Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754219Ab2FSNG5 (ORCPT ); Tue, 19 Jun 2012 09:06:57 -0400 Received: from mail-wi0-f172.google.com ([209.85.212.172]:53940 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752209Ab2FSNG4 (ORCPT ); Tue, 19 Jun 2012 09:06:56 -0400 From: "benjamin.tissoires" To: "benjamin.tissoires" , Dmitry Torokhov , Henrik Rydberg , Jiri Kosina , Stephane Chatty , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH Stable 3.4.x] HID: hid-multitouch: fix wrong protocol detection Date: Tue, 19 Jun 2012 15:06:46 +0200 Message-Id: <1340111206-11659-1-git-send-email-benjamin.tissoires@gmail.com> X-Mailer: git-send-email 1.7.10.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6647 Lines: 201 From: Benjamin Tissoires The previous implementation introduced a randomness in the splitting of the different touches reported by the device. This version is more robust as we don't rely on hi->input->absbit, but on our own structure. This also prepares hid-multitouch to better support Win8 devices. [commit 3ac36d15557d1bedfb1151d9911b9587b2d40759 in Linus' tree] Signed-off-by: Benjamin Tissoires --- Hi Jiri, This patch is a port of the one included in the future 3.5. I already had users complaining about the broken behavior in 3.4, then this respin for 3.4. Kernels 3.3 and below are not impacted by the bug. Cheers, Benjamin drivers/hid/hid-multitouch.c | 58 +++++++++++++++++++++++++++++++++--------- 1 file changed, 46 insertions(+), 12 deletions(-) diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c index 1d5b941..543896d 100644 --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -70,9 +70,16 @@ struct mt_class { bool is_indirect; /* true for touchpads */ }; +struct mt_fields { + unsigned usages[HID_MAX_FIELDS]; + unsigned int length; +}; + struct mt_device { struct mt_slot curdata; /* placeholder of incoming data */ struct mt_class mtclass; /* our mt device class */ + struct mt_fields *fields; /* temporary placeholder for storing the + multitouch fields */ unsigned last_field_index; /* last field index of the report */ unsigned last_slot_field; /* the last field of a slot */ __s8 inputmode; /* InputMode HID feature, -1 if non-existent */ @@ -275,11 +282,15 @@ static void set_abs(struct input_dev *input, unsigned int code, input_set_abs_params(input, code, fmin, fmax, fuzz, 0); } -static void set_last_slot_field(struct hid_usage *usage, struct mt_device *td, +static void mt_store_field(struct hid_usage *usage, struct mt_device *td, struct hid_input *hi) { - if (!test_bit(usage->hid, hi->input->absbit)) - td->last_slot_field = usage->hid; + struct mt_fields *f = td->fields; + + if (f->length >= HID_MAX_FIELDS) + return; + + f->usages[f->length++] = usage->hid; } static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi, @@ -330,7 +341,7 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi, cls->sn_move); /* touchscreen emulation */ set_abs(hi->input, ABS_X, field, cls->sn_move); - set_last_slot_field(usage, td, hi); + mt_store_field(usage, td, hi); td->last_field_index = field->index; return 1; case HID_GD_Y: @@ -340,7 +351,7 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi, cls->sn_move); /* touchscreen emulation */ set_abs(hi->input, ABS_Y, field, cls->sn_move); - set_last_slot_field(usage, td, hi); + mt_store_field(usage, td, hi); td->last_field_index = field->index; return 1; } @@ -349,24 +360,24 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi, case HID_UP_DIGITIZER: switch (usage->hid) { case HID_DG_INRANGE: - set_last_slot_field(usage, td, hi); + mt_store_field(usage, td, hi); td->last_field_index = field->index; return 1; case HID_DG_CONFIDENCE: - set_last_slot_field(usage, td, hi); + mt_store_field(usage, td, hi); td->last_field_index = field->index; return 1; case HID_DG_TIPSWITCH: hid_map_usage(hi, usage, bit, max, EV_KEY, BTN_TOUCH); input_set_capability(hi->input, EV_KEY, BTN_TOUCH); - set_last_slot_field(usage, td, hi); + mt_store_field(usage, td, hi); td->last_field_index = field->index; return 1; case HID_DG_CONTACTID: if (!td->maxcontacts) td->maxcontacts = MT_DEFAULT_MAXCONTACT; input_mt_init_slots(hi->input, td->maxcontacts); - td->last_slot_field = usage->hid; + mt_store_field(usage, td, hi); td->last_field_index = field->index; td->touches_by_report++; return 1; @@ -375,7 +386,7 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi, EV_ABS, ABS_MT_TOUCH_MAJOR); set_abs(hi->input, ABS_MT_TOUCH_MAJOR, field, cls->sn_width); - set_last_slot_field(usage, td, hi); + mt_store_field(usage, td, hi); td->last_field_index = field->index; return 1; case HID_DG_HEIGHT: @@ -385,7 +396,7 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi, cls->sn_height); input_set_abs_params(hi->input, ABS_MT_ORIENTATION, 0, 1, 0, 0); - set_last_slot_field(usage, td, hi); + mt_store_field(usage, td, hi); td->last_field_index = field->index; return 1; case HID_DG_TIPPRESSURE: @@ -396,7 +407,7 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi, /* touchscreen emulation */ set_abs(hi->input, ABS_PRESSURE, field, cls->sn_pressure); - set_last_slot_field(usage, td, hi); + mt_store_field(usage, td, hi); td->last_field_index = field->index; return 1; case HID_DG_CONTACTCOUNT: @@ -635,6 +646,16 @@ static void mt_set_maxcontacts(struct hid_device *hdev) } } +static void mt_post_parse(struct mt_device *td) +{ + struct mt_fields *f = td->fields; + + if (td->touches_by_report > 0) { + int field_count_per_touch = f->length / td->touches_by_report; + td->last_slot_field = f->usages[field_count_per_touch - 1]; + } +} + static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id) { int ret, i; @@ -666,6 +687,13 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id) td->maxcontact_report_id = -1; hid_set_drvdata(hdev, td); + td->fields = kzalloc(sizeof(struct mt_fields), GFP_KERNEL); + if (!td->fields) { + dev_err(&hdev->dev, "cannot allocate multitouch fields data\n"); + ret = -ENOMEM; + goto fail; + } + ret = hid_parse(hdev); if (ret != 0) goto fail; @@ -674,6 +702,8 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id) if (ret) goto fail; + mt_post_parse(td); + if (!id && td->touches_by_report == 1) { /* the device has been sent by hid-generic */ mtclass = &td->mtclass; @@ -697,9 +727,13 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id) mt_set_maxcontacts(hdev); mt_set_input_mode(hdev); + kfree(td->fields); + td->fields = NULL; + return 0; fail: + kfree(td->fields); kfree(td); return ret; } -- 1.7.10.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/