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author | Gwendal Grignou <gwendal@chromium.org> | 2020-03-27 23:34:34 +0100 |
---|---|---|
committer | Enric Balletbo i Serra <enric.balletbo@collabora.com> | 2020-03-28 22:04:32 +0100 |
commit | b9b05664ebf6cd58d2a7f9a7cffa119f331114e6 (patch) | |
tree | 2e178f56b446ec79ea78e01aa776c6644f4f50b3 /drivers/platform/chrome | |
parent | platform/chrome: cros_ec_sensorhub: Add FIFO support (diff) | |
download | linux-b9b05664ebf6cd58d2a7f9a7cffa119f331114e6.tar.xz linux-b9b05664ebf6cd58d2a7f9a7cffa119f331114e6.zip |
platform/chrome: cros_ec_sensorhub: Add code to spread timestmap
EC FIFO can send sensor events in batch. Spread them based on
previous (TSa) and currnet timestamp (TSb)
EC FIFO iio events
+-----------+
| TSa |
+-----------+ +---------------------------------------+
| event 1 | | event 1 | TSb - (TSb - TSa)/n * (n-1) |
+-----------+ +---------------------------------------+
| event 2 | | event 2 | TSb - (TSb - TSa)/n * (n-2) |
+-----------+ +---------------------------------------+
| ... | ------> | .... | |
+-----------+ +---------------------------------------+
| event n-1 | | event 2 | TSb - (TSb - TSa)/n |
+-----------+ +---------------------------------------+
| event n | | event 2 | TSb |
+-----------+ +---------------------------------------+
| TSb |
+-----------+
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Diffstat (limited to 'drivers/platform/chrome')
-rw-r--r-- | drivers/platform/chrome/cros_ec_sensorhub_ring.c | 117 |
1 files changed, 109 insertions, 8 deletions
diff --git a/drivers/platform/chrome/cros_ec_sensorhub_ring.c b/drivers/platform/chrome/cros_ec_sensorhub_ring.c index da73757529ca..443db8277d2b 100644 --- a/drivers/platform/chrome/cros_ec_sensorhub_ring.c +++ b/drivers/platform/chrome/cros_ec_sensorhub_ring.c @@ -190,6 +190,101 @@ cros_ec_sensor_ring_process_event(struct cros_ec_sensorhub *sensorhub, return true; } +/* + * cros_ec_sensor_ring_spread_add: Calculate proper timestamps then add to + * ringbuffer. + * + * If there is a sample with a proper timestamp + * + * timestamp | count + * ----------------- + * older_unprocess_out --> TS1 | 1 + * TS1 | 2 + * out --> TS1 | 3 + * next_out --> TS2 | + * + * We spread time for the samples [older_unprocess_out .. out] + * between TS1 and TS2: [TS1+1/4, TS1+2/4, TS1+3/4, TS2]. + * + * If we reach the end of the samples, we compare with the + * current timestamp: + * + * older_unprocess_out --> TS1 | 1 + * TS1 | 2 + * out --> TS1 | 3 + * + * We know have [TS1+1/3, TS1+2/3, current timestamp] + */ +static void cros_ec_sensor_ring_spread_add(struct cros_ec_sensorhub *sensorhub, + unsigned long sensor_mask, + s64 current_timestamp, + struct cros_ec_sensors_ring_sample + *last_out) +{ + struct cros_ec_sensors_ring_sample *out; + int i; + + for_each_set_bit(i, &sensor_mask, sensorhub->sensor_num) { + s64 older_timestamp; + s64 timestamp; + struct cros_ec_sensors_ring_sample *older_unprocess_out = + sensorhub->ring; + struct cros_ec_sensors_ring_sample *next_out; + int count = 1; + + for (out = sensorhub->ring; out < last_out; out = next_out) { + s64 time_period; + + next_out = out + 1; + if (out->sensor_id != i) + continue; + + /* Timestamp to start with */ + older_timestamp = out->timestamp; + + /* Find next sample. */ + while (next_out < last_out && next_out->sensor_id != i) + next_out++; + + if (next_out >= last_out) { + timestamp = current_timestamp; + } else { + timestamp = next_out->timestamp; + if (timestamp == older_timestamp) { + count++; + continue; + } + } + + /* + * The next sample has a new timestamp, spread the + * unprocessed samples. + */ + if (next_out < last_out) + count++; + time_period = div_s64(timestamp - older_timestamp, + count); + + for (; older_unprocess_out <= out; + older_unprocess_out++) { + if (older_unprocess_out->sensor_id != i) + continue; + older_timestamp += time_period; + older_unprocess_out->timestamp = + older_timestamp; + } + count = 1; + /* The next_out sample has a valid timestamp, skip. */ + next_out++; + older_unprocess_out = next_out; + } + } + + /* Push the event into the kfifo */ + for (out = sensorhub->ring; out < last_out; out++) + cros_sensorhub_send_sample(sensorhub, out); +} + /** * cros_ec_sensorhub_ring_handler() - The trigger handler function * @@ -204,6 +299,7 @@ static void cros_ec_sensorhub_ring_handler(struct cros_ec_sensorhub *sensorhub) struct cros_ec_dev *ec = sensorhub->ec; ktime_t fifo_timestamp, current_timestamp; int i, j, number_data, ret; + unsigned long sensor_mask = 0; struct ec_response_motion_sensor_data *in; struct cros_ec_sensors_ring_sample *out, *last_out; @@ -289,8 +385,10 @@ static void cros_ec_sensorhub_ring_handler(struct cros_ec_sensorhub *sensorhub) sensorhub, fifo_info, fifo_timestamp, ¤t_timestamp, - in, out)) + in, out)) { + sensor_mask |= BIT(in->sensor_num); out++; + } } } mutex_unlock(&sensorhub->cmd_lock); @@ -301,10 +399,10 @@ static void cros_ec_sensorhub_ring_handler(struct cros_ec_sensorhub *sensorhub) goto ring_handler_end; /* - * Check if current_timestamp is ahead of the last sample. - * Normally, the EC appends a timestamp after the last sample, but if - * the AP is slow to respond to the IRQ, the EC may have added new - * samples. Use the FIFO info timestamp as last timestamp then. + * Check if current_timestamp is ahead of the last sample. Normally, + * the EC appends a timestamp after the last sample, but if the AP + * is slow to respond to the IRQ, the EC may have added new samples. + * Use the FIFO info timestamp as last timestamp then. */ if ((last_out - 1)->timestamp == current_timestamp) current_timestamp = fifo_timestamp; @@ -319,9 +417,12 @@ static void cros_ec_sensorhub_ring_handler(struct cros_ec_sensorhub *sensorhub) fifo_info->total_lost); } - /* Push the event into the FIFO. */ - for (out = sensorhub->ring; out < last_out; out++) - cros_sensorhub_send_sample(sensorhub, out); + /* + * Spread samples in case of batching, then add them to the + * ringbuffer. + */ + cros_ec_sensor_ring_spread_add(sensorhub, sensor_mask, + current_timestamp, last_out); ring_handler_end: sensorhub->fifo_timestamp[CROS_EC_SENSOR_LAST_TS] = current_timestamp; |