[PATCH 1/4] HID: hid-sensor-hub: Enhance feature report API
From: Srinivas Pandruvada <hidden>
Date: 2015-01-07 18:31:45
Also in:
linux-iio
Subsystem:
hid core layer, hid sensor hub drivers, the rest · Maintainers:
Jiri Kosina, Benjamin Tissoires, Jonathan Cameron, Srinivas Pandruvada, Linus Torvalds
Possibly related (same subject, not in this thread)
- 2015-01-07 · [PATCH 1/4] HID: hid-sensor-hub: Enhance feature report API · Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Some hid sensor feature report can contain more than one reports. This API can now support receiving multiple values from the feature report. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada-VuQAYsv1563Yd54FQh9/CA@public.gmane.org> --- drivers/hid/hid-sensor-hub.c | 16 ++++++++++++++-- include/linux/hid-sensor-hub.h | 8 +++++--- 2 files changed, 19 insertions(+), 5 deletions(-)
diff --git a/drivers/hid/hid-sensor-hub.c b/drivers/hid/hid-sensor-hub.c
index 83b6e15..d17aa67 100644
--- a/drivers/hid/hid-sensor-hub.c
+++ b/drivers/hid/hid-sensor-hub.c@@ -218,10 +218,11 @@ done_proc: EXPORT_SYMBOL_GPL(sensor_hub_set_feature); int sensor_hub_get_feature(struct hid_sensor_hub_device *hsdev, u32 report_id, - u32 field_index, s32 *value) + u32 field_index, int buffer_size, void *buffer) { struct hid_report *report; struct sensor_hub_data *data = hid_get_drvdata(hsdev->hdev); + int report_size; int ret = 0; mutex_lock(&data->mutex);
@@ -233,7 +234,18 @@ int sensor_hub_get_feature(struct hid_sensor_hub_device *hsdev, u32 report_id, } hid_hw_request(hsdev->hdev, report, HID_REQ_GET_REPORT); hid_hw_wait(hsdev->hdev); - *value = report->field[field_index]->value[0]; + + /* calculate number of bytes required to read this field */ + report_size = report->field[field_index]->report_size / 8; + if (report->field[field_index]->report_size % 8) + ++report_size; + report_size *= report->field[field_index]->report_count; + if (!report_size) { + ret = -EINVAL; + goto done_proc; + } + ret = min(report_size, buffer_size); + memcpy(buffer, report->field[field_index]->value, ret); done_proc: mutex_unlock(&data->mutex);
diff --git a/include/linux/hid-sensor-hub.h b/include/linux/hid-sensor-hub.h
index 0b21c4f..1995bbd 100644
--- a/include/linux/hid-sensor-hub.h
+++ b/include/linux/hid-sensor-hub.h@@ -203,13 +203,15 @@ int sensor_hub_set_feature(struct hid_sensor_hub_device *hsdev, u32 report_id, * @hsdev: Hub device instance. * @report_id: Report id to look for * @field_index: Field index inside a report -* @value: Place holder for return value +* @buffer_size: size of the buffer +* @buffer: buffer to copy output * * Used to get a field in feature report. For example this can get polling -* interval, sensitivity, activate/deactivate state. +* interval, sensitivity, activate/deactivate state. On success it returns +* number of bytes copied to buffer. On failure, it returns value < 0. */ int sensor_hub_get_feature(struct hid_sensor_hub_device *hsdev, u32 report_id, - u32 field_index, s32 *value); + u32 field_index, int buffer_size, void *buffer); /* hid-sensor-attributes */
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1.9.3