[PATCH v4 2/3] winex11.drv: Add EDID to the virtual desktop monitor device.

[Zhiyi Zhang]

On 9/7/21 8:38 PM, Eduard Permyakov wrote:
> Some applications use the EDID property of the monitor device
> to detect supported resolutions, and set the viewport size. Add
> a computed EDID to the virtual desktop monitor device to allow
> the virtual desktop driver to be better compatible with such
> applications.
>
> Most fields of the EDID contain details that are of no relevance
> to applications, so populate only the native resolution and physical
> monitor dimensions. This should cover the vast majority of use
> cases.
>
> Signed-off-by: Eduard Permyakov <epermyakov at codeweavers.com>
> ---
>  dlls/winex11.drv/desktop.c | 70 ++++++++++++++++++++++++++++++++++++--
>  1 file changed, 68 insertions(+), 2 deletions(-)
>
> diff --git a/dlls/winex11.drv/desktop.c b/dlls/winex11.drv/desktop.c
> index 71b3a0a5a27..cfa327bf809 100644
> --- a/dlls/winex11.drv/desktop.c
> +++ b/dlls/winex11.drv/desktop.c
> @@ -20,6 +20,7 @@
>   */
>  
>  #include "config.h"
> +#include <stdint.h>
>  #include <X11/cursorfont.h>
>  #include <X11/Xlib.h>
>  
> @@ -111,6 +112,69 @@ static void add_desktop_mode( DEVMODEW *mode, DWORD depth, DWORD width, DWORD he
>      mode->dmDisplayFrequency = 60;
>  }
>  
> +static void get_virtual_edid( unsigned char **edid, unsigned long *len )
> +{
> +    static const size_t desc_size = 128;
> +    /*Sample EDID for an LCD Desktop IT Display, from VESA spec */
> +    static const unsigned char default_edid[128] = {
> +        /* Header */
> +        0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00,
> +        /* Manufacturer's code name */
> +        0x04, 0x43,
> +        /* Product code */
> +        0x06, 0xf2,
> +        /* Serial Number */
> +        0x01, 0x00, 0x00, 0x00,
> +        /* Date of manufacture */
> +        0x01, 0x11,
> +        /* EDID version */
> +        0x01, 0x04,
> +        /* Standard characteristics */
> +        0x0f, 0x2b, 0x20, 0x78, 0x2b, 0x9c, 0x68, 0xa0,
> +        0x57, 0x4a, 0x9b, 0x26, 0x12, 0x48, 0x4c, 0xff,
> +        0xff, 0x80, 0xa9, 0x59, 0xa9, 0x4f, 0xa9, 0x4a,
> +        0xa9, 0x45, 0x81, 0x99, 0x81, 0x80, 0x61, 0x59,
> +        0x45, 0x59,
> +        /* First 18-byte data block (Preferred Timing Mode) */
> +        0x48, 0x3f, 0x40, 0x30, 0x62, 0xb0, 0x32, 0x40,
> +        0x40, 0xc0, 0x13, 0x00, 0xab, 0x40, 0x11, 0x00,
> +        0x00, 0x1e,
> +        /* Second 18-byte data block */
> +        0x00, 0x00, 0x00, 0xfd, 0x00, 0x32, 0x5a, 0x1e,
> +        0x6e, 0x17, 0x04, 0x11, 0x00, 0xc8, 0x90, 0x00,
> +        0x50, 0x3c,
> +        /* Third 18-byte data block */
> +        0x00, 0x00, 0x00, 0x00, 0xf7, 0x00, 0x0a, 0xf7,
> +        0x0f, 0x03, 0x87, 0xc0, 0x00, 0x00, 0x00, 0x00,
> +        0x00, 0x00,
> +        /* Fourth 18-byte data block */
> +        0x00, 0x00, 0x00, 0xfc, 0x00, 0x41, 0x42, 0x43,
> +        0x20, 0x4c, 0x43, 0x44, 0x32, 0x31, 0x0a, 0x20,
> +        0x20, 0x20,
> +        /* Extension flag */
> +        0x00,
> +        /* Checksum */
> +        0x0b,
> +    };
> +
> +    *edid = heap_calloc( desc_size, 1 );

you can replace desc_size with sizeof(default_edid).

> +    if (!*edid)
> +    {
> +        *len = 0;
> +        return;
> +    }
> +
> +    memcpy( *edid, default_edid, desc_size );
> +    *len = desc_size;
> +
> +    /* Set the native resolution in the Preferred Timing Mode descriptor */
> +    (*edid)[0x38] = max_width & 0xff;
> +    (*edid)[0x3a] = ((max_width >> 8) & 0xf) << 4;
> +
> +    (*edid)[0x3b] = max_height & 0xff;
> +    (*edid)[0x3d] = ((max_height >> 8) & 0xf) << 4;

Obviously, checksum is invalid after you modify the data.

> +}
> +
>  static BOOL X11DRV_desktop_get_modes( ULONG_PTR id, DWORD flags, DEVMODEW **new_modes, UINT *mode_count )
>  {
>      UINT depth_idx, size_idx, mode_idx = 0;
> @@ -265,8 +329,7 @@ static BOOL X11DRV_desktop_get_monitors( ULONG_PTR adapter_id, struct x11drv_mon
>      SetRect( &monitor->rc_work, 0, 0, desktop_width, desktop_height );
>      query_desktop_work_area( &monitor->rc_work );
>      monitor->state_flags = DISPLAY_DEVICE_ATTACHED;
> -    monitor->edid_len = 0;
> -    monitor->edid = NULL;
> +    get_virtual_edid( &monitor->edid, &monitor->edid_len );
>      if (desktop_width && desktop_height)
>          monitor->state_flags |= DISPLAY_DEVICE_ACTIVE;
>  
> @@ -277,6 +340,9 @@ static BOOL X11DRV_desktop_get_monitors( ULONG_PTR adapter_id, struct x11drv_mon
>  
>  static void X11DRV_desktop_free_monitors( struct x11drv_monitor *monitors, int count )
>  {
> +    int i;
> +    for (i = 0; i < count; i++)
> +        heap_free( monitors[i].edid );
>      heap_free( monitors );
>  }
>