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@xxxxxxxxxx> Cc: Jonathan Cameron <jic23@xxxxxxxxxx> Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx> --- * Changes from v1 (addressed comment from Peter Meerwald) - Neaten the special function code notation - Improve the code comment for tcs3472_intr_pers[] - Fix error path with invalid event info in write_event_value() - Handle correctly if the negative period time is specified (round to the minimum available period time) - Remove redundant the PERS register write - Call free_irq() in reverse order of the initialization. drivers/iio/light/tcs3472.c | 262 ++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 254 insertions(+), 8 deletions(-) diff --git a/drivers/iio/light/tcs3472.c b/drivers/iio/light/tcs3472.c index 09e6ca5..e1c8a07 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, .driver_module = THIS_MODULE, }; @@ -263,6 +456,7 @@ 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; @@ -292,12 +486,29 @@ 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) @@ -308,12 +519,24 @@ 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; @@ -321,8 +544,19 @@ 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) @@ -330,6 +564,7 @@ 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)); @@ -348,8 +583,19 @@ 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 -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
