lkml.org 
[lkml]   [2015]   [Jun]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2] i2c: designware: Avoid unnecessary resuming during system suspend
On Wed, May 20, 2015 at 10:33:13PM +0800, Jisheng Zhang wrote:
> Commit 1fc2fe204cb9 ("i2c: designware: Add runtime PM hooks") adds
> runtime pm support using the same ops for system pm and runtime pm.
> When suspend to ram, the i2c host may have been runtime suspended, thus
> i2c_dw_disable() hangs.
>
> Previously, I fixed this issue by separating ops for system pm and
> runtime pm, then in the system suspend/resume path, runtime pm apis are
> used to ensure the device is at correct state.
>
> But as Mika Westerberg pointed out: it sounds a bit silly to resume the
> device just because you want to call i2c_dw_disable() for it before
> suspending again. He then suggested an elegant solution which keeps the
> device runtime suspended during system suspend with the help of
> 'dev->power.direct_complete'. This patch adopted this solution, and in
> fact Mika provided the main code.
>
> Signed-off-by: Jisheng Zhang <jszhang@marvell.com>

Fixed the 80 char thingie and applied to for-next, thanks!

[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2015-06-02 20:21    [W:0.072 / U:0.084 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site