diff options
-rw-r--r-- | drivers/hid/hid-multitouch.c | 45 |
1 files changed, 44 insertions, 1 deletions
diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c index 661b4fce1a5d..dd64461e5e85 100644 --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -309,6 +309,41 @@ static struct attribute_group mt_attribute_group = { .attrs = sysfs_attrs }; +static void mt_get_feature(struct hid_device *hdev, struct hid_report *report) +{ + struct mt_device *td = hid_get_drvdata(hdev); + int ret, size = hid_report_len(report); + u8 *buf; + + /* + * Only fetch the feature report if initial reports are not already + * been retrieved. Currently this is only done for Windows 8 touch + * devices. + */ + if (!(hdev->quirks & HID_QUIRK_NO_INIT_REPORTS)) + return; + if (td->mtclass.name != MT_CLS_WIN_8) + return; + + buf = hid_alloc_report_buf(report, GFP_KERNEL); + if (!buf) + return; + + ret = hid_hw_raw_request(hdev, report->id, buf, size, + HID_FEATURE_REPORT, HID_REQ_GET_REPORT); + if (ret < 0) { + dev_warn(&hdev->dev, "failed to fetch feature %d\n", + report->id); + } else { + ret = hid_report_raw_event(hdev, HID_FEATURE_REPORT, buf, + size, 0); + if (ret) + dev_warn(&hdev->dev, "failed to report feature\n"); + } + + kfree(buf); +} + static void mt_feature_mapping(struct hid_device *hdev, struct hid_field *field, struct hid_usage *usage) { @@ -327,6 +362,8 @@ static void mt_feature_mapping(struct hid_device *hdev, break; case HID_DG_CONTACTMAX: + mt_get_feature(hdev, field->report); + td->maxcontact_report_id = field->report->id; td->maxcontacts = field->value[0]; if (!td->maxcontacts && @@ -343,6 +380,7 @@ static void mt_feature_mapping(struct hid_device *hdev, break; } + mt_get_feature(hdev, field->report); if (field->value[usage->usage_index] == MT_BUTTONTYPE_CLICKPAD) td->is_buttonpad = true; @@ -1029,8 +1067,13 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id) * reports. Fortunately, the Win8 spec says that all touches * should be sent during each report, making the initialization * of input reports unnecessary. + * + * In addition some touchpads do not behave well if we read + * all feature reports from them. Instead we prevent + * initial report fetching and then selectively fetch each + * report we are interested in. */ - hdev->quirks |= HID_QUIRK_NO_INIT_INPUT_REPORTS; + hdev->quirks |= HID_QUIRK_NO_INIT_REPORTS; td = devm_kzalloc(&hdev->dev, sizeof(struct mt_device), GFP_KERNEL); if (!td) { |