| Message ID | 20171123093947.21388-1-benjamin.tissoires@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Nov 23 2017 or thereabouts, Benjamin Tissoires wrote: > This is something that bothered us from a long time. When hid-input > doesn't know how to map a usage, it uses *_MISC. But there is something > else which increments the usage if the evdev code is already used. > > This leads to few issues: > - some devices may have their ABS_X mapped to ABS_Y if they export a bad > set of usages (see the DragonRise joysticks IIRC -> fixed in a specific > HID driver) > - *_MISC + N might (will) conflict with other defined axes (my Logitech > H800 exports some multitouch axes because of that) > - this prevents to freely add some new evdev usages, because "hey, my > headset will now report ABS_COFFEE, and it's not coffee capable". > > So let's try to kill this nonsense, and hope we won't break too many > devices. > > I my headset case, the ABS_MISC axes are created because of some > proprietary usages, so we might not break that many devices. > > For backward compatibility, a quirk HID_QUIRK_INCREMENT_USAGE_ON_DUPLICATE > is created and can be applied to any device that needs this behavior. > > Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> > --- > > Hi Jiri, > > this is obviously 4.16 material. It applies on top of your > for-4.16/hid-quirks-cleanup/_base. > > Cheers, > Benjamin > > drivers/hid/hid-input.c | 33 +++++++++++++++++++++++++++++++-- > include/linux/hid.h | 2 ++ > 2 files changed, 33 insertions(+), 2 deletions(-) > > diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c > index 04d01b57d94c..8e824d1e9258 100644 > --- a/drivers/hid/hid-input.c > +++ b/drivers/hid/hid-input.c > @@ -1100,8 +1100,31 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel > > set_bit(usage->type, input->evbit); > > - while (usage->code <= max && test_and_set_bit(usage->code, bit)) > - usage->code = find_next_zero_bit(bit, max + 1, usage->code); > + /* > + * This part is *really* controversial: > + * - HID aims at being generic so we should do our best to export > + * all incoming events > + * - HID describes what events are, so there is no reason for ABS_X > + * to be mapped to ABS_Y > + * - HID is using *_MISC+N as a default value, but nothing prevents > + * *_MISC+N to overwrite a legitimate even, which confuses userspace > + * (for instance ABS_MISC + 7 is ABS_MT_SLOT, which has a different > + * processing) > + * > + * If devices still want to use this (at their own risk), they will > + * have to use the quirk HID_QUIRK_INCREMENT_USAGE_ON_DUPLICATE, but > + * the default should be a reliable mapping. > + */ > + while (usage->code <= max && test_and_set_bit(usage->code, bit)) { > + if (device->quirks & HID_QUIRK_INCREMENT_USAGE_ON_DUPLICATE) { > + usage->code = find_next_zero_bit(bit, > + max + 1, > + usage->code); > + } else { > + device->status |= HID_STAT_DUP_DETECTED; > + goto ignore; > + } > + } > > if (usage->code > max) > goto ignore; > @@ -1610,6 +1633,8 @@ int hidinput_connect(struct hid_device *hid, unsigned int force) > INIT_LIST_HEAD(&hid->inputs); > INIT_WORK(&hid->led_work, hidinput_led_worker); > > + hid->status &= ~HID_STAT_DUP_DETECTED; > + > if (!force) { > for (i = 0; i < hid->maxcollection; i++) { > struct hid_collection *col = &hid->collection[i]; > @@ -1676,6 +1701,10 @@ int hidinput_connect(struct hid_device *hid, unsigned int force) > goto out_unwind; > } > > + if (hid->status & HID_STAT_DUP_DETECTED) > + hid_info(hid, > + "Some usages could not be mapped, please use HID_QUIRK_INCREMENT_USAGE_ON_DUPLICATE if this is legitimate.\n"); This info log is getting really annoying, especially with teh hid-generic auto-binding. All the multitouch devices will report it, and this is not something we like. Maybe we should use it with hid_debug instead? > + > return 0; > > out_unwind: > diff --git a/include/linux/hid.h b/include/linux/hid.h > index 39cdeb205caa..076876a61a05 100644 > --- a/include/linux/hid.h > +++ b/include/linux/hid.h > @@ -343,6 +343,7 @@ struct hid_item { > #define HID_QUIRK_SKIP_OUTPUT_REPORT_ID 0x00020000 > #define HID_QUIRK_NO_OUTPUT_REPORTS_ON_INTR_EP 0x00040000 > #define HID_QUIRK_HAVE_SPECIAL_DRIVER 0x00080000 > +#define HID_QUIRK_INCREMENT_USAGE_ON_DUPLICATE 0x00100000 > #define HID_QUIRK_FULLSPEED_INTERVAL 0x10000000 > #define HID_QUIRK_NO_INIT_REPORTS 0x20000000 > #define HID_QUIRK_NO_IGNORE 0x40000000 > @@ -500,6 +501,7 @@ struct hid_output_fifo { > > #define HID_STAT_ADDED 1 > #define HID_STAT_PARSED 2 > +#define HID_STAT_DUP_DETECTED 3 This is really embarrassing (and took me 2 days to debug). The value should be 4, not 3. I'll send a followup with an additional one that convert all of those with the BIT() macro. Cheers, Benjamin > > struct hid_input { > struct list_head list; > -- > 2.14.3 > -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index 04d01b57d94c..8e824d1e9258 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -1100,8 +1100,31 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel set_bit(usage->type, input->evbit); - while (usage->code <= max && test_and_set_bit(usage->code, bit)) - usage->code = find_next_zero_bit(bit, max + 1, usage->code); + /* + * This part is *really* controversial: + * - HID aims at being generic so we should do our best to export + * all incoming events + * - HID describes what events are, so there is no reason for ABS_X + * to be mapped to ABS_Y + * - HID is using *_MISC+N as a default value, but nothing prevents + * *_MISC+N to overwrite a legitimate even, which confuses userspace + * (for instance ABS_MISC + 7 is ABS_MT_SLOT, which has a different + * processing) + * + * If devices still want to use this (at their own risk), they will + * have to use the quirk HID_QUIRK_INCREMENT_USAGE_ON_DUPLICATE, but + * the default should be a reliable mapping. + */ + while (usage->code <= max && test_and_set_bit(usage->code, bit)) { + if (device->quirks & HID_QUIRK_INCREMENT_USAGE_ON_DUPLICATE) { + usage->code = find_next_zero_bit(bit, + max + 1, + usage->code); + } else { + device->status |= HID_STAT_DUP_DETECTED; + goto ignore; + } + } if (usage->code > max) goto ignore; @@ -1610,6 +1633,8 @@ int hidinput_connect(struct hid_device *hid, unsigned int force) INIT_LIST_HEAD(&hid->inputs); INIT_WORK(&hid->led_work, hidinput_led_worker); + hid->status &= ~HID_STAT_DUP_DETECTED; + if (!force) { for (i = 0; i < hid->maxcollection; i++) { struct hid_collection *col = &hid->collection[i]; @@ -1676,6 +1701,10 @@ int hidinput_connect(struct hid_device *hid, unsigned int force) goto out_unwind; } + if (hid->status & HID_STAT_DUP_DETECTED) + hid_info(hid, + "Some usages could not be mapped, please use HID_QUIRK_INCREMENT_USAGE_ON_DUPLICATE if this is legitimate.\n"); + return 0; out_unwind: diff --git a/include/linux/hid.h b/include/linux/hid.h index 39cdeb205caa..076876a61a05 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -343,6 +343,7 @@ struct hid_item { #define HID_QUIRK_SKIP_OUTPUT_REPORT_ID 0x00020000 #define HID_QUIRK_NO_OUTPUT_REPORTS_ON_INTR_EP 0x00040000 #define HID_QUIRK_HAVE_SPECIAL_DRIVER 0x00080000 +#define HID_QUIRK_INCREMENT_USAGE_ON_DUPLICATE 0x00100000 #define HID_QUIRK_FULLSPEED_INTERVAL 0x10000000 #define HID_QUIRK_NO_INIT_REPORTS 0x20000000 #define HID_QUIRK_NO_IGNORE 0x40000000 @@ -500,6 +501,7 @@ struct hid_output_fifo { #define HID_STAT_ADDED 1 #define HID_STAT_PARSED 2 +#define HID_STAT_DUP_DETECTED 3 struct hid_input { struct list_head list;
This is something that bothered us from a long time. When hid-input doesn't know how to map a usage, it uses *_MISC. But there is something else which increments the usage if the evdev code is already used. This leads to few issues: - some devices may have their ABS_X mapped to ABS_Y if they export a bad set of usages (see the DragonRise joysticks IIRC -> fixed in a specific HID driver) - *_MISC + N might (will) conflict with other defined axes (my Logitech H800 exports some multitouch axes because of that) - this prevents to freely add some new evdev usages, because "hey, my headset will now report ABS_COFFEE, and it's not coffee capable". So let's try to kill this nonsense, and hope we won't break too many devices. I my headset case, the ABS_MISC axes are created because of some proprietary usages, so we might not break that many devices. For backward compatibility, a quirk HID_QUIRK_INCREMENT_USAGE_ON_DUPLICATE is created and can be applied to any device that needs this behavior. Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> --- Hi Jiri, this is obviously 4.16 material. It applies on top of your for-4.16/hid-quirks-cleanup/_base. Cheers, Benjamin drivers/hid/hid-input.c | 33 +++++++++++++++++++++++++++++++-- include/linux/hid.h | 2 ++ 2 files changed, 33 insertions(+), 2 deletions(-)