2015-06-10 14:20:08

by Daniel Baluta

[permalink] [raw]
Subject: [PATCH v3] iio: light: Add support for ROHM RPR0521 sensor

This patch adds support for ROHM RPR0521 ambient light and proximity
sensor. It offers raw readings for intensity and proximity.

Signed-off-by: Daniel Baluta <[email protected]>
---
Changes since v2: (after Peter's review)
* replaced calibscale with scale
* several style fixes (new lines, spellings, etc)
* fixed proximity interpretation. Now we have the
following relation: high proximity <-> low distance
* will send a follow up patch to clarify the ABI description
and to fix all other drivers that misinterpret this.

drivers/iio/light/Kconfig | 11 +
drivers/iio/light/Makefile | 1 +
drivers/iio/light/rpr0521.c | 622 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 634 insertions(+)
create mode 100644 drivers/iio/light/rpr0521.c

diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index e6198b7..cbc4677 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -168,6 +168,17 @@ config JSA1212
To compile this driver as a module, choose M here:
the module will be called jsa1212.

+config RPR0521
+ tristate "ROHM RPR0521 ALS and proximity sensor driver"
+ depends on I2C
+ select REGMAP_I2C
+ help
+ Say Y here if you want to build support for ROHM's RPR0521
+ ambient light and proximity sensor device.
+
+ To compile this driver as a module, choose M here:
+ the module will be called rpr0521.
+
config SENSORS_LM3533
tristate "LM3533 ambient light sensor"
depends on MFD_LM3533
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index e2d50fd..adf9723 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_ISL29125) += isl29125.o
obj-$(CONFIG_JSA1212) += jsa1212.o
obj-$(CONFIG_SENSORS_LM3533) += lm3533-als.o
obj-$(CONFIG_LTR501) += ltr501.o
+obj-$(CONFIG_RPR0521) += rpr0521.o
obj-$(CONFIG_SENSORS_TSL2563) += tsl2563.o
obj-$(CONFIG_STK3310) += stk3310.o
obj-$(CONFIG_TCS3414) += tcs3414.o
diff --git a/drivers/iio/light/rpr0521.c b/drivers/iio/light/rpr0521.c
new file mode 100644
index 0000000..a75032ea
--- /dev/null
+++ b/drivers/iio/light/rpr0521.c
@@ -0,0 +1,622 @@
+/*
+ * RPR-0521 ROHM Ambient Light and Proximity Sensor
+ *
+ * Copyright (c) 2015, Intel Corporation.
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License. See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * IIO driver for RPR-0521RS (7-bit I2C slave address 0x38).
+ *
+ * TODO: illuminance channel, PM support, buffer
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/delay.h>
+#include <linux/acpi.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/pm_runtime.h>
+
+#define RPR0521_REG_SYSTEM_CTRL 0x40
+#define RPR0521_REG_MODE_CTRL 0x41
+#define RPR0521_REG_ALS_CTRL 0x42
+#define RPR0521_REG_PXS_CTRL 0x43
+#define RPR0521_REG_PXS_DATA 0x44 /* 16-bit, little endian */
+#define RPR0521_REG_ALS_DATA0 0x46 /* 16-bit, little endian */
+#define RPR0521_REG_ALS_DATA1 0x48 /* 16-bit, little endian */
+#define RPR0521_REG_ID 0x92
+
+#define RPR0521_MODE_ALS_MASK BIT(7)
+#define RPR0521_MODE_PXS_MASK BIT(6)
+#define RPR0521_MODE_MEAS_TIME_MASK GENMASK(3, 0)
+#define RPR0521_ALS_DATA0_GAIN_MASK (BIT(4) | BIT(5))
+#define RPR0521_ALS_DATA0_GAIN_SHIFT 4
+#define RPR0521_ALS_DATA1_GAIN_MASK (BIT(2) | BIT(3))
+#define RPR0521_ALS_DATA1_GAIN_SHIFT 2
+#define RPR0521_PXS_GAIN_MASK (BIT(4) | BIT(5))
+#define RPR0521_PXS_GAIN_SHIFT 4
+
+#define RPR0521_MODE_ALS_ENABLE BIT(7)
+#define RPR0521_MODE_ALS_DISABLE 0x00
+#define RPR0521_MODE_PXS_ENABLE BIT(6)
+#define RPR0521_MODE_PXS_DISABLE 0x00
+
+#define RPR0521_PXS_MAX_VAL (BIT(13) - 1)
+#define RPR0521_MANUFACT_ID 0xE0
+#define RPR0521_DEFAULT_MEAS_TIME 0x06 /* ALS - 100ms, PXS - 100ms */
+
+#define RPR0521_DRV_NAME "RPR0521"
+#define RPR0521_REGMAP_NAME "rpr0521_regmap"
+
+#define RPR0521_SLEEP_DELAY_MS 2000
+
+#define RPR0521_ALS_SCALE_AVAIL "0.007812 0.015625 0.5 1"
+#define RPR0521_PXS_SCALE_AVAIL "0.125 0.5 1"
+
+struct rpr0521_gain {
+ int scale;
+ int uscale;
+};
+
+static const struct rpr0521_gain rpr0521_als_gain[4] = {
+ {1, 0}, /* x1 */
+ {0, 500000}, /* x2 */
+ {0, 15625}, /* x64 */
+ {0, 7812}, /* x128 */
+};
+
+static const struct rpr0521_gain rpr0521_pxs_gain[3] = {
+ {1, 0}, /* x1 */
+ {0, 500000}, /* x2 */
+ {0, 125000}, /* x4 */
+};
+
+enum rpr0521_channel {
+ RPR0521_CHAN_ALS_DATA0,
+ RPR0521_CHAN_ALS_DATA1,
+ RPR0521_CHAN_PXS,
+};
+
+struct rpr0521_reg_desc {
+ u8 address;
+ u8 device_mask;
+};
+
+static const struct rpr0521_reg_desc rpr0521_data_reg[] = {
+ [RPR0521_CHAN_ALS_DATA0] = {
+ .address = RPR0521_REG_ALS_DATA0,
+ .device_mask = RPR0521_MODE_ALS_MASK,
+ },
+ [RPR0521_CHAN_ALS_DATA1] = {
+ .address = RPR0521_REG_ALS_DATA1,
+ .device_mask = RPR0521_MODE_ALS_MASK,
+ },
+ [RPR0521_CHAN_PXS] = {
+ .address = RPR0521_REG_PXS_DATA,
+ .device_mask = RPR0521_MODE_PXS_MASK,
+ },
+};
+
+static const struct rpr0521_gain_info {
+ u8 reg;
+ u8 mask;
+ u8 shift;
+ const struct rpr0521_gain *gain;
+ int size;
+} rpr0521_gain[] = {
+ [RPR0521_CHAN_ALS_DATA0] = {
+ .reg = RPR0521_REG_ALS_CTRL,
+ .mask = RPR0521_ALS_DATA0_GAIN_MASK,
+ .shift = RPR0521_ALS_DATA0_GAIN_SHIFT,
+ .gain = rpr0521_als_gain,
+ .size = ARRAY_SIZE(rpr0521_als_gain),
+ },
+ [RPR0521_CHAN_ALS_DATA1] = {
+ .reg = RPR0521_REG_ALS_CTRL,
+ .mask = RPR0521_ALS_DATA1_GAIN_MASK,
+ .shift = RPR0521_ALS_DATA1_GAIN_SHIFT,
+ .gain = rpr0521_als_gain,
+ .size = ARRAY_SIZE(rpr0521_als_gain),
+ },
+ [RPR0521_CHAN_PXS] = {
+ .reg = RPR0521_REG_PXS_CTRL,
+ .mask = RPR0521_PXS_GAIN_MASK,
+ .shift = RPR0521_PXS_GAIN_SHIFT,
+ .gain = rpr0521_pxs_gain,
+ .size = ARRAY_SIZE(rpr0521_pxs_gain),
+ },
+};
+
+struct rpr0521_data {
+ struct i2c_client *client;
+
+ /* protect device params updates (e.g state, gain) */
+ struct mutex lock;
+
+ /* device active status */
+ bool als_dev_en;
+ bool pxs_dev_en;
+
+ /* optimize runtime pm ops - enable device only if needed */
+ bool als_ps_need_en;
+ bool pxs_ps_need_en;
+
+ struct regmap *regmap;
+};
+
+static IIO_CONST_ATTR(in_intensity_scale_available, RPR0521_ALS_SCALE_AVAIL);
+static IIO_CONST_ATTR(in_proximity_scale_available, RPR0521_PXS_SCALE_AVAIL);
+
+static struct attribute *rpr0521_attributes[] = {
+ &iio_const_attr_in_intensity_scale_available.dev_attr.attr,
+ &iio_const_attr_in_proximity_scale_available.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group rpr0521_attribute_group = {
+ .attrs = rpr0521_attributes,
+};
+
+static const struct iio_chan_spec rpr0521_channels[] = {
+ {
+ .type = IIO_INTENSITY,
+ .modified = 1,
+ .address = RPR0521_CHAN_ALS_DATA0,
+ .channel2 = IIO_MOD_LIGHT_BOTH,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ },
+ {
+ .type = IIO_INTENSITY,
+ .modified = 1,
+ .address = RPR0521_CHAN_ALS_DATA1,
+ .channel2 = IIO_MOD_LIGHT_IR,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ },
+ {
+ .type = IIO_PROXIMITY,
+ .address = RPR0521_CHAN_PXS,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ }
+};
+
+static int rpr0521_als_enable(struct rpr0521_data *data, u8 status)
+{
+ int ret;
+
+ ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
+ RPR0521_MODE_ALS_MASK,
+ status);
+ if (ret < 0)
+ return ret;
+
+ data->als_dev_en = true;
+
+ return 0;
+}
+
+static int rpr0521_pxs_enable(struct rpr0521_data *data, u8 status)
+{
+ int ret;
+
+ ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
+ RPR0521_MODE_PXS_MASK,
+ status);
+ if (ret < 0)
+ return ret;
+
+ data->pxs_dev_en = true;
+
+ return 0;
+}
+
+/**
+ * rpr0521_set_power_state - handles runtime PM state and sensors enabled status
+ *
+ * @data: rpr0521 device private data
+ * @on: state to be set for devices in @device_mask
+ * @device_mask: bitmask specifying for which device we need to update @on state
+ *
+ * We rely on rpr0521_runtime_resume to enable our @device_mask devices, but
+ * if (for example) PXS was enabled (pxs_dev_en = true) by a previous call to
+ * rpr0521_runtime_resume and we want to enable ALS we MUST set ALS enable
+ * bit of RPR0521_REG_MODE_CTRL here because rpr0521_runtime_resume will not
+ * be called twice.
+ */
+static int rpr0521_set_power_state(struct rpr0521_data *data, bool on,
+ u8 device_mask)
+{
+#ifdef CONFIG_PM
+ int ret;
+ u8 update_mask = 0;
+
+ if (device_mask & RPR0521_MODE_ALS_MASK) {
+ if (on && !data->als_ps_need_en && data->pxs_dev_en)
+ update_mask |= RPR0521_MODE_ALS_MASK;
+ else
+ data->als_ps_need_en = on;
+ }
+
+ if (device_mask & RPR0521_MODE_PXS_MASK) {
+ if (on && !data->pxs_ps_need_en && data->als_dev_en)
+ update_mask |= RPR0521_MODE_PXS_MASK;
+ else
+ data->pxs_ps_need_en = on;
+ }
+
+ if (update_mask) {
+ ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
+ update_mask, update_mask);
+ if (ret < 0)
+ return ret;
+ }
+
+ if (on) {
+ ret = pm_runtime_get_sync(&data->client->dev);
+ } else {
+ pm_runtime_mark_last_busy(&data->client->dev);
+ ret = pm_runtime_put_autosuspend(&data->client->dev);
+ }
+ if (ret < 0) {
+ dev_err(&data->client->dev,
+ "Failed: rpr0521_set_power_state for %d, ret %d\n",
+ on, ret);
+ if (on)
+ pm_runtime_put_noidle(&data->client->dev);
+
+ return ret;
+ }
+#endif
+ return 0;
+}
+
+static int rpr0521_get_gain_index(const struct rpr0521_gain *gainv, int size,
+ int val, int val2)
+{
+ int i;
+
+ for (i = 0; i < size; i++)
+ if (val == gainv[i].scale && val2 == gainv[i].uscale)
+ return i;
+
+ return -EINVAL;
+}
+
+static int rpr0521_get_gain(struct rpr0521_data *data, int chan,
+ int *val, int *val2)
+{
+ int ret, reg, idx;
+
+ ret = regmap_read(data->regmap, rpr0521_gain[chan].reg, &reg);
+ if (ret < 0)
+ return ret;
+
+ idx = (rpr0521_gain[chan].mask & reg) >> rpr0521_gain[chan].shift;
+ *val = rpr0521_gain[chan].gain[idx].scale;
+ *val2 = rpr0521_gain[chan].gain[idx].uscale;
+
+ return 0;
+}
+
+static int rpr0521_set_gain(struct rpr0521_data *data, int chan,
+ int val, int val2)
+{
+ int idx;
+
+ idx = rpr0521_get_gain_index(rpr0521_gain[chan].gain,
+ rpr0521_gain[chan].size, val, val2);
+ if (idx < 0)
+ return idx;
+
+ return regmap_update_bits(data->regmap, rpr0521_gain[chan].reg,
+ rpr0521_gain[chan].mask,
+ idx << rpr0521_gain[chan].shift);
+}
+
+static int rpr0521_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val,
+ int *val2, long mask)
+{
+ struct rpr0521_data *data = iio_priv(indio_dev);
+ int ret;
+ u8 device_mask;
+ __le16 raw_data;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (chan->type != IIO_INTENSITY && chan->type != IIO_PROXIMITY)
+ return -EINVAL;
+
+ device_mask = rpr0521_data_reg[chan->address].device_mask;
+
+ mutex_lock(&data->lock);
+ ret = rpr0521_set_power_state(data, true, device_mask);
+ if (ret < 0) {
+ mutex_unlock(&data->lock);
+ return ret;
+ }
+
+ ret = regmap_bulk_read(data->regmap,
+ rpr0521_data_reg[chan->address].address,
+ &raw_data, 2);
+ if (ret < 0) {
+ rpr0521_set_power_state(data, false, device_mask);
+ mutex_unlock(&data->lock);
+ return ret;
+ }
+
+ ret = rpr0521_set_power_state(data, false, device_mask);
+ mutex_unlock(&data->lock);
+ if (ret < 0)
+ return ret;
+
+ *val = le16_to_cpu(raw_data);
+
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ mutex_lock(&data->lock);
+ ret = rpr0521_get_gain(data, chan->address, val, val2);
+ mutex_unlock(&data->lock);
+ if (ret < 0)
+ return ret;
+
+ return IIO_VAL_INT_PLUS_MICRO;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int rpr0521_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int val,
+ int val2, long mask)
+{
+ struct rpr0521_data *data = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ mutex_lock(&data->lock);
+ ret = rpr0521_set_gain(data, chan->address, val, val2);
+ mutex_unlock(&data->lock);
+
+ return ret;
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_info rpr0521_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = rpr0521_read_raw,
+ .write_raw = rpr0521_write_raw,
+ .attrs = &rpr0521_attribute_group,
+};
+
+static int rpr0521_init(struct rpr0521_data *data)
+{
+ int ret;
+ int id;
+
+ ret = regmap_read(data->regmap, RPR0521_REG_ID, &id);
+ if (ret < 0) {
+ dev_err(&data->client->dev, "Failed to read REG_ID register\n");
+ return ret;
+ }
+
+ if (id != RPR0521_MANUFACT_ID) {
+ dev_err(&data->client->dev, "Wrong id, got %x, expected %x\n",
+ id, RPR0521_MANUFACT_ID);
+ return -ENODEV;
+ }
+
+ /* set default measurement time - 100 ms for both ALS and PS */
+ ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
+ RPR0521_MODE_MEAS_TIME_MASK,
+ RPR0521_DEFAULT_MEAS_TIME);
+ if (ret) {
+ pr_err("regmap_update_bits returned %d\n", ret);
+ return ret;
+ }
+
+ ret = rpr0521_als_enable(data, RPR0521_MODE_ALS_ENABLE);
+ if (ret < 0)
+ return ret;
+ ret = rpr0521_pxs_enable(data, RPR0521_MODE_PXS_ENABLE);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int rpr0521_poweroff(struct rpr0521_data *data)
+{
+ int ret;
+
+ ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
+ RPR0521_MODE_ALS_MASK |
+ RPR0521_MODE_PXS_MASK,
+ RPR0521_MODE_ALS_DISABLE |
+ RPR0521_MODE_PXS_DISABLE);
+ if (ret < 0)
+ return ret;
+
+ data->als_dev_en = false;
+ data->pxs_dev_en = false;
+
+ return 0;
+}
+
+static bool rpr0521_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case RPR0521_REG_MODE_CTRL:
+ case RPR0521_REG_ALS_CTRL:
+ case RPR0521_REG_PXS_CTRL:
+ return false;
+ default:
+ return true;
+ }
+}
+
+static const struct regmap_config rpr0521_regmap_config = {
+ .name = RPR0521_REGMAP_NAME,
+
+ .reg_bits = 8,
+ .val_bits = 8,
+
+ .max_register = RPR0521_REG_ID,
+ .cache_type = REGCACHE_RBTREE,
+ .volatile_reg = rpr0521_is_volatile_reg,
+};
+
+static int rpr0521_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct rpr0521_data *data;
+ struct iio_dev *indio_dev;
+ struct regmap *regmap;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ regmap = devm_regmap_init_i2c(client, &rpr0521_regmap_config);
+ if (IS_ERR(regmap)) {
+ dev_err(&client->dev, "regmap_init failed!\n");
+ return PTR_ERR(regmap);
+ }
+
+ data = iio_priv(indio_dev);
+ i2c_set_clientdata(client, indio_dev);
+ data->client = client;
+ data->regmap = regmap;
+
+ mutex_init(&data->lock);
+
+ indio_dev->dev.parent = &client->dev;
+ indio_dev->info = &rpr0521_info;
+ indio_dev->name = RPR0521_DRV_NAME;
+ indio_dev->channels = rpr0521_channels;
+ indio_dev->num_channels = ARRAY_SIZE(rpr0521_channels);
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = rpr0521_init(data);
+ if (ret < 0) {
+ dev_err(&client->dev, "rpr0521 chip init failed\n");
+ return ret;
+ }
+ ret = iio_device_register(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ ret = pm_runtime_set_active(&client->dev);
+ if (ret < 0)
+ goto err_iio_unregister;
+
+ pm_runtime_enable(&client->dev);
+ pm_runtime_set_autosuspend_delay(&client->dev, RPR0521_SLEEP_DELAY_MS);
+ pm_runtime_use_autosuspend(&client->dev);
+
+ return 0;
+
+err_iio_unregister:
+ iio_device_unregister(indio_dev);
+ return ret;
+}
+
+static int rpr0521_remove(struct i2c_client *client)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+ pm_runtime_disable(&client->dev);
+ pm_runtime_set_suspended(&client->dev);
+ pm_runtime_put_noidle(&client->dev);
+
+ iio_device_unregister(indio_dev);
+ rpr0521_poweroff(iio_priv(indio_dev));
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int rpr0521_runtime_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct rpr0521_data *data = iio_priv(indio_dev);
+ int ret;
+
+ /* disable channels and sets {als,pxs}_dev_en to false */
+ mutex_lock(&data->lock);
+ ret = rpr0521_poweroff(data);
+ mutex_unlock(&data->lock);
+
+ return ret;
+}
+
+static int rpr0521_runtime_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct rpr0521_data *data = iio_priv(indio_dev);
+ int ret;
+
+ if (data->als_ps_need_en) {
+ ret = rpr0521_als_enable(data, RPR0521_MODE_ALS_ENABLE);
+ if (ret < 0)
+ return ret;
+ data->als_ps_need_en = false;
+ }
+
+ if (data->pxs_ps_need_en) {
+ ret = rpr0521_pxs_enable(data, RPR0521_MODE_PXS_ENABLE);
+ if (ret < 0)
+ return ret;
+ data->pxs_ps_need_en = false;
+ }
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops rpr0521_pm_ops = {
+ SET_RUNTIME_PM_OPS(rpr0521_runtime_suspend,
+ rpr0521_runtime_resume, NULL)
+};
+
+static const struct acpi_device_id rpr0521_acpi_match[] = {
+ {"RPR0521", 0},
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, rpr0521_acpi_match);
+
+static const struct i2c_device_id rpr0521_id[] = {
+ {"rpr0521", 0},
+ { }
+};
+
+MODULE_DEVICE_TABLE(i2c, rpr0521_id);
+
+static struct i2c_driver rpr0521_driver = {
+ .driver = {
+ .name = RPR0521_DRV_NAME,
+ .pm = &rpr0521_pm_ops,
+ .acpi_match_table = ACPI_PTR(rpr0521_acpi_match),
+ },
+ .probe = rpr0521_probe,
+ .remove = rpr0521_remove,
+ .id_table = rpr0521_id,
+};
+
+module_i2c_driver(rpr0521_driver);
+
+MODULE_AUTHOR("Daniel Baluta <[email protected]>");
+MODULE_DESCRIPTION("RPR0521 ROHM Ambient Light and Proximity Sensor driver");
+MODULE_LICENSE("GPL v2");
--
1.9.1


2015-06-14 10:51:36

by Jonathan Cameron

[permalink] [raw]
Subject: Re: [PATCH v3] iio: light: Add support for ROHM RPR0521 sensor

On 10/06/15 15:21, Daniel Baluta wrote:
> This patch adds support for ROHM RPR0521 ambient light and proximity
> sensor. It offers raw readings for intensity and proximity.
>
> Signed-off-by: Daniel Baluta <[email protected]>
Looks good to me. A few comments inline. Only one I'd really
bother making a change for is to be consistent using genmask
for all the masks rather than just some of them.

Another thought is whether the regmap field stuff would give some
gains in this driver. What do you think?

Anyhow, if this would make the merge window I'd have taken it now
but seeing as we just missed anyway, lets tidy up these loose ends
and give others a little more time to comment.

Thanks,

Jonathan

> ---
> Changes since v2: (after Peter's review)
> * replaced calibscale with scale
> * several style fixes (new lines, spellings, etc)
> * fixed proximity interpretation. Now we have the
> following relation: high proximity <-> low distance
> * will send a follow up patch to clarify the ABI description
> and to fix all other drivers that misinterpret this.
>
> drivers/iio/light/Kconfig | 11 +
> drivers/iio/light/Makefile | 1 +
> drivers/iio/light/rpr0521.c | 622 ++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 634 insertions(+)
> create mode 100644 drivers/iio/light/rpr0521.c
>
> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
> index e6198b7..cbc4677 100644
> --- a/drivers/iio/light/Kconfig
> +++ b/drivers/iio/light/Kconfig
> @@ -168,6 +168,17 @@ config JSA1212
> To compile this driver as a module, choose M here:
> the module will be called jsa1212.
>
> +config RPR0521
> + tristate "ROHM RPR0521 ALS and proximity sensor driver"
> + depends on I2C
> + select REGMAP_I2C
> + help
> + Say Y here if you want to build support for ROHM's RPR0521
> + ambient light and proximity sensor device.
> +
> + To compile this driver as a module, choose M here:
> + the module will be called rpr0521.
> +
> config SENSORS_LM3533
> tristate "LM3533 ambient light sensor"
> depends on MFD_LM3533
> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
> index e2d50fd..adf9723 100644
> --- a/drivers/iio/light/Makefile
> +++ b/drivers/iio/light/Makefile
> @@ -19,6 +19,7 @@ obj-$(CONFIG_ISL29125) += isl29125.o
> obj-$(CONFIG_JSA1212) += jsa1212.o
> obj-$(CONFIG_SENSORS_LM3533) += lm3533-als.o
> obj-$(CONFIG_LTR501) += ltr501.o
> +obj-$(CONFIG_RPR0521) += rpr0521.o
> obj-$(CONFIG_SENSORS_TSL2563) += tsl2563.o
> obj-$(CONFIG_STK3310) += stk3310.o
> obj-$(CONFIG_TCS3414) += tcs3414.o
> diff --git a/drivers/iio/light/rpr0521.c b/drivers/iio/light/rpr0521.c
> new file mode 100644
> index 0000000..a75032ea
> --- /dev/null
> +++ b/drivers/iio/light/rpr0521.c
> @@ -0,0 +1,622 @@
> +/*
> + * RPR-0521 ROHM Ambient Light and Proximity Sensor
> + *
> + * Copyright (c) 2015, Intel Corporation.
> + *
> + * This file is subject to the terms and conditions of version 2 of
> + * the GNU General Public License. See the file COPYING in the main
> + * directory of this archive for more details.
> + *
> + * IIO driver for RPR-0521RS (7-bit I2C slave address 0x38).
> + *
> + * TODO: illuminance channel, PM support, buffer
> + */
> +
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/i2c.h>
> +#include <linux/regmap.h>
> +#include <linux/delay.h>
> +#include <linux/acpi.h>
> +
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/pm_runtime.h>
> +
> +#define RPR0521_REG_SYSTEM_CTRL 0x40
> +#define RPR0521_REG_MODE_CTRL 0x41
> +#define RPR0521_REG_ALS_CTRL 0x42
> +#define RPR0521_REG_PXS_CTRL 0x43
> +#define RPR0521_REG_PXS_DATA 0x44 /* 16-bit, little endian */
> +#define RPR0521_REG_ALS_DATA0 0x46 /* 16-bit, little endian */
> +#define RPR0521_REG_ALS_DATA1 0x48 /* 16-bit, little endian */
> +#define RPR0521_REG_ID 0x92
> +
> +#define RPR0521_MODE_ALS_MASK BIT(7)
> +#define RPR0521_MODE_PXS_MASK BIT(6)
> +#define RPR0521_MODE_MEAS_TIME_MASK GENMASK(3, 0)
> +#define RPR0521_ALS_DATA0_GAIN_MASK (BIT(4) | BIT(5))
Ideal would probably be genmask for these other masks as well.
> +#define RPR0521_ALS_DATA0_GAIN_SHIFT 4
> +#define RPR0521_ALS_DATA1_GAIN_MASK (BIT(2) | BIT(3))
> +#define RPR0521_ALS_DATA1_GAIN_SHIFT 2
> +#define RPR0521_PXS_GAIN_MASK (BIT(4) | BIT(5))
> +#define RPR0521_PXS_GAIN_SHIFT 4
> +
> +#define RPR0521_MODE_ALS_ENABLE BIT(7)
> +#define RPR0521_MODE_ALS_DISABLE 0x00
> +#define RPR0521_MODE_PXS_ENABLE BIT(6)
> +#define RPR0521_MODE_PXS_DISABLE 0x00
> +
> +#define RPR0521_PXS_MAX_VAL (BIT(13) - 1)
> +#define RPR0521_MANUFACT_ID 0xE0
> +#define RPR0521_DEFAULT_MEAS_TIME 0x06 /* ALS - 100ms, PXS - 100ms */
> +
> +#define RPR0521_DRV_NAME "RPR0521"
> +#define RPR0521_REGMAP_NAME "rpr0521_regmap"
> +
> +#define RPR0521_SLEEP_DELAY_MS 2000
> +
> +#define RPR0521_ALS_SCALE_AVAIL "0.007812 0.015625 0.5 1"
> +#define RPR0521_PXS_SCALE_AVAIL "0.125 0.5 1"
> +
> +struct rpr0521_gain {
> + int scale;
> + int uscale;
> +};
> +
> +static const struct rpr0521_gain rpr0521_als_gain[4] = {
> + {1, 0}, /* x1 */
> + {0, 500000}, /* x2 */
> + {0, 15625}, /* x64 */
> + {0, 7812}, /* x128 */
> +};
> +
> +static const struct rpr0521_gain rpr0521_pxs_gain[3] = {
> + {1, 0}, /* x1 */
> + {0, 500000}, /* x2 */
> + {0, 125000}, /* x4 */
> +};
> +
> +enum rpr0521_channel {
> + RPR0521_CHAN_ALS_DATA0,
> + RPR0521_CHAN_ALS_DATA1,
> + RPR0521_CHAN_PXS,
> +};
> +
> +struct rpr0521_reg_desc {
> + u8 address;
> + u8 device_mask;
> +};
> +
> +static const struct rpr0521_reg_desc rpr0521_data_reg[] = {
> + [RPR0521_CHAN_ALS_DATA0] = {
> + .address = RPR0521_REG_ALS_DATA0,
> + .device_mask = RPR0521_MODE_ALS_MASK,
> + },
> + [RPR0521_CHAN_ALS_DATA1] = {
> + .address = RPR0521_REG_ALS_DATA1,
> + .device_mask = RPR0521_MODE_ALS_MASK,
> + },
> + [RPR0521_CHAN_PXS] = {
> + .address = RPR0521_REG_PXS_DATA,
> + .device_mask = RPR0521_MODE_PXS_MASK,
> + },
> +};
> +
I'd have been tempted to roll the above reg_desc and this
gain_info structures together and just have a chan_info
structure containing them both. Still more a matter of
taste than anything else so I'm fine with what you have here
as well!
> +static const struct rpr0521_gain_info {
> + u8 reg;
> + u8 mask;
> + u8 shift;
> + const struct rpr0521_gain *gain;
> + int size;
> +} rpr0521_gain[] = {
> + [RPR0521_CHAN_ALS_DATA0] = {
> + .reg = RPR0521_REG_ALS_CTRL,
> + .mask = RPR0521_ALS_DATA0_GAIN_MASK,
> + .shift = RPR0521_ALS_DATA0_GAIN_SHIFT,
> + .gain = rpr0521_als_gain,
> + .size = ARRAY_SIZE(rpr0521_als_gain),
> + },
> + [RPR0521_CHAN_ALS_DATA1] = {
> + .reg = RPR0521_REG_ALS_CTRL,
> + .mask = RPR0521_ALS_DATA1_GAIN_MASK,
> + .shift = RPR0521_ALS_DATA1_GAIN_SHIFT,
> + .gain = rpr0521_als_gain,
> + .size = ARRAY_SIZE(rpr0521_als_gain),
> + },
> + [RPR0521_CHAN_PXS] = {
> + .reg = RPR0521_REG_PXS_CTRL,
> + .mask = RPR0521_PXS_GAIN_MASK,
> + .shift = RPR0521_PXS_GAIN_SHIFT,
> + .gain = rpr0521_pxs_gain,
> + .size = ARRAY_SIZE(rpr0521_pxs_gain),
> + },
> +};
> +
> +struct rpr0521_data {
> + struct i2c_client *client;
> +
> + /* protect device params updates (e.g state, gain) */
> + struct mutex lock;
> +
> + /* device active status */
> + bool als_dev_en;
> + bool pxs_dev_en;
> +
> + /* optimize runtime pm ops - enable device only if needed */
> + bool als_ps_need_en;
> + bool pxs_ps_need_en;
> +
> + struct regmap *regmap;
> +};
> +
> +static IIO_CONST_ATTR(in_intensity_scale_available, RPR0521_ALS_SCALE_AVAIL);
> +static IIO_CONST_ATTR(in_proximity_scale_available, RPR0521_PXS_SCALE_AVAIL);
> +
> +static struct attribute *rpr0521_attributes[] = {
> + &iio_const_attr_in_intensity_scale_available.dev_attr.attr,
> + &iio_const_attr_in_proximity_scale_available.dev_attr.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group rpr0521_attribute_group = {
> + .attrs = rpr0521_attributes,
> +};
> +
> +static const struct iio_chan_spec rpr0521_channels[] = {
> + {
> + .type = IIO_INTENSITY,
> + .modified = 1,
> + .address = RPR0521_CHAN_ALS_DATA0,
> + .channel2 = IIO_MOD_LIGHT_BOTH,
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE),
> + },
> + {
> + .type = IIO_INTENSITY,
> + .modified = 1,
> + .address = RPR0521_CHAN_ALS_DATA1,
> + .channel2 = IIO_MOD_LIGHT_IR,
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE),
> + },
> + {
> + .type = IIO_PROXIMITY,
> + .address = RPR0521_CHAN_PXS,
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE),
> + }
> +};
> +
> +static int rpr0521_als_enable(struct rpr0521_data *data, u8 status)
> +{
> + int ret;
> +
> + ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
> + RPR0521_MODE_ALS_MASK,
> + status);
> + if (ret < 0)
> + return ret;
> +
> + data->als_dev_en = true;
> +
> + return 0;
> +}
> +
> +static int rpr0521_pxs_enable(struct rpr0521_data *data, u8 status)
> +{
> + int ret;
> +
> + ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
> + RPR0521_MODE_PXS_MASK,
> + status);
> + if (ret < 0)
> + return ret;
> +
> + data->pxs_dev_en = true;
> +
> + return 0;
> +}
> +
> +/**
> + * rpr0521_set_power_state - handles runtime PM state and sensors enabled status
> + *
> + * @data: rpr0521 device private data
> + * @on: state to be set for devices in @device_mask
> + * @device_mask: bitmask specifying for which device we need to update @on state
> + *
> + * We rely on rpr0521_runtime_resume to enable our @device_mask devices, but
> + * if (for example) PXS was enabled (pxs_dev_en = true) by a previous call to
> + * rpr0521_runtime_resume and we want to enable ALS we MUST set ALS enable
> + * bit of RPR0521_REG_MODE_CTRL here because rpr0521_runtime_resume will not
> + * be called twice.
> + */
> +static int rpr0521_set_power_state(struct rpr0521_data *data, bool on,
> + u8 device_mask)
> +{
> +#ifdef CONFIG_PM
> + int ret;
> + u8 update_mask = 0;
> +
> + if (device_mask & RPR0521_MODE_ALS_MASK) {
> + if (on && !data->als_ps_need_en && data->pxs_dev_en)
> + update_mask |= RPR0521_MODE_ALS_MASK;
> + else
> + data->als_ps_need_en = on;
> + }
> +
> + if (device_mask & RPR0521_MODE_PXS_MASK) {
> + if (on && !data->pxs_ps_need_en && data->als_dev_en)
> + update_mask |= RPR0521_MODE_PXS_MASK;
> + else
> + data->pxs_ps_need_en = on;
> + }
> +
> + if (update_mask) {
> + ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
> + update_mask, update_mask);
> + if (ret < 0)
> + return ret;
> + }
> +
> + if (on) {
> + ret = pm_runtime_get_sync(&data->client->dev);
> + } else {
> + pm_runtime_mark_last_busy(&data->client->dev);
> + ret = pm_runtime_put_autosuspend(&data->client->dev);
> + }
> + if (ret < 0) {
> + dev_err(&data->client->dev,
> + "Failed: rpr0521_set_power_state for %d, ret %d\n",
> + on, ret);
> + if (on)
> + pm_runtime_put_noidle(&data->client->dev);
> +
> + return ret;
> + }
> +#endif
> + return 0;
> +}
> +
> +static int rpr0521_get_gain_index(const struct rpr0521_gain *gainv, int size,
> + int val, int val2)
> +{
> + int i;
> +
> + for (i = 0; i < size; i++)
> + if (val == gainv[i].scale && val2 == gainv[i].uscale)
> + return i;
> +
> + return -EINVAL;
> +}
> +
> +static int rpr0521_get_gain(struct rpr0521_data *data, int chan,
> + int *val, int *val2)
> +{
> + int ret, reg, idx;
> +
> + ret = regmap_read(data->regmap, rpr0521_gain[chan].reg, &reg);
> + if (ret < 0)
> + return ret;
> +
> + idx = (rpr0521_gain[chan].mask & reg) >> rpr0521_gain[chan].shift;
> + *val = rpr0521_gain[chan].gain[idx].scale;
> + *val2 = rpr0521_gain[chan].gain[idx].uscale;
> +
> + return 0;
> +}
> +
> +static int rpr0521_set_gain(struct rpr0521_data *data, int chan,
> + int val, int val2)
> +{
> + int idx;
> +
> + idx = rpr0521_get_gain_index(rpr0521_gain[chan].gain,
> + rpr0521_gain[chan].size, val, val2);
Marginal benefit in having the separate get_gain_index function as
only used here and very simple at that. Maybe, just worth while..
> + if (idx < 0)
> + return idx;
> +
> + return regmap_update_bits(data->regmap, rpr0521_gain[chan].reg,
> + rpr0521_gain[chan].mask,
> + idx << rpr0521_gain[chan].shift);
> +}
> +
> +static int rpr0521_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan, int *val,
> + int *val2, long mask)
> +{
> + struct rpr0521_data *data = iio_priv(indio_dev);
> + int ret;
> + u8 device_mask;
> + __le16 raw_data;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + if (chan->type != IIO_INTENSITY && chan->type != IIO_PROXIMITY)
> + return -EINVAL;
> +
> + device_mask = rpr0521_data_reg[chan->address].device_mask;
> +
> + mutex_lock(&data->lock);
> + ret = rpr0521_set_power_state(data, true, device_mask);
> + if (ret < 0) {
Fine as is, but perhaps you would have been better pulling this section
out to a separate function then using the traditional goto type error
handling to undo the relevant elements as you go rather than having repeats
of this mutex unlock for example. Not quite a complex enough case for
me to insist on it here though :)
> + mutex_unlock(&data->lock);
> + return ret;
> + }
> +
> + ret = regmap_bulk_read(data->regmap,
> + rpr0521_data_reg[chan->address].address,
> + &raw_data, 2);
> + if (ret < 0) {
> + rpr0521_set_power_state(data, false, device_mask);
> + mutex_unlock(&data->lock);
> + return ret;
> + }
> +
> + ret = rpr0521_set_power_state(data, false, device_mask);
> + mutex_unlock(&data->lock);
> + if (ret < 0)
> + return ret;
> +
> + *val = le16_to_cpu(raw_data);
> +
> + return IIO_VAL_INT;
> + case IIO_CHAN_INFO_SCALE:
> + mutex_lock(&data->lock);
> + ret = rpr0521_get_gain(data, chan->address, val, val2);
> + mutex_unlock(&data->lock);
> + if (ret < 0)
> + return ret;
> +
> + return IIO_VAL_INT_PLUS_MICRO;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int rpr0521_write_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan, int val,
> + int val2, long mask)
> +{
> + struct rpr0521_data *data = iio_priv(indio_dev);
> + int ret;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_SCALE:
> + mutex_lock(&data->lock);
> + ret = rpr0521_set_gain(data, chan->address, val, val2);
> + mutex_unlock(&data->lock);
> +
> + return ret;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static const struct iio_info rpr0521_info = {
> + .driver_module = THIS_MODULE,
> + .read_raw = rpr0521_read_raw,
> + .write_raw = rpr0521_write_raw,
> + .attrs = &rpr0521_attribute_group,
> +};
> +
> +static int rpr0521_init(struct rpr0521_data *data)
> +{
> + int ret;
> + int id;
> +
> + ret = regmap_read(data->regmap, RPR0521_REG_ID, &id);
> + if (ret < 0) {
> + dev_err(&data->client->dev, "Failed to read REG_ID register\n");
> + return ret;
> + }
> +
> + if (id != RPR0521_MANUFACT_ID) {
> + dev_err(&data->client->dev, "Wrong id, got %x, expected %x\n",
> + id, RPR0521_MANUFACT_ID);
> + return -ENODEV;
> + }
> +
> + /* set default measurement time - 100 ms for both ALS and PS */
> + ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
> + RPR0521_MODE_MEAS_TIME_MASK,
> + RPR0521_DEFAULT_MEAS_TIME);
> + if (ret) {
> + pr_err("regmap_update_bits returned %d\n", ret);
> + return ret;
> + }
> +
> + ret = rpr0521_als_enable(data, RPR0521_MODE_ALS_ENABLE);
> + if (ret < 0)
> + return ret;
> + ret = rpr0521_pxs_enable(data, RPR0521_MODE_PXS_ENABLE);
> + if (ret < 0)
> + return ret;
> +
> + return 0;
> +}
> +
> +static int rpr0521_poweroff(struct rpr0521_data *data)
> +{
> + int ret;
> +
> + ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
> + RPR0521_MODE_ALS_MASK |
> + RPR0521_MODE_PXS_MASK,
> + RPR0521_MODE_ALS_DISABLE |
> + RPR0521_MODE_PXS_DISABLE);
> + if (ret < 0)
> + return ret;
> +
> + data->als_dev_en = false;
> + data->pxs_dev_en = false;
> +
> + return 0;
> +}
> +
> +static bool rpr0521_is_volatile_reg(struct device *dev, unsigned int reg)
> +{
> + switch (reg) {
> + case RPR0521_REG_MODE_CTRL:
> + case RPR0521_REG_ALS_CTRL:
> + case RPR0521_REG_PXS_CTRL:
> + return false;
> + default:
> + return true;
> + }
> +}
> +
> +static const struct regmap_config rpr0521_regmap_config = {
> + .name = RPR0521_REGMAP_NAME,
> +
> + .reg_bits = 8,
> + .val_bits = 8,
> +
> + .max_register = RPR0521_REG_ID,
> + .cache_type = REGCACHE_RBTREE,
> + .volatile_reg = rpr0521_is_volatile_reg,
> +};
> +
> +static int rpr0521_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct rpr0521_data *data;
> + struct iio_dev *indio_dev;
> + struct regmap *regmap;
> + int ret;
> +
> + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> + if (!indio_dev)
> + return -ENOMEM;
> +
> + regmap = devm_regmap_init_i2c(client, &rpr0521_regmap_config);
> + if (IS_ERR(regmap)) {
> + dev_err(&client->dev, "regmap_init failed!\n");
> + return PTR_ERR(regmap);
> + }
> +
> + data = iio_priv(indio_dev);
> + i2c_set_clientdata(client, indio_dev);
> + data->client = client;
> + data->regmap = regmap;
> +
> + mutex_init(&data->lock);
> +
> + indio_dev->dev.parent = &client->dev;
> + indio_dev->info = &rpr0521_info;
> + indio_dev->name = RPR0521_DRV_NAME;
> + indio_dev->channels = rpr0521_channels;
> + indio_dev->num_channels = ARRAY_SIZE(rpr0521_channels);
> + indio_dev->modes = INDIO_DIRECT_MODE;
> +
> + ret = rpr0521_init(data);
> + if (ret < 0) {
> + dev_err(&client->dev, "rpr0521 chip init failed\n");
> + return ret;
> + }
> + ret = iio_device_register(indio_dev);
> + if (ret < 0)
> + return ret;
> +
> + ret = pm_runtime_set_active(&client->dev);
> + if (ret < 0)
> + goto err_iio_unregister;
> +
> + pm_runtime_enable(&client->dev);
> + pm_runtime_set_autosuspend_delay(&client->dev, RPR0521_SLEEP_DELAY_MS);
> + pm_runtime_use_autosuspend(&client->dev);
> +
> + return 0;
> +
> +err_iio_unregister:
> + iio_device_unregister(indio_dev);
> + return ret;
> +}
> +
> +static int rpr0521_remove(struct i2c_client *client)
> +{
> + struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> + pm_runtime_disable(&client->dev);
> + pm_runtime_set_suspended(&client->dev);
> + pm_runtime_put_noidle(&client->dev);
> +
> + iio_device_unregister(indio_dev);
> + rpr0521_poweroff(iio_priv(indio_dev));
> +
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int rpr0521_runtime_suspend(struct device *dev)
> +{
> + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> + struct rpr0521_data *data = iio_priv(indio_dev);
> + int ret;
> +
> + /* disable channels and sets {als,pxs}_dev_en to false */
> + mutex_lock(&data->lock);
> + ret = rpr0521_poweroff(data);
> + mutex_unlock(&data->lock);
> +
> + return ret;
> +}
> +
> +static int rpr0521_runtime_resume(struct device *dev)
> +{
> + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> + struct rpr0521_data *data = iio_priv(indio_dev);
> + int ret;
> +
> + if (data->als_ps_need_en) {
> + ret = rpr0521_als_enable(data, RPR0521_MODE_ALS_ENABLE);
> + if (ret < 0)
> + return ret;
> + data->als_ps_need_en = false;
> + }
> +
> + if (data->pxs_ps_need_en) {
> + ret = rpr0521_pxs_enable(data, RPR0521_MODE_PXS_ENABLE);
> + if (ret < 0)
> + return ret;
> + data->pxs_ps_need_en = false;
> + }
> +
> + return 0;
> +}
> +#endif
> +
> +static const struct dev_pm_ops rpr0521_pm_ops = {
> + SET_RUNTIME_PM_OPS(rpr0521_runtime_suspend,
> + rpr0521_runtime_resume, NULL)
> +};
> +
> +static const struct acpi_device_id rpr0521_acpi_match[] = {
> + {"RPR0521", 0},
> + { }
> +};
> +MODULE_DEVICE_TABLE(acpi, rpr0521_acpi_match);
> +
> +static const struct i2c_device_id rpr0521_id[] = {
> + {"rpr0521", 0},
> + { }
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, rpr0521_id);
> +
> +static struct i2c_driver rpr0521_driver = {
> + .driver = {
> + .name = RPR0521_DRV_NAME,
> + .pm = &rpr0521_pm_ops,
> + .acpi_match_table = ACPI_PTR(rpr0521_acpi_match),
> + },
> + .probe = rpr0521_probe,
> + .remove = rpr0521_remove,
> + .id_table = rpr0521_id,
> +};
> +
> +module_i2c_driver(rpr0521_driver);
> +
> +MODULE_AUTHOR("Daniel Baluta <[email protected]>");
> +MODULE_DESCRIPTION("RPR0521 ROHM Ambient Light and Proximity Sensor driver");
> +MODULE_LICENSE("GPL v2");
>

2015-06-14 11:29:05

by Daniel Baluta

[permalink] [raw]
Subject: Re: [PATCH v3] iio: light: Add support for ROHM RPR0521 sensor

On Sun, Jun 14, 2015 at 1:51 PM, Jonathan Cameron <[email protected]> wrote:
> On 10/06/15 15:21, Daniel Baluta wrote:
>> This patch adds support for ROHM RPR0521 ambient light and proximity
>> sensor. It offers raw readings for intensity and proximity.
>>
>> Signed-off-by: Daniel Baluta <[email protected]>
> Looks good to me. A few comments inline. Only one I'd really
> bother making a change for is to be consistent using genmask
> for all the masks rather than just some of them.

Agree. I will fix this.

>
> Another thought is whether the regmap field stuff would give some
> gains in this driver. What do you think?
>

Lately, I've seen that there is a strong preference for using regmap.
Personally, I like
it because I don't have to deal with deal with bit operations.

Here, the only advantage seems to be for caching gain values. Also, one future
possible benefit of regmap would be easier porting for SPI bus (if added).

So, if you don't mind I prefer leaving it like this.

> Anyhow, if this would make the merge window I'd have taken it now
> but seeing as we just missed anyway, lets tidy up these loose ends
> and give others a little more time to comment.
>
> Thanks,
>
> Jonathan
>
>> ---
>> Changes since v2: (after Peter's review)
>> * replaced calibscale with scale
>> * several style fixes (new lines, spellings, etc)
>> * fixed proximity interpretation. Now we have the
>> following relation: high proximity <-> low distance
>> * will send a follow up patch to clarify the ABI description
>> and to fix all other drivers that misinterpret this.
>>
>> drivers/iio/light/Kconfig | 11 +
>> drivers/iio/light/Makefile | 1 +
>> drivers/iio/light/rpr0521.c | 622 ++++++++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 634 insertions(+)
>> create mode 100644 drivers/iio/light/rpr0521.c
>>
>> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
>> index e6198b7..cbc4677 100644
>> --- a/drivers/iio/light/Kconfig
>> +++ b/drivers/iio/light/Kconfig
>> @@ -168,6 +168,17 @@ config JSA1212
>> To compile this driver as a module, choose M here:
>> the module will be called jsa1212.
>>
>> +config RPR0521
>> + tristate "ROHM RPR0521 ALS and proximity sensor driver"
>> + depends on I2C
>> + select REGMAP_I2C
>> + help
>> + Say Y here if you want to build support for ROHM's RPR0521
>> + ambient light and proximity sensor device.
>> +
>> + To compile this driver as a module, choose M here:
>> + the module will be called rpr0521.
>> +
>> config SENSORS_LM3533
>> tristate "LM3533 ambient light sensor"
>> depends on MFD_LM3533
>> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
>> index e2d50fd..adf9723 100644
>> --- a/drivers/iio/light/Makefile
>> +++ b/drivers/iio/light/Makefile
>> @@ -19,6 +19,7 @@ obj-$(CONFIG_ISL29125) += isl29125.o
>> obj-$(CONFIG_JSA1212) += jsa1212.o
>> obj-$(CONFIG_SENSORS_LM3533) += lm3533-als.o
>> obj-$(CONFIG_LTR501) += ltr501.o
>> +obj-$(CONFIG_RPR0521) += rpr0521.o
>> obj-$(CONFIG_SENSORS_TSL2563) += tsl2563.o
>> obj-$(CONFIG_STK3310) += stk3310.o
>> obj-$(CONFIG_TCS3414) += tcs3414.o
>> diff --git a/drivers/iio/light/rpr0521.c b/drivers/iio/light/rpr0521.c
>> new file mode 100644
>> index 0000000..a75032ea
>> --- /dev/null
>> +++ b/drivers/iio/light/rpr0521.c
>> @@ -0,0 +1,622 @@
>> +/*
>> + * RPR-0521 ROHM Ambient Light and Proximity Sensor
>> + *
>> + * Copyright (c) 2015, Intel Corporation.
>> + *
>> + * This file is subject to the terms and conditions of version 2 of
>> + * the GNU General Public License. See the file COPYING in the main
>> + * directory of this archive for more details.
>> + *
>> + * IIO driver for RPR-0521RS (7-bit I2C slave address 0x38).
>> + *
>> + * TODO: illuminance channel, PM support, buffer
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/init.h>
>> +#include <linux/i2c.h>
>> +#include <linux/regmap.h>
>> +#include <linux/delay.h>
>> +#include <linux/acpi.h>
>> +
>> +#include <linux/iio/iio.h>
>> +#include <linux/iio/sysfs.h>
>> +#include <linux/pm_runtime.h>
>> +
>> +#define RPR0521_REG_SYSTEM_CTRL 0x40
>> +#define RPR0521_REG_MODE_CTRL 0x41
>> +#define RPR0521_REG_ALS_CTRL 0x42
>> +#define RPR0521_REG_PXS_CTRL 0x43
>> +#define RPR0521_REG_PXS_DATA 0x44 /* 16-bit, little endian */
>> +#define RPR0521_REG_ALS_DATA0 0x46 /* 16-bit, little endian */
>> +#define RPR0521_REG_ALS_DATA1 0x48 /* 16-bit, little endian */
>> +#define RPR0521_REG_ID 0x92
>> +
>> +#define RPR0521_MODE_ALS_MASK BIT(7)
>> +#define RPR0521_MODE_PXS_MASK BIT(6)
>> +#define RPR0521_MODE_MEAS_TIME_MASK GENMASK(3, 0)
>> +#define RPR0521_ALS_DATA0_GAIN_MASK (BIT(4) | BIT(5))
> Ideal would probably be genmask for these other masks as well.

Ok.

>> +#define RPR0521_ALS_DATA0_GAIN_SHIFT 4
>> +#define RPR0521_ALS_DATA1_GAIN_MASK (BIT(2) | BIT(3))
>> +#define RPR0521_ALS_DATA1_GAIN_SHIFT 2
>> +#define RPR0521_PXS_GAIN_MASK (BIT(4) | BIT(5))
>> +#define RPR0521_PXS_GAIN_SHIFT 4
>> +
>> +#define RPR0521_MODE_ALS_ENABLE BIT(7)
>> +#define RPR0521_MODE_ALS_DISABLE 0x00
>> +#define RPR0521_MODE_PXS_ENABLE BIT(6)
>> +#define RPR0521_MODE_PXS_DISABLE 0x00
>> +
>> +#define RPR0521_PXS_MAX_VAL (BIT(13) - 1)
>> +#define RPR0521_MANUFACT_ID 0xE0
>> +#define RPR0521_DEFAULT_MEAS_TIME 0x06 /* ALS - 100ms, PXS - 100ms */
>> +
>> +#define RPR0521_DRV_NAME "RPR0521"
>> +#define RPR0521_REGMAP_NAME "rpr0521_regmap"
>> +
>> +#define RPR0521_SLEEP_DELAY_MS 2000
>> +
>> +#define RPR0521_ALS_SCALE_AVAIL "0.007812 0.015625 0.5 1"
>> +#define RPR0521_PXS_SCALE_AVAIL "0.125 0.5 1"
>> +
>> +struct rpr0521_gain {
>> + int scale;
>> + int uscale;
>> +};
>> +
>> +static const struct rpr0521_gain rpr0521_als_gain[4] = {
>> + {1, 0}, /* x1 */
>> + {0, 500000}, /* x2 */
>> + {0, 15625}, /* x64 */
>> + {0, 7812}, /* x128 */
>> +};
>> +
>> +static const struct rpr0521_gain rpr0521_pxs_gain[3] = {
>> + {1, 0}, /* x1 */
>> + {0, 500000}, /* x2 */
>> + {0, 125000}, /* x4 */
>> +};
>> +
>> +enum rpr0521_channel {
>> + RPR0521_CHAN_ALS_DATA0,
>> + RPR0521_CHAN_ALS_DATA1,
>> + RPR0521_CHAN_PXS,
>> +};
>> +
>> +struct rpr0521_reg_desc {
>> + u8 address;
>> + u8 device_mask;
>> +};
>> +
>> +static const struct rpr0521_reg_desc rpr0521_data_reg[] = {
>> + [RPR0521_CHAN_ALS_DATA0] = {
>> + .address = RPR0521_REG_ALS_DATA0,
>> + .device_mask = RPR0521_MODE_ALS_MASK,
>> + },
>> + [RPR0521_CHAN_ALS_DATA1] = {
>> + .address = RPR0521_REG_ALS_DATA1,
>> + .device_mask = RPR0521_MODE_ALS_MASK,
>> + },
>> + [RPR0521_CHAN_PXS] = {
>> + .address = RPR0521_REG_PXS_DATA,
>> + .device_mask = RPR0521_MODE_PXS_MASK,
>> + },
>> +};
>> +
> I'd have been tempted to roll the above reg_desc and this
> gain_info structures together and just have a chan_info
> structure containing them both. Still more a matter of
> taste than anything else so I'm fine with what you have here
> as well!

I will have a closer look when sending v4.

>> +static const struct rpr0521_gain_info {
>> + u8 reg;
>> + u8 mask;
>> + u8 shift;
>> + const struct rpr0521_gain *gain;
>> + int size;
>> +} rpr0521_gain[] = {
>> + [RPR0521_CHAN_ALS_DATA0] = {
>> + .reg = RPR0521_REG_ALS_CTRL,
>> + .mask = RPR0521_ALS_DATA0_GAIN_MASK,
>> + .shift = RPR0521_ALS_DATA0_GAIN_SHIFT,
>> + .gain = rpr0521_als_gain,
>> + .size = ARRAY_SIZE(rpr0521_als_gain),
>> + },
>> + [RPR0521_CHAN_ALS_DATA1] = {
>> + .reg = RPR0521_REG_ALS_CTRL,
>> + .mask = RPR0521_ALS_DATA1_GAIN_MASK,
>> + .shift = RPR0521_ALS_DATA1_GAIN_SHIFT,
>> + .gain = rpr0521_als_gain,
>> + .size = ARRAY_SIZE(rpr0521_als_gain),
>> + },
>> + [RPR0521_CHAN_PXS] = {
>> + .reg = RPR0521_REG_PXS_CTRL,
>> + .mask = RPR0521_PXS_GAIN_MASK,
>> + .shift = RPR0521_PXS_GAIN_SHIFT,
>> + .gain = rpr0521_pxs_gain,
>> + .size = ARRAY_SIZE(rpr0521_pxs_gain),
>> + },
>> +};
>> +
>> +struct rpr0521_data {
>> + struct i2c_client *client;
>> +
>> + /* protect device params updates (e.g state, gain) */
>> + struct mutex lock;
>> +
>> + /* device active status */
>> + bool als_dev_en;
>> + bool pxs_dev_en;
>> +
>> + /* optimize runtime pm ops - enable device only if needed */
>> + bool als_ps_need_en;
>> + bool pxs_ps_need_en;
>> +
>> + struct regmap *regmap;
>> +};
>> +
>> +static IIO_CONST_ATTR(in_intensity_scale_available, RPR0521_ALS_SCALE_AVAIL);
>> +static IIO_CONST_ATTR(in_proximity_scale_available, RPR0521_PXS_SCALE_AVAIL);
>> +
>> +static struct attribute *rpr0521_attributes[] = {
>> + &iio_const_attr_in_intensity_scale_available.dev_attr.attr,
>> + &iio_const_attr_in_proximity_scale_available.dev_attr.attr,
>> + NULL,
>> +};
>> +
>> +static const struct attribute_group rpr0521_attribute_group = {
>> + .attrs = rpr0521_attributes,
>> +};
>> +
>> +static const struct iio_chan_spec rpr0521_channels[] = {
>> + {
>> + .type = IIO_INTENSITY,
>> + .modified = 1,
>> + .address = RPR0521_CHAN_ALS_DATA0,
>> + .channel2 = IIO_MOD_LIGHT_BOTH,
>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> + BIT(IIO_CHAN_INFO_SCALE),
>> + },
>> + {
>> + .type = IIO_INTENSITY,
>> + .modified = 1,
>> + .address = RPR0521_CHAN_ALS_DATA1,
>> + .channel2 = IIO_MOD_LIGHT_IR,
>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> + BIT(IIO_CHAN_INFO_SCALE),
>> + },
>> + {
>> + .type = IIO_PROXIMITY,
>> + .address = RPR0521_CHAN_PXS,
>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> + BIT(IIO_CHAN_INFO_SCALE),
>> + }
>> +};
>> +
>> +static int rpr0521_als_enable(struct rpr0521_data *data, u8 status)
>> +{
>> + int ret;
>> +
>> + ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
>> + RPR0521_MODE_ALS_MASK,
>> + status);
>> + if (ret < 0)
>> + return ret;
>> +
>> + data->als_dev_en = true;
>> +
>> + return 0;
>> +}
>> +
>> +static int rpr0521_pxs_enable(struct rpr0521_data *data, u8 status)
>> +{
>> + int ret;
>> +
>> + ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
>> + RPR0521_MODE_PXS_MASK,
>> + status);
>> + if (ret < 0)
>> + return ret;
>> +
>> + data->pxs_dev_en = true;
>> +
>> + return 0;
>> +}
>> +
>> +/**
>> + * rpr0521_set_power_state - handles runtime PM state and sensors enabled status
>> + *
>> + * @data: rpr0521 device private data
>> + * @on: state to be set for devices in @device_mask
>> + * @device_mask: bitmask specifying for which device we need to update @on state
>> + *
>> + * We rely on rpr0521_runtime_resume to enable our @device_mask devices, but
>> + * if (for example) PXS was enabled (pxs_dev_en = true) by a previous call to
>> + * rpr0521_runtime_resume and we want to enable ALS we MUST set ALS enable
>> + * bit of RPR0521_REG_MODE_CTRL here because rpr0521_runtime_resume will not
>> + * be called twice.
>> + */
>> +static int rpr0521_set_power_state(struct rpr0521_data *data, bool on,
>> + u8 device_mask)
>> +{
>> +#ifdef CONFIG_PM
>> + int ret;
>> + u8 update_mask = 0;
>> +
>> + if (device_mask & RPR0521_MODE_ALS_MASK) {
>> + if (on && !data->als_ps_need_en && data->pxs_dev_en)
>> + update_mask |= RPR0521_MODE_ALS_MASK;
>> + else
>> + data->als_ps_need_en = on;
>> + }
>> +
>> + if (device_mask & RPR0521_MODE_PXS_MASK) {
>> + if (on && !data->pxs_ps_need_en && data->als_dev_en)
>> + update_mask |= RPR0521_MODE_PXS_MASK;
>> + else
>> + data->pxs_ps_need_en = on;
>> + }
>> +
>> + if (update_mask) {
>> + ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
>> + update_mask, update_mask);
>> + if (ret < 0)
>> + return ret;
>> + }
>> +
>> + if (on) {
>> + ret = pm_runtime_get_sync(&data->client->dev);
>> + } else {
>> + pm_runtime_mark_last_busy(&data->client->dev);
>> + ret = pm_runtime_put_autosuspend(&data->client->dev);
>> + }
>> + if (ret < 0) {
>> + dev_err(&data->client->dev,
>> + "Failed: rpr0521_set_power_state for %d, ret %d\n",
>> + on, ret);
>> + if (on)
>> + pm_runtime_put_noidle(&data->client->dev);
>> +
>> + return ret;
>> + }
>> +#endif
>> + return 0;
>> +}
>> +
>> +static int rpr0521_get_gain_index(const struct rpr0521_gain *gainv, int size,
>> + int val, int val2)
>> +{
>> + int i;
>> +
>> + for (i = 0; i < size; i++)
>> + if (val == gainv[i].scale && val2 == gainv[i].uscale)
>> + return i;
>> +
>> + return -EINVAL;
>> +}
>> +
>> +static int rpr0521_get_gain(struct rpr0521_data *data, int chan,
>> + int *val, int *val2)
>> +{
>> + int ret, reg, idx;
>> +
>> + ret = regmap_read(data->regmap, rpr0521_gain[chan].reg, &reg);
>> + if (ret < 0)
>> + return ret;
>> +
>> + idx = (rpr0521_gain[chan].mask & reg) >> rpr0521_gain[chan].shift;
>> + *val = rpr0521_gain[chan].gain[idx].scale;
>> + *val2 = rpr0521_gain[chan].gain[idx].uscale;
>> +
>> + return 0;
>> +}
>> +
>> +static int rpr0521_set_gain(struct rpr0521_data *data, int chan,
>> + int val, int val2)
>> +{
>> + int idx;
>> +
>> + idx = rpr0521_get_gain_index(rpr0521_gain[chan].gain,
>> + rpr0521_gain[chan].size, val, val2);
> Marginal benefit in having the separate get_gain_index function as
> only used here and very simple at that. Maybe, just worth while..

Agree with this.

>> + if (idx < 0)
>> + return idx;
>> +
>> + return regmap_update_bits(data->regmap, rpr0521_gain[chan].reg,
>> + rpr0521_gain[chan].mask,
>> + idx << rpr0521_gain[chan].shift);
>> +}
>> +
>> +static int rpr0521_read_raw(struct iio_dev *indio_dev,
>> + struct iio_chan_spec const *chan, int *val,
>> + int *val2, long mask)
>> +{
>> + struct rpr0521_data *data = iio_priv(indio_dev);
>> + int ret;
>> + u8 device_mask;
>> + __le16 raw_data;
>> +
>> + switch (mask) {
>> + case IIO_CHAN_INFO_RAW:
>> + if (chan->type != IIO_INTENSITY && chan->type != IIO_PROXIMITY)
>> + return -EINVAL;
>> +
>> + device_mask = rpr0521_data_reg[chan->address].device_mask;
>> +
>> + mutex_lock(&data->lock);
>> + ret = rpr0521_set_power_state(data, true, device_mask);
>> + if (ret < 0) {
> Fine as is, but perhaps you would have been better pulling this section
> out to a separate function then using the traditional goto type error
> handling to undo the relevant elements as you go rather than having repeats
> of this mutex unlock for example. Not quite a complex enough case for
> me to insist on it here though :)
>> + mutex_unlock(&data->lock);
>> + return ret;

I see, it seems ok as it is. I'll try to see if using goto makes code easier
to read.

thanks,
Daniel.

2015-06-14 14:02:54

by Jonathan Cameron

[permalink] [raw]
Subject: Re: [PATCH v3] iio: light: Add support for ROHM RPR0521 sensor

On 14/06/15 12:28, Daniel Baluta wrote:
> On Sun, Jun 14, 2015 at 1:51 PM, Jonathan Cameron <[email protected]> wrote:
>> On 10/06/15 15:21, Daniel Baluta wrote:
>>> This patch adds support for ROHM RPR0521 ambient light and proximity
>>> sensor. It offers raw readings for intensity and proximity.
>>>
>>> Signed-off-by: Daniel Baluta <[email protected]>
>> Looks good to me. A few comments inline. Only one I'd really
>> bother making a change for is to be consistent using genmask
>> for all the masks rather than just some of them.
>
> Agree. I will fix this.
>
>>
>> Another thought is whether the regmap field stuff would give some
>> gains in this driver. What do you think?
>>
>
> Lately, I've seen that there is a strong preference for using regmap.
> Personally, I like
> it because I don't have to deal with deal with bit operations.
>
> Here, the only advantage seems to be for caching gain values. Also, one future
> possible benefit of regmap would be easier porting for SPI bus (if added).
>
> So, if you don't mind I prefer leaving it like this.
That's fine. Using the field stuff mostly only gives a small gain in clarity
and that only once you have looked up how it works :)

Jonathan
>
>> Anyhow, if this would make the merge window I'd have taken it now
>> but seeing as we just missed anyway, lets tidy up these loose ends
>> and give others a little more time to comment.
>>
>> Thanks,
>>
>> Jonathan
>>
>>> ---
>>> Changes since v2: (after Peter's review)
>>> * replaced calibscale with scale
>>> * several style fixes (new lines, spellings, etc)
>>> * fixed proximity interpretation. Now we have the
>>> following relation: high proximity <-> low distance
>>> * will send a follow up patch to clarify the ABI description
>>> and to fix all other drivers that misinterpret this.
>>>
>>> drivers/iio/light/Kconfig | 11 +
>>> drivers/iio/light/Makefile | 1 +
>>> drivers/iio/light/rpr0521.c | 622 ++++++++++++++++++++++++++++++++++++++++++++
>>> 3 files changed, 634 insertions(+)
>>> create mode 100644 drivers/iio/light/rpr0521.c
>>>
>>> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
>>> index e6198b7..cbc4677 100644
>>> --- a/drivers/iio/light/Kconfig
>>> +++ b/drivers/iio/light/Kconfig
>>> @@ -168,6 +168,17 @@ config JSA1212
>>> To compile this driver as a module, choose M here:
>>> the module will be called jsa1212.
>>>
>>> +config RPR0521
>>> + tristate "ROHM RPR0521 ALS and proximity sensor driver"
>>> + depends on I2C
>>> + select REGMAP_I2C
>>> + help
>>> + Say Y here if you want to build support for ROHM's RPR0521
>>> + ambient light and proximity sensor device.
>>> +
>>> + To compile this driver as a module, choose M here:
>>> + the module will be called rpr0521.
>>> +
>>> config SENSORS_LM3533
>>> tristate "LM3533 ambient light sensor"
>>> depends on MFD_LM3533
>>> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
>>> index e2d50fd..adf9723 100644
>>> --- a/drivers/iio/light/Makefile
>>> +++ b/drivers/iio/light/Makefile
>>> @@ -19,6 +19,7 @@ obj-$(CONFIG_ISL29125) += isl29125.o
>>> obj-$(CONFIG_JSA1212) += jsa1212.o
>>> obj-$(CONFIG_SENSORS_LM3533) += lm3533-als.o
>>> obj-$(CONFIG_LTR501) += ltr501.o
>>> +obj-$(CONFIG_RPR0521) += rpr0521.o
>>> obj-$(CONFIG_SENSORS_TSL2563) += tsl2563.o
>>> obj-$(CONFIG_STK3310) += stk3310.o
>>> obj-$(CONFIG_TCS3414) += tcs3414.o
>>> diff --git a/drivers/iio/light/rpr0521.c b/drivers/iio/light/rpr0521.c
>>> new file mode 100644
>>> index 0000000..a75032ea
>>> --- /dev/null
>>> +++ b/drivers/iio/light/rpr0521.c
>>> @@ -0,0 +1,622 @@
>>> +/*
>>> + * RPR-0521 ROHM Ambient Light and Proximity Sensor
>>> + *
>>> + * Copyright (c) 2015, Intel Corporation.
>>> + *
>>> + * This file is subject to the terms and conditions of version 2 of
>>> + * the GNU General Public License. See the file COPYING in the main
>>> + * directory of this archive for more details.
>>> + *
>>> + * IIO driver for RPR-0521RS (7-bit I2C slave address 0x38).
>>> + *
>>> + * TODO: illuminance channel, PM support, buffer
>>> + */
>>> +
>>> +#include <linux/module.h>
>>> +#include <linux/init.h>
>>> +#include <linux/i2c.h>
>>> +#include <linux/regmap.h>
>>> +#include <linux/delay.h>
>>> +#include <linux/acpi.h>
>>> +
>>> +#include <linux/iio/iio.h>
>>> +#include <linux/iio/sysfs.h>
>>> +#include <linux/pm_runtime.h>
>>> +
>>> +#define RPR0521_REG_SYSTEM_CTRL 0x40
>>> +#define RPR0521_REG_MODE_CTRL 0x41
>>> +#define RPR0521_REG_ALS_CTRL 0x42
>>> +#define RPR0521_REG_PXS_CTRL 0x43
>>> +#define RPR0521_REG_PXS_DATA 0x44 /* 16-bit, little endian */
>>> +#define RPR0521_REG_ALS_DATA0 0x46 /* 16-bit, little endian */
>>> +#define RPR0521_REG_ALS_DATA1 0x48 /* 16-bit, little endian */
>>> +#define RPR0521_REG_ID 0x92
>>> +
>>> +#define RPR0521_MODE_ALS_MASK BIT(7)
>>> +#define RPR0521_MODE_PXS_MASK BIT(6)
>>> +#define RPR0521_MODE_MEAS_TIME_MASK GENMASK(3, 0)
>>> +#define RPR0521_ALS_DATA0_GAIN_MASK (BIT(4) | BIT(5))
>> Ideal would probably be genmask for these other masks as well.
>
> Ok.
>
>>> +#define RPR0521_ALS_DATA0_GAIN_SHIFT 4
>>> +#define RPR0521_ALS_DATA1_GAIN_MASK (BIT(2) | BIT(3))
>>> +#define RPR0521_ALS_DATA1_GAIN_SHIFT 2
>>> +#define RPR0521_PXS_GAIN_MASK (BIT(4) | BIT(5))
>>> +#define RPR0521_PXS_GAIN_SHIFT 4
>>> +
>>> +#define RPR0521_MODE_ALS_ENABLE BIT(7)
>>> +#define RPR0521_MODE_ALS_DISABLE 0x00
>>> +#define RPR0521_MODE_PXS_ENABLE BIT(6)
>>> +#define RPR0521_MODE_PXS_DISABLE 0x00
>>> +
>>> +#define RPR0521_PXS_MAX_VAL (BIT(13) - 1)
>>> +#define RPR0521_MANUFACT_ID 0xE0
>>> +#define RPR0521_DEFAULT_MEAS_TIME 0x06 /* ALS - 100ms, PXS - 100ms */
>>> +
>>> +#define RPR0521_DRV_NAME "RPR0521"
>>> +#define RPR0521_REGMAP_NAME "rpr0521_regmap"
>>> +
>>> +#define RPR0521_SLEEP_DELAY_MS 2000
>>> +
>>> +#define RPR0521_ALS_SCALE_AVAIL "0.007812 0.015625 0.5 1"
>>> +#define RPR0521_PXS_SCALE_AVAIL "0.125 0.5 1"
>>> +
>>> +struct rpr0521_gain {
>>> + int scale;
>>> + int uscale;
>>> +};
>>> +
>>> +static const struct rpr0521_gain rpr0521_als_gain[4] = {
>>> + {1, 0}, /* x1 */
>>> + {0, 500000}, /* x2 */
>>> + {0, 15625}, /* x64 */
>>> + {0, 7812}, /* x128 */
>>> +};
>>> +
>>> +static const struct rpr0521_gain rpr0521_pxs_gain[3] = {
>>> + {1, 0}, /* x1 */
>>> + {0, 500000}, /* x2 */
>>> + {0, 125000}, /* x4 */
>>> +};
>>> +
>>> +enum rpr0521_channel {
>>> + RPR0521_CHAN_ALS_DATA0,
>>> + RPR0521_CHAN_ALS_DATA1,
>>> + RPR0521_CHAN_PXS,
>>> +};
>>> +
>>> +struct rpr0521_reg_desc {
>>> + u8 address;
>>> + u8 device_mask;
>>> +};
>>> +
>>> +static const struct rpr0521_reg_desc rpr0521_data_reg[] = {
>>> + [RPR0521_CHAN_ALS_DATA0] = {
>>> + .address = RPR0521_REG_ALS_DATA0,
>>> + .device_mask = RPR0521_MODE_ALS_MASK,
>>> + },
>>> + [RPR0521_CHAN_ALS_DATA1] = {
>>> + .address = RPR0521_REG_ALS_DATA1,
>>> + .device_mask = RPR0521_MODE_ALS_MASK,
>>> + },
>>> + [RPR0521_CHAN_PXS] = {
>>> + .address = RPR0521_REG_PXS_DATA,
>>> + .device_mask = RPR0521_MODE_PXS_MASK,
>>> + },
>>> +};
>>> +
>> I'd have been tempted to roll the above reg_desc and this
>> gain_info structures together and just have a chan_info
>> structure containing them both. Still more a matter of
>> taste than anything else so I'm fine with what you have here
>> as well!
>
> I will have a closer look when sending v4.
>
>>> +static const struct rpr0521_gain_info {
>>> + u8 reg;
>>> + u8 mask;
>>> + u8 shift;
>>> + const struct rpr0521_gain *gain;
>>> + int size;
>>> +} rpr0521_gain[] = {
>>> + [RPR0521_CHAN_ALS_DATA0] = {
>>> + .reg = RPR0521_REG_ALS_CTRL,
>>> + .mask = RPR0521_ALS_DATA0_GAIN_MASK,
>>> + .shift = RPR0521_ALS_DATA0_GAIN_SHIFT,
>>> + .gain = rpr0521_als_gain,
>>> + .size = ARRAY_SIZE(rpr0521_als_gain),
>>> + },
>>> + [RPR0521_CHAN_ALS_DATA1] = {
>>> + .reg = RPR0521_REG_ALS_CTRL,
>>> + .mask = RPR0521_ALS_DATA1_GAIN_MASK,
>>> + .shift = RPR0521_ALS_DATA1_GAIN_SHIFT,
>>> + .gain = rpr0521_als_gain,
>>> + .size = ARRAY_SIZE(rpr0521_als_gain),
>>> + },
>>> + [RPR0521_CHAN_PXS] = {
>>> + .reg = RPR0521_REG_PXS_CTRL,
>>> + .mask = RPR0521_PXS_GAIN_MASK,
>>> + .shift = RPR0521_PXS_GAIN_SHIFT,
>>> + .gain = rpr0521_pxs_gain,
>>> + .size = ARRAY_SIZE(rpr0521_pxs_gain),
>>> + },
>>> +};
>>> +
>>> +struct rpr0521_data {
>>> + struct i2c_client *client;
>>> +
>>> + /* protect device params updates (e.g state, gain) */
>>> + struct mutex lock;
>>> +
>>> + /* device active status */
>>> + bool als_dev_en;
>>> + bool pxs_dev_en;
>>> +
>>> + /* optimize runtime pm ops - enable device only if needed */
>>> + bool als_ps_need_en;
>>> + bool pxs_ps_need_en;
>>> +
>>> + struct regmap *regmap;
>>> +};
>>> +
>>> +static IIO_CONST_ATTR(in_intensity_scale_available, RPR0521_ALS_SCALE_AVAIL);
>>> +static IIO_CONST_ATTR(in_proximity_scale_available, RPR0521_PXS_SCALE_AVAIL);
>>> +
>>> +static struct attribute *rpr0521_attributes[] = {
>>> + &iio_const_attr_in_intensity_scale_available.dev_attr.attr,
>>> + &iio_const_attr_in_proximity_scale_available.dev_attr.attr,
>>> + NULL,
>>> +};
>>> +
>>> +static const struct attribute_group rpr0521_attribute_group = {
>>> + .attrs = rpr0521_attributes,
>>> +};
>>> +
>>> +static const struct iio_chan_spec rpr0521_channels[] = {
>>> + {
>>> + .type = IIO_INTENSITY,
>>> + .modified = 1,
>>> + .address = RPR0521_CHAN_ALS_DATA0,
>>> + .channel2 = IIO_MOD_LIGHT_BOTH,
>>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>>> + BIT(IIO_CHAN_INFO_SCALE),
>>> + },
>>> + {
>>> + .type = IIO_INTENSITY,
>>> + .modified = 1,
>>> + .address = RPR0521_CHAN_ALS_DATA1,
>>> + .channel2 = IIO_MOD_LIGHT_IR,
>>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>>> + BIT(IIO_CHAN_INFO_SCALE),
>>> + },
>>> + {
>>> + .type = IIO_PROXIMITY,
>>> + .address = RPR0521_CHAN_PXS,
>>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>>> + BIT(IIO_CHAN_INFO_SCALE),
>>> + }
>>> +};
>>> +
>>> +static int rpr0521_als_enable(struct rpr0521_data *data, u8 status)
>>> +{
>>> + int ret;
>>> +
>>> + ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
>>> + RPR0521_MODE_ALS_MASK,
>>> + status);
>>> + if (ret < 0)
>>> + return ret;
>>> +
>>> + data->als_dev_en = true;
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int rpr0521_pxs_enable(struct rpr0521_data *data, u8 status)
>>> +{
>>> + int ret;
>>> +
>>> + ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
>>> + RPR0521_MODE_PXS_MASK,
>>> + status);
>>> + if (ret < 0)
>>> + return ret;
>>> +
>>> + data->pxs_dev_en = true;
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +/**
>>> + * rpr0521_set_power_state - handles runtime PM state and sensors enabled status
>>> + *
>>> + * @data: rpr0521 device private data
>>> + * @on: state to be set for devices in @device_mask
>>> + * @device_mask: bitmask specifying for which device we need to update @on state
>>> + *
>>> + * We rely on rpr0521_runtime_resume to enable our @device_mask devices, but
>>> + * if (for example) PXS was enabled (pxs_dev_en = true) by a previous call to
>>> + * rpr0521_runtime_resume and we want to enable ALS we MUST set ALS enable
>>> + * bit of RPR0521_REG_MODE_CTRL here because rpr0521_runtime_resume will not
>>> + * be called twice.
>>> + */
>>> +static int rpr0521_set_power_state(struct rpr0521_data *data, bool on,
>>> + u8 device_mask)
>>> +{
>>> +#ifdef CONFIG_PM
>>> + int ret;
>>> + u8 update_mask = 0;
>>> +
>>> + if (device_mask & RPR0521_MODE_ALS_MASK) {
>>> + if (on && !data->als_ps_need_en && data->pxs_dev_en)
>>> + update_mask |= RPR0521_MODE_ALS_MASK;
>>> + else
>>> + data->als_ps_need_en = on;
>>> + }
>>> +
>>> + if (device_mask & RPR0521_MODE_PXS_MASK) {
>>> + if (on && !data->pxs_ps_need_en && data->als_dev_en)
>>> + update_mask |= RPR0521_MODE_PXS_MASK;
>>> + else
>>> + data->pxs_ps_need_en = on;
>>> + }
>>> +
>>> + if (update_mask) {
>>> + ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
>>> + update_mask, update_mask);
>>> + if (ret < 0)
>>> + return ret;
>>> + }
>>> +
>>> + if (on) {
>>> + ret = pm_runtime_get_sync(&data->client->dev);
>>> + } else {
>>> + pm_runtime_mark_last_busy(&data->client->dev);
>>> + ret = pm_runtime_put_autosuspend(&data->client->dev);
>>> + }
>>> + if (ret < 0) {
>>> + dev_err(&data->client->dev,
>>> + "Failed: rpr0521_set_power_state for %d, ret %d\n",
>>> + on, ret);
>>> + if (on)
>>> + pm_runtime_put_noidle(&data->client->dev);
>>> +
>>> + return ret;
>>> + }
>>> +#endif
>>> + return 0;
>>> +}
>>> +
>>> +static int rpr0521_get_gain_index(const struct rpr0521_gain *gainv, int size,
>>> + int val, int val2)
>>> +{
>>> + int i;
>>> +
>>> + for (i = 0; i < size; i++)
>>> + if (val == gainv[i].scale && val2 == gainv[i].uscale)
>>> + return i;
>>> +
>>> + return -EINVAL;
>>> +}
>>> +
>>> +static int rpr0521_get_gain(struct rpr0521_data *data, int chan,
>>> + int *val, int *val2)
>>> +{
>>> + int ret, reg, idx;
>>> +
>>> + ret = regmap_read(data->regmap, rpr0521_gain[chan].reg, &reg);
>>> + if (ret < 0)
>>> + return ret;
>>> +
>>> + idx = (rpr0521_gain[chan].mask & reg) >> rpr0521_gain[chan].shift;
>>> + *val = rpr0521_gain[chan].gain[idx].scale;
>>> + *val2 = rpr0521_gain[chan].gain[idx].uscale;
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int rpr0521_set_gain(struct rpr0521_data *data, int chan,
>>> + int val, int val2)
>>> +{
>>> + int idx;
>>> +
>>> + idx = rpr0521_get_gain_index(rpr0521_gain[chan].gain,
>>> + rpr0521_gain[chan].size, val, val2);
>> Marginal benefit in having the separate get_gain_index function as
>> only used here and very simple at that. Maybe, just worth while..
>
> Agree with this.
>
>>> + if (idx < 0)
>>> + return idx;
>>> +
>>> + return regmap_update_bits(data->regmap, rpr0521_gain[chan].reg,
>>> + rpr0521_gain[chan].mask,
>>> + idx << rpr0521_gain[chan].shift);
>>> +}
>>> +
>>> +static int rpr0521_read_raw(struct iio_dev *indio_dev,
>>> + struct iio_chan_spec const *chan, int *val,
>>> + int *val2, long mask)
>>> +{
>>> + struct rpr0521_data *data = iio_priv(indio_dev);
>>> + int ret;
>>> + u8 device_mask;
>>> + __le16 raw_data;
>>> +
>>> + switch (mask) {
>>> + case IIO_CHAN_INFO_RAW:
>>> + if (chan->type != IIO_INTENSITY && chan->type != IIO_PROXIMITY)
>>> + return -EINVAL;
>>> +
>>> + device_mask = rpr0521_data_reg[chan->address].device_mask;
>>> +
>>> + mutex_lock(&data->lock);
>>> + ret = rpr0521_set_power_state(data, true, device_mask);
>>> + if (ret < 0) {
>> Fine as is, but perhaps you would have been better pulling this section
>> out to a separate function then using the traditional goto type error
>> handling to undo the relevant elements as you go rather than having repeats
>> of this mutex unlock for example. Not quite a complex enough case for
>> me to insist on it here though :)
>>> + mutex_unlock(&data->lock);
>>> + return ret;
>
> I see, it seems ok as it is. I'll try to see if using goto makes code easier
> to read.
>
> thanks,
> Daniel.
>