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iio: light: tcs3472: support out-of-threshold events

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The TCS3472 device provides interrupt signal for out-of-threshold events
with persistence filter.

This change adds interrupt support for the threshold events and enables
to configure the period of time by persistence filter.

Cc: Peter Meerwald <pmeerw@pmeerw.net>
Cc: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Akinobu Mita 2017-06-27 00:44:55 +09:00 committed by Jonathan Cameron
parent 1405ddfbf1
commit 9d2f715d59
1 changed files with 254 additions and 8 deletions
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262
drivers/iio/light/tcs3472.c
View file

@ -13,7 +13,7 @@
*
* Datasheet: http://ams.com/eng/content/download/319364/1117183/file/TCS3472_Datasheet_EN_v2.pdf
*
* TODO: interrupt support, thresholds, wait time
* TODO: wait time
*/
#include <linux/module.h>
@ -23,6 +23,7 @@
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/events.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/buffer.h>
#include <linux/iio/triggered_buffer.h>
@ -31,12 +32,15 @@
#define TCS3472_COMMAND BIT(7)
#define TCS3472_AUTO_INCR BIT(5)
#define TCS3472_SPECIAL_FUNC (BIT(5) | BIT(6))
#define TCS3472_INTR_CLEAR (TCS3472_COMMAND | TCS3472_SPECIAL_FUNC | 0x06)
#define TCS3472_ENABLE (TCS3472_COMMAND | 0x00)
#define TCS3472_ATIME (TCS3472_COMMAND | 0x01)
#define TCS3472_WTIME (TCS3472_COMMAND | 0x03)
#define TCS3472_AILT (TCS3472_COMMAND | 0x04)
#define TCS3472_AIHT (TCS3472_COMMAND | 0x06)
#define TCS3472_AILT (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x04)
#define TCS3472_AIHT (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x06)
#define TCS3472_PERS (TCS3472_COMMAND | 0x0c)
#define TCS3472_CONFIG (TCS3472_COMMAND | 0x0d)
#define TCS3472_CONTROL (TCS3472_COMMAND | 0x0f)
@ -47,19 +51,42 @@
#define TCS3472_GDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x18)
#define TCS3472_BDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x1a)
#define TCS3472_STATUS_AINT BIT(4)
#define TCS3472_STATUS_AVALID BIT(0)
#define TCS3472_ENABLE_AIEN BIT(4)
#define TCS3472_ENABLE_AEN BIT(1)
#define TCS3472_ENABLE_PON BIT(0)
#define TCS3472_CONTROL_AGAIN_MASK (BIT(0) | BIT(1))
struct tcs3472_data {
struct i2c_client *client;
struct mutex lock;
u16 low_thresh;
u16 high_thresh;
u8 enable;
u8 control;
u8 atime;
u8 apers;
u16 buffer[8]; /* 4 16-bit channels + 64-bit timestamp */
};
static const struct iio_event_spec tcs3472_events[] = {
{
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_RISING,
.mask_separate = BIT(IIO_EV_INFO_VALUE),
}, {
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_FALLING,
.mask_separate = BIT(IIO_EV_INFO_VALUE),
}, {
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_EITHER,
.mask_separate = BIT(IIO_EV_INFO_ENABLE) |
BIT(IIO_EV_INFO_PERIOD),
},
};
#define TCS3472_CHANNEL(_color, _si, _addr) { \
.type = IIO_INTENSITY, \
.modified = 1, \
@ -75,6 +102,8 @@ struct tcs3472_data {
.storagebits = 16, \
.endianness = IIO_CPU, \
}, \
.event_spec = _si ? NULL : tcs3472_events, \
.num_event_specs = _si ? 0 : ARRAY_SIZE(tcs3472_events), \
}
static const int tcs3472_agains[] = { 1, 4, 16, 60 };
@ -182,6 +211,166 @@ static int tcs3472_write_raw(struct iio_dev *indio_dev,
return -EINVAL;
}
/*
* Translation from APERS field value to the number of consecutive out-of-range
* clear channel values before an interrupt is generated
*/
static const int tcs3472_intr_pers[] = {
0, 1, 2, 3, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60
};
static int tcs3472_read_event(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan, enum iio_event_type type,
enum iio_event_direction dir, enum iio_event_info info, int *val,
int *val2)
{
struct tcs3472_data *data = iio_priv(indio_dev);
int ret;
unsigned int period;
mutex_lock(&data->lock);
switch (info) {
case IIO_EV_INFO_VALUE:
*val = (dir == IIO_EV_DIR_RISING) ?
data->high_thresh : data->low_thresh;
ret = IIO_VAL_INT;
break;
case IIO_EV_INFO_PERIOD:
period = (256 - data->atime) * 2400 *
tcs3472_intr_pers[data->apers];
*val = period / USEC_PER_SEC;
*val2 = period % USEC_PER_SEC;
ret = IIO_VAL_INT_PLUS_MICRO;
break;
default:
ret = -EINVAL;
break;
}
mutex_unlock(&data->lock);
return ret;
}
static int tcs3472_write_event(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan, enum iio_event_type type,
enum iio_event_direction dir, enum iio_event_info info, int val,
int val2)
{
struct tcs3472_data *data = iio_priv(indio_dev);
int ret;
u8 command;
int period;
int i;
mutex_lock(&data->lock);
switch (info) {
case IIO_EV_INFO_VALUE:
switch (dir) {
case IIO_EV_DIR_RISING:
command = TCS3472_AIHT;
break;
case IIO_EV_DIR_FALLING:
command = TCS3472_AILT;
break;
default:
ret = -EINVAL;
goto error;
}
ret = i2c_smbus_write_word_data(data->client, command, val);
if (ret)
goto error;
if (dir == IIO_EV_DIR_RISING)
data->high_thresh = val;
else
data->low_thresh = val;
break;
case IIO_EV_INFO_PERIOD:
period = val * USEC_PER_SEC + val2;
for (i = 1; i < ARRAY_SIZE(tcs3472_intr_pers) - 1; i++) {
if (period <= (256 - data->atime) * 2400 *
tcs3472_intr_pers[i])
break;
}
ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS, i);
if (ret)
goto error;
data->apers = i;
break;
default:
ret = -EINVAL;
break;
}
error:
mutex_unlock(&data->lock);
return ret;
}
static int tcs3472_read_event_config(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan, enum iio_event_type type,
enum iio_event_direction dir)
{
struct tcs3472_data *data = iio_priv(indio_dev);
int ret;
mutex_lock(&data->lock);
ret = !!(data->enable & TCS3472_ENABLE_AIEN);
mutex_unlock(&data->lock);
return ret;
}
static int tcs3472_write_event_config(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan, enum iio_event_type type,
enum iio_event_direction dir, int state)
{
struct tcs3472_data *data = iio_priv(indio_dev);
int ret = 0;
u8 enable_old;
mutex_lock(&data->lock);
enable_old = data->enable;
if (state)
data->enable |= TCS3472_ENABLE_AIEN;
else
data->enable &= ~TCS3472_ENABLE_AIEN;
if (enable_old != data->enable) {
ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
data->enable);
if (ret)
data->enable = enable_old;
}
mutex_unlock(&data->lock);
return ret;
}
static irqreturn_t tcs3472_event_handler(int irq, void *priv)
{
struct iio_dev *indio_dev = priv;
struct tcs3472_data *data = iio_priv(indio_dev);
int ret;
ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS);
if (ret >= 0 && (ret & TCS3472_STATUS_AINT)) {
iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0,
IIO_EV_TYPE_THRESH,
IIO_EV_DIR_EITHER),
iio_get_time_ns(indio_dev));
i2c_smbus_read_byte_data(data->client, TCS3472_INTR_CLEAR);
}
return IRQ_HANDLED;
}
static irqreturn_t tcs3472_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
@ -245,6 +434,10 @@ static const struct attribute_group tcs3472_attribute_group = {
static const struct iio_info tcs3472_info = {
.read_raw = tcs3472_read_raw,
.write_raw = tcs3472_write_raw,
.read_event_value = tcs3472_read_event,
.write_event_value = tcs3472_write_event,
.read_event_config = tcs3472_read_event_config,
.write_event_config = tcs3472_write_event_config,
.attrs = &tcs3472_attribute_group,
};
@ -262,6 +455,7 @@ static int tcs3472_probe(struct i2c_client *client,
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 = &tcs3472_info;
@ -291,12 +485,29 @@ static int tcs3472_probe(struct i2c_client *client,
return ret;
data->atime = ret;
ret = i2c_smbus_read_word_data(data->client, TCS3472_AILT);
if (ret < 0)
return ret;
data->low_thresh = ret;
ret = i2c_smbus_read_word_data(data->client, TCS3472_AIHT);
if (ret < 0)
return ret;
data->high_thresh = ret;
data->apers = 1;
ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS,
data->apers);
if (ret < 0)
return ret;
ret = i2c_smbus_read_byte_data(data->client, TCS3472_ENABLE);
if (ret < 0)
return ret;
/* enable device */
data->enable = ret | TCS3472_ENABLE_PON | TCS3472_ENABLE_AEN;
data->enable &= ~TCS3472_ENABLE_AIEN;
ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
data->enable);
if (ret < 0)
@ -307,12 +518,24 @@ static int tcs3472_probe(struct i2c_client *client,
if (ret < 0)
return ret;
if (client->irq) {
ret = request_threaded_irq(client->irq, NULL,
tcs3472_event_handler,
IRQF_TRIGGER_FALLING | IRQF_SHARED |
IRQF_ONESHOT,
client->name, indio_dev);
if (ret)
goto buffer_cleanup;
}
ret = iio_device_register(indio_dev);
if (ret < 0)
goto buffer_cleanup;
goto free_irq;
return 0;
free_irq:
free_irq(client->irq, indio_dev);
buffer_cleanup:
iio_triggered_buffer_cleanup(indio_dev);
return ret;
@ -320,8 +543,19 @@ static int tcs3472_probe(struct i2c_client *client,
static int tcs3472_powerdown(struct tcs3472_data *data)
{
return i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
data->enable & ~(TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON));
int ret;
u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON;
mutex_lock(&data->lock);
ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
data->enable & ~enable_mask);
if (!ret)
data->enable &= ~enable_mask;
mutex_unlock(&data->lock);
return ret;
}
static int tcs3472_remove(struct i2c_client *client)
@ -329,6 +563,7 @@ static int tcs3472_remove(struct i2c_client *client)
struct iio_dev *indio_dev = i2c_get_clientdata(client);
iio_device_unregister(indio_dev);
free_irq(client->irq, indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
tcs3472_powerdown(iio_priv(indio_dev));
@ -347,8 +582,19 @@ static int tcs3472_resume(struct device *dev)
{
struct tcs3472_data *data = iio_priv(i2c_get_clientdata(
to_i2c_client(dev)));
return i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
data->enable | (TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON));
int ret;
u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON;
mutex_lock(&data->lock);
ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
data->enable | enable_mask);
if (!ret)
data->enable |= enable_mask;
mutex_unlock(&data->lock);
return ret;
}
#endif