Re: SYSFS: need a noncaching read

2007-09-17 Thread Tejun Heo
Greg KH wrote: > On Wed, Sep 12, 2007 at 07:32:07AM +0200, Robert Schwebel wrote: >> On Tue, Sep 11, 2007 at 11:43:17AM +0200, Heiko Schocher wrote: >>> I have developed a device driver and use the sysFS to export some >>> registers to userspace. >> Uuuh, uggly. Don't do that. Device drivers are th

Re: SYSFS: need a noncaching read

2007-09-12 Thread Neil Brown
On Wednesday September 12, [EMAIL PROTECTED] wrote: > On Wednesday 12 September 2007 20:01, Greg KH wrote: > > On Wed, Sep 12, 2007 at 07:32:07AM +0200, Robert Schwebel wrote: > > > On Tue, Sep 11, 2007 at 11:43:17AM +0200, Heiko Schocher wrote: > > > > I have developed a device driver and use the

Re: SYSFS: need a noncaching read

2007-09-12 Thread Nick Piggin
On Wednesday 12 September 2007 20:01, Greg KH wrote: > On Wed, Sep 12, 2007 at 07:32:07AM +0200, Robert Schwebel wrote: > > On Tue, Sep 11, 2007 at 11:43:17AM +0200, Heiko Schocher wrote: > > > I have developed a device driver and use the sysFS to export some > > > registers to userspace. > > > > U

Re: SYSFS: need a noncaching read

2007-09-12 Thread Heiko Schocher
Hello Greg, Am Mittwoch, den 12.09.2007, 04:39 -0700 schrieb Greg KH: > > > Do an lseek back to 0 and then re-read, you will get called in your > > > driver again. > > > > No thats not true. I thought this too, but if I make a: > > > > seek (fd, 0L, SEEK_SET); > > > > in Userspace, there is no

Re: SYSFS: need a noncaching read

2007-09-12 Thread Greg KH
On Wed, Sep 12, 2007 at 01:13:32PM +0200, Heiko Schocher wrote: > Hello Greg > > Am Mittwoch, den 12.09.2007, 03:01 -0700 schrieb Greg KH: > > On Wed, Sep 12, 2007 at 07:32:07AM +0200, Robert Schwebel wrote: > > > On Tue, Sep 11, 2007 at 11:43:17AM +0200, Heiko Schocher wrote: > > > > I have devel

Re: SYSFS: need a noncaching read

2007-09-12 Thread Heiko Schocher
Hello Greg Am Mittwoch, den 12.09.2007, 03:01 -0700 schrieb Greg KH: > On Wed, Sep 12, 2007 at 07:32:07AM +0200, Robert Schwebel wrote: > > On Tue, Sep 11, 2007 at 11:43:17AM +0200, Heiko Schocher wrote: > > > I have developed a device driver and use the sysFS to export some > > > registers to use

Re: SYSFS: need a noncaching read

2007-09-12 Thread Greg KH
On Wed, Sep 12, 2007 at 07:32:07AM +0200, Robert Schwebel wrote: > On Tue, Sep 11, 2007 at 11:43:17AM +0200, Heiko Schocher wrote: > > I have developed a device driver and use the sysFS to export some > > registers to userspace. > > Uuuh, uggly. Don't do that. Device drivers are there to abstract

Re: SYSFS: need a noncaching read

2007-09-11 Thread Robert Schwebel
On Tue, Sep 11, 2007 at 11:43:17AM +0200, Heiko Schocher wrote: > I have developed a device driver and use the sysFS to export some > registers to userspace. Uuuh, uggly. Don't do that. Device drivers are there to abstract things, not to play around with registers from userspace. > I opened the s

Re: SYSFS: need a noncaching read

2007-09-11 Thread Michael Ellerman
On Wed, 2007-09-12 at 12:05 +1000, David Gibson wrote: > On Tue, Sep 11, 2007 at 11:43:17AM +0200, Heiko Schocher wrote: > > Hello, > > > > I have developed a device driver and use the sysFS to export some > > registers to userspace. I opened the sysFS File for one register and did > > some reads

Re: SYSFS: need a noncaching read

2007-09-11 Thread David Gibson
On Tue, Sep 11, 2007 at 11:43:17AM +0200, Heiko Schocher wrote: > Hello, > > I have developed a device driver and use the sysFS to export some > registers to userspace. I opened the sysFS File for one register and did > some reads from this File, but I alwas becoming the same value from the > regi

SYSFS: need a noncaching read

2007-09-11 Thread Heiko Schocher
Hello, I have developed a device driver and use the sysFS to export some registers to userspace. I opened the sysFS File for one register and did some reads from this File, but I alwas becoming the same value from the register, whats not OK, because they are changing. So I found out that the sysFS