[i2c] [PATCH] I2C && DVB: fix recursive locking lockped warning in i2c_transfer()
jikos at jikos.cz
Wed Oct 18 16:50:57 CEST 2006
On Wed, 18 Oct 2006, Jean Delvare wrote:
> OK, I've now read this documentation file, things are now somewhat
> clearer in my head. I had heard about the "lock class" theory before but
> didn't remember all the details. I understand the good idea behind this
Thanks for looking at it.
> I just took a look at the usb code to see how they have been dealing
> with it. They do have a structure member to store the lock level
> (usb_device.level), it's included unconditionally. In the USB case, the
> nested locking is only needed to handle power management, while for I2C
> it is needed to even use the devices, but this shouldn't make much
> difference. So it would probably be OK to do the same in the i2c
> subsystem, which actually means taking your patch or something very
I agree, thanks.
> OK, after some more thought, I understand your point and take back my
> peremptory comment above ;)
> I'd like to have 2 different patches:
> 1* One adding the "functionality" to i2c-core. I propose to name the
> extra structure member "level" and to make it an u8, as was done in the
> usb subsystem, for consistency. This patch would go in my i2c tree.
Thanks, will send you a patch probably later today.
> 2* One changing the affected DVB drivers to make use of it. This patch
> would go in the v4l-dvb tree. I'd let the driver and media/video
> subsystem maintainers deal with it.
The only callpath which needs fixing I am currently aware of is the one I
have provided patch for in the previous mail. So I will fix this one, and
provide it to you in a separate patch.
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