[PATCH 3/7] i2c: designware-baytrail: Take punit lock on bus acquire

[Andy Shevchenko]

On Sun, 2017-01-08 at 14:44 +0100, Hans de Goede wrote:
> Take the punit lock to stop others from accessing the punit while the
> pmic i2c bus is in use. This is necessary because accessing the punit
> from the kernel may result in the punit trying to access the pmic i2c
> bus, which results in a hang when it happens while we own the pmic i2c
> bus semaphore.
> 
> BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=155241
> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
> Tested-by: tagorereddy <tagore.chandan at gmail.com>
> ---
>  drivers/i2c/busses/i2c-designware-baytrail.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/i2c/busses/i2c-designware-baytrail.c
> b/drivers/i2c/busses/i2c-designware-baytrail.c
> index 3effc9a..cf7a2a0 100644
> --- a/drivers/i2c/busses/i2c-designware-baytrail.c
> +++ b/drivers/i2c/busses/i2c-designware-baytrail.c
> 

> @@ -62,6 +62,8 @@ static void reset_semaphore(struct dw_i2c_dev *dev)

> +	iosf_mbi_punit_unlock();

> @@ -79,6 +81,8 @@ static int baytrail_i2c_acquire(struct dw_i2c_dev
> +	iosf_mbi_punit_lock();

For me it looks a bit asymmetrical.

Can we use acquire()/release()?

-- 
Andy Shevchenko <andriy.shevchenko at linux.intel.com>
Intel Finland Oy