Message ID | 1437668415-14569-1-git-send-email-andrew.shadura@collabora.co.uk (mailing list archive) |
---|---|
State | Superseded, archived |
Delegated to: | Jiri Kosina |
Headers | show |
Hi Andrew, [resurrecting this following a ping from Andrew] On Thu, Jul 23, 2015 at 12:20 PM, Andrew Shadura <andrew.shadura@collabora.co.uk> wrote: > PenMount USB resistive touchscreen reports it has three buttons, while in reality > it doesn't have any and doesn't support active styli, and only generates touch > events. > > Signed-off-by: Andrew Shadura <andrew.shadura@collabora.co.uk> > --- > drivers/hid/hid-penmount.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/drivers/hid/hid-penmount.c b/drivers/hid/hid-penmount.c > index c11dce8..98ea1c12 100644 > --- a/drivers/hid/hid-penmount.c > +++ b/drivers/hid/hid-penmount.c > @@ -30,6 +30,23 @@ static int penmount_input_mapping(struct hid_device *hdev, > return 0; > } > > +static __u8 *penmount_report_fixup(struct hid_device *hdev, __u8 *rdesc, > + unsigned int *rsize) > +{ > + if (*rsize == 76 && > + rdesc[2] == 0x09 && rdesc[3] == 0x02 /* mouse */ && > + rdesc[22] == 0x05 && rdesc[23] == 0x09 /* button */ && > + rdesc[26] == 0x29 && rdesc[27] == 0x03 /* maximum */ && > + rdesc[32] == 0x95 && rdesc[33] == 0x02 /* report count */) { > + hid_info(hdev, > + "fixing up PenMount USB touchscreen report descriptor\n"); > + > + rdesc[27] = 0x01; /* just one button */ > + rdesc[33] = 0x01; /* just one report */ This is wrong. Changing this value shifts all the parsing of the rest of the report descriptor. So if this is the last field in the current report, then it might work. If not, then you are screwing the rest of the report. You can have 2 solutions to fix that: - either you still use a report fixup and you add an extra const field with a vendor usage page after this one (but that means allocating a new report descriptor slightly larger) - either you don't use a report fixup at all and ignore the extra buttons in .input_mapping(). Cheers, Benjamin > + } > + return rdesc; > +} > + > static const struct hid_device_id penmount_devices[] = { > { HID_USB_DEVICE(USB_VENDOR_ID_PENMOUNT, USB_DEVICE_ID_PENMOUNT_6000) }, > { } > @@ -39,6 +56,7 @@ MODULE_DEVICE_TABLE(hid, penmount_devices); > static struct hid_driver penmount_driver = { > .name = "hid-penmount", > .id_table = penmount_devices, > + .report_fixup = penmount_report_fixup, > .input_mapping = penmount_input_mapping, > }; > > -- > 2.1.4 > > -- > 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 -- 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-penmount.c b/drivers/hid/hid-penmount.c index c11dce8..98ea1c12 100644 --- a/drivers/hid/hid-penmount.c +++ b/drivers/hid/hid-penmount.c @@ -30,6 +30,23 @@ static int penmount_input_mapping(struct hid_device *hdev, return 0; } +static __u8 *penmount_report_fixup(struct hid_device *hdev, __u8 *rdesc, + unsigned int *rsize) +{ + if (*rsize == 76 && + rdesc[2] == 0x09 && rdesc[3] == 0x02 /* mouse */ && + rdesc[22] == 0x05 && rdesc[23] == 0x09 /* button */ && + rdesc[26] == 0x29 && rdesc[27] == 0x03 /* maximum */ && + rdesc[32] == 0x95 && rdesc[33] == 0x02 /* report count */) { + hid_info(hdev, + "fixing up PenMount USB touchscreen report descriptor\n"); + + rdesc[27] = 0x01; /* just one button */ + rdesc[33] = 0x01; /* just one report */ + } + return rdesc; +} + static const struct hid_device_id penmount_devices[] = { { HID_USB_DEVICE(USB_VENDOR_ID_PENMOUNT, USB_DEVICE_ID_PENMOUNT_6000) }, { } @@ -39,6 +56,7 @@ MODULE_DEVICE_TABLE(hid, penmount_devices); static struct hid_driver penmount_driver = { .name = "hid-penmount", .id_table = penmount_devices, + .report_fixup = penmount_report_fixup, .input_mapping = penmount_input_mapping, };
PenMount USB resistive touchscreen reports it has three buttons, while in reality it doesn't have any and doesn't support active styli, and only generates touch events. Signed-off-by: Andrew Shadura <andrew.shadura@collabora.co.uk> --- drivers/hid/hid-penmount.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)