From: Mauro Carvalho Chehab <mchehab@redhat.com>
To: Greg KH <gregkh@linuxfoundation.org>
Cc: Antti Palosaari <crope@iki.fi>, Kay Sievers <kay@redhat.com>,
Linux Media Mailing List <linux-media@vger.kernel.org>
Subject: Re: [PATCH RFC 3/4] em28xx: Workaround for new udev versions
Date: Tue, 26 Jun 2012 18:21:02 -0300 [thread overview]
Message-ID: <4FEA27BE.8020306@redhat.com> (raw)
In-Reply-To: <20120626204242.GC3885@kroah.com>
Em 26-06-2012 17:42, Greg KH escreveu:
> On Tue, Jun 26, 2012 at 04:34:21PM -0300, Mauro Carvalho Chehab wrote:
>> New udev-182 seems to be buggy: even when usermode is enabled, it
>> insists on needing that probe would defer any firmware requests.
>> So, drivers with firmware need to defer probe for the first
>> driver's core request, otherwise an useless penalty of 30 seconds
>> happens, as udev will refuse to load any firmware.
>>
>> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
>> ---
>>
>> Note: this patch adds an ugly printk there, in order to allow testing it better.
>> This will be removed at the final version.
>>
>> drivers/media/video/em28xx/em28xx-cards.c | 39 +++++++++++++++++++++++++----
>> 1 file changed, 34 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/media/video/em28xx/em28xx-cards.c b/drivers/media/video/em28xx/em28xx-cards.c
>> index 9229cd2..9a1c16c 100644
>> --- a/drivers/media/video/em28xx/em28xx-cards.c
>> +++ b/drivers/media/video/em28xx/em28xx-cards.c
>> @@ -60,6 +60,8 @@ static unsigned int card[] = {[0 ... (EM28XX_MAXBOARDS - 1)] = UNSET };
>> module_param_array(card, int, NULL, 0444);
>> MODULE_PARM_DESC(card, "card type");
>>
>> +static bool is_em28xx_initialized;
>> +
>> /* Bitmask marking allocated devices from 0 to EM28XX_MAXBOARDS - 1 */
>> static unsigned long em28xx_devused;
>>
>> @@ -3167,11 +3169,14 @@ static int em28xx_usb_probe(struct usb_interface *interface,
>> * postponed, as udev may not be ready yet to honour firmware
>> * load requests.
>> */
>> +printk("em28xx: init = %d, userspace_is_disabled = %d, needs firmware = %d\n",
>> + is_em28xx_initialized,
>> + is_usermodehelp_disabled(), em28xx_boards[id->driver_info].needs_firmware);
>
> debug code?
Yes, temporary debug code, for people @linux-media that might be interested
on testing the patch. It will be removed at the final version, of course.
> Also, this doesn't seem wise. probe() will be called and
> is_em28xx_initialized will be 0 before it can be set if the device is
> present when the module is loaded. But, if a new device is added to the
> system after probe() already runs, is_em28xx_initialized will be 1, yet
> it isn't true for this new device.
Yes.
>
> So this doesn't seem like a valid solution, even if you were wanting to
> paper over a udev bug.
The problem with udev-182 is that it blocks firmware load while
mode_init() is happening. Only after the end of module_init(), udev will
handle request_firmware.
This is what happens before this patch series:
[ 3.605783] tvp5150 0-005c: tvp5150am1 detected.
[ 3.627674] tuner 0-0061: Tuner -1 found with type(s) Radio TV.
[ 3.633695] xc2028 0-0061: creating new instance
[ 3.638406] xc2028 0-0061: type set to XCeive xc2028/xc3028 tuner
[ 64.422633] xc2028 0-0061: Error: firmware xc3028-v27.fw not found.
[ 64.429090] em28xx #0: Config register raw data: 0xd0
[ 64.434959] em28xx #0: AC97 vendor ID = 0xffffffff
[ 64.440206] em28xx #0: AC97 features = 0x6a90
[ 64.444654] em28xx #0: Empia 202 AC97 audio processor detected
[ 64.607494] em28xx #0: v4l2 driver version 0.1.3
[ 125.574760] xc2028 0-0061: Error: firmware xc3028-v27.fw not found.
[ 125.645012] em28xx #0: V4L2 video device registered as video0
[ 125.650851] em28xx #0: V4L2 VBI device registered as vbi0
The 60s delay is due to the bug (firmware doesn't load there just
because I didn't ask dracut to add it there).
After the patch series, the artificial delay introduced due to udev-182
goes away:
[ 2.884657] usbcore: registered new interface driver em28xx
[ 2.884657] em28xx driver loaded
[ 3.123482] em28xx: init = 1, userspace_is_disabled = 0, needs firmware = 1
[ 3.123489] em28xx: New device WinTV HVR-980 @ 480 Mbps (2040:6513, interface 0, class 0)
[ 3.123491] em28xx: Audio Vendor Class interface 0 found
[ 3.123492] em28xx: Video interface 0 found
[ 3.123493] em28xx: DVB interface 0 found
[ 3.123633] em28xx #0: chip ID is em2882/em2883
[ 3.267680] em28xx #0: i2c eeprom 00: 1a eb 67 95 40 20 13 65 d0 12 5c 03 82 1e
[ 3.283034] em28xx #0: i2c eeprom 10: 00 00 24 57 66 07 01 00 00 00 00 00 00 00 00 00
[ 3.291857] em28xx #0: i2c eeprom 20: 46 00 01 00 f0 10 02 00 b8 00 00 00 5b 1c 00 00
[ 3.300682] em28xx #0: i2c eeprom 30: 00 00 20 40 20 80 02 20
[ 3.315397] em28xx #0: i2c eeprom 40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 3.324263] em28xx #0: i2c eeprom 50: 00 00 00 00 00 00
[ 3.339330] em28xx #0: i2c eeprom 60: 00 00 00 00 00 00 00 00 00 00 18 03 34 00 30 00
[ 3.348164] em28xx #0: i2c eeprom 70: 32 00 38 00 34 00 34 00 39 00 30 00 31 00 38 00
[ 3.356996] em28xx #0: i2c eeprom 80: 00 00 1e 03 57 00 69 00 6e 00 54 00 56 00 20 00
[ 3.365834] em28xx #0: i2c eeprom 90: 48 00 56 00 52 00 2d 00 39 00 38 00 30 00 00 00
[ 3.371533] em28xx #0: i2c eeprom a0: 84 12 00 00 05 50 1a 7f d4 78 23 b1 fe d0 18 85
[ 3.371537] em28xx #0: i2c eeprom b0: ff 00 00 00 04 84 0a 00 01 01 20 77 00 40 fa 40
[ 3.371540] em28xx #0: i2c eeprom c0: 1d f0 74 02 01 00 01 79 4f 00 00 00 00 00 00 00
[ 3.371544] em28xx #0: i2c eeprom d0: 84 12 00 00 05 50 1a 7f d4 78 23 b1 fe d0 18 85
[ 3.371547] em28xx #0: i2c eeprom e0: ff 00 00 00 04 84 0a 00 01 01 20 77 00 40 fa 40
[ 3.371551] em28xx #0: i2c eeprom f0: 1d f0 74 02 01 00 01 79 4f 00 00 00 00 00 00 00
[ 3.371556] em28xx #0: EEPROM ID= 0x9567eb1a, EEPROM hash = 0x994b2bdd
[ 3.371557] em28xx #0: EEPROM info:
[ 3.371558] em28xx #0: AC97 audio (5 sample rates)
[ 3.371558] em28xx #0: 500mA max power
[ 3.371560] em28xx #0: Table at 0x24, strings=0x1e82, 0x186a, 0x0000
[ 3.371562] em28xx #0: Identified as Hauppauge WinTV HVR 950 (card=16)
[ 3.487464] tvp5150 0-005c: chip found @ 0xb8 (em28xx #0)
[ 3.814980] em28xx #0: Config register raw data: 0xd0
[ 3.820851] em28xx #0: AC97 vendor ID = 0xffffffff
[ 3.826129] em28xx #0: AC97 features = 0x6a90
[ 3.830561] em28xx #0: Empia 202 AC97 audio processor detected
[ 3.996943] em28xx #0: v4l2 driver version 0.1.3
[ 4.078987] em28xx #0: V4L2 video device registered as video0
[ 4.078989] em28xx #0: V4L2 VBI device registered as vbi0
[ 4.137199] em28xx #0: em28xx #0/2: xc3028 attached
[ 4.173927] DVB: registering new adapter (em28xx #0)
[ 4.188846] em28xx #0: Successfully loaded em28xx-dvb
In other words, only the .probe() that is called during usb_register() is affected
by this behavior. Subsequent device additions/removals aren't affected:
[ 8125.049183] xc2028 0-0061: destroying instance
[ 8127.217933] usb 1-6: new high-speed USB device number 3 using ehci_hcd
[ 8127.343456] usb 1-6: New USB device found, idVendor=2040, idProduct=6513
[ 8127.350144] usb 1-6: New USB device strings: Mfr=0, Product=1, SerialNumber=2
[ 8127.357261] usb 1-6: Product: WinTV HVR-980
[ 8127.361428] usb 1-6: SerialNumber: 4028449018
[ 8127.366176] em28xx: init = 1, userspace_is_disabled = 0, needs firmware = 1
[ 8127.373153] em28xx: New device WinTV HVR-980 @ 480 Mbps (2040:6513, interface 0, class 0)
[ 8127.381416] em28xx: Audio Vendor Class interface 0 found
[ 8127.386709] em28xx: Video interface 0 found
[ 8127.390879] em28xx: DVB interface 0 found
[ 8127.395049] em28xx #0: chip ID is em2882/em2883
[ 8127.542105] em28xx #0: i2c eeprom 00: 1a eb 67 95 40 20 13 65 d0 12 5c 03 82 1e 6a 18
[ 8127.550112] em28xx #0: i2c eeprom 10: 00 00 24 57 66 07 01 00 00 00 00 00 00 00 00 00
[ 8127.558090] em28xx #0: i2c eeprom 20: 46 00 01 00 f0 10 02 00 b8 00 00 00 5b 1c 00 00
[ 8127.566074] em28xx #0: i2c eeprom 30: 00 00 20 40 20 80 02 20 01 01 01 01 00 00 00 00
[ 8127.574065] em28xx #0: i2c eeprom 40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 8127.582050] em28xx #0: i2c eeprom 50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 8127.590037] em28xx #0: i2c eeprom 60: 00 00 00 00 00 00 00 00 00 00 18 03 34 00 30 00
[ 8127.598023] em28xx #0: i2c eeprom 70: 32 00 38 00 34 00 34 00 39 00 30 00 31 00 38 00
[ 8127.606008] em28xx #0: i2c eeprom 80: 00 00 1e 03 57 00 69 00 6e 00 54 00 56 00 20 00
[ 8127.613989] em28xx #0: i2c eeprom 90: 48 00 56 00 52 00 2d 00 39 00 38 00 30 00 00 00
[ 8127.621979] em28xx #0: i2c eeprom a0: 84 12 00 00 05 50 1a 7f d4 78 23 b1 fe d0 18 85
[ 8127.629967] em28xx #0: i2c eeprom b0: ff 00 00 00 04 84 0a 00 01 01 20 77 00 40 fa 40
[ 8127.637951] em28xx #0: i2c eeprom c0: 1d f0 74 02 01 00 01 79 4f 00 00 00 00 00 00 00
[ 8127.645938] em28xx #0: i2c eeprom d0: 84 12 00 00 05 50 1a 7f d4 78 23 b1 fe d0 18 85
[ 8127.653924] em28xx #0: i2c eeprom e0: ff 00 00 00 04 84 0a 00 01 01 20 77 00 40 fa 40
[ 8127.661912] em28xx #0: i2c eeprom f0: 1d f0 74 02 01 00 01 79 4f 00 00 00 00 00 00 00
[ 8127.669898] em28xx #0: EEPROM ID= 0x9567eb1a, EEPROM hash = 0x994b2bdd
[ 8127.676402] em28xx #0: EEPROM info:
[ 8127.679875] em28xx #0: AC97 audio (5 sample rates)
[ 8127.684648] em28xx #0: 500mA max power
[ 8127.688384] em28xx #0: Table at 0x24, strings=0x1e82, 0x186a, 0x0000
[ 8127.694714] em28xx #0: Identified as Hauppauge WinTV HVR 950 (card=16)
[ 8127.701218] tveeprom 0-0050: Hauppauge model 65201, rev A1C0, serial# 1917178
[ 8127.708327] tveeprom 0-0050: tuner model is Xceive XC3028 (idx 120, type 71)
[ 8127.715351] tveeprom 0-0050: TV standards PAL(B/G) PAL(I) PAL(D/D1/K) ATSC/DVB Digital (eeprom 0xd4)
[ 8127.724451] tveeprom 0-0050: audio processor is None (idx 0)
[ 8127.730090] tveeprom 0-0050: has radio
[ 8127.735621] tvp5150 0-005c: chip found @ 0xb8 (em28xx #0)
[ 8127.788094] tvp5150 0-005c: tvp5150am1 detected.
[ 8127.810607] tuner 0-0061: Tuner -1 found with type(s) Radio TV.
[ 8127.816574] xc2028 0-0061: creating new instance
[ 8127.821183] xc2028 0-0061: type set to XCeive xc2028/xc3028 tuner
>> if (em28xx_boards[id->driver_info].needs_firmware &&
>> - is_usermodehelp_disabled()) {
>> - printk_once(KERN_DEBUG DRIVER_NAME
>> - ": probe deferred for board %d.\n",
>> - (unsigned)id->driver_info);
>> + (!is_em28xx_initialized || is_usermodehelp_disabled())) {
>> + printk(KERN_DEBUG DRIVER_NAME
>> + ": probe deferred for board %d.\n",
>> + (unsigned)id->driver_info);
>> return -EPROBE_DEFER;
>> }
>>
>> @@ -3456,4 +3461,28 @@ static struct usb_driver em28xx_usb_driver = {
>> .id_table = em28xx_id_table,
>> };
>>
>> -module_usb_driver(em28xx_usb_driver);
>
> Hint, if you are removing this macro, you can almost be assured that you
> are doing something wrong :)
:)
Regards,
Mauro
next prev parent reply other threads:[~2012-06-26 21:21 UTC|newest]
Thread overview: 81+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-21 13:36 [PATCH] [media] drxk: change it to use request_firmware_nowait() Mauro Carvalho Chehab
2012-06-21 14:21 ` Devin Heitmueller
2012-06-21 15:09 ` Mauro Carvalho Chehab
2012-06-21 19:10 ` Mauro Carvalho Chehab
2012-06-22 14:11 ` Marko Ristola
2012-06-25 19:15 ` Antti Palosaari
2012-06-25 20:06 ` Mauro Carvalho Chehab
2012-06-25 20:47 ` Need of an ".async_probe()" type of callback at driver's core - Was: " Mauro Carvalho Chehab
2012-06-25 20:49 ` Mauro Carvalho Chehab
2012-06-25 22:33 ` Greg KH
2012-06-26 1:55 ` Mauro Carvalho Chehab
2012-06-26 19:34 ` [PATCH RFC 0/4] Defer probe() on em28xx when firmware load is required Mauro Carvalho Chehab
2012-06-26 19:34 ` [PATCH RFC 1/4] kmod: add a routine to return if usermode is disabled Mauro Carvalho Chehab
2012-06-26 20:38 ` Greg KH
2012-06-26 21:05 ` Mauro Carvalho Chehab
2012-06-26 19:34 ` [PATCH RFC 2/4] em28xx: defer probe() if userspace mode " Mauro Carvalho Chehab
2012-06-26 20:43 ` Greg KH
2012-06-26 21:30 ` Mauro Carvalho Chehab
2012-06-26 19:34 ` [PATCH RFC 3/4] em28xx: Workaround for new udev versions Mauro Carvalho Chehab
2012-06-26 20:40 ` Greg KH
2012-06-26 21:07 ` Mauro Carvalho Chehab
2012-06-26 21:56 ` Kay Sievers
2012-06-26 20:42 ` Greg KH
2012-06-26 21:21 ` Mauro Carvalho Chehab [this message]
2012-06-26 21:27 ` Greg KH
2012-06-26 22:01 ` Mauro Carvalho Chehab
2012-06-28 17:51 ` Mauro Carvalho Chehab
2012-06-26 19:34 ` [PATCH RFC 4/4] tuner-xc2028: tag the usual firmwares to help dracut Mauro Carvalho Chehab
2012-06-26 20:44 ` Greg KH
2012-06-26 21:34 ` Mauro Carvalho Chehab
2012-10-02 13:03 ` udev breakages - was: Re: Need of an ".async_probe()" type of callback at driver's core - Was: Re: [PATCH] [media] drxk: change it to use request_firmware_nowait() Mauro Carvalho Chehab
2012-10-02 16:33 ` Linus Torvalds
2012-10-02 21:03 ` Ivan Kalvachev
2012-10-02 22:37 ` Linus Torvalds
2012-10-03 22:15 ` Lucas De Marchi
2012-10-02 22:12 ` Greg KH
2012-10-02 22:23 ` Greg KH
2012-10-02 22:47 ` Linus Torvalds
2012-10-03 0:01 ` Jiri Kosina
2012-10-03 0:12 ` Linus Torvalds
2012-10-04 14:36 ` Jiri Kosina
2012-10-03 15:13 ` Mauro Carvalho Chehab
2012-10-03 16:38 ` Linus Torvalds
2012-10-03 17:00 ` Linus Torvalds
2012-10-03 17:09 ` Al Viro
2012-10-03 17:32 ` Linus Torvalds
2012-10-03 19:26 ` Al Viro
2012-10-04 0:57 ` udev breakages - Nix
2012-10-04 10:35 ` Nix
2012-10-03 19:50 ` udev breakages - was: Re: Need of an ".async_probe()" type of callback at driver's core - Was: Re: [PATCH] [media] drxk: change it to use request_firmware_nowait() Greg KH
2012-10-03 20:39 ` Linus Torvalds
2012-10-03 21:04 ` Kay Sievers
2012-10-03 21:05 ` Greg KH
2012-10-03 21:18 ` Kay Sievers
2012-10-03 21:45 ` Alan Cox
2012-10-03 21:58 ` Lucas De Marchi
2012-10-03 22:17 ` Linus Torvalds
2012-10-03 22:48 ` Andy Walls
2012-10-03 22:58 ` Linus Torvalds
2012-10-04 2:39 ` Kay Sievers
2012-10-04 17:29 ` udev breakages - Eric W. Biederman
2012-10-04 17:42 ` Greg KH
2012-10-04 19:17 ` Alan Cox
2012-10-10 3:19 ` Felipe Contreras
2012-10-10 16:08 ` Geert Uytterhoeven
2012-10-11 3:32 ` Eric W. Biederman
2012-10-04 13:39 ` udev breakages - was: Re: Need of an ".async_probe()" type of callback at driver's core - Was: Re: [PATCH] [media] drxk: change it to use request_firmware_nowait() Josh Boyer
2012-10-04 13:58 ` Greg KH
2012-10-03 22:53 ` Stephen Rothwell
2012-10-03 21:10 ` Andy Walls
2012-10-03 19:48 ` Access files from kernel Kirill A. Shutemov
2012-10-03 20:32 ` Linus Torvalds
[not found] ` <CACVXFVNTZmG+zTQNi9mCn9ynsCjkM084TmHKDcYYggtqLfhqNQ@mail.gmail.com>
2012-10-04 1:42 ` udev breakages - was: Re: Need of an ".async_probe()" type of callback at driver's core - Was: Re: [PATCH] [media] drxk: change it to use request_firmware_nowait() Linus Torvalds
2012-10-03 14:12 ` Mauro Carvalho Chehab
2012-10-03 14:36 ` Kay Sievers
2012-10-03 14:44 ` Linus Torvalds
2012-10-03 16:57 ` Greg KH
2012-10-03 17:24 ` Kay Sievers
2012-10-03 18:07 ` Linus Torvalds
2012-10-03 19:46 ` Mauro Carvalho Chehab
2012-06-29 8:26 ` Jean Delvare
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