| Message ID | 20190327101848.25477-1-nsaenzjulienne@suse.de (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | 58e75155009cc800005629955d3482f36a1e0eec |
| Headers | show |
| Series | [v4] HID: core: move Usage Page concatenation to Main item | expand |
Hi Nicolas, V4 looks good to me. Thanks, Terry >-----Original Message----- >Subject: [PATCH v4] HID: core: move Usage Page concatenation to Main item >
On Thu, Mar 28, 2019 at 1:27 AM Junge, Terry <terry.junge@poly.com> wrote: > > Hi Nicolas, > > V4 looks good to me. Looks good to me too. Terry, can I consider this as a formal Rev-by you? Cheers, Benjamin > > Thanks, > Terry > > >-----Original Message----- > >Subject: [PATCH v4] HID: core: move Usage Page concatenation to Main item > >
On Thursday, March 28, 2019 6:49 AM Benjamin Tissoires <benjamin.tissoires@redhat.com> wrote: >> >> Hi Nicolas, >> >> V4 looks good to me. > >Looks good to me too. > >Terry, can I consider this as a formal Rev-by you? Benjamin, Yes, thank you. What is the normal way of formally indicating Rev-by? Regards, Terry > >Cheers, >Benjamin > >> >> Thanks, >> Terry >> >> >-----Original Message----- >> >Subject: [PATCH v4] HID: core: move Usage Page concatenation to Main >item >> >
On Fri, Mar 29, 2019 at 1:48 AM Junge, Terry <terry.junge@poly.com> wrote: > > On Thursday, March 28, 2019 6:49 AM Benjamin Tissoires <benjamin.tissoires@redhat.com> wrote: > >> > >> Hi Nicolas, > >> > >> V4 looks good to me. > > > >Looks good to me too. > > > >Terry, can I consider this as a formal Rev-by you? > > Benjamin, > > Yes, thank you. What is the normal way of formally indicating Rev-by? > Thanks. So giving a rev-by is described in https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst section 13. Basically, you just answer a patch with: "Reviewed-by: Your Name <your@address.sth>" (without quotes). This has 2 benefits: it's formal, and everybody understands it, and patchwork (at https://patchwork.kernel.org/patch/10873179/ for this patch) will catch it. Then with the patchwork client, I can apply the patch without having to manually add your tag :) (no need to resend one here, unless you want to give a try, I'll apply it manually). Cheers, Benjamin
On Wed, Mar 27, 2019 at 11:19 AM Nicolas Saenz Julienne <nsaenzjulienne@suse.de> wrote: > > As seen on some USB wireless keyboards manufactured by Primax, the HID > parser was using some assumptions that are not always true. In this case > it's s the fact that, inside the scope of a main item, an Usage Page > will always precede an Usage. > > The spec is not pretty clear as 6.2.2.7 states "Any usage that follows > is interpreted as a Usage ID and concatenated with the Usage Page". > While 6.2.2.8 states "When the parser encounters a main item it > concatenates the last declared Usage Page with a Usage to form a > complete usage value." Being somewhat contradictory it was decided to > match Window's implementation, which follows 6.2.2.8. > > In summary, the patch moves the Usage Page concatenation from the local > item parsing function to the main item parsing function. > > Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> > --- Applied to for-5.2/core with Terry's reviewed-by. Thanks everybody. Cheers, Benjamin > > v3->v4: - Use u8 instead of __u8 > - Remove overly complex usage size calculation > > v2->v3: - Update patch title > > v1->v2: - Add usage concatenation to hid_scan_main() > - Rework tests in hid-tools, making sure no-one is failing > > drivers/hid/hid-core.c | 36 ++++++++++++++++++++++++------------ > include/linux/hid.h | 1 + > 2 files changed, 25 insertions(+), 12 deletions(-) > > diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c > index 9993b692598f..852bbd303d9a 100644 > --- a/drivers/hid/hid-core.c > +++ b/drivers/hid/hid-core.c > @@ -218,13 +218,14 @@ static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type) > * Add a usage to the temporary parser table. > */ > > -static int hid_add_usage(struct hid_parser *parser, unsigned usage) > +static int hid_add_usage(struct hid_parser *parser, unsigned usage, u8 size) > { > if (parser->local.usage_index >= HID_MAX_USAGES) { > hid_err(parser->device, "usage index exceeded\n"); > return -1; > } > parser->local.usage[parser->local.usage_index] = usage; > + parser->local.usage_size[parser->local.usage_index] = size; > parser->local.collection_index[parser->local.usage_index] = > parser->collection_stack_ptr ? > parser->collection_stack[parser->collection_stack_ptr - 1] : 0; > @@ -486,10 +487,7 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) > return 0; > } > > - if (item->size <= 2) > - data = (parser->global.usage_page << 16) + data; > - > - return hid_add_usage(parser, data); > + return hid_add_usage(parser, data, item->size); > > case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM: > > @@ -498,9 +496,6 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) > return 0; > } > > - if (item->size <= 2) > - data = (parser->global.usage_page << 16) + data; > - > parser->local.usage_minimum = data; > return 0; > > @@ -511,9 +506,6 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) > return 0; > } > > - if (item->size <= 2) > - data = (parser->global.usage_page << 16) + data; > - > count = data - parser->local.usage_minimum; > if (count + parser->local.usage_index >= HID_MAX_USAGES) { > /* > @@ -533,7 +525,7 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) > } > > for (n = parser->local.usage_minimum; n <= data; n++) > - if (hid_add_usage(parser, n)) { > + if (hid_add_usage(parser, n, item->size)) { > dbg_hid("hid_add_usage failed\n"); > return -1; > } > @@ -547,6 +539,22 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) > return 0; > } > > +/* > + * Concatenate Usage Pages into Usages where relevant: > + * As per specification, 6.2.2.8: "When the parser encounters a main item it > + * concatenates the last declared Usage Page with a Usage to form a complete > + * usage value." > + */ > + > +static void hid_concatenate_usage_page(struct hid_parser *parser) > +{ > + int i; > + > + for (i = 0; i < parser->local.usage_index; i++) > + if (parser->local.usage_size[i] <= 2) > + parser->local.usage[i] += parser->global.usage_page << 16; > +} > + > /* > * Process a main item. > */ > @@ -556,6 +564,8 @@ static int hid_parser_main(struct hid_parser *parser, struct hid_item *item) > __u32 data; > int ret; > > + hid_concatenate_usage_page(parser); > + > data = item_udata(item); > > switch (item->tag) { > @@ -765,6 +775,8 @@ static int hid_scan_main(struct hid_parser *parser, struct hid_item *item) > __u32 data; > int i; > > + hid_concatenate_usage_page(parser); > + > data = item_udata(item); > > switch (item->tag) { > diff --git a/include/linux/hid.h b/include/linux/hid.h > index f9707d1dcb58..ac0c70b4ce10 100644 > --- a/include/linux/hid.h > +++ b/include/linux/hid.h > @@ -417,6 +417,7 @@ struct hid_global { > > struct hid_local { > unsigned usage[HID_MAX_USAGES]; /* usage array */ > + u8 usage_size[HID_MAX_USAGES]; /* usage size array */ > unsigned collection_index[HID_MAX_USAGES]; /* collection index array */ > unsigned usage_index; > unsigned usage_minimum; > -- > 2.21.0 >
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 9993b692598f..852bbd303d9a 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -218,13 +218,14 @@ static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type) * Add a usage to the temporary parser table. */ -static int hid_add_usage(struct hid_parser *parser, unsigned usage) +static int hid_add_usage(struct hid_parser *parser, unsigned usage, u8 size) { if (parser->local.usage_index >= HID_MAX_USAGES) { hid_err(parser->device, "usage index exceeded\n"); return -1; } parser->local.usage[parser->local.usage_index] = usage; + parser->local.usage_size[parser->local.usage_index] = size; parser->local.collection_index[parser->local.usage_index] = parser->collection_stack_ptr ? parser->collection_stack[parser->collection_stack_ptr - 1] : 0; @@ -486,10 +487,7 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) return 0; } - if (item->size <= 2) - data = (parser->global.usage_page << 16) + data; - - return hid_add_usage(parser, data); + return hid_add_usage(parser, data, item->size); case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM: @@ -498,9 +496,6 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) return 0; } - if (item->size <= 2) - data = (parser->global.usage_page << 16) + data; - parser->local.usage_minimum = data; return 0; @@ -511,9 +506,6 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) return 0; } - if (item->size <= 2) - data = (parser->global.usage_page << 16) + data; - count = data - parser->local.usage_minimum; if (count + parser->local.usage_index >= HID_MAX_USAGES) { /* @@ -533,7 +525,7 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) } for (n = parser->local.usage_minimum; n <= data; n++) - if (hid_add_usage(parser, n)) { + if (hid_add_usage(parser, n, item->size)) { dbg_hid("hid_add_usage failed\n"); return -1; } @@ -547,6 +539,22 @@ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) return 0; } +/* + * Concatenate Usage Pages into Usages where relevant: + * As per specification, 6.2.2.8: "When the parser encounters a main item it + * concatenates the last declared Usage Page with a Usage to form a complete + * usage value." + */ + +static void hid_concatenate_usage_page(struct hid_parser *parser) +{ + int i; + + for (i = 0; i < parser->local.usage_index; i++) + if (parser->local.usage_size[i] <= 2) + parser->local.usage[i] += parser->global.usage_page << 16; +} + /* * Process a main item. */ @@ -556,6 +564,8 @@ static int hid_parser_main(struct hid_parser *parser, struct hid_item *item) __u32 data; int ret; + hid_concatenate_usage_page(parser); + data = item_udata(item); switch (item->tag) { @@ -765,6 +775,8 @@ static int hid_scan_main(struct hid_parser *parser, struct hid_item *item) __u32 data; int i; + hid_concatenate_usage_page(parser); + data = item_udata(item); switch (item->tag) { diff --git a/include/linux/hid.h b/include/linux/hid.h index f9707d1dcb58..ac0c70b4ce10 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -417,6 +417,7 @@ struct hid_global { struct hid_local { unsigned usage[HID_MAX_USAGES]; /* usage array */ + u8 usage_size[HID_MAX_USAGES]; /* usage size array */ unsigned collection_index[HID_MAX_USAGES]; /* collection index array */ unsigned usage_index; unsigned usage_minimum;
As seen on some USB wireless keyboards manufactured by Primax, the HID parser was using some assumptions that are not always true. In this case it's s the fact that, inside the scope of a main item, an Usage Page will always precede an Usage. The spec is not pretty clear as 6.2.2.7 states "Any usage that follows is interpreted as a Usage ID and concatenated with the Usage Page". While 6.2.2.8 states "When the parser encounters a main item it concatenates the last declared Usage Page with a Usage to form a complete usage value." Being somewhat contradictory it was decided to match Window's implementation, which follows 6.2.2.8. In summary, the patch moves the Usage Page concatenation from the local item parsing function to the main item parsing function. Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> --- v3->v4: - Use u8 instead of __u8 - Remove overly complex usage size calculation v2->v3: - Update patch title v1->v2: - Add usage concatenation to hid_scan_main() - Rework tests in hid-tools, making sure no-one is failing drivers/hid/hid-core.c | 36 ++++++++++++++++++++++++------------ include/linux/hid.h | 1 + 2 files changed, 25 insertions(+), 12 deletions(-)