RE: [PATCH v0 linux master] i2c/busses: Avoid i2c interrupt status clear race condition.

2020-05-04 Thread Ryan Chen
> In AST2600 there have a slow peripheral bus between CPU and i2c > controller. > Therefore GIC i2c interrupt status clear have delay timing, when CPU > issue write clear i2c controller interrupt status. > To avoid this issue, the driver need have read after write clear at > i2c ISR. > >

RE: [PATCH v0 linux master] i2c/busses: Avoid i2c interrupt status clear race condition.

2020-05-04 Thread Ryan Chen
> > And is there maybe a Fixes: tag for it? > > [Ryan Chen] Yes it is a fix patch. > > I meant this (from submitting-patches.rst): >It fixes the original implementation of the driver basically. It's just a >classic posted-write fix. The write to clear the pending interrupt is >asynchronous, so

Re: [PATCH v0 linux master] i2c/busses: Avoid i2c interrupt status clear race condition.

2020-04-30 Thread Wolfram Sang
On Wed, Apr 29, 2020 at 11:37:37AM +0800, ryan_chen wrote: > In AST2600 there have a slow peripheral bus between CPU > and i2c controller. > Therefore GIC i2c interrupt status clear have delay timing, > when CPU issue write clear i2c controller interrupt status. > To avoid this issue, the driver

Re: [PATCH v0 linux master] i2c/busses: Avoid i2c interrupt status clear race condition.

2020-04-30 Thread Benjamin Herrenschmidt
On Wed, 2020-04-29 at 11:03 +0200, Wolfram Sang wrote: > > And is there maybe a Fixes: tag for it? > > [Ryan Chen] Yes it is a fix patch. > > I meant this (from submitting-patches.rst): It fixes the original implementation of the driver basically. It's just a classic posted-write fix. The write

Re: [PATCH v0 linux master] i2c/busses: Avoid i2c interrupt status clear race condition.

2020-04-30 Thread Benjamin Herrenschmidt
On Wed, 2020-04-29 at 11:37 +0800, ryan_chen wrote: > In AST2600 there have a slow peripheral bus between CPU > and i2c controller. > Therefore GIC i2c interrupt status clear have delay timing, > when CPU issue write clear i2c controller interrupt status. > To avoid this issue, the driver need

Re: [PATCH v0 linux master] i2c/busses: Avoid i2c interrupt status clear race condition.

2020-04-29 Thread Wolfram Sang
> And is there maybe a Fixes: tag for it? > [Ryan Chen] Yes it is a fix patch. I meant this (from submitting-patches.rst): === If your patch fixes a bug in a specific commit, e.g. you found an issue using ``git bisect``, please use the 'Fixes:' tag with the first 12 characters of the SHA-1 ID,

RE: [PATCH v0 linux master] i2c/busses: Avoid i2c interrupt status clear race condition.

2020-04-29 Thread Ryan Chen
...@lists.infradead.org; linux-asp...@lists.ozlabs.org; linux-kernel@vger.kernel.org Subject: Re: [PATCH v0 linux master] i2c/busses: Avoid i2c interrupt status clear race condition. On Wed, Apr 29, 2020 at 11:37:37AM +0800, ryan_chen wrote: > In AST2600 there have a slow peripheral bus between CPU and

Re: [PATCH v0 linux master] i2c/busses: Avoid i2c interrupt status clear race condition.

2020-04-29 Thread Wolfram Sang
On Wed, Apr 29, 2020 at 11:37:37AM +0800, ryan_chen wrote: > In AST2600 there have a slow peripheral bus between CPU > and i2c controller. > Therefore GIC i2c interrupt status clear have delay timing, > when CPU issue write clear i2c controller interrupt status. > To avoid this issue, the driver

[PATCH v0 linux master] i2c/busses: Avoid i2c interrupt status clear race condition.

2020-04-28 Thread ryan_chen
In AST2600 there have a slow peripheral bus between CPU and i2c controller. Therefore GIC i2c interrupt status clear have delay timing, when CPU issue write clear i2c controller interrupt status. To avoid this issue, the driver need have read after write clear at i2c ISR. Signed-off-by: