| Message ID | cefbeb76-5f7f-036b-fa0e-1e339d261c35@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] i2c: i801: Ensure that SMBHSTSTS_INUSE_STS is cleared when leaving i801_access | expand |
On 06/06/2021 22.55, Heiner Kallweit wrote: > As explained in [0] currently we may leave SMBHSTSTS_INUSE_STS set, > thus potentially breaking ACPI/BIOS usage of the SMBUS device. > > Seems patch [0] needs a little bit more of review effort, therefore > I'd suggest to apply a part of it as quick win. Just clearing > SMBHSTSTS_INUSE_STS when leaving i801_access() should fix the > referenced issue and leaves more time for discussing a more > sophisticated locking handling. > out: > + /* Unlock the SMBus device for use by BIOS/ACPI */ > + outb_p(SMBHSTSTS_INUSE_STS, SMBHSTSTS(priv)); > + > pm_runtime_mark_last_busy(&priv->pci_dev->dev); Yup, I was thinking of suggesting just this part if the rest of the patch were deemed more controversial. Thanks :) Reviewed-by: Hector Martin <marcan@marcan.st> -- Hector Martin (marcan@marcan.st) Public Key: https://mrcn.st/pub
Hi Heiner, Hector, On Sun, 6 Jun 2021 15:55:55 +0200, Heiner Kallweit wrote: > As explained in [0] currently we may leave SMBHSTSTS_INUSE_STS set, > thus potentially breaking ACPI/BIOS usage of the SMBUS device. > > Seems patch [0] needs a little bit more of review effort, therefore > I'd suggest to apply a part of it as quick win. Just clearing > SMBHSTSTS_INUSE_STS when leaving i801_access() should fix the > referenced issue and leaves more time for discussing a more > sophisticated locking handling. > > [0] https://www.spinics.net/lists/linux-i2c/msg51558.html > > Fixes: 01590f361e94 ("i2c: i801: Instantiate SPD EEPROMs automatically") > Cc: stable@vger.kernel.org > Suggested-by: Hector Martin <marcan@marcan.st> > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> > --- > v2: > - add proper stable tag > --- > drivers/i2c/busses/i2c-i801.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c > index c7d96cf5e..ab3470e77 100644 > --- a/drivers/i2c/busses/i2c-i801.c > +++ b/drivers/i2c/busses/i2c-i801.c > @@ -948,6 +948,9 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr, > } > > out: > + /* Unlock the SMBus device for use by BIOS/ACPI */ > + outb_p(SMBHSTSTS_INUSE_STS, SMBHSTSTS(priv)); > + > pm_runtime_mark_last_busy(&priv->pci_dev->dev); > pm_runtime_put_autosuspend(&priv->pci_dev->dev); > mutex_unlock(&priv->acpi_lock); Good idea. Reviewed-by: Jean Delvare <jdelvare@suse.de> Tested-by: Jean Delvare <jdelvare@suse.de> Hector, can you please rebase your patch on top of this one? I'll review it later when I have more time to allocate to the task. Thanks, -- Jean Delvare SUSE L3 Support
On Sun, Jun 06, 2021 at 03:55:55PM +0200, Heiner Kallweit wrote: > As explained in [0] currently we may leave SMBHSTSTS_INUSE_STS set, > thus potentially breaking ACPI/BIOS usage of the SMBUS device. > > Seems patch [0] needs a little bit more of review effort, therefore > I'd suggest to apply a part of it as quick win. Just clearing > SMBHSTSTS_INUSE_STS when leaving i801_access() should fix the > referenced issue and leaves more time for discussing a more > sophisticated locking handling. > > [0] https://www.spinics.net/lists/linux-i2c/msg51558.html > > Fixes: 01590f361e94 ("i2c: i801: Instantiate SPD EEPROMs automatically") > Cc: stable@vger.kernel.org > Suggested-by: Hector Martin <marcan@marcan.st> > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Applied to for-current, thanks!
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index c7d96cf5e..ab3470e77 100644 --- a/drivers/i2c/busses/i2c-i801.c +++ b/drivers/i2c/busses/i2c-i801.c @@ -948,6 +948,9 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr, } out: + /* Unlock the SMBus device for use by BIOS/ACPI */ + outb_p(SMBHSTSTS_INUSE_STS, SMBHSTSTS(priv)); + pm_runtime_mark_last_busy(&priv->pci_dev->dev); pm_runtime_put_autosuspend(&priv->pci_dev->dev); mutex_unlock(&priv->acpi_lock);
As explained in [0] currently we may leave SMBHSTSTS_INUSE_STS set, thus potentially breaking ACPI/BIOS usage of the SMBUS device. Seems patch [0] needs a little bit more of review effort, therefore I'd suggest to apply a part of it as quick win. Just clearing SMBHSTSTS_INUSE_STS when leaving i801_access() should fix the referenced issue and leaves more time for discussing a more sophisticated locking handling. [0] https://www.spinics.net/lists/linux-i2c/msg51558.html Fixes: 01590f361e94 ("i2c: i801: Instantiate SPD EEPROMs automatically") Cc: stable@vger.kernel.org Suggested-by: Hector Martin <marcan@marcan.st> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> --- v2: - add proper stable tag --- drivers/i2c/busses/i2c-i801.c | 3 +++ 1 file changed, 3 insertions(+)