The standard IO regions are already reserved by the platform code on most MIPS
devices(malta, cobalt, sni). The Commit 197a1e96c8be5b6005145af3a4c0e45e2d651444
("Input: i8042-io - fix up region handling on MIPS") introduced a bug on these
MIPS platforms causing i8042 driver to fail when trying to reserve IO ports.
Prior to the above mentioned commit request_region is skipped on MIPS but
release_region is called.
This patch reverts commit 197a1e96c8be5b6005145af3a4c0e45e2d651444 and also
avoids calling release_region for MIPS.
Signed-off-by: Raghu Gandham <[email protected]>
Reviewed-by: Steven J. Hill <[email protected]>
---
drivers/input/serio/i8042-io.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/input/serio/i8042-io.h b/drivers/input/serio/i8042-io.h
index a5eed2a..a09bb72 100644
--- a/drivers/input/serio/i8042-io.h
+++ b/drivers/input/serio/i8042-io.h
@@ -76,7 +76,7 @@ static inline int i8042_platform_init(void)
if (check_legacy_ioport(I8042_DATA_REG))
return -ENODEV;
#endif
-#if !defined(__sh__) && !defined(__alpha__)
+#if !defined(__sh__) && !defined(__alpha__) && !defined(__mips__)
if (!request_region(I8042_DATA_REG, 16, "i8042"))
return -EBUSY;
#endif
@@ -87,7 +87,7 @@ static inline int i8042_platform_init(void)
static inline void i8042_platform_exit(void)
{
-#if !defined(__sh__) && !defined(__alpha__)
+#if !defined(__sh__) && !defined(__alpha__) && !defined(__mips__)
release_region(I8042_DATA_REG, 16);
#endif
}
--
1.8.5.2
Hi Raghu,
On Sat, Jan 25, 2014 at 11:01:54AM -0800, Raghu Gandham wrote:
> The standard IO regions are already reserved by the platform code on most MIPS
> devices(malta, cobalt, sni). The Commit 197a1e96c8be5b6005145af3a4c0e45e2d651444
> ("Input: i8042-io - fix up region handling on MIPS") introduced a bug on these
> MIPS platforms causing i8042 driver to fail when trying to reserve IO ports.
> Prior to the above mentioned commit request_region is skipped on MIPS but
> release_region is called.
>
> This patch reverts commit 197a1e96c8be5b6005145af3a4c0e45e2d651444 and also
> avoids calling release_region for MIPS.
The problem is that IO regions are reserved on _most_, but not _all_
devices. MIPS should figure out what they want to do with i8042
registers and be consistent on all devices.
I do not want to apply this patch because it will be breaking devices
using the other configuration.
Thanks.
--
Dmitry
Hi Dmitry,
>
> On Sat, Jan 25, 2014 at 11:01:54AM -0800, Raghu Gandham wrote:
> > The standard IO regions are already reserved by the platform code on
> > most MIPS devices(malta, cobalt, sni). The Commit
> > 197a1e96c8be5b6005145af3a4c0e45e2d651444
> > ("Input: i8042-io - fix up region handling on MIPS") introduced a bug
> > on these MIPS platforms causing i8042 driver to fail when trying to reserve
> IO ports.
> > Prior to the above mentioned commit request_region is skipped on MIPS
> > but release_region is called.
> >
> > This patch reverts commit 197a1e96c8be5b6005145af3a4c0e45e2d651444
> and
> > also avoids calling release_region for MIPS.
>
> The problem is that IO regions are reserved on _most_, but not _all_ devices.
> MIPS should figure out what they want to do with i8042 registers and be
> consistent on all devices.
Please examine the attached patch which went upstream in April of 2004. Since then
it had been a convention not to call request_region routine in i8042 for MIPS. The
attached patch had a glitch that it guarded request_region in i8042-io.h but skipped
guarding release_region in i8042-io.h. I believe that the issue Aaro saw was due to this
glitch. Below is the error quoted in Aaro's commit message.
[ 2.112000] Trying to free nonexistent resource <0000000000000060-000000000000006f>
My patch reinstates the convention followed on MIPS devices along with fixing Aaro's issue.
Thanks,
Raghu
On Mon, Jan 27, 2014 at 12:32:36AM +0000, Raghu Gandham wrote:
> Hi Dmitry,
>
> >
> > On Sat, Jan 25, 2014 at 11:01:54AM -0800, Raghu Gandham wrote:
> > > The standard IO regions are already reserved by the platform code on
> > > most MIPS devices(malta, cobalt, sni). The Commit
> > > 197a1e96c8be5b6005145af3a4c0e45e2d651444
> > > ("Input: i8042-io - fix up region handling on MIPS") introduced a bug
> > > on these MIPS platforms causing i8042 driver to fail when trying to reserve
> > IO ports.
> > > Prior to the above mentioned commit request_region is skipped on MIPS
> > > but release_region is called.
> > >
> > > This patch reverts commit 197a1e96c8be5b6005145af3a4c0e45e2d651444
> > and
> > > also avoids calling release_region for MIPS.
> >
> > The problem is that IO regions are reserved on _most_, but not _all_ devices.
> > MIPS should figure out what they want to do with i8042 registers and be
> > consistent on all devices.
>
> Please examine the attached patch which went upstream in April of 2004. Since then
> it had been a convention not to call request_region routine in i8042 for MIPS. The
> attached patch had a glitch that it guarded request_region in i8042-io.h but skipped
> guarding release_region in i8042-io.h. I believe that the issue Aaro saw was due to this
> glitch. Below is the error quoted in Aaro's commit message.
>
> [ 2.112000] Trying to free nonexistent resource <0000000000000060-000000000000006f>
>
> My patch reinstates the convention followed on MIPS devices along with fixing Aaro's issue.
I assume that Aaro did test his patch and on his box request_region()
succeeds. That would indicate that various MIPS sub-arches still not
settled on the topic.
Aaro?
Thanks.
--
Dmitry
Hi,
On Sun, Jan 26, 2014 at 10:56:38PM -0800, Dmitry Torokhov wrote:
> On Mon, Jan 27, 2014 at 12:32:36AM +0000, Raghu Gandham wrote:
> > > On Sat, Jan 25, 2014 at 11:01:54AM -0800, Raghu Gandham wrote:
> > > > The standard IO regions are already reserved by the platform code on
> > > > most MIPS devices(malta, cobalt, sni). The Commit
> > > > 197a1e96c8be5b6005145af3a4c0e45e2d651444
> > > > ("Input: i8042-io - fix up region handling on MIPS") introduced a bug
> > > > on these MIPS platforms causing i8042 driver to fail when trying to
> > > > reserve IO ports.
> > > > Prior to the above mentioned commit request_region is skipped on MIPS
> > > > but release_region is called.
> > > >
> > > > This patch reverts commit 197a1e96c8be5b6005145af3a4c0e45e2d651444
> > > > and also avoids calling release_region for MIPS.
> > >
> > > The problem is that IO regions are reserved on _most_, but not _all_
> > > devices.
> > > MIPS should figure out what they want to do with i8042 registers and be
> > > consistent on all devices.
> >
> > Please examine the attached patch which went upstream in April of 2004.
> > Since then it had been a convention not to call request_region routine in
> > i8042 for MIPS. The attached patch had a glitch that it guarded
> > request_region in i8042-io.h but skipped guarding release_region in
> > i8042-io.h. I believe that the issue Aaro saw was due to this
> > glitch. Below is the error quoted in Aaro's commit message.
> >
> > [ 2.112000] Trying to free nonexistent resource <0000000000000060-000000000000006f>
> >
> > My patch reinstates the convention followed on MIPS devices along with
> > fixing Aaro's issue.
>
> I assume that Aaro did test his patch and on his box request_region()
> succeeds. That would indicate that various MIPS sub-arches still not
> settled on the topic.
request_region() succeeds on Loongson and OCTEON.
On OCTEONs without PCI, request_region() will fail which is correct as
there is no I/O space.
I wasn't aware of that 2004 patch (it pre-dates GIT history of mainline
Linux). Why the regions are already reserved by the platform code?
A.
Hi Aaro,
>
> On Sun, Jan 26, 2014 at 10:56:38PM -0800, Dmitry Torokhov wrote:
> > On Mon, Jan 27, 2014 at 12:32:36AM +0000, Raghu Gandham wrote:
> > > > On Sat, Jan 25, 2014 at 11:01:54AM -0800, Raghu Gandham wrote:
> > > > > The standard IO regions are already reserved by the platform
> > > > > code on most MIPS devices(malta, cobalt, sni). The Commit
> > > > > 197a1e96c8be5b6005145af3a4c0e45e2d651444
> > > > > ("Input: i8042-io - fix up region handling on MIPS") introduced
> > > > > a bug on these MIPS platforms causing i8042 driver to fail when
> > > > > trying to reserve IO ports.
> > > > > Prior to the above mentioned commit request_region is skipped on
> > > > > MIPS but release_region is called.
> > > > >
> > > > > This patch reverts commit
> > > > > 197a1e96c8be5b6005145af3a4c0e45e2d651444
> > > > > and also avoids calling release_region for MIPS.
> > > >
> > > > The problem is that IO regions are reserved on _most_, but not
> > > > _all_ devices.
> > > > MIPS should figure out what they want to do with i8042 registers
> > > > and be consistent on all devices.
> > >
> > > Please examine the attached patch which went upstream in April of 2004.
> > > Since then it had been a convention not to call request_region
> > > routine in
> > > i8042 for MIPS. The attached patch had a glitch that it guarded
> > > request_region in i8042-io.h but skipped guarding release_region in
> > > i8042-io.h. I believe that the issue Aaro saw was due to this
> > > glitch. Below is the error quoted in Aaro's commit message.
> > >
> > > [ 2.112000] Trying to free nonexistent resource <0000000000000060-
> 000000000000006f>
> > >
> > > My patch reinstates the convention followed on MIPS devices along
> > > with fixing Aaro's issue.
> >
> > I assume that Aaro did test his patch and on his box request_region()
> > succeeds. That would indicate that various MIPS sub-arches still not
> > settled on the topic.
>
> request_region() succeeds on Loongson and OCTEON.
This would mean that before your patch in oct of 2012, Loongson and Octeon
were not reserving the IO space for i8042.
>
> On OCTEONs without PCI, request_region() will fail which is correct as there
> is no I/O space.
>
> I wasn't aware of that 2004 patch (it pre-dates GIT history of mainline Linux).
> Why the regions are already reserved by the platform code?
The only information I have is the comment before request_region in i8042-io.h that
touching data register on some platforms is flaky. If your patch was primarily aimed at
addressing the error message from release_region, the current patch I uploaded should
also take care of it too.
Thanks,
Raghu