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authorAkinobu Mita <akinobu.mita@gmail.com>2017-06-27 00:44:55 +0900
committerJonathan Cameron <Jonathan.Cameron@huawei.com>2017-09-03 18:10:29 +0100
commit9d2f715d592eb4d0e643f6219f4a160fbd62934d (patch)
tree7d774a3969173058fc13fef05672ad9d92fc3c0f /drivers/iio/light
parent1405ddfbf10a4e3475babf533fca5f5f60dba2c8 (diff)
downloadlinux-9d2f715d592eb4d0e643f6219f4a160fbd62934d.tar.bz2
iio: light: tcs3472: support out-of-threshold events
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>
Diffstat (limited to 'drivers/iio/light')
-rw-r--r--drivers/iio/light/tcs3472.c262
1 files changed, 254 insertions, 8 deletions
diff --git a/drivers/iio/light/tcs3472.c b/drivers/iio/light/tcs3472.c
index 9540a5c1d746..e7923b514d7a 100644
--- a/drivers/iio/light/tcs3472.c
+++ b/drivers/iio/light/tcs3472.c
@@ -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 @@ buffer_cleanup:
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