Re: [Qemu-devel] [4253] Fix USB and HID report descriptors for mouse and tablet.

[Alexander Graf]

As of this commit the USB mouse wheel works, but is inverted.

I'm also having trouble understanding the hex descriptor blobs. Is  
there any chance someone who just "knows" what these mean could  
comment them in the source? That would be very helpful.

Thank you,

Alex

On Apr 26, 2008, at 3:43 AM, Andrzej Zaborowski wrote:

> Revision: 4253
>          http://svn.sv.gnu.org/viewvc/? 
> view=rev&root=qemu&revision=4253
> Author:   balrog
> Date:     2008-04-26 01:43:07 +0000 (Sat, 26 Apr 2008)
>
> Log Message:
> -----------
> Fix USB and HID report descriptors for mouse and tablet.
>
> Modified Paths:
> --------------
>    trunk/hw/usb-hid.c
>
> Modified: trunk/hw/usb-hid.c
> ===================================================================
> --- trunk/hw/usb-hid.c  2008-04-25 00:59:43 UTC (rev 4252)
> +++ trunk/hw/usb-hid.c  2008-04-26 01:43:07 UTC (rev 4253)
> @@ -134,14 +134,14 @@
>         0x00,        /*  u8 country_code */
>         0x01,        /*  u8 num_descriptors */
>         0x22,        /*  u8 type; Report */
> -        50, 0,       /*  u16 len */
> +        52, 0,       /*  u16 len */
>
>         /* one endpoint (status change endpoint) */
>         0x07,       /*  u8  ep_bLength; */
>         0x05,       /*  u8  ep_bDescriptorType; Endpoint */
>         0x81,       /*  u8  ep_bEndpointAddress; IN Endpoint 1 */
>         0x03,       /*  u8  ep_bmAttributes; Interrupt */
> -       0x03, 0x00, /*  u16 ep_wMaxPacketSize; */
> +       0x04, 0x00, /*  u16 ep_wMaxPacketSize; */
>         0x0a,       /*  u8  ep_bInterval; (255ms -- usb 2.0 spec) */
> };
>
> @@ -260,16 +260,14 @@
>     0xA1, 0x00, 0x05, 0x09, 0x19, 0x01, 0x29, 0x03,
>     0x15, 0x00, 0x25, 0x01, 0x95, 0x03, 0x75, 0x01,
>     0x81, 0x02, 0x95, 0x01, 0x75, 0x05, 0x81, 0x01,
> -    0x05, 0x01, 0x09, 0x30, 0x09, 0x31, 0x15, 0x81,
> -    0x25, 0x7F, 0x75, 0x08, 0x95, 0x02, 0x81, 0x06,
> -    0x05, 0x01, 0x09, 0x38, 0x15, 0x81, 0x25, 0x7F,
> -    0x35, 0x00, 0x45, 0x00, 0x75, 0x08, 0x95, 0x01,
> -    0x81, 0x02, 0xC0, 0xC0,
> +    0x05, 0x01, 0x09, 0x30, 0x09, 0x31, 0x09, 0x38,
> +    0x15, 0x81, 0x25, 0x7F, 0x75, 0x08, 0x95, 0x03,
> +    0x81, 0x06, 0xC0, 0xC0,
> };
>
> static const uint8_t qemu_tablet_hid_report_descriptor[] = {
>         0x05, 0x01, /* Usage Page Generic Desktop */
> -        0x09, 0x01, /* Usage Mouse */
> +        0x09, 0x01, /* Usage Pointer */
>         0xA1, 0x01, /* Collection Application */
>         0x09, 0x01, /* Usage Pointer */
>         0xA1, 0x00, /* Collection Physical */
> @@ -283,7 +281,7 @@
>         0x81, 0x02, /* Input (Data, Var, Abs) */
>         0x95, 0x01, /* Report Count 1 */
>         0x75, 0x05, /* Report Size 5 */
> -        0x81, 0x01, /* Input (Cnst, Var, Abs) */
> +        0x81, 0x01, /* Input (Cnst, Array, Abs) */
>         0x05, 0x01, /* Usage Page Generic Desktop */
>         0x09, 0x30, /* Usage X */
>         0x09, 0x31, /* Usage Y */
> @@ -302,7 +300,7 @@
>         0x45, 0x00, /* Physical Maximum 0 (same as logical) */
>         0x75, 0x08, /* Report Size 8 */
>         0x95, 0x01, /* Report Count 1 */
> -        0x81, 0x02, /* Input (Data, Var, Rel) */
> +        0x81, 0x06, /* Input (Data, Var, Rel) */
>         0xC0,       /* End Collection */
>         0xC0,       /* End Collection */
> };
> @@ -495,14 +493,15 @@
>     if (s->buttons_state & MOUSE_EVENT_MBUTTON)
>         b |= 0x04;
>
> -    buf[0] = b;
> -    buf[1] = dx;
> -    buf[2] = dy;
> -    l = 3;
> -    if (len >= 4) {
> -        buf[3] = dz;
> -        l = 4;
> -    }
> +    l = 0;
> +    if (len > l)
> +        buf[l ++] = b;
> +    if (len > l)
> +        buf[l ++] = dx;
> +    if (len > l)
> +        buf[l ++] = dy;
> +    if (len > l)
> +        buf[l ++] = dz;
>     return l;
> }