Il 02/06/2013 22:04, Antti Palosaari ha scritto: > On 06/02/2013 10:51 PM, Gianluca Gennari wrote: >> Il 02/06/2013 21:30, Antti Palosaari ha scritto: >>> On 06/02/2013 09:56 PM, Gianluca Gennari wrote: >>>> req_r820t wants a buffer with a size of 5 bytes, but the buffer 'buf' >>>> has a size of 2 bytes. >>>> >>>> This patch fixes the kernel oops with the r820t driver on old kernels >>>> during the probe stage. >>>> Successfully tested on a 2.6.32 32 bit kernel (Ubuntu 10.04). >>>> Hopefully it will also help with the random stability issues reported >>>> by some user on the linux-media list. >>>> >>>> This patch and https://patchwork.kernel.org/patch/2524651/ >>>> should go in the next 3.10-rc release, as they fix potential kernel >>>> crashes. >>>> >>>> Signed-off-by: Gianluca Gennari <gennarone@xxxxxxxxx> >>>> --- >>>> drivers/media/usb/dvb-usb-v2/rtl28xxu.c | 2 +- >>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/media/usb/dvb-usb-v2/rtl28xxu.c >>>> b/drivers/media/usb/dvb-usb-v2/rtl28xxu.c >>>> index 22015fe..48f2e6f 100644 >>>> --- a/drivers/media/usb/dvb-usb-v2/rtl28xxu.c >>>> +++ b/drivers/media/usb/dvb-usb-v2/rtl28xxu.c >>>> @@ -360,7 +360,7 @@ static int rtl2832u_read_config(struct >>>> dvb_usb_device *d) >>>> { >>>> struct rtl28xxu_priv *priv = d_to_priv(d); >>>> int ret; >>>> - u8 buf[2]; >>>> + u8 buf[5]; >>>> /* open RTL2832U/RTL2832 I2C gate */ >>>> struct rtl28xxu_req req_gate_open = {0x0120, 0x0011, 0x0001, >>>> "\x18"}; >>>> /* close RTL2832U/RTL2832 I2C gate */ >>>> >>> >>> Gianluca, could you make that probe to check chip id as usually. Read >>> register 0x00 and check value 0x69. Also, please test if writing to that >>> address different value will not change register value to see it is >>> really chip id. >>> >>> regards >>> Antti >>> >> >> Hi Antti, >> surely it makes sense. I will not have the time to check it until the >> end of the coming week, so if someone else wants to do it in advance I >> will not take offence ;-) >> >> Regards, >> Gianluca >> > > Yeah. I would not like to extend that buf to 5 as it is not "proper" > solution. Current check is more like just a check that there is some > chip on that I2C address. Reading one byte makes as much sense as > reading 5 bytes. Maybe Mauro has added that probe "lets implement it > later" and then forget... I found the time to do a quick test; this is the code: struct rtl28xxu_req req_r820t = {0x0034, CMD_I2C_RD, 1, buf}; struct rtl28xxu_req req_r820t_write = {0x0034, CMD_I2C_WR, 1, buf}; [snip] /* check R820T ID register; reg=00 val=69 */ ret = rtl28xxu_ctrl_msg(d, &req_r820t); if (ret == 0 && buf[0] == 0x69) { priv->tuner = TUNER_RTL2832_R820T; priv->tuner_name = "R820T"; //goto found; } dev_info(&d->udev->dev, "r820t tuner ID: %d\n", buf[0]); buf[0] = 0; ret = rtl28xxu_ctrl_msg(d, &req_r820t_write); if (ret == 0) { dev_info(&d->udev->dev, "successfully wrote newr820t tuner ID: %d\n", buf[0]); } ret = rtl28xxu_ctrl_msg(d, &req_r820t); if (ret == 0 && buf[0] == 0x69) { dev_info(&d->udev->dev, "Confirmed r820t tuner ID: %d\n", buf[0]); } dev_info(&d->udev->dev, "r820t tuner ID: %d\n", buf[0]); and this is the result: [ 3416.403807] usb 2-1.1: dvb_usb_v2: found a 'Realtek RTL2832U reference design' in warm state [ 3416.403855] usbcore: registered new interface driver dvb_usb_rtl28xxu [ 3416.468531] usb 2-1.1: r820t tuner ID: 105 [ 3416.470657] usb 2-1.1: successfully wrote newr820t tuner ID: 0 [ 3416.472838] usb 2-1.1: Confirmed r820t tuner ID: 105 [ 3416.472842] usb 2-1.1: r820t tuner ID: 105 [ 3416.474934] usb 2-1.1: dvb_usb_v2: will pass the complete MPEG2 transport stream to the software demuxer [ 3416.474953] DVB: registering new adapter (Realtek RTL2832U reference design) [ 3416.491121] usb 2-1.1: DVB: registering adapter 0 frontend 0 (Realtek RTL2832 (DVB-T))... [ 3416.505607] r820t 0-001a: creating new instance [ 3416.517646] r820t 0-001a: Rafael Micro r820t successfully identified [ 3416.524730] Registered IR keymap rc-empty [ 3416.524954] input: Realtek RTL2832U reference design as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.1/rc/rc0/input20 [ 3416.525133] rc0: Realtek RTL2832U reference design as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.1/rc/rc0 [ 3416.525141] usb 2-1.1: dvb_usb_v2: schedule remote query interval to 400 msecs [ 3416.537261] usb 2-1.1: dvb_usb_v2: 'Realtek RTL2832U reference design' successfully initialized and connected so it looks OK. I will post a v2 patch. > Northern part of Finland has has very warm weather now in two weeks and > I haven't found any time to code now :D Crazy, 25-30 C degrees every > day, hottest place in whole Europe :] I really hope it will go back to > normal rainy and cold weather soon that I can jump back to coding... LOL, you should take a vacation here in Italy: you will find all the cold and rain you need to produce some nice code ;-) Just make sure your hotel has free wi-fi, or you'll end up spending more on Internet access than on food :P > > regards > Antti > Regards, Gianluca -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
