From 138bc7969c24c6cbba28e919c2376ad10a46fc60 Mon Sep 17 00:00:00 2001 From: Srinivas Pandruvada Date: Fri, 7 Apr 2017 19:22:06 -0700 Subject: [PATCH] iio: hid-sensor-hub: Implement batch mode HID sensor hubs using Integrated Senor Hub (ISH) has added capability to support batch mode. This allows host processor to go to sleep for extended duration, while the sensor hub is storing samples in its internal buffers. 'Commit f4f4673b7535 ("iio: add support for hardware fifo")' implements feature in IIO core to implement such feature. This feature is used in bmc150-accel-core.c to implement batch mode. This implementation allows software device buffer watermark to be used as a hint to adjust hardware FIFO. But HID sensor hubs don't allow to change internal buffer size of FIFOs. Instead an additional usage id to set "maximum report latency" is defined. This allows host to go to sleep upto this latency period without getting any report. Since there is no ABI to set this latency, a new attribute "hwfifo_timeout" is added so that user mode can specify a latency. This change checks presence of usage id to get/set maximum report latency and if present, it will expose hwfifo_timeout. Signed-off-by: Srinivas Pandruvada Signed-off-by: Jonathan Cameron --- Documentation/ABI/testing/sysfs-bus-iio | 11 +++ .../hid-sensors/hid-sensor-attributes.c | 44 ++++++++++ .../common/hid-sensors/hid-sensor-trigger.c | 80 +++++++++++++++++++ include/linux/hid-sensor-hub.h | 5 ++ include/linux/hid-sensor-ids.h | 3 + 5 files changed, 143 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio index 8c24d0892f61..2db2cdf42d54 100644 --- a/Documentation/ABI/testing/sysfs-bus-iio +++ b/Documentation/ABI/testing/sysfs-bus-iio @@ -1425,6 +1425,17 @@ Description: guarantees that the hardware fifo is flushed to the device buffer. +What: /sys/bus/iio/devices/iio:device*/buffer/hwfifo_timeout +KernelVersion: 4.12 +Contact: linux-iio@vger.kernel.org +Description: + A read/write property to provide capability to delay reporting of + samples till a timeout is reached. This allows host processors to + sleep, while the sensor is storing samples in its internal fifo. + The maximum timeout in seconds can be specified by setting + hwfifo_timeout.The current delay can be read by reading + hwfifo_timeout. A value of 0 means that there is no timeout. + What: /sys/bus/iio/devices/iio:deviceX/buffer/hwfifo_watermark KernelVersion: 4.2 Contact: linux-iio@vger.kernel.org diff --git a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c index 0e05f6d1e761..f5d4d786e193 100644 --- a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c +++ b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c @@ -410,6 +410,48 @@ int hid_sensor_get_reporting_interval(struct hid_sensor_hub_device *hsdev, } +static void hid_sensor_get_report_latency_info(struct hid_sensor_hub_device *hsdev, + u32 usage_id, + struct hid_sensor_common *st) +{ + sensor_hub_input_get_attribute_info(hsdev, HID_FEATURE_REPORT, + usage_id, + HID_USAGE_SENSOR_PROP_REPORT_LATENCY, + &st->report_latency); + + hid_dbg(hsdev->hdev, "Report latency attributes: %x:%x\n", + st->report_latency.index, st->report_latency.report_id); +} + +int hid_sensor_get_report_latency(struct hid_sensor_common *st) +{ + int ret; + int value; + + ret = sensor_hub_get_feature(st->hsdev, st->report_latency.report_id, + st->report_latency.index, sizeof(value), + &value); + if (ret < 0) + return ret; + + return value; +} +EXPORT_SYMBOL(hid_sensor_get_report_latency); + +int hid_sensor_set_report_latency(struct hid_sensor_common *st, int latency_ms) +{ + return sensor_hub_set_feature(st->hsdev, st->report_latency.report_id, + st->report_latency.index, + sizeof(latency_ms), &latency_ms); +} +EXPORT_SYMBOL(hid_sensor_set_report_latency); + +bool hid_sensor_batch_mode_supported(struct hid_sensor_common *st) +{ + return st->report_latency.index > 0 && st->report_latency.report_id > 0; +} +EXPORT_SYMBOL(hid_sensor_batch_mode_supported); + int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev, u32 usage_id, struct hid_sensor_common *st) @@ -451,6 +493,8 @@ int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev, } else st->timestamp_ns_scale = 1000000000; + hid_sensor_get_report_latency_info(hsdev, usage_id, st); + hid_dbg(hsdev->hdev, "common attributes: %x:%x, %x:%x, %x:%x %x:%x %x:%x\n", st->poll.index, st->poll.report_id, st->report_state.index, st->report_state.report_id, diff --git a/drivers/iio/common/hid-sensors/hid-sensor-trigger.c b/drivers/iio/common/hid-sensors/hid-sensor-trigger.c index 0b5dea050239..16ade0a0327b 100644 --- a/drivers/iio/common/hid-sensors/hid-sensor-trigger.c +++ b/drivers/iio/common/hid-sensors/hid-sensor-trigger.c @@ -26,9 +26,84 @@ #include #include #include +#include #include #include "hid-sensor-trigger.h" +static ssize_t _hid_sensor_set_report_latency(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev); + int integer, fract, ret; + int latency; + + ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract); + if (ret) + return ret; + + latency = integer * 1000 + fract / 1000; + ret = hid_sensor_set_report_latency(attrb, latency); + if (ret < 0) + return len; + + attrb->latency_ms = hid_sensor_get_report_latency(attrb); + + return len; +} + +static ssize_t _hid_sensor_get_report_latency(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev); + int latency; + + latency = hid_sensor_get_report_latency(attrb); + if (latency < 0) + return latency; + + return sprintf(buf, "%d.%06u\n", latency / 1000, (latency % 1000) * 1000); +} + +static ssize_t _hid_sensor_get_fifo_state(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev); + int latency; + + latency = hid_sensor_get_report_latency(attrb); + if (latency < 0) + return latency; + + return sprintf(buf, "%d\n", !!latency); +} + +static IIO_DEVICE_ATTR(hwfifo_timeout, 0644, + _hid_sensor_get_report_latency, + _hid_sensor_set_report_latency, 0); +static IIO_DEVICE_ATTR(hwfifo_enabled, 0444, + _hid_sensor_get_fifo_state, NULL, 0); + +static const struct attribute *hid_sensor_fifo_attributes[] = { + &iio_dev_attr_hwfifo_timeout.dev_attr.attr, + &iio_dev_attr_hwfifo_enabled.dev_attr.attr, + NULL, +}; + +static void hid_sensor_setup_batch_mode(struct iio_dev *indio_dev, + struct hid_sensor_common *st) +{ + if (!hid_sensor_batch_mode_supported(st)) + return; + + iio_buffer_set_attrs(indio_dev->buffer, hid_sensor_fifo_attributes); +} + static int _hid_sensor_power_state(struct hid_sensor_common *st, bool state) { int state_val; @@ -141,6 +216,9 @@ static void hid_sensor_set_power_work(struct work_struct *work) sizeof(attrb->raw_hystersis), &attrb->raw_hystersis); + if (attrb->latency_ms > 0) + hid_sensor_set_report_latency(attrb, attrb->latency_ms); + _hid_sensor_power_state(attrb, true); } @@ -192,6 +270,8 @@ int hid_sensor_setup_trigger(struct iio_dev *indio_dev, const char *name, attrb->trigger = trig; indio_dev->trig = iio_trigger_get(trig); + hid_sensor_setup_batch_mode(indio_dev, attrb); + ret = pm_runtime_set_active(&indio_dev->dev); if (ret) goto error_unreg_trigger; diff --git a/include/linux/hid-sensor-hub.h b/include/linux/hid-sensor-hub.h index f32d7c392c1e..fc7aae64dcde 100644 --- a/include/linux/hid-sensor-hub.h +++ b/include/linux/hid-sensor-hub.h @@ -233,12 +233,14 @@ struct hid_sensor_common { atomic_t user_requested_state; int poll_interval; int raw_hystersis; + int latency_ms; struct iio_trigger *trigger; int timestamp_ns_scale; struct hid_sensor_hub_attribute_info poll; struct hid_sensor_hub_attribute_info report_state; struct hid_sensor_hub_attribute_info power_state; struct hid_sensor_hub_attribute_info sensitivity; + struct hid_sensor_hub_attribute_info report_latency; struct work_struct work; }; @@ -276,5 +278,8 @@ s32 hid_sensor_read_poll_value(struct hid_sensor_common *st); int64_t hid_sensor_convert_timestamp(struct hid_sensor_common *st, int64_t raw_value); +bool hid_sensor_batch_mode_supported(struct hid_sensor_common *st); +int hid_sensor_set_report_latency(struct hid_sensor_common *st, int latency); +int hid_sensor_get_report_latency(struct hid_sensor_common *st); #endif diff --git a/include/linux/hid-sensor-ids.h b/include/linux/hid-sensor-ids.h index 5af62c7e49f3..76033e0420a7 100644 --- a/include/linux/hid-sensor-ids.h +++ b/include/linux/hid-sensor-ids.h @@ -152,6 +152,9 @@ #define HID_USAGE_SENSOR_PROP_REPORT_STATE 0x200316 #define HID_USAGE_SENSOR_PROY_POWER_STATE 0x200319 +/* Batch mode selectors */ +#define HID_USAGE_SENSOR_PROP_REPORT_LATENCY 0x20031B + /* Per data field properties */ #define HID_USAGE_SENSOR_DATA_MOD_NONE 0x00 #define HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS 0x1000