Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759603Ab3HNQAF (ORCPT ); Wed, 14 Aug 2013 12:00:05 -0400 Received: from mga09.intel.com ([134.134.136.24]:14770 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758206Ab3HNQAC (ORCPT ); Wed, 14 Aug 2013 12:00:02 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.89,878,1367996400"; d="scan'208";a="362625373" Message-ID: <520BAB31.2020508@linux.intel.com> Date: Wed, 14 Aug 2013 09:07:13 -0700 From: Srinivas Pandruvada User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130514 Thunderbird/17.0.6 MIME-Version: 1.0 To: Alexander Holler CC: Benjamin Tissoires , Benjamin Tissoires , Henrik Rydberg , Jiri Kosina , Stephane Chatty , Mika Westerberg , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/3] HID: Use existing parser for pre-scanning the report descriptors References: <1376405889-12378-1-git-send-email-benjamin.tissoires@redhat.com> <1376405889-12378-2-git-send-email-benjamin.tissoires@redhat.com> <520A7CDF.3070808@ahsoftware.de> In-Reply-To: <520A7CDF.3070808@ahsoftware.de> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 12293 Lines: 337 On 08/13/2013 11:37 AM, Alexander Holler wrote: > Am 13.08.2013 16:58, schrieb Benjamin Tissoires: >> hid_scan_report() implements its own HID report descriptor parsing. >> It was >> fine until we added the SENSOR_HUB detection. It is going to be even >> worse >> with the detection of Win 8 certified touchscreen, as this detection >> relies on a special feature and on the report_size and report_count >> fields. > > Sorry, but I can't agree with your wording here. > > If you look at the if expression I've added to support HID sensor > hubs, you will notice that the first expression was a test for the > usage page of sensor hubs. That wasn't the first test by accident, > instead I've choosen the order of those 4 tests very carefully to make > the impact on the existing parsing of other HID devices very small. So > it might not have be pleasing to your eyes, but it was for sure an > appropriate solution. > > Anyway, I've tested your patch 1/3 on top of 3.11-rc5 here and the > detection of sensor hubs doesn't work anymore with your patch applied. > Up to now I only had a quick look at it, but it looks like the test in > hid_scan_open_collection() isn't hit for my device. > > Another problem is that I don't have any commercial sensor hub and I'm > therefor not a very relvant as tester (I've implemented the firmware > for my HID (sensor hub) device too). Therefor I've added Srinivas > Pandruvada to cc, because he's the only one I know who has HID sensor > hubs. > Tested on 3.11-rc5. Sensor hubs are no longer detected. If you have some patch to fix this, I can give a try. > And, as said, I've implemented the other side here too, therefor I've > added the descriptor I'm using below. > > Regards, > > Alexander Holler > > > --my-descriptor-- > 0x05, 0x20, // HID_USAGE_PAGE_SENSOR > 0xa1, 0x01, // COLLECTION (Application) > 0x09, 0xa0, // HID_USAGE_SENSOR_CATEGORY_TIME > 0xa1, 0x00, // COLLECTION (Physical) > #ifndef USE_FULL_YEAR > 0x75, 0x08, // REPORT_SIZE (8 bits) > #endif > 0x95, 0x01, // REPORT_COUNT (1) > 0x85, HID_REPORT_ID_TIME, // REPORT_ID > > 0x0a, 0x21, 0x05, // USAGE (Year) > #ifdef USE_FULL_YEAR > 0x75, 0x10, // REPORT_SIZE (16 bits) > #else > 0x15, 0x00, // LOGICAL_MINIMUM (0) (Range is currently not > specified in HUTRR39) > 0x25, 0x63, // LOGICAL_MAXIMUM (99) > #endif > 0x65, 0x00, // UNIT (None) > 0x81, 0x02, // INPUT (Data,Var,Abs) > > 0x0a, 0x22, 0x05, // USAGE (Month) > #ifdef USE_FULL_YEAR > 0x75, 0x08, // REPORT_SIZE (8 bits) > #endif > 0x15, 0x01, // LOGICAL_MINIMUM (1) > 0x25, 0x0c, // LOGICAL_MAXIMUM (12) > 0x65, 0x00, // UNIT (None) > 0x81, 0x02, // INPUT (Data,Var,Abs) > > 0x0a, 0x23, 0x05, // USAGE (Day) > 0x15, 0x01, // LOGICAL_MINIMUM (1) > 0x25, 0x1f, // LOGICAL_MAXIMUM (31) > 0x65, 0x00, // UNIT (None) > 0x81, 0x02, // INPUT (Data,Var,Abs) > > 0x0a, 0x24, 0x05, // USAGE (Day of Week) > 0x15, 0x00, // LOGICAL_MINIMUM (0) > 0x25, 0x06, // LOGICAL_MAXIMUM (6) > 0xa1, 0x02, // COLLECTION (Logical) > 0x0a, 0xc0, 0x08, // Day of Week: Sunday > 0x0a, 0xc1, 0x08, // Day of Week: Monday > 0x0a, 0xc2, 0x08, // Day of Week: Tuesday > 0x0a, 0xc3, 0x08, // Day of Week: Wednesday > 0x0a, 0xc4, 0x08, // Day of Week: Thursday > 0x0a, 0xc5, 0x08, // Day of Week: Friday > 0x0a, 0xc6, 0x08, // Day of Week: Saturday > 0x81, 0x02, // INPUT (Const,Arr,Abs) > 0xc0, // END_COLLECTION > > 0x0a, 0x25, 0x05, // USAGE (Hour) > 0x15, 0x00, // LOGICAL_MINIMUM (0) > 0x25, 0x17, // LOGICAL_MAXIMUM (23) > 0x65, 0x00, // UNIT (None) > 0x81, 0x02, // INPUT (Data,Var,Abs) > > 0x0a, 0x26, 0x05, // USAGE (Minute) > 0x15, 0x00, // LOGICAL_MINIMUM (0) > 0x25, 0x3b, // LOGICAL_MAXIMUM (59) > 0x65, 0x00, // UNIT (None) > 0x81, 0x02, // INPUT (Data,Var,Abs) > > 0x0a, 0x27, 0x05, // USAGE (Second) > 0x15, 0x00, // LOGICAL_MINIMUM (0) > 0x25, 0x3b, // LOGICAL_MAXIMUM (59) > 0x65, 0x00, // UNIT (None) > //0x66, 0x10, 0x01, // UNIT (second) > 0x81, 0x02, // INPUT (Data,Var,Abs) > > 0x0a, 0x28, 0x05, // USAGE (Millisecond) > 0x75, 0x10, // REPORT_SIZE (16 bits) > 0x65, 0x00, // UNIT (None) > 0x81, 0x02, // INPUT (Data,Var,Abs) > > 0xc0, // END_COLLECTION > 0xc0, // END_COLLECTION > --my-descriptor-- > >> >> We can use the existing HID parser in hid-core for hid_scan_report() >> by re-using the code from hid_open_report(). hid_parser_global, >> hid_parser_local and hid_parser_reserved does not have any side effects. >> We just need to reimplement the MAIN_ITEM callback to have a proper >> parsing without side effects. >> >> Instead of directly overwriting the ->group field, this patch introduce >> a ->flags field and then decide which group the device belongs to, >> depending on the whole parsing (not just the local item). This will be >> useful for Win 8 multitouch devices, which are multitouch devices and >> Win 8 certified (so 2 flags to check). >> >> Signed-off-by: Benjamin Tissoires >> --- >> drivers/hid/hid-core.c | 131 >> +++++++++++++++++++++++++++++++++++-------------- >> include/linux/hid.h | 4 ++ >> 2 files changed, 97 insertions(+), 38 deletions(-) >> >> diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c >> index 3efe19f..d8cdb0a 100644 >> --- a/drivers/hid/hid-core.c >> +++ b/drivers/hid/hid-core.c >> @@ -677,10 +677,49 @@ static u8 *fetch_item(__u8 *start, __u8 *end, >> struct hid_item *item) >> return NULL; >> } >> >> -static void hid_scan_usage(struct hid_device *hid, u32 usage) >> +static void hid_scan_input_usage(struct hid_parser *parser, u32 usage) >> { >> if (usage == HID_DG_CONTACTID) >> - hid->group = HID_GROUP_MULTITOUCH; >> + parser->flags |= HID_FLAG_MULTITOUCH; >> +} >> + >> +static void hid_scan_open_collection(struct hid_parser *parser, >> unsigned type) >> +{ >> + if (parser->global.usage_page == HID_UP_SENSOR && >> + type == HID_COLLECTION_PHYSICAL) >> + parser->flags |= HID_FLAG_SENSOR_HUB; >> +} >> + >> +static int hid_scan_main(struct hid_parser *parser, struct hid_item >> *item) >> +{ >> + __u32 data; >> + int i; >> + >> + data = item_udata(item); >> + >> + switch (item->tag) { >> + case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION: >> + hid_scan_open_collection(parser, data & 0xff); >> + break; >> + case HID_MAIN_ITEM_TAG_END_COLLECTION: >> + break; >> + case HID_MAIN_ITEM_TAG_INPUT: >> + for (i = 0; i < parser->local.usage_index; i++) >> + hid_scan_input_usage(parser, parser->local.usage[i]); >> + break; >> + case HID_MAIN_ITEM_TAG_OUTPUT: >> + break; >> + case HID_MAIN_ITEM_TAG_FEATURE: >> + break; >> + default: >> + hid_err(parser->device, "unknown main item tag 0x%x\n", >> + item->tag); >> + } >> + >> + /* Reset the local parser environment */ >> + memset(&parser->local, 0, sizeof(parser->local)); >> + >> + return 0; >> } >> >> /* >> @@ -690,49 +729,65 @@ static void hid_scan_usage(struct hid_device >> *hid, u32 usage) >> */ >> static int hid_scan_report(struct hid_device *hid) >> { >> - unsigned int page = 0, delim = 0; >> + struct hid_parser *parser; >> + struct hid_item item; >> __u8 *start = hid->dev_rdesc; >> __u8 *end = start + hid->dev_rsize; >> - unsigned int u, u_min = 0, u_max = 0; >> - struct hid_item item; >> + int ret; >> + static int (*dispatch_type[])(struct hid_parser *parser, >> + struct hid_item *item) = { >> + hid_scan_main, >> + hid_parser_global, >> + hid_parser_local, >> + hid_parser_reserved >> + }; >> >> - hid->group = HID_GROUP_GENERIC; >> + parser = vzalloc(sizeof(struct hid_parser)); >> + if (!parser) >> + return -ENOMEM; >> + >> + parser->device = hid; >> + >> + ret = -EINVAL; >> while ((start = fetch_item(start, end, &item)) != NULL) { >> - if (item.format != HID_ITEM_FORMAT_SHORT) >> - return -EINVAL; >> - if (item.type == HID_ITEM_TYPE_GLOBAL) { >> - if (item.tag == HID_GLOBAL_ITEM_TAG_USAGE_PAGE) >> - page = item_udata(&item) << 16; >> - } else if (item.type == HID_ITEM_TYPE_LOCAL) { >> - if (delim > 1) >> - break; >> - u = item_udata(&item); >> - if (item.size <= 2) >> - u += page; >> - switch (item.tag) { >> - case HID_LOCAL_ITEM_TAG_DELIMITER: >> - delim += !!u; >> - break; >> - case HID_LOCAL_ITEM_TAG_USAGE: >> - hid_scan_usage(hid, u); >> - break; >> - case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM: >> - u_min = u; >> - break; >> - case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM: >> - u_max = u; >> - for (u = u_min; u <= u_max; u++) >> - hid_scan_usage(hid, u); >> - break; >> + >> + if (item.format != HID_ITEM_FORMAT_SHORT) { >> + hid_err(hid, "unexpected long global item\n"); >> + goto out; >> + } >> + >> + if (dispatch_type[item.type](parser, &item)) { >> + hid_err(hid, "item %u %u %u %u parsing failed\n", >> + item.format, (unsigned)item.size, >> + (unsigned)item.type, (unsigned)item.tag); >> + goto out; >> + } >> + >> + if (start == end) { >> + if (parser->local.delimiter_depth) { >> + hid_err(hid, "unbalanced delimiter at end of report >> description\n"); >> + goto out; >> } >> - } else if (page == HID_UP_SENSOR && >> - item.type == HID_ITEM_TYPE_MAIN && >> - item.tag == HID_MAIN_ITEM_TAG_BEGIN_COLLECTION && >> - (item_udata(&item) & 0xff) == HID_COLLECTION_PHYSICAL) >> - hid->group = HID_GROUP_SENSOR_HUB; >> + ret = 0; >> + goto out; >> + } >> } >> >> - return 0; >> + hid_err(hid, "item fetching failed at offset %d\n", (int)(end - >> start)); >> +out: >> + switch (parser->flags) { >> + case HID_FLAG_MULTITOUCH: >> + hid->group = HID_GROUP_MULTITOUCH; >> + break; >> + case HID_FLAG_SENSOR_HUB: >> + hid->group = HID_GROUP_SENSOR_HUB; >> + break; >> + default: >> + hid->group = HID_GROUP_GENERIC; >> + } >> + >> + vfree(parser); >> + return ret; >> } >> >> /** >> diff --git a/include/linux/hid.h b/include/linux/hid.h >> index 5a4e789..7d823db 100644 >> --- a/include/linux/hid.h >> +++ b/include/linux/hid.h >> @@ -533,6 +533,9 @@ static inline void hid_set_drvdata(struct >> hid_device *hdev, void *data) >> #define HID_GLOBAL_STACK_SIZE 4 >> #define HID_COLLECTION_STACK_SIZE 4 >> >> +#define HID_FLAG_MULTITOUCH 0x0001 >> +#define HID_FLAG_SENSOR_HUB 0x0002 >> + >> struct hid_parser { >> struct hid_global global; >> struct hid_global global_stack[HID_GLOBAL_STACK_SIZE]; >> @@ -541,6 +544,7 @@ struct hid_parser { >> unsigned collection_stack[HID_COLLECTION_STACK_SIZE]; >> unsigned collection_stack_ptr; >> struct hid_device *device; >> + unsigned flags; >> }; >> >> struct hid_class_descriptor { >> > > Thanks, Srinivas -- 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/