lkml.org 
[lkml]   [2019]   [Aug]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v1 41/63] Input: touchscreen: Atmel: Enable IRQ_DISABLE_UNLAZY flag for interrupt
From
Date
Hi Dmitry

On 2019/08/17 2:26, Dmitry Torokhov wrote:
> On Fri, Aug 16, 2019 at 05:35:36PM +0900, Jiada Wang wrote:
>> From: Bhuvanesh Surachari <bhuvanesh_surachari@mentor.com>
>>
>> The de-/serializer driver has defined only irq_mask "ds90ub927_irq_mask" and
>> irq_unmask "ds90ub927_irq_unmask" callback functions. And de-/serializer
>> driver doesn't implement the irq_disable and irq_enable callback functions.
>> Hence inorder to invoke irq_mask callback function when disable_irq_nosync is
>> called the IRQ_DISABLE_UNLAZY interrupt flag should be set. If not the
>> disable_irq_nosync will just increment the depth field in the irq
>> descriptor only once as shown below.
>>
>> disable_irq_nosync
>> __disable_irq_nosync
>> __disable_irq (desc->depth++)
>> irq_disable
>> if irq_disable present -----------> if IRQ_DISABLE_UNLAZYflag set
>> | no |
>> yes | yes |
>> | |
>> desc->irq_data.chip->irq_disable desc->irq_data.chip->irq_unmask
>> (ds90ub927_irq_mask)
>> disable_irq
>> __disable_irq_nosync
>> __disable_irq
>> (desc->depth++)
>> But the enable_irq will try to decrement the depth field twice which generates
>> the backtrace stating "Unbalanced enable for irq 293". This is because there is
>> no IRQ_DISABLE_UNLAZY flag check while calling irq_unmask callback function
>> of the "ds90ub927_irq_unmask" de-/serializer via enable_irq.
>>
>> enable_irq
>> __enable_irq (desc->depth--)
>> irq_enable
>> if irq_enable present -------------> desc->irq_data.chip->irq_unmask
>> | no (ds90ub927_irq_unmask)
>> yes | enable_irq
>> | __enable_irq (desc->depth--)
>> (desc->irq_data.chip->irq_enable)
>
> I'd prefer if we instead did not use the disable_irq_nosync() in the
> driver.
>
sorry for the mistake, during forward port,
I have already eliminated disable_irq_nosync(),
so this patch is no longer needed,
will drop it in v2 patch-set

Thanks,
Jiada

> Thanks.
>

\
 
 \ /
  Last update: 2019-08-22 08:26    [W:0.085 / U:0.032 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site