From b897f6db3ae2cd9a42377f8b1865450f34ceff0e Mon Sep 17 00:00:00 2001 From: Benjamin Tissoires Date: Fri, 25 Nov 2016 14:27:22 +0100 Subject: [PATCH] HID: multitouch: do not retrieve all reports for all devices We already have in place a quirk for Windows 8 devices, but it looks like the Surface Cover are not conforming to it. Given that we are only interested in 3 feature reports (the ones that the Windows driver retrieves), we should be safe to unconditionally apply the quirk to everybody. In case there is an issue with a controller, we can always mark it as such in the transport driver, and hid-multitouch won't try to retrieve the feature report. Signed-off-by: Benjamin Tissoires Signed-off-by: Jiri Kosina --- drivers/hid/hid-multitouch.c | 76 +++++++++++++++++++----------------- 1 file changed, 40 insertions(+), 36 deletions(-) diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c index 84c56e645fe8..89e9032ab1e7 100644 --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -108,6 +108,7 @@ struct mt_device { int cc_value_index; /* contact count value index in the field */ unsigned last_slot_field; /* the last field of a slot */ unsigned mt_report_id; /* the report ID of the multitouch device */ + unsigned long initial_quirks; /* initial quirks state */ __s16 inputmode; /* InputMode HID feature, -1 if non-existent */ __s16 inputmode_index; /* InputMode HID feature index in the report */ __s16 maxcontact_report_id; /* Maximum Contact Number HID feature, @@ -318,13 +319,10 @@ static void mt_get_feature(struct hid_device *hdev, struct hid_report *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. + * Do not fetch the feature report if the device has been explicitly + * marked as non-capable. */ - if (!(hdev->quirks & HID_QUIRK_NO_INIT_REPORTS)) - return; - if (td->mtclass.name != MT_CLS_WIN_8) + if (td->initial_quirks & HID_QUIRK_NO_INIT_REPORTS) return; buf = hid_alloc_report_buf(report, GFP_KERNEL); @@ -1085,36 +1083,6 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id) } } - /* This allows the driver to correctly support devices - * that emit events over several HID messages. - */ - hdev->quirks |= HID_QUIRK_NO_INPUT_SYNC; - - /* - * This allows the driver to handle different input sensors - * that emits events through different reports on the same HID - * device. - */ - hdev->quirks |= HID_QUIRK_MULTI_INPUT; - hdev->quirks |= HID_QUIRK_NO_EMPTY_INPUT; - - /* - * Handle special quirks for Windows 8 certified devices. - */ - if (id->group == HID_GROUP_MULTITOUCH_WIN_8) - /* - * Some multitouch screens do not like to be polled for input - * 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_REPORTS; - td = devm_kzalloc(&hdev->dev, sizeof(struct mt_device), GFP_KERNEL); if (!td) { dev_err(&hdev->dev, "cannot allocate multitouch data\n"); @@ -1138,6 +1106,39 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id) if (id->vendor == HID_ANY_ID && id->product == HID_ANY_ID) td->serial_maybe = true; + /* + * Store the initial quirk state + */ + td->initial_quirks = hdev->quirks; + + /* This allows the driver to correctly support devices + * that emit events over several HID messages. + */ + hdev->quirks |= HID_QUIRK_NO_INPUT_SYNC; + + /* + * This allows the driver to handle different input sensors + * that emits events through different reports on the same HID + * device. + */ + hdev->quirks |= HID_QUIRK_MULTI_INPUT; + hdev->quirks |= HID_QUIRK_NO_EMPTY_INPUT; + + /* + * Some multitouch screens do not like to be polled for input + * reports. Fortunately, the Win8 spec says that all touches + * should be sent during each report, making the initialization + * of input reports unnecessary. For Win7 devices, well, let's hope + * they will still be happy (this is only be a problem if a touch + * was already there while probing the device). + * + * 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_REPORTS; + ret = hid_parse(hdev); if (ret != 0) return ret; @@ -1206,8 +1207,11 @@ static int mt_resume(struct hid_device *hdev) static void mt_remove(struct hid_device *hdev) { + struct mt_device *td = hid_get_drvdata(hdev); + sysfs_remove_group(&hdev->dev.kobj, &mt_attribute_group); hid_hw_stop(hdev); + hdev->quirks = td->initial_quirks; } /* -- 2.39.5