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Diffstat (limited to 'drivers/iio/light/cm32181.c')
-rw-r--r--drivers/iio/light/cm32181.c552
1 files changed, 552 insertions, 0 deletions
diff --git a/drivers/iio/light/cm32181.c b/drivers/iio/light/cm32181.c
new file mode 100644
index 0000000000..9df85b3999
--- /dev/null
+++ b/drivers/iio/light/cm32181.c
@@ -0,0 +1,552 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2013 Capella Microsystems Inc.
+ * Author: Kevin Tsai <ktsai@capellamicro.com>
+ */
+
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/mutex.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/interrupt.h>
+#include <linux/regulator/consumer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/events.h>
+#include <linux/init.h>
+
+/* Registers Address */
+#define CM32181_REG_ADDR_CMD 0x00
+#define CM32181_REG_ADDR_WH 0x01
+#define CM32181_REG_ADDR_WL 0x02
+#define CM32181_REG_ADDR_TEST 0x03
+#define CM32181_REG_ADDR_ALS 0x04
+#define CM32181_REG_ADDR_STATUS 0x06
+#define CM32181_REG_ADDR_ID 0x07
+
+/* Number of Configurable Registers */
+#define CM32181_CONF_REG_NUM 4
+
+/* CMD register */
+#define CM32181_CMD_ALS_DISABLE BIT(0)
+#define CM32181_CMD_ALS_INT_EN BIT(1)
+#define CM32181_CMD_ALS_THRES_WINDOW BIT(2)
+
+#define CM32181_CMD_ALS_PERS_SHIFT 4
+#define CM32181_CMD_ALS_PERS_MASK (0x03 << CM32181_CMD_ALS_PERS_SHIFT)
+#define CM32181_CMD_ALS_PERS_DEFAULT (0x01 << CM32181_CMD_ALS_PERS_SHIFT)
+
+#define CM32181_CMD_ALS_IT_SHIFT 6
+#define CM32181_CMD_ALS_IT_MASK (0x0F << CM32181_CMD_ALS_IT_SHIFT)
+#define CM32181_CMD_ALS_IT_DEFAULT (0x00 << CM32181_CMD_ALS_IT_SHIFT)
+
+#define CM32181_CMD_ALS_SM_SHIFT 11
+#define CM32181_CMD_ALS_SM_MASK (0x03 << CM32181_CMD_ALS_SM_SHIFT)
+#define CM32181_CMD_ALS_SM_DEFAULT (0x01 << CM32181_CMD_ALS_SM_SHIFT)
+
+#define CM32181_LUX_PER_BIT 500 /* ALS_SM=01 IT=800ms */
+#define CM32181_LUX_PER_BIT_RESOLUTION 100000
+#define CM32181_LUX_PER_BIT_BASE_IT 800000 /* Based on IT=800ms */
+#define CM32181_CALIBSCALE_DEFAULT 100000
+#define CM32181_CALIBSCALE_RESOLUTION 100000
+
+#define SMBUS_ALERT_RESPONSE_ADDRESS 0x0c
+
+/* CPM0 Index 0: device-id (3218 or 32181), 1: Unknown, 2: init_regs_bitmap */
+#define CPM0_REGS_BITMAP 2
+#define CPM0_HEADER_SIZE 3
+
+/* CPM1 Index 0: lux_per_bit, 1: calibscale, 2: resolution (100000) */
+#define CPM1_LUX_PER_BIT 0
+#define CPM1_CALIBSCALE 1
+#define CPM1_SIZE 3
+
+/* CM3218 Family */
+static const int cm3218_als_it_bits[] = { 0, 1, 2, 3 };
+static const int cm3218_als_it_values[] = { 100000, 200000, 400000, 800000 };
+
+/* CM32181 Family */
+static const int cm32181_als_it_bits[] = { 12, 8, 0, 1, 2, 3 };
+static const int cm32181_als_it_values[] = {
+ 25000, 50000, 100000, 200000, 400000, 800000
+};
+
+struct cm32181_chip {
+ struct i2c_client *client;
+ struct device *dev;
+ struct mutex lock;
+ u16 conf_regs[CM32181_CONF_REG_NUM];
+ unsigned long init_regs_bitmap;
+ int calibscale;
+ int lux_per_bit;
+ int lux_per_bit_base_it;
+ int num_als_it;
+ const int *als_it_bits;
+ const int *als_it_values;
+};
+
+static int cm32181_read_als_it(struct cm32181_chip *cm32181, int *val2);
+
+#ifdef CONFIG_ACPI
+/**
+ * cm32181_acpi_get_cpm() - Get CPM object from ACPI
+ * @dev: pointer of struct device.
+ * @obj_name: pointer of ACPI object name.
+ * @values: pointer of array for return elements.
+ * @count: maximum size of return array.
+ *
+ * Convert ACPI CPM table to array.
+ *
+ * Return: -ENODEV for fail. Otherwise is number of elements.
+ */
+static int cm32181_acpi_get_cpm(struct device *dev, char *obj_name,
+ u64 *values, int count)
+{
+ struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+ union acpi_object *cpm, *elem;
+ acpi_handle handle;
+ acpi_status status;
+ int i;
+
+ handle = ACPI_HANDLE(dev);
+ if (!handle)
+ return -ENODEV;
+
+ status = acpi_evaluate_object(handle, obj_name, NULL, &buffer);
+ if (ACPI_FAILURE(status)) {
+ dev_err(dev, "object %s not found\n", obj_name);
+ return -ENODEV;
+ }
+
+ cpm = buffer.pointer;
+ if (cpm->package.count > count)
+ dev_warn(dev, "%s table contains %u values, only using first %d values\n",
+ obj_name, cpm->package.count, count);
+
+ count = min_t(int, cpm->package.count, count);
+ for (i = 0; i < count; i++) {
+ elem = &(cpm->package.elements[i]);
+ values[i] = elem->integer.value;
+ }
+
+ kfree(buffer.pointer);
+
+ return count;
+}
+
+static void cm32181_acpi_parse_cpm_tables(struct cm32181_chip *cm32181)
+{
+ u64 vals[CPM0_HEADER_SIZE + CM32181_CONF_REG_NUM];
+ struct device *dev = cm32181->dev;
+ int i, count;
+
+ count = cm32181_acpi_get_cpm(dev, "CPM0", vals, ARRAY_SIZE(vals));
+ if (count <= CPM0_HEADER_SIZE)
+ return;
+
+ count -= CPM0_HEADER_SIZE;
+
+ cm32181->init_regs_bitmap = vals[CPM0_REGS_BITMAP];
+ cm32181->init_regs_bitmap &= GENMASK(count - 1, 0);
+ for_each_set_bit(i, &cm32181->init_regs_bitmap, count)
+ cm32181->conf_regs[i] = vals[CPM0_HEADER_SIZE + i];
+
+ count = cm32181_acpi_get_cpm(dev, "CPM1", vals, ARRAY_SIZE(vals));
+ if (count != CPM1_SIZE)
+ return;
+
+ cm32181->lux_per_bit = vals[CPM1_LUX_PER_BIT];
+
+ /* Check for uncalibrated devices */
+ if (vals[CPM1_CALIBSCALE] == CM32181_CALIBSCALE_DEFAULT)
+ return;
+
+ cm32181->calibscale = vals[CPM1_CALIBSCALE];
+ /* CPM1 lux_per_bit is for the current it value */
+ cm32181_read_als_it(cm32181, &cm32181->lux_per_bit_base_it);
+}
+#else
+static void cm32181_acpi_parse_cpm_tables(struct cm32181_chip *cm32181)
+{
+}
+#endif /* CONFIG_ACPI */
+
+/**
+ * cm32181_reg_init() - Initialize CM32181 registers
+ * @cm32181: pointer of struct cm32181.
+ *
+ * Initialize CM32181 ambient light sensor register to default values.
+ *
+ * Return: 0 for success; otherwise for error code.
+ */
+static int cm32181_reg_init(struct cm32181_chip *cm32181)
+{
+ struct i2c_client *client = cm32181->client;
+ int i;
+ s32 ret;
+
+ ret = i2c_smbus_read_word_data(client, CM32181_REG_ADDR_ID);
+ if (ret < 0)
+ return ret;
+
+ /* check device ID */
+ switch (ret & 0xFF) {
+ case 0x18: /* CM3218 */
+ cm32181->num_als_it = ARRAY_SIZE(cm3218_als_it_bits);
+ cm32181->als_it_bits = cm3218_als_it_bits;
+ cm32181->als_it_values = cm3218_als_it_values;
+ break;
+ case 0x81: /* CM32181 */
+ case 0x82: /* CM32182, fully compat. with CM32181 */
+ cm32181->num_als_it = ARRAY_SIZE(cm32181_als_it_bits);
+ cm32181->als_it_bits = cm32181_als_it_bits;
+ cm32181->als_it_values = cm32181_als_it_values;
+ break;
+ default:
+ return -ENODEV;
+ }
+
+ /* Default Values */
+ cm32181->conf_regs[CM32181_REG_ADDR_CMD] =
+ CM32181_CMD_ALS_IT_DEFAULT | CM32181_CMD_ALS_SM_DEFAULT;
+ cm32181->init_regs_bitmap = BIT(CM32181_REG_ADDR_CMD);
+ cm32181->calibscale = CM32181_CALIBSCALE_DEFAULT;
+ cm32181->lux_per_bit = CM32181_LUX_PER_BIT;
+ cm32181->lux_per_bit_base_it = CM32181_LUX_PER_BIT_BASE_IT;
+
+ if (ACPI_HANDLE(cm32181->dev))
+ cm32181_acpi_parse_cpm_tables(cm32181);
+
+ /* Initialize registers*/
+ for_each_set_bit(i, &cm32181->init_regs_bitmap, CM32181_CONF_REG_NUM) {
+ ret = i2c_smbus_write_word_data(client, i,
+ cm32181->conf_regs[i]);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
+}
+
+/**
+ * cm32181_read_als_it() - Get sensor integration time (ms)
+ * @cm32181: pointer of struct cm32181
+ * @val2: pointer of int to load the als_it value.
+ *
+ * Report the current integration time in milliseconds.
+ *
+ * Return: IIO_VAL_INT_PLUS_MICRO for success, otherwise -EINVAL.
+ */
+static int cm32181_read_als_it(struct cm32181_chip *cm32181, int *val2)
+{
+ u16 als_it;
+ int i;
+
+ als_it = cm32181->conf_regs[CM32181_REG_ADDR_CMD];
+ als_it &= CM32181_CMD_ALS_IT_MASK;
+ als_it >>= CM32181_CMD_ALS_IT_SHIFT;
+ for (i = 0; i < cm32181->num_als_it; i++) {
+ if (als_it == cm32181->als_it_bits[i]) {
+ *val2 = cm32181->als_it_values[i];
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+ }
+
+ return -EINVAL;
+}
+
+/**
+ * cm32181_write_als_it() - Write sensor integration time
+ * @cm32181: pointer of struct cm32181.
+ * @val: integration time by millisecond.
+ *
+ * Convert integration time (ms) to sensor value.
+ *
+ * Return: i2c_smbus_write_word_data command return value.
+ */
+static int cm32181_write_als_it(struct cm32181_chip *cm32181, int val)
+{
+ struct i2c_client *client = cm32181->client;
+ u16 als_it;
+ int ret, i, n;
+
+ n = cm32181->num_als_it;
+ for (i = 0; i < n; i++)
+ if (val <= cm32181->als_it_values[i])
+ break;
+ if (i >= n)
+ i = n - 1;
+
+ als_it = cm32181->als_it_bits[i];
+ als_it <<= CM32181_CMD_ALS_IT_SHIFT;
+
+ mutex_lock(&cm32181->lock);
+ cm32181->conf_regs[CM32181_REG_ADDR_CMD] &=
+ ~CM32181_CMD_ALS_IT_MASK;
+ cm32181->conf_regs[CM32181_REG_ADDR_CMD] |=
+ als_it;
+ ret = i2c_smbus_write_word_data(client, CM32181_REG_ADDR_CMD,
+ cm32181->conf_regs[CM32181_REG_ADDR_CMD]);
+ mutex_unlock(&cm32181->lock);
+
+ return ret;
+}
+
+/**
+ * cm32181_get_lux() - report current lux value
+ * @cm32181: pointer of struct cm32181.
+ *
+ * Convert sensor raw data to lux. It depends on integration
+ * time and calibscale variable.
+ *
+ * Return: Positive value is lux, otherwise is error code.
+ */
+static int cm32181_get_lux(struct cm32181_chip *cm32181)
+{
+ struct i2c_client *client = cm32181->client;
+ int ret;
+ int als_it;
+ u64 lux;
+
+ ret = cm32181_read_als_it(cm32181, &als_it);
+ if (ret < 0)
+ return -EINVAL;
+
+ lux = cm32181->lux_per_bit;
+ lux *= cm32181->lux_per_bit_base_it;
+ lux = div_u64(lux, als_it);
+
+ ret = i2c_smbus_read_word_data(client, CM32181_REG_ADDR_ALS);
+ if (ret < 0)
+ return ret;
+
+ lux *= ret;
+ lux *= cm32181->calibscale;
+ lux = div_u64(lux, CM32181_CALIBSCALE_RESOLUTION);
+ lux = div_u64(lux, CM32181_LUX_PER_BIT_RESOLUTION);
+
+ if (lux > 0xFFFF)
+ lux = 0xFFFF;
+
+ return lux;
+}
+
+static int cm32181_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct cm32181_chip *cm32181 = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_PROCESSED:
+ ret = cm32181_get_lux(cm32181);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_CALIBSCALE:
+ *val = cm32181->calibscale;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_INT_TIME:
+ *val = 0;
+ ret = cm32181_read_als_it(cm32181, val2);
+ return ret;
+ }
+
+ return -EINVAL;
+}
+
+static int cm32181_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct cm32181_chip *cm32181 = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_CALIBSCALE:
+ cm32181->calibscale = val;
+ return val;
+ case IIO_CHAN_INFO_INT_TIME:
+ ret = cm32181_write_als_it(cm32181, val2);
+ return ret;
+ }
+
+ return -EINVAL;
+}
+
+/**
+ * cm32181_get_it_available() - Get available ALS IT value
+ * @dev: pointer of struct device.
+ * @attr: pointer of struct device_attribute.
+ * @buf: pointer of return string buffer.
+ *
+ * Display the available integration time values by millisecond.
+ *
+ * Return: string length.
+ */
+static ssize_t cm32181_get_it_available(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct cm32181_chip *cm32181 = iio_priv(dev_to_iio_dev(dev));
+ int i, n, len;
+
+ n = cm32181->num_als_it;
+ for (i = 0, len = 0; i < n; i++)
+ len += sprintf(buf + len, "0.%06u ", cm32181->als_it_values[i]);
+ return len + sprintf(buf + len, "\n");
+}
+
+static const struct iio_chan_spec cm32181_channels[] = {
+ {
+ .type = IIO_LIGHT,
+ .info_mask_separate =
+ BIT(IIO_CHAN_INFO_PROCESSED) |
+ BIT(IIO_CHAN_INFO_CALIBSCALE) |
+ BIT(IIO_CHAN_INFO_INT_TIME),
+ }
+};
+
+static IIO_DEVICE_ATTR(in_illuminance_integration_time_available,
+ S_IRUGO, cm32181_get_it_available, NULL, 0);
+
+static struct attribute *cm32181_attributes[] = {
+ &iio_dev_attr_in_illuminance_integration_time_available.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group cm32181_attribute_group = {
+ .attrs = cm32181_attributes
+};
+
+static const struct iio_info cm32181_info = {
+ .read_raw = &cm32181_read_raw,
+ .write_raw = &cm32181_write_raw,
+ .attrs = &cm32181_attribute_group,
+};
+
+static void cm32181_unregister_dummy_client(void *data)
+{
+ struct i2c_client *client = data;
+
+ /* Unregister the dummy client */
+ i2c_unregister_device(client);
+}
+
+static int cm32181_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct cm32181_chip *cm32181;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*cm32181));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ i2c_set_clientdata(client, indio_dev);
+
+ /*
+ * Some ACPI systems list 2 I2C resources for the CM3218 sensor, the
+ * SMBus Alert Response Address (ARA, 0x0c) and the actual I2C address.
+ * Detect this and take the following step to deal with it:
+ * 1. When a SMBus Alert capable sensor has an Alert asserted, it will
+ * not respond on its actual I2C address. Read a byte from the ARA
+ * to clear any pending Alerts.
+ * 2. Create a "dummy" client for the actual I2C address and
+ * use that client to communicate with the sensor.
+ */
+ if (ACPI_HANDLE(dev) && client->addr == SMBUS_ALERT_RESPONSE_ADDRESS) {
+ struct i2c_board_info board_info = { .type = "dummy" };
+
+ i2c_smbus_read_byte(client);
+
+ client = i2c_acpi_new_device(dev, 1, &board_info);
+ if (IS_ERR(client))
+ return PTR_ERR(client);
+
+ ret = devm_add_action_or_reset(dev, cm32181_unregister_dummy_client, client);
+ if (ret)
+ return ret;
+ }
+
+ cm32181 = iio_priv(indio_dev);
+ cm32181->client = client;
+ cm32181->dev = dev;
+
+ mutex_init(&cm32181->lock);
+ indio_dev->channels = cm32181_channels;
+ indio_dev->num_channels = ARRAY_SIZE(cm32181_channels);
+ indio_dev->info = &cm32181_info;
+ indio_dev->name = dev_name(dev);
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = cm32181_reg_init(cm32181);
+ if (ret) {
+ dev_err(dev, "%s: register init failed\n", __func__);
+ return ret;
+ }
+
+ ret = devm_iio_device_register(dev, indio_dev);
+ if (ret) {
+ dev_err(dev, "%s: regist device failed\n", __func__);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int cm32181_suspend(struct device *dev)
+{
+ struct cm32181_chip *cm32181 = iio_priv(dev_get_drvdata(dev));
+ struct i2c_client *client = cm32181->client;
+
+ return i2c_smbus_write_word_data(client, CM32181_REG_ADDR_CMD,
+ CM32181_CMD_ALS_DISABLE);
+}
+
+static int cm32181_resume(struct device *dev)
+{
+ struct cm32181_chip *cm32181 = iio_priv(dev_get_drvdata(dev));
+ struct i2c_client *client = cm32181->client;
+
+ return i2c_smbus_write_word_data(client, CM32181_REG_ADDR_CMD,
+ cm32181->conf_regs[CM32181_REG_ADDR_CMD]);
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(cm32181_pm_ops, cm32181_suspend, cm32181_resume);
+
+static const struct of_device_id cm32181_of_match[] = {
+ { .compatible = "capella,cm3218" },
+ { .compatible = "capella,cm32181" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, cm32181_of_match);
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id cm32181_acpi_match[] = {
+ { "CPLM3218", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, cm32181_acpi_match);
+#endif
+
+static struct i2c_driver cm32181_driver = {
+ .driver = {
+ .name = "cm32181",
+ .acpi_match_table = ACPI_PTR(cm32181_acpi_match),
+ .of_match_table = cm32181_of_match,
+ .pm = pm_sleep_ptr(&cm32181_pm_ops),
+ },
+ .probe = cm32181_probe,
+};
+
+module_i2c_driver(cm32181_driver);
+
+MODULE_AUTHOR("Kevin Tsai <ktsai@capellamicro.com>");
+MODULE_DESCRIPTION("CM32181 ambient light sensor driver");
+MODULE_LICENSE("GPL");