[PATCH] i2c-i801: Clear only status bits in HST_STS after waiting for INTR

[PATCH] i2c-i801: Clear only status bits in HST_STS after waiting for INTR

[Daniel Kurtz]

Writing back the whole status register could clear unwanted bits.
In particular, it could clear the "INUSE_STS" bit, which is a
'hardware semaphore', that might be useful to use some day.
To prepare for this, let's ban writing back the whole status to register
HST_STS, of which this is the only instance.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Reported-by: Jean Delvare <khali@linux-fr.org>
---
 drivers/i2c/busses/i2c-i801.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index ae2945a..7443990 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -301,7 +301,7 @@ static void i801_wait_hwpec(struct i801_priv *priv)
 	if (timeout > MAX_RETRIES)
 		dev_dbg(&priv->pci_dev->dev, "PEC Timeout!\n");
 
-	outb_p(status, SMBHSTSTS(priv));
+	outb_p(status & STATUS_FLAGS, SMBHSTSTS(priv));
 }
 
 static int i801_block_transaction_by_block(struct i801_priv *priv,
-- 
1.7.7.3

Re: [PATCH] i2c-i801: Clear only status bits in HST_STS after waiting for INTR

[Jean Delvare]

On Thu, 28 Jun 2012 16:59:30 +0800, Daniel Kurtz wrote:
> Writing back the whole status register could clear unwanted bits.
> In particular, it could clear the "INUSE_STS" bit, which is a
> 'hardware semaphore', that might be useful to use some day.
> To prepare for this, let's ban writing back the whole status to register
> HST_STS, of which this is the only instance.
> 
> Signed-off-by: Daniel Kurtz <djkurtz-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
> Reported-by: Jean Delvare <khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org>
> ---
>  drivers/i2c/busses/i2c-i801.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
> index ae2945a..7443990 100644
> --- a/drivers/i2c/busses/i2c-i801.c
> +++ b/drivers/i2c/busses/i2c-i801.c
> @@ -301,7 +301,7 @@ static void i801_wait_hwpec(struct i801_priv *priv)
>  	if (timeout > MAX_RETRIES)
>  		dev_dbg(&priv->pci_dev->dev, "PEC Timeout!\n");
>  
> -	outb_p(status, SMBHSTSTS(priv));
> +	outb_p(status & STATUS_FLAGS, SMBHSTSTS(priv));
>  }
>  
>  static int i801_block_transaction_by_block(struct i801_priv *priv,

Applied, thanks.

-- 
Jean Delvare