ptr when specifying DT device id to match * Corrected & documented sequence in veml6030_write_interrupt_config() * Removed veml6030_remove() & added devm_add_action_or_reset functionality * Added support to read integration time, gain, thresholds, period * Removed including mutex.h not needed * Set 100 ms integration & 1/8 gain during probe for better accuracy * Used IIO_CONST_ATTR to create sysfs entries "_available" * Minor cosmetics like everything in lower case Changes in v2: * Added comma after CH_WHITE in enum veml6030_chan so it can be extended * Removed .scan_type as driver doesn't use buffered mode * Removed iio_device_unregister() as kernel will take care of cleaning drivers/iio/light/Kconfig | 11 + drivers/iio/light/Makefile | 1 + drivers/iio/light/veml6030.c | 839 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 851 insertions(+) create mode 100644 drivers/iio/light/veml6030.c diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig index 4a1a883..f9d27ef 100644 --- a/drivers/iio/light/Kconfig +++ b/drivers/iio/light/Kconfig @@ -496,6 +496,17 @@ config VCNL4035 To compile this driver as a module, choose M here: the module will be called vcnl4035. +config VEML6030 + tristate "VEML6030 ambient light sensor" + select REGMAP_I2C + depends on I2C + help + Say Y here if you want to build a driver for the Vishay VEML6030 + ambient light sensor (ALS). + + To compile this driver as a module, choose M here: the + module will be called veml6030. + config VEML6070 tristate "VEML6070 UV A light sensor" depends on I2C diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile index 00d1f9b..5e0c40b 100644 --- a/drivers/iio/light/Makefile +++ b/drivers/iio/light/Makefile @@ -48,6 +48,7 @@ obj-$(CONFIG_TSL4531) += tsl4531.o obj-$(CONFIG_US5182D) += us5182d.o obj-$(CONFIG_VCNL4000) += vcnl4000.o obj-$(CONFIG_VCNL4035) += vcnl4035.o +obj-$(CONFIG_VEML6030) += veml6030.o obj-$(CONFIG_VEML6070) += veml6070.o obj-$(CONFIG_VL6180) += vl6180.o obj-$(CONFIG_ZOPT2201) += zopt2201.o diff --git a/drivers/iio/light/veml6030.c b/drivers/iio/light/veml6030.c new file mode 100644 index 0000000..6b808d8 --- /dev/null +++ b/drivers/iio/light/veml6030.c @@ -0,0 +1,839 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * VEML6030 Ambient Light Sensor + * + * Copyright (c) 2019, Rishi Gupta + * + * Datasheet: https://www.vishay.com/docs/84366/veml6030.pdf + * Appnote-84367: https://www.vishay.com/docs/84367/designingveml6030.pdf + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Device registers */ +#define VEML6030_REG_ALS_CONF 0x00 +#define VEML6030_REG_ALS_WH 0x01 +#define VEML6030_REG_ALS_WL 0x02 +#define VEML6030_REG_ALS_PSM 0x03 +#define VEML6030_REG_ALS_DATA 0x04 +#define VEML6030_REG_WH_DATA 0x05 +#define VEML6030_REG_ALS_INT 0x06 + +/* Bit masks for specific functionality */ +#define VEML6030_ALS_IT GENMASK(9, 6) +#define VEML6030_PSM GENMASK(2, 1) +#define VEML6030_ALS_PERS GENMASK(5, 4) +#define VEML6030_ALS_GAIN GENMASK(12, 11) +#define VEML6030_PSM_EN BIT(0) +#define VEML6030_INT_TH_LOW BIT(15) +#define VEML6030_INT_TH_HIGH BIT(14) +#define VEML6030_ALS_INT_EN BIT(1) +#define VEML6030_ALS_SD BIT(0) + +/* + * The resolution depends on both gain and integration time. The + * cur_resolution stores one of the resolution mentioned in the + * table during startup and gets updated whenever integration time + * or gain is changed. + * + * Table 'resolution and maximum detection range' in appnote 84367 + * is visualized as a 2D array. The cur_gain stores index of gain + * in this table (0-3) while the cur_integration_time holds index + * of integration time (0-5). + */ +struct veml6030_data { + struct i2c_client *client; + struct regmap *regmap; + int cur_resolution; + int cur_gain; + int cur_integration_time; +}; + +/* Integration time available in seconds */ +static IIO_CONST_ATTR(in_illuminance_integration_time_available, + "0.025 0.05 0.1 0.2 0.4 0.8"); + +/* + * Scale is 1/gain. Value 0.125 is ALS gain x (1/8), 0.25 is + * ALS gain x (1/4), 1.0 = ALS gain x 1 and 2.0 is ALS gain x 2. + */ +static IIO_CONST_ATTR(in_illuminance_scale_available, + "0.125 0.25 1.0 2.0"); + +static struct attribute *veml6030_attributes[] = { + &iio_const_attr_in_illuminance_integration_time_available.dev_attr.attr, + &iio_const_attr_in_illuminance_scale_available.dev_attr.attr, + NULL +}; + +static const struct attribute_group veml6030_attr_group = { + .attrs = veml6030_attributes, +}; + +/* + * Persistence = 1/2/4/8 x integration time + * Minimum time for which light readings must stay above configured + * threshold to assert interrupt. + */ +static IIO_CONST_ATTR(in_illuminance_period_available, + "1 2 4 8"); + +static struct attribute *veml6030_event_attributes[] = { + &iio_const_attr_in_illuminance_period_available.dev_attr.attr, + NULL +}; + +static const struct attribute_group veml6030_event_attr_group = { + .attrs = veml6030_event_attributes, +}; + +static int veml6030_als_pwr_on(struct veml6030_data *data) +{ + return regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF, + VEML6030_ALS_SD, 0); +} + +static int veml6030_als_shut_down(struct veml6030_data *data) +{ + return regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF, + VEML6030_ALS_SD, 1); +} + +static void veml6030_als_shut_down_action(void *data) +{ + veml6030_als_shut_down(data); +} + +static const struct iio_event_spec veml6030_event_spec[] = { + { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_RISING, + .mask_separate = BIT(IIO_EV_INFO_VALUE), + }, { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_FALLING, + .mask_separate = BIT(IIO_EV_INFO_VALUE), + }, { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_EITHER, + .mask_separate = BIT(IIO_EV_INFO_PERIOD), + }, { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_EITHER, + .mask_separate = BIT(IIO_EV_INFO_ENABLE), + }, +}; + +/* Channel number */ +enum veml6030_chan { + CH_ALS, + CH_WHITE, +}; + +static const struct iio_chan_spec veml6030_channels[] = { + { + .type = IIO_LIGHT, + .channel = CH_ALS, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_PROCESSED) | + BIT(IIO_CHAN_INFO_INT_TIME) | + BIT(IIO_CHAN_INFO_SCALE), + .event_spec = veml6030_event_spec, + .num_event_specs = ARRAY_SIZE(veml6030_event_spec), + }, + { + .type = IIO_INTENSITY, + .channel = CH_WHITE, + .modified = 1, + .channel2 = IIO_MOD_LIGHT_BOTH, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_PROCESSED), + }, +}; + +static const struct regmap_config veml6030_regmap_config = { + .name = "veml6030_regmap", + .reg_bits = 8, + .val_bits = 16, + .max_register = VEML6030_REG_ALS_INT, + .val_format_endian = REGMAP_ENDIAN_LITTLE, +}; + +static int veml6030_read_persistence(struct iio_dev *indio_dev, + int *val, int *val2) +{ + int ret, reg; + struct veml6030_data *data = iio_priv(indio_dev); + + ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, ®); + if (ret) { + dev_err(&data->client->dev, + "can't als configuration register %d\n", ret); + return ret; + } + + *val = 1 << ((reg >> 3) & 0x03); + return IIO_VAL_INT; +} + +static int veml6030_write_persistence(struct iio_dev *indio_dev, + int val, int val2) +{ + int ret; + struct veml6030_data *data = iio_priv(indio_dev); + + if (val < 0 || val > 8 || hweight8(val) != 1 || val2) + return -EINVAL; + + ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF, + VEML6030_ALS_PERS, val << 4); + if (ret) + dev_err(&data->client->dev, + "can't set persistence value %d\n", ret); + + return ret; +} + +static int veml6030_set_als_gain(struct iio_dev *indio_dev, + int val, int val2) +{ + int ret, new_gain, gain_idx; + struct veml6030_data *data = iio_priv(indio_dev); + + if (val == 0 && val2 == 125000) { + new_gain = 0x1000; /* 0x02 << 11 */ + gain_idx = 3; + } else if (val == 0 && val2 == 250000) { + new_gain = 0x1800; + gain_idx = 2; + } else if (val == 1 && val2 == 0) { + new_gain = 0x00; + gain_idx = 1; + } else if (val == 2 && val2 == 0) { + new_gain = 0x800; + gain_idx = 0; + } else { + return -EINVAL; + } + + ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF, + VEML6030_ALS_GAIN, new_gain); + if (ret) { + dev_err(&data->client->dev, + "can't set als gain %d\n", ret); + return ret; + } + + /* + * Cache currently set gain & update resolution. For every + * increase in the gain to next level, resolution is halved + * and vice-versa. + */ + if (data->cur_gain < gain_idx) + data->cur_resolution <<= gain_idx - data->cur_gain; + else if (data->cur_gain > gain_idx) + data->cur_resolution >>= data->cur_gain - gain_idx; + + data->cur_gain = gain_idx; + + return ret; +} + +static int veml6030_get_als_gain(struct iio_dev *indio_dev, + int *val, int *val2) +{ + int ret, reg; + struct veml6030_data *data = iio_priv(indio_dev); + + ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, ®); + if (ret) { + dev_err(&data->client->dev, + "can't als configuration register %d\n", ret); + return ret; + } + + switch ((reg >> 11) & 0x03) { + case 0: + *val = 1; + *val2 = 0; + break; + case 1: + *val = 2; + *val2 = 0; + break; + case 2: + *val = 0; + *val2 = 125000; + break; + case 3: + *val = 0; + *val2 = 250000; + break; + default: + return -EINVAL; + } + + return IIO_VAL_INT_PLUS_MICRO; +} + +static int veml6030_read_thresh(struct iio_dev *indio_dev, + int *val, int *val2, int dir) +{ + int ret, reg; + struct veml6030_data *data = iio_priv(indio_dev); + + if (dir == IIO_EV_DIR_RISING) + ret = regmap_read(data->regmap, VEML6030_REG_ALS_WH, ®); + else + ret = regmap_read(data->regmap, VEML6030_REG_ALS_WL, ®); + if (ret) { + dev_err(&data->client->dev, + "can't read als threshold value %d\n", ret); + return ret; + } + + *val = reg & 0xffff; + return IIO_VAL_INT; +} + +static int veml6030_write_thresh(struct iio_dev *indio_dev, + int val, int val2, int dir) +{ + int ret; + struct veml6030_data *data = iio_priv(indio_dev); + + if (val > 0xFFFF || val < 0 || val2) + return -EINVAL; + + if (dir == IIO_EV_DIR_RISING) { + ret = regmap_write(data->regmap, VEML6030_REG_ALS_WH, val); + if (ret) + dev_err(&data->client->dev, + "can't set high threshold %d\n", ret); + } else { + ret = regmap_write(data->regmap, VEML6030_REG_ALS_WL, val); + if (ret) + dev_err(&data->client->dev, + "can't set low threshold %d\n", ret); + } + + return ret; +} + +static int veml6030_get_intgrn_tm(struct iio_dev *indio_dev, + int *val, int *val2) +{ + int ret, reg; + struct veml6030_data *data = iio_priv(indio_dev); + + ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, ®); + if (ret) { + dev_err(&data->client->dev, + "can't als configuration register %d\n", ret); + return ret; + } + + switch ((reg >> 6) & 0xF) { + case 0: + *val2 = 100000; + break; + case 1: + *val2 = 200000; + break; + case 2: + *val2 = 400000; + break; + case 3: + *val2 = 800000; + break; + case 8: + *val2 = 50000; + break; + case 12: + *val2 = 25000; + break; + default: + return -EINVAL; + } + + *val = 0; + return IIO_VAL_INT_PLUS_MICRO; +} + +static int veml6030_set_intgrn_tm(struct iio_dev *indio_dev, + int val, int val2) +{ + int ret, new_int_time, int_idx; + struct veml6030_data *data = iio_priv(indio_dev); + + if (val) + return -EINVAL; + + switch (val2) { + case 25000: + new_int_time = 0x300; + int_idx = 5; + break; + case 50000: + new_int_time = 0x200; + int_idx = 4; + break; + case 100000: + new_int_time = 0x00; + int_idx = 3; + break; + case 200000: + new_int_time = 0x40; + int_idx = 2; + break; + case 400000: + new_int_time = 0x80; + int_idx = 1; + break; + case 800000: + new_int_time = 0xC0; + int_idx = 0; + break; + default: + return -EINVAL; + } + + ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF, + VEML6030_ALS_IT, new_int_time); + if (ret) { + dev_err(&data->client->dev, + "can't update als integration time %d\n", ret); + return ret; + } + + /* + * Cache current integration time and update resolution. For every + * increase in integration time to next level, resolution is halved + * and vice-versa. + */ + if (data->cur_integration_time < int_idx) + data->cur_resolution <<= int_idx - data->cur_integration_time; + else if (data->cur_integration_time > int_idx) + data->cur_resolution >>= data->cur_integration_time - int_idx; + + data->cur_integration_time = int_idx; + + return ret; +} + +/* + * Provide both raw as well as light reading in lux. + * light (in lux) = resolution * raw reading + */ +static int veml6030_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long mask) +{ + int ret, reg; + struct veml6030_data *data = iio_priv(indio_dev); + struct regmap *regmap = data->regmap; + struct device *dev = &data->client->dev; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + case IIO_CHAN_INFO_PROCESSED: + switch (chan->type) { + case IIO_LIGHT: + ret = regmap_read(regmap, VEML6030_REG_ALS_DATA, ®); + if (ret < 0) { + dev_err(dev, "can't read als data %d\n", ret); + return ret; + } + if (mask == IIO_CHAN_INFO_PROCESSED) { + *val = (reg * data->cur_resolution) / 10000; + *val2 = (reg * data->cur_resolution) % 10000; + return IIO_VAL_INT_PLUS_MICRO; + } + *val = reg; + return IIO_VAL_INT; + case IIO_INTENSITY: + ret = regmap_read(regmap, VEML6030_REG_WH_DATA, ®); + if (ret < 0) { + dev_err(dev, "can't read white data %d\n", ret); + return ret; + } + if (mask == IIO_CHAN_INFO_PROCESSED) { + *val = (reg * data->cur_resolution) / 10000; + *val2 = (reg * data->cur_resolution) % 10000; + return IIO_VAL_INT_PLUS_MICRO; + } + *val = reg; + return IIO_VAL_INT; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_INT_TIME: + if (chan->type == IIO_LIGHT) + return veml6030_get_intgrn_tm(indio_dev, val, val2); + return -EINVAL; + case IIO_CHAN_INFO_SCALE: + if (chan->type == IIO_LIGHT) + return veml6030_get_als_gain(indio_dev, val, val2); + return -EINVAL; + default: + return -EINVAL; + } +} + +static int veml6030_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + switch (mask) { + case IIO_CHAN_INFO_INT_TIME: + switch (chan->type) { + case IIO_LIGHT: + return veml6030_set_intgrn_tm(indio_dev, val, val2); + default: + return -EINVAL; + } + case IIO_CHAN_INFO_SCALE: + switch (chan->type) { + case IIO_LIGHT: + return veml6030_set_als_gain(indio_dev, val, val2); + default: + return -EINVAL; + } + default: + return -EINVAL; + } +} + +static int veml6030_read_event_val(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, enum iio_event_type type, + enum iio_event_direction dir, enum iio_event_info info, + int *val, int *val2) +{ + switch (info) { + case IIO_EV_INFO_VALUE: + switch (dir) { + case IIO_EV_DIR_RISING: + case IIO_EV_DIR_FALLING: + return veml6030_read_thresh(indio_dev, val, val2, dir); + default: + return -EINVAL; + } + break; + case IIO_EV_INFO_PERIOD: + return veml6030_read_persistence(indio_dev, val, val2); + default: + return -EINVAL; + } +} + +static int veml6030_write_event_val(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, enum iio_event_type type, + enum iio_event_direction dir, enum iio_event_info info, + int val, int val2) +{ + switch (info) { + case IIO_EV_INFO_VALUE: + return veml6030_write_thresh(indio_dev, val, val2, dir); + case IIO_EV_INFO_PERIOD: + return veml6030_write_persistence(indio_dev, val, val2); + default: + return -EINVAL; + } +} + +static int veml6030_read_interrupt_config(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, enum iio_event_type type, + enum iio_event_direction dir) +{ + int ret, reg; + struct veml6030_data *data = iio_priv(indio_dev); + + ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, ®); + if (ret) { + dev_err(&data->client->dev, + "can't read als conf register %d\n", ret); + return ret; + } + + if (reg & VEML6030_ALS_INT_EN) + return 1; + else + return 0; +} + +/* + * Sensor should not be measuring light when interrupt is configured. + * Therefore correct sequence to configure interrupt functionality is: + * shut down -> enable/disable interrupt -> power on + * + * state = 1 enables interrupt, state = 0 disables interrupt + */ +static int veml6030_write_interrupt_config(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, enum iio_event_type type, + enum iio_event_direction dir, int state) +{ + int ret; + struct veml6030_data *data = iio_priv(indio_dev); + + if (state < 0 || state > 1) + return -EINVAL; + + ret = veml6030_als_shut_down(data); + if (ret < 0) { + dev_err(&data->client->dev, + "can't disable als to configure interrupt %d\n", ret); + return ret; + } + + /* enable interrupt + power on */ + ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF, + VEML6030_ALS_INT_EN | VEML6030_ALS_SD, state << 1); + if (ret) + dev_err(&data->client->dev, + "can't enable interrupt & poweron als %d\n", ret); + + return ret; +} + +static const struct iio_info veml6030_info = { + .read_raw = veml6030_read_raw, + .write_raw = veml6030_write_raw, + .read_event_value = veml6030_read_event_val, + .write_event_value = veml6030_write_event_val, + .read_event_config = veml6030_read_interrupt_config, + .write_event_config = veml6030_write_interrupt_config, + .attrs = &veml6030_attr_group, + .event_attrs = &veml6030_event_attr_group, +}; + +static const struct iio_info veml6030_info_no_irq = { + .read_raw = veml6030_read_raw, + .write_raw = veml6030_write_raw, + .attrs = &veml6030_attr_group, +}; + +static irqreturn_t veml6030_event_handler(int irq, void *private) +{ + int ret, reg, evtdir; + struct iio_dev *indio_dev = private; + struct veml6030_data *data = iio_priv(indio_dev); + + ret = regmap_read(data->regmap, VEML6030_REG_ALS_INT, ®); + if (ret) { + dev_err(&data->client->dev, + "can't read als interrupt register %d\n", ret); + return IRQ_HANDLED; + } + + /* Spurious interrupt handling */ + if (!(reg & (VEML6030_INT_TH_HIGH | VEML6030_INT_TH_LOW))) + return IRQ_NONE; + + if (reg & VEML6030_INT_TH_HIGH) + evtdir = IIO_EV_DIR_RISING; + else + evtdir = IIO_EV_DIR_FALLING; + + iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, + 0, IIO_EV_TYPE_THRESH, evtdir), + iio_get_time_ns(indio_dev)); + + return IRQ_HANDLED; +} + +/* + * Set ALS gain to 1/8, integration time to 100 ms, PSM to mode 2, + * persistence to 1 x integration time and the threshold + * interrupt disabled by default. First shutdown the sensor, + * update registers and then power on the sensor. + */ +static int veml6030_hw_init(struct iio_dev *indio_dev) +{ + int ret, val; + struct veml6030_data *data = iio_priv(indio_dev); + struct i2c_client *client = data->client; + + ret = veml6030_als_shut_down(data); + if (ret) { + dev_err(&client->dev, "can't shutdown als %d\n", ret); + return ret; + } + + ret = regmap_write(data->regmap, VEML6030_REG_ALS_CONF, 0x1001); + if (ret) { + dev_err(&client->dev, "can't setup als configs %d\n", ret); + return ret; + } + + ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_PSM, + VEML6030_PSM | VEML6030_PSM_EN, 0x03); + if (ret) { + dev_err(&client->dev, "can't setup default PSM %d\n", ret); + return ret; + } + + ret = regmap_write(data->regmap, VEML6030_REG_ALS_WH, 0xFFFF); + if (ret) { + dev_err(&client->dev, "can't setup high threshold %d\n", ret); + return ret; + } + + ret = regmap_write(data->regmap, VEML6030_REG_ALS_WL, 0x0000); + if (ret) { + dev_err(&client->dev, "can't setup low threshold %d\n", ret); + return ret; + } + + ret = veml6030_als_pwr_on(data); + if (ret) { + dev_err(&client->dev, "can't poweron als %d\n", ret); + return ret; + } + + /* Wait 4 ms to let processor & oscillator start correctly */ + usleep_range(4000, 4002); + + /* Clear stale interrupt status bits if any during start */ + ret = regmap_read(data->regmap, VEML6030_REG_ALS_INT, &val); + if (ret < 0) { + dev_err(&client->dev, + "can't clear als interrupt status %d\n", ret); + return ret; + } + + /* Cache currently active measurement parameters */ + data->cur_gain = 3; + data->cur_resolution = 4608; + data->cur_integration_time = 3; + + return ret; +} + +static int veml6030_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int ret; + struct veml6030_data *data; + struct iio_dev *indio_dev; + struct regmap *regmap; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + dev_err(&client->dev, "i2c adapter doesn't support plain i2c\n"); + return -EOPNOTSUPP; + } + + regmap = devm_regmap_init_i2c(client, &veml6030_regmap_config); + if (IS_ERR(regmap)) { + dev_err(&client->dev, "can't setup regmap\n"); + return PTR_ERR(regmap); + } + + 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; + data->regmap = regmap; + + indio_dev->dev.parent = &client->dev; + indio_dev->name = "veml6030"; + indio_dev->channels = veml6030_channels; + indio_dev->num_channels = ARRAY_SIZE(veml6030_channels); + indio_dev->modes = INDIO_DIRECT_MODE; + + if (client->irq) { + ret = devm_request_threaded_irq(&client->dev, client->irq, + NULL, veml6030_event_handler, + IRQF_TRIGGER_LOW | IRQF_ONESHOT, + "veml6030", indio_dev); + if (ret < 0) { + dev_err(&client->dev, + "irq %d request failed\n", client->irq); + return ret; + } + indio_dev->info = &veml6030_info; + } else { + indio_dev->info = &veml6030_info_no_irq; + } + + ret = devm_add_action_or_reset(&client->dev, + veml6030_als_shut_down_action, data); + if (ret < 0) + return ret; + + ret = veml6030_hw_init(indio_dev); + if (ret < 0) + return ret; + + return devm_iio_device_register(&client->dev, indio_dev); +} + +static int __maybe_unused veml6030_runtime_suspend(struct device *dev) +{ + int ret; + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); + struct veml6030_data *data = iio_priv(indio_dev); + + ret = veml6030_als_shut_down(data); + if (ret < 0) + dev_err(&data->client->dev, "can't suspend als %d\n", ret); + + return ret; +} + +static int __maybe_unused veml6030_runtime_resume(struct device *dev) +{ + int ret; + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); + struct veml6030_data *data = iio_priv(indio_dev); + + ret = veml6030_als_pwr_on(data); + if (ret < 0) + dev_err(&data->client->dev, "can't resume als %d\n", ret); + + return ret; +} + +static const struct dev_pm_ops veml6030_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) + SET_RUNTIME_PM_OPS(veml6030_runtime_suspend, + veml6030_runtime_resume, NULL) +}; + +static const struct of_device_id veml6030_of_match[] = { + { .compatible = "vishay,veml6030" }, + { } +}; +MODULE_DEVICE_TABLE(of, veml6030_of_match); + +static const struct i2c_device_id veml6030_id[] = { + { "veml6030", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, veml6030_id); + +static struct i2c_driver veml6030_driver = { + .driver = { + .name = "veml6030", + .of_match_table = veml6030_of_match, + .pm = &veml6030_pm_ops, + }, + .probe = veml6030_probe, + .id_table = veml6030_id, +}; +module_i2c_driver(veml6030_driver); + +MODULE_AUTHOR("Rishi Gupta "); +MODULE_DESCRIPTION("VEML6030 Ambient Light Sensor"); +MODULE_LICENSE("GPL v2"); From patchwork Tue Oct 22 13:11:13 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rishi Gupta X-Patchwork-Id: 11204405 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C561013BD for ; 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Tue, 22 Oct 2019 06:11:23 -0700 (PDT) From: Rishi Gupta To: jic23@kernel.org Cc: knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, gregkh@linuxfoundation.org, tglx@linutronix.de, allison@lohutok.net, alexios.zavras@intel.com, angus@akkea.ca, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, mark.rutland@arm.com, devicetree@vger.kernel.org, Rishi Gupta Subject: [PATCH v5 2/3] dt-bindings: iio: light: add veml6030 ALS bindings Date: Tue, 22 Oct 2019 18:41:13 +0530 Message-Id: <1571749873-8964-1-git-send-email-gupt21@gmail.com> X-Mailer: git-send-email 2.7.4 Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org This commit adds device tree bindings for veml6030 ambient light sensor. Signed-off-by: Rishi Gupta Reviewed-by: Rob Herring --- Changes in v5: * None Changes in v4: * Added enum in reg property * Removed maxItems from reg property Changes in v3: * None Changes in v2: * Corrected grammatical mistake from 'is' to 'are' in description of bindings .../devicetree/bindings/iio/light/veml6030.yaml | 62 ++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/light/veml6030.yaml diff --git a/Documentation/devicetree/bindings/iio/light/veml6030.yaml b/Documentation/devicetree/bindings/iio/light/veml6030.yaml new file mode 100644 index 0000000..0ff9b11 --- /dev/null +++ b/Documentation/devicetree/bindings/iio/light/veml6030.yaml @@ -0,0 +1,62 @@ +# SPDX-License-Identifier: GPL-2.0+ +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iio/light/veml6030.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: VEML6030 Ambient Light Sensor (ALS) + +maintainers: + - Rishi Gupta + +description: | + Bindings for the ambient light sensor veml6030 from Vishay + Semiconductors over an i2c interface. + + Irrespective of whether interrupt is used or not, application + can get the ALS and White channel reading from IIO raw interface. + + If the interrupts are used, application will receive an IIO event + whenever configured threshold is crossed. + + Specifications about the sensor can be found at: + https://www.vishay.com/docs/84366/veml6030.pdf + +properties: + compatible: + enum: + - vishay,veml6030 + + reg: + description: + I2C address of the device. + enum: + - 0x10 # ADDR pin pulled down + - 0x48 # ADDR pin pulled up + + interrupts: + description: + interrupt mapping for IRQ. Configure with IRQ_TYPE_LEVEL_LOW. + Refer to interrupt-controller/interrupts.txt for generic + interrupt client node bindings. + maxItems: 1 + +required: + - compatible + - reg + +examples: + - | + #include + + i2c { + #address-cells = <1>; + #size-cells = <0>; + + light-sensor@10 { + compatible = "vishay,veml6030"; + reg = <0x10>; + interrupts = <12 IRQ_TYPE_LEVEL_LOW>; + }; + }; +... From patchwork Tue Oct 22 13:11:27 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rishi Gupta X-Patchwork-Id: 11204407 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 74B8F13BD for ; Tue, 22 Oct 2019 13:11:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5447A21920 for ; Tue, 22 Oct 2019 13:11:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Za4hspMt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389190AbfJVNLj (ORCPT ); Tue, 22 Oct 2019 09:11:39 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:42316 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732020AbfJVNLi (ORCPT ); Tue, 22 Oct 2019 09:11:38 -0400 Received: by mail-pf1-f194.google.com with SMTP id q12so10629507pff.9; Tue, 22 Oct 2019 06:11:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=MN/TNI8bhievwfVsfEYoH9ojxY2lOhIiY1YrA76NRdk=; b=Za4hspMtXw5UpWM+KsWuknJr9/56jY0+KReCafnA8AELw0CGxDEx98aMmyRQ6phQYk Z+QukVcjtJIEIW8OQ6HsiqNUwmSU2XDlYHTHn4mMD6YSAJ1FcKrl54uvcg045eGFvg6L Yi+YKryT2cjOhYnB3oOoR95h9cdAZjv8Q83/dqXoJg/SooHgLYEzd5sCSbOLhSgkW58z 3EF087HDEPqk6mIPZHbVh8TGepNISLXrNKRklKbN8U28Mk7/KxSvBTMf2K/fuTwtDQuJ 65QWXeW4lF7Bfy7IrGiu4Ul871Y8BgIn7xQImfYKVqdFxQ71A63TvaXJzNsSurl9Gbwm 2n3g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=MN/TNI8bhievwfVsfEYoH9ojxY2lOhIiY1YrA76NRdk=; b=HubBW9BqrsXhjUHHaHqG3wdOvTNAj3HmUQQvfsKZ0kyszWkBsotATIP2mc//OpBidV fN3Famzjpc4NcGKOs6YrXSkUncB4IDZw51Q2wweZoxofQdMoM3kf8lHslvOt1DWuUJPd dC1O4tJ5QxhUruiW1spYCG2ricI5D9LbIKPnxtpghUVNR/ckfCpy6XZb+CYX6SgTeJk2 Uu3FdsQftI1MOnXotkaUM+H5bnwgsboKTR5RnIBWtQEkIZq5283YpiTdLjvK74EzsHSX FC/DlzQvbOROnrGIWnriigDlRyps8pTysz28yZJVS7rvPx+RB6v/39id8t6htOdauLPi Nn0A== X-Gm-Message-State: APjAAAUgvFDpjhQOv7TE1sP4RAB29+gchHL/1YLk4sml+5x3PcsspHOh AsckxucWJWzTL9YaepomTjn+AK0yi0w= X-Google-Smtp-Source: APXvYqxQHwjAgvoTXTtrpwmDoo+sYvTfZpw9uCVDFoLmkhVrfxkFUDbvAq3zIhUfoGd+Zi/ElDFZEw== X-Received: by 2002:a17:90a:9104:: with SMTP id k4mr4592526pjo.39.1571749897780; Tue, 22 Oct 2019 06:11:37 -0700 (PDT) Received: from localhost.localdomain ([106.51.109.161]) by smtp.gmail.com with ESMTPSA id q2sm28407845pfg.144.2019.10.22.06.11.33 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 22 Oct 2019 06:11:37 -0700 (PDT) From: Rishi Gupta To: jic23@kernel.org Cc: knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, gregkh@linuxfoundation.org, tglx@linutronix.de, allison@lohutok.net, alexios.zavras@intel.com, angus@akkea.ca, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, Rishi Gupta Subject: [PATCH v5 3/3] iio: documentation: light: Add veml6030 sysfs documentation Date: Tue, 22 Oct 2019 18:41:27 +0530 Message-Id: <1571749887-9054-1-git-send-email-gupt21@gmail.com> X-Mailer: git-send-email 2.7.4 Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org The driver for veml6030 light sensor provides sysfs entries like configuring cutoff for interrupt. This commit document them. Signed-off-by: Rishi Gupta --- Changes in v5: * Use ABI/testing/sysfs-bus-iio to document sysfs files for veml6030 Changes in v4: * None Changes in v3: * Updated Date from September to October * Updated KernelVersion from 5.3.1 to 5.4 * in_illuminance_period_available is now in events directory Changes in v2: * None Documentation/ABI/testing/sysfs-bus-iio | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio index 6804516..a26d532 100644 --- a/Documentation/ABI/testing/sysfs-bus-iio +++ b/Documentation/ABI/testing/sysfs-bus-iio @@ -753,6 +753,8 @@ What: /sys/.../events/in_illuminance0_thresh_falling_value what: /sys/.../events/in_illuminance0_thresh_rising_value what: /sys/.../events/in_proximity0_thresh_falling_value what: /sys/.../events/in_proximity0_thresh_rising_value +What: /sys/.../events/in_illuminance_thresh_rising_value +What: /sys/.../events/in_illuminance_thresh_falling_value KernelVersion: 2.6.37 Contact: linux-iio@vger.kernel.org Description: @@ -972,6 +974,7 @@ What: /sys/.../events/in_activity_jogging_thresh_rising_period What: /sys/.../events/in_activity_jogging_thresh_falling_period What: /sys/.../events/in_activity_running_thresh_rising_period What: /sys/.../events/in_activity_running_thresh_falling_period +What: /sys/.../events/in_illuminance_thresh_either_period KernelVersion: 2.6.37 Contact: linux-iio@vger.kernel.org Description: @@ -1715,3 +1718,12 @@ Description: Mass concentration reading of particulate matter in ug / m3. pmX consists of particles with aerodynamic diameter less or equal to X micrometers. + +What: /sys/bus/iio/devices/iio:deviceX/events/in_illuminance_period_available +Date: October 2019 +KernelVersion: 5.4 +Contact: linux-iio@vger.kernel.org +Description: + List of valid values available in multiples of integration time + for which the light intensity must be above the threshold level + before interrupt is asserted. This refers to persistence values.