MSI Megasky 580 does not initialize correct on modern pc:s with usb
using ehci.
This could be traced to the use of read buffer on the stack for control
messages.
Tested on Thinkpad X131e Ubuntu Mate 21.04 5.11.0-34-generic x86_64
and several other.
I installed mt352 and qt1010 from the latest media source
linux-media-2021-09-12-
6880fa6c5660.tar.bz2 and modify them the to put the buffer in kernel space.
dmesg before mod
[14703.648173] usb 1-1.2: new high-speed USB device number 8 using ehci-pci
[14703.765788] usb 1-1.2: New USB device found, idVendor=0db0,
idProduct=5580, bcdDevice= 1.10
[14703.765809] usb 1-1.2: New USB device strings: Mfr=1, Product=2,
SerialNumber=0
[14703.765818] usb 1-1.2: Product: DTV USB MINI
[14703.765824] usb 1-1.2: Manufacturer: DTV USB MINI
[14703.768016] dvb-usb: found a 'MSI Mega Sky 580 DVB-T USB2.0' in cold
state, will try to load a firmware
[14703.768146] dvb-usb: downloading firmware from file
'dvb-usb-megasky-02.fw'
[14704.615878] usb 1-1.2: USB disconnect, device number 8
[14704.840154] usb 1-1.2: new high-speed USB device number 9 using ehci-pci
[14704.960288] usb 1-1.2: New USB device found, idVendor=0db0,
idProduct=5580, bcdDevice= 0.95
[14704.960306] usb 1-1.2: New USB device strings: Mfr=1, Product=2,
SerialNumber=0
[14704.960312] usb 1-1.2: Product: DTV USB MINI
[14704.960317] usb 1-1.2: Manufacturer: ULi Electronics
[14704.961096] dvb-usb: found a 'MSI Mega Sky 580 DVB-T USB2.0' in warm
state.
[14704.961641] dvb-usb: will pass the complete MPEG2 transport stream to
the software demuxer.
[14704.961786] dvbdev: DVB: registering new adapter (MSI Mega Sky 580
DVB-T USB2.0)
[14704.961812] usb 1-1.2: media controller created
[14704.962990] dvbdev: dvb_create_media_entity: media entity 'dvb-demux'
registered.
[14705.017363] m920x_read = error: -11
[14705.017379] mt352_read_register: readreg error (reg=127, ret==-11)
[14705.017396] dvb-usb: no frontend was attached by 'MSI Mega Sky 580
DVB-T USB2.0'
[14705.017597] input: IR-receiver inside an USB DVB receiver as
/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.2/input/input23
[14705.017948] dvb-usb: schedule remote query interval to 100 msecs.
[14705.017966] dvb-usb: MSI Mega Sky 580 DVB-T USB2.0 successfully
initialized and connected.
diff qt1010.c
13a14,15
> u8 *b1=kmalloc(1,GFP_KERNEL);
>
18c20
<
.flags = I2C_M_RD, .buf = val, .len = 1 },
---
>
.flags = I2C_M_RD, .buf = b1, .len = 1 },
23a26
>
kfree(b1);
26c29,31
<
return 0;
---
>
*val=*b1;
> kfree(b1);
> return 0;
diff mt352.c72c72
<
u8 b1 [] = { 0 };
---
> u8 *b1=kmalloc(1,GFP_KERNEL);
84a85
>
kfree(b1);
87,88c88,90
<
<
return b1[0];
---
>
ret=*b1;
> kfree(b1);
>
return ret;
dmesg after mod
16681.187111] usb 1-1.2: new high-speed USB device number 10 using ehci-pci
[16681.300642] usb 1-1.2: New USB device found, idVendor=0db0,
idProduct=5580, bcdDevice= 1.10
[16681.300656] usb 1-1.2: New USB device strings: Mfr=1, Product=2,
SerialNumber=0
[16681.300661] usb 1-1.2: Product: DTV USB MINI
[16681.300665] usb 1-1.2: Manufacturer: DTV USB MINI
[16681.302264] dvb-usb: found a 'MSI Mega Sky 580 DVB-T USB2.0' in cold
state, will try to load a firmware
[16681.302348] dvb-usb: downloading firmware from file
'dvb-usb-megasky-02.fw'
[16682.119818] usb 1-1.2: USB disconnect, device number 10
[16682.343171] usb 1-1.2: new high-speed USB device number 11 using ehci-pci
[16682.459126] usb 1-1.2: New USB device found, idVendor=0db0,
idProduct=5580, bcdDevice= 0.95
[16682.459147] usb 1-1.2: New USB device strings: Mfr=1, Product=2,
SerialNumber=0
[16682.459155] usb 1-1.2: Product: DTV USB MINI
[16682.459162] usb 1-1.2: Manufacturer: ULi Electronics
[16682.459823] dvb-usb: found a 'MSI Mega Sky 580 DVB-T USB2.0' in warm
state.
[16682.461268] dvb-usb: will pass the complete MPEG2 transport stream to
the software demuxer.
[16682.461508] dvbdev: DVB: registering new adapter (MSI Mega Sky 580
DVB-T USB2.0)
[16682.461524] usb 1-1.2: media controller created
[16682.462359] dvbdev: dvb_create_media_entity: media entity 'dvb-demux'
registered.
[16682.516447] usb 1-1.2: DVB: registering adapter 0 frontend 0 (Zarlink
MT352 DVB-T)...
[16682.516478] dvbdev: dvb_create_media_entity: media entity 'Zarlink
MT352 DVB-T' registered.
[16682.526592] i2c i2c-8: qt1010: Quantek QT1010 successfully identified
[16682.527378] input: IR-receiver inside an USB DVB receiver as
/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.2/input/input24
[16682.527574] dvb-usb: schedule remote query interval to 100 msecs.
[16682.527590] dvb-usb: MSI Mega Sky 580 DVB-T USB2.0 successfully
initialized and connected.
Please verify my code, since C is not my primary programming language.
Even if Megasky is an old device, it’s still in the linux distribution
and I think it should work
properly.
I hope this modification will find its way into linux media.
R Kardell
