2012-06-28 08:59:37

by Daniel Kurtz

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

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 <[email protected]>
Reported-by: Jean Delvare <[email protected]>
---
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

2012-06-28 12:52:24

by Jean Delvare

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

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 <[email protected]>
> Reported-by: Jean Delvare <[email protected]>
> ---
> 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