| Message ID | 20170127145930.13055-1-ricardo.ribalda@gmail.com |
|---|---|
| State | Accepted |
| Headers | show |
Hi Ricardo, On ven., 2017-01-27 at 15:59 +0100, Ricardo Ribalda Delgado wrote: > Since '701dc207bf55 ("i2c: piix4: Avoid race conditions with IMC")' > we > are using the SMBSLVCNT register at offset 0x8. We need to request > it. > > Fixes: 701dc207bf55 ("i2c: piix4: Avoid race conditions with IMC") > Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> > --- > Please note, not tested on hardware. > drivers/i2c/busses/i2c-piix4.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c- > piix4.c > index e34d82e79b98..73cc6799cc59 100644 > --- a/drivers/i2c/busses/i2c-piix4.c > +++ b/drivers/i2c/busses/i2c-piix4.c > @@ -58,7 +58,7 @@ > #define SMBSLVDAT (0xC + piix4_smba) > > /* count for request_region */ > -#define SMBIOSIZE 8 > +#define SMBIOSIZE 9 > Are you certain that all supported devices have this extra register? > > /* PCI Address Constants */ > #define SMBBA 0x090 -- Jean Delvare SUSE L3 Support -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
> > /* count for request_region */ > > -#define SMBIOSIZE 8 > > +#define SMBIOSIZE 9 > > > > Are you certain that all supported devices have this extra register? Isn't it better to have a potentially unused register mapped than a potentially used register unmapped?
Hi Wolfram, On Sat, 28 Jan 2017 12:00:21 +0100, Wolfram Sang wrote: > > > > /* count for request_region */ > > > -#define SMBIOSIZE 8 > > > +#define SMBIOSIZE 9 > > > > Are you certain that all supported devices have this extra register? > > Isn't it better to have a potentially unused register mapped than a > potentially used register unmapped? My concern is that the region request could fail due to a conflict with another device, if the physical I/O region is only 8 and we try to request 9.
Hi Jean and Wolfram On Sat, Jan 28, 2017 at 12:13 PM, Jean Delvare <jdelvare@suse.de> wrote: > Hi Wolfram, > > On Sat, 28 Jan 2017 12:00:21 +0100, Wolfram Sang wrote: >> >> > > /* count for request_region */ >> > > -#define SMBIOSIZE 8 >> > > +#define SMBIOSIZE 9 >> > >> > Are you certain that all supported devices have this extra register? >> >> Isn't it better to have a potentially unused register mapped than a >> potentially used register unmapped We have been "lucky" that it is a ioport and not a mmap region, otherwise we would have seen a nice oops :). > > My concern is that the region request could fail due to a conflict with > another device, if the physical I/O region is only 8 and we try to > request 9. I do not think that this is the case, if you check the top of the file you can see how there are many other definitions for registers. I expect that SMBIOSIZE=8 is just the original author being conservative. Of course I cannot say that there is one platform where one extra ioport can cause a conflict, but I believe that we must request all the ports that we will use. Regards! > > -- > Jean Delvare > SUSE L3 Support
Hi Ricardo, Wolfram, On Fri, 27 Jan 2017 15:59:30 +0100, Ricardo Ribalda Delgado wrote: > Since '701dc207bf55 ("i2c: piix4: Avoid race conditions with IMC")' we > are using the SMBSLVCNT register at offset 0x8. We need to request it. > > Fixes: 701dc207bf55 ("i2c: piix4: Avoid race conditions with IMC") > Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> > --- > Please note, not tested on hardware. > drivers/i2c/busses/i2c-piix4.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c > index e34d82e79b98..73cc6799cc59 100644 > --- a/drivers/i2c/busses/i2c-piix4.c > +++ b/drivers/i2c/busses/i2c-piix4.c > @@ -58,7 +58,7 @@ > #define SMBSLVDAT (0xC + piix4_smba) > > /* count for request_region */ > -#define SMBIOSIZE 8 > +#define SMBIOSIZE 9 > > /* PCI Address Constants */ > #define SMBBA 0x090 I checked all the datasheets I have access to, and it should be good. Signed-off-by: Jean Delvare <jdelvare@suse.de>
On Fri, Jan 27, 2017 at 03:59:30PM +0100, Ricardo Ribalda Delgado wrote: > Since '701dc207bf55 ("i2c: piix4: Avoid race conditions with IMC")' we > are using the SMBSLVCNT register at offset 0x8. We need to request it. > > Fixes: 701dc207bf55 ("i2c: piix4: Avoid race conditions with IMC") > Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Applied to for-current, thanks!
diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c index e34d82e79b98..73cc6799cc59 100644 --- a/drivers/i2c/busses/i2c-piix4.c +++ b/drivers/i2c/busses/i2c-piix4.c @@ -58,7 +58,7 @@ #define SMBSLVDAT (0xC + piix4_smba) /* count for request_region */ -#define SMBIOSIZE 8 +#define SMBIOSIZE 9 /* PCI Address Constants */ #define SMBBA 0x090
Since '701dc207bf55 ("i2c: piix4: Avoid race conditions with IMC")' we are using the SMBSLVCNT register at offset 0x8. We need to request it. Fixes: 701dc207bf55 ("i2c: piix4: Avoid race conditions with IMC") Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> --- Please note, not tested on hardware. drivers/i2c/busses/i2c-piix4.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)