--- /dev/null
+/*
+ * Copyright (c) 2015 Intel Corporation
+ *
+ * Driver for UPISEMI us5182d Proximity and Ambient Light Sensor.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * To do: Interrupt support.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/mutex.h>
+
+#define US5182D_REG_CFG0 0x00
+#define US5182D_CFG0_ONESHOT_EN BIT(6)
+#define US5182D_CFG0_SHUTDOWN_EN BIT(7)
+#define US5182D_CFG0_WORD_ENABLE BIT(0)
+
+#define US5182D_REG_CFG1 0x01
+#define US5182D_CFG1_ALS_RES16 BIT(4)
+#define US5182D_CFG1_AGAIN_DEFAULT 0x00
+
+#define US5182D_REG_CFG2 0x02
+#define US5182D_CFG2_PX_RES16 BIT(4)
+#define US5182D_CFG2_PXGAIN_DEFAULT BIT(2)
+
+#define US5182D_REG_CFG3 0x03
+#define US5182D_CFG3_LED_CURRENT100 (BIT(4) | BIT(5))
+
+#define US5182D_REG_CFG4 0x10
+
+/*
+ * Registers for tuning the auto dark current cancelling feature.
+ * DARK_TH(reg 0x27,0x28) - threshold (counts) for auto dark cancelling.
+ * when ALS > DARK_TH --> ALS_Code = ALS - Upper(0x2A) * Dark
+ * when ALS < DARK_TH --> ALS_Code = ALS - Lower(0x29) * Dark
+ */
+#define US5182D_REG_UDARK_TH 0x27
+#define US5182D_REG_DARK_AUTO_EN 0x2b
+#define US5182D_REG_AUTO_LDARK_GAIN 0x29
+#define US5182D_REG_AUTO_HDARK_GAIN 0x2a
+
+#define US5182D_OPMODE_ALS 0x01
+#define US5182D_OPMODE_PX 0x02
+#define US5182D_OPMODE_SHIFT 4
+
+#define US5182D_REG_DARK_AUTO_EN_DEFAULT 0x80
+#define US5182D_REG_AUTO_LDARK_GAIN_DEFAULT 0x16
+#define US5182D_REG_AUTO_HDARK_GAIN_DEFAULT 0x00
+
+#define US5182D_REG_ADL 0x0c
+#define US5182D_REG_PDL 0x0e
+
+#define US5182D_REG_MODE_STORE 0x21
+#define US5182D_STORE_MODE 0x01
+
+#define US5182D_REG_CHIPID 0xb2
+
+#define US5182D_OPMODE_MASK GENMASK(5, 4)
+#define US5182D_AGAIN_MASK 0x07
+#define US5182D_RESET_CHIP 0x01
+
+#define US5182D_CHIPID 0x26
+#define US5182D_DRV_NAME "us5182d"
+
+#define US5182D_GA_RESOLUTION 1000
+
+#define US5182D_READ_BYTE 1
+#define US5182D_READ_WORD 2
+#define US5182D_OPSTORE_SLEEP_TIME 20 /* ms */
+
+/* Available ranges: [12354, 7065, 3998, 2202, 1285, 498, 256, 138] lux */
+static const int us5182d_scales[] = {188500, 107800, 61000, 33600, 19600, 7600,
+ 3900, 2100};
+
+/*
+ * Experimental thresholds that work with US5182D sensor on evaluation board
+ * roughly between 12-32 lux
+ */
+static u16 us5182d_dark_ths_vals[] = {170, 200, 512, 512, 800, 2000, 4000,
+ 8000};
+
+enum mode {
+ US5182D_ALS_PX,
+ US5182D_ALS_ONLY,
+ US5182D_PX_ONLY
+};
+
+struct us5182d_data {
+ struct i2c_client *client;
+ struct mutex lock;
+
+ /* Glass attenuation factor */
+ u32 ga;
+
+ /* Dark gain tuning */
+ u8 lower_dark_gain;
+ u8 upper_dark_gain;
+ u16 *us5182d_dark_ths;
+
+ u8 opmode;
+};
+
+static IIO_CONST_ATTR(in_illuminance_scale_available,
+ "0.0021 0.0039 0.0076 0.0196 0.0336 0.061 0.1078 0.1885");
+
+static struct attribute *us5182d_attrs[] = {
+ &iio_const_attr_in_illuminance_scale_available.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group us5182d_attr_group = {
+ .attrs = us5182d_attrs,
+};
+
+static const struct {
+ u8 reg;
+ u8 val;
+} us5182d_regvals[] = {
+ {US5182D_REG_CFG0, (US5182D_CFG0_SHUTDOWN_EN |
+ US5182D_CFG0_WORD_ENABLE)},
+ {US5182D_REG_CFG1, US5182D_CFG1_ALS_RES16},
+ {US5182D_REG_CFG2, (US5182D_CFG2_PX_RES16 |
+ US5182D_CFG2_PXGAIN_DEFAULT)},
+ {US5182D_REG_CFG3, US5182D_CFG3_LED_CURRENT100},
+ {US5182D_REG_MODE_STORE, US5182D_STORE_MODE},
+ {US5182D_REG_CFG4, 0x00},
+};
+
+static const struct iio_chan_spec us5182d_channels[] = {
+ {
+ .type = IIO_LIGHT,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ },
+ {
+ .type = IIO_PROXIMITY,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ }
+};
+
+static int us5182d_get_als(struct us5182d_data *data)
+{
+ int ret;
+ unsigned long result;
+
+ ret = i2c_smbus_read_word_data(data->client,
+ US5182D_REG_ADL);
+ if (ret < 0)
+ return ret;
+
+ result = ret * data->ga / US5182D_GA_RESOLUTION;
+ if (result > 0xffff)
+ result = 0xffff;
+
+ return result;
+}
+
+static int us5182d_set_opmode(struct us5182d_data *data, u8 mode)
+{
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG0);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * In oneshot mode the chip will power itself down after taking the
+ * required measurement.
+ */
+ ret = ret | US5182D_CFG0_ONESHOT_EN;
+
+ /* update mode */
+ ret = ret & ~US5182D_OPMODE_MASK;
+ ret = ret | (mode << US5182D_OPMODE_SHIFT);
+
+ /*
+ * After updating the operating mode, the chip requires that
+ * the operation is stored, by writing 1 in the STORE_MODE
+ * register (auto-clearing).
+ */
+ ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG0, ret);
+ if (ret < 0)
+ return ret;
+
+ if (mode == data->opmode)
+ return 0;
+
+ ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_MODE_STORE,
+ US5182D_STORE_MODE);
+ if (ret < 0)
+ return ret;
+
+ data->opmode = mode;
+ msleep(US5182D_OPSTORE_SLEEP_TIME);
+
+ return 0;
+}
+
+static int us5182d_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val,
+ int *val2, long mask)
+{
+ struct us5182d_data *data = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ switch (chan->type) {
+ case IIO_LIGHT:
+ mutex_lock(&data->lock);
+ ret = us5182d_set_opmode(data, US5182D_OPMODE_ALS);
+ if (ret < 0)
+ goto out_err;
+
+ ret = us5182d_get_als(data);
+ if (ret < 0)
+ goto out_err;
+ mutex_unlock(&data->lock);
+ *val = ret;
+ return IIO_VAL_INT;
+ case IIO_PROXIMITY:
+ mutex_lock(&data->lock);
+ ret = us5182d_set_opmode(data, US5182D_OPMODE_PX);
+ if (ret < 0)
+ goto out_err;
+
+ ret = i2c_smbus_read_word_data(data->client,
+ US5182D_REG_PDL);
+ if (ret < 0)
+ goto out_err;
+ mutex_unlock(&data->lock);
+ *val = ret;
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+
+ case IIO_CHAN_INFO_SCALE:
+ ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG1);
+ if (ret < 0)
+ return ret;
+
+ *val = 0;
+ *val2 = us5182d_scales[ret & US5182D_AGAIN_MASK];
+
+ return IIO_VAL_INT_PLUS_MICRO;
+ default:
+ return -EINVAL;
+ }
+
+ return -EINVAL;
+out_err:
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+/**
+ * us5182d_update_dark_th - update Darh_Th registers
+ * @data us5182d_data structure
+ * @index index in us5182d_dark_ths array to use for the updated value
+ *
+ * Function needs to be called with a lock held because it needs two i2c write
+ * byte operations as these registers (0x27 0x28) don't work in word mode
+ * accessing.
+ */
+static int us5182d_update_dark_th(struct us5182d_data *data, int index)
+{
+ __be16 dark_th = cpu_to_be16(data->us5182d_dark_ths[index]);
+ int ret;
+
+ ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_UDARK_TH,
+ ((u8 *)&dark_th)[0]);
+ if (ret < 0)
+ return ret;
+
+ return i2c_smbus_write_byte_data(data->client, US5182D_REG_UDARK_TH + 1,
+ ((u8 *)&dark_th)[1]);
+}
+
+/**
+ * us5182d_apply_scale - update the ALS scale
+ * @data us5182d_data structure
+ * @index index in us5182d_scales array to use for the updated value
+ *
+ * Function needs to be called with a lock held as we're having more than one
+ * i2c operation.
+ */
+static int us5182d_apply_scale(struct us5182d_data *data, int index)
+{
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG1);
+ if (ret < 0)
+ return ret;
+
+ ret = ret & (~US5182D_AGAIN_MASK);
+ ret |= index;
+
+ ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG1, ret);
+ if (ret < 0)
+ return ret;
+
+ return us5182d_update_dark_th(data, index);
+}
+
+static int us5182d_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int val,
+ int val2, long mask)
+{
+ struct us5182d_data *data = iio_priv(indio_dev);
+ int ret, i;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ if (val != 0)
+ return -EINVAL;
+ for (i = 0; i < ARRAY_SIZE(us5182d_scales); i++)
+ if (val2 == us5182d_scales[i]) {
+ mutex_lock(&data->lock);
+ ret = us5182d_apply_scale(data, i);
+ mutex_unlock(&data->lock);
+ return ret;
+ }
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return -EINVAL;
+}
+
+static const struct iio_info us5182d_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = us5182d_read_raw,
+ .write_raw = us5182d_write_raw,
+ .attrs = &us5182d_attr_group,
+};
+
+static int us5182d_reset(struct iio_dev *indio_dev)
+{
+ struct us5182d_data *data = iio_priv(indio_dev);
+
+ return i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG3,
+ US5182D_RESET_CHIP);
+}
+
+static int us5182d_init(struct iio_dev *indio_dev)
+{
+ struct us5182d_data *data = iio_priv(indio_dev);
+ int i, ret;
+
+ ret = us5182d_reset(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ data->opmode = 0;
+ for (i = 0; i < ARRAY_SIZE(us5182d_regvals); i++) {
+ ret = i2c_smbus_write_byte_data(data->client,
+ us5182d_regvals[i].reg,
+ us5182d_regvals[i].val);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
+}
+
+static void us5182d_get_platform_data(struct iio_dev *indio_dev)
+{
+ struct us5182d_data *data = iio_priv(indio_dev);
+
+ if (device_property_read_u32(&data->client->dev, "upisemi,glass-coef",
+ &data->ga))
+ data->ga = US5182D_GA_RESOLUTION;
+ if (device_property_read_u16_array(&data->client->dev,
+ "upisemi,dark-ths",
+ data->us5182d_dark_ths,
+ ARRAY_SIZE(us5182d_dark_ths_vals)))
+ data->us5182d_dark_ths = us5182d_dark_ths_vals;
+ if (device_property_read_u8(&data->client->dev,
+ "upisemi,upper-dark-gain",
+ &data->upper_dark_gain))
+ data->upper_dark_gain = US5182D_REG_AUTO_HDARK_GAIN_DEFAULT;
+ if (device_property_read_u8(&data->client->dev,
+ "upisemi,lower-dark-gain",
+ &data->lower_dark_gain))
+ data->lower_dark_gain = US5182D_REG_AUTO_LDARK_GAIN_DEFAULT;
+}
+
+static int us5182d_dark_gain_config(struct iio_dev *indio_dev)
+{
+ struct us5182d_data *data = iio_priv(indio_dev);
+ int ret;
+
+ ret = us5182d_update_dark_th(data, US5182D_CFG1_AGAIN_DEFAULT);
+ if (ret < 0)
+ return ret;
+
+ ret = i2c_smbus_write_byte_data(data->client,
+ US5182D_REG_AUTO_LDARK_GAIN,
+ data->lower_dark_gain);
+ if (ret < 0)
+ return ret;
+
+ ret = i2c_smbus_write_byte_data(data->client,
+ US5182D_REG_AUTO_HDARK_GAIN,
+ data->upper_dark_gain);
+ if (ret < 0)
+ return ret;
+
+ return i2c_smbus_write_byte_data(data->client, US5182D_REG_DARK_AUTO_EN,
+ US5182D_REG_DARK_AUTO_EN_DEFAULT);
+}
+
+static int us5182d_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct us5182d_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->lock);
+
+ indio_dev->dev.parent = &client->dev;
+ indio_dev->info = &us5182d_info;
+ indio_dev->name = US5182D_DRV_NAME;
+ indio_dev->channels = us5182d_channels;
+ indio_dev->num_channels = ARRAY_SIZE(us5182d_channels);
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CHIPID);
+ if (ret != US5182D_CHIPID) {
+ dev_err(&data->client->dev,
+ "Failed to detect US5182 light chip\n");
+ return (ret < 0) ? ret : -ENODEV;
+ }
+
+ us5182d_get_platform_data(indio_dev);
+ ret = us5182d_init(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ ret = us5182d_dark_gain_config(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ return iio_device_register(indio_dev);
+}
+
+static int us5182d_remove(struct i2c_client *client)
+{
+ iio_device_unregister(i2c_get_clientdata(client));
+ return i2c_smbus_write_byte_data(client, US5182D_REG_CFG0,
+ US5182D_CFG0_SHUTDOWN_EN);
+}
+
+static const struct acpi_device_id us5182d_acpi_match[] = {
+ { "USD5182", 0},
+ {}
+};
+
+MODULE_DEVICE_TABLE(acpi, us5182d_acpi_match);
+
+static const struct i2c_device_id us5182d_id[] = {
+ {"usd5182", 0},
+ {}
+};
+
+MODULE_DEVICE_TABLE(i2c, us5182d_id);
+
+static struct i2c_driver us5182d_driver = {
+ .driver = {
+ .name = US5182D_DRV_NAME,
+ .acpi_match_table = ACPI_PTR(us5182d_acpi_match),
+ },
+ .probe = us5182d_probe,
+ .remove = us5182d_remove,
+ .id_table = us5182d_id,
+
+};
+module_i2c_driver(us5182d_driver);
+
+MODULE_AUTHOR("Adriana Reus <adriana.reus@intel.com>");
+MODULE_DESCRIPTION("Driver for us5182d Proximity and Light Sensor");
+MODULE_LICENSE("GPL v2");
projects / linux-beck.git / commitdiff