linux-kernel - Re: [PATCH v1 1/1] gpio: gpio-crystalcove: Skip IRQ CTRL register update for virtual GPIOs

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Date:   Tue, 11 Jul 2017 10:20:50 -0700
From:   "Kuppuswamy, Sathyanarayanan" <sathyaosid@...il.com>
To:     Hans de Goede <hdegoede@...hat.com>,
        sathyanarayanan.kuppuswamy@...ux.intel.com,
        Andy Shevchenko <andy.shevchenko@...il.com>
Cc:     Linus Walleij <linus.walleij@...aro.org>,
        "linux-gpio@...r.kernel.org" <linux-gpio@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v1 1/1] gpio: gpio-crystalcove: Skip IRQ CTRL register
 update for virtual GPIOs

Hi Hans,


On 7/11/2017 2:47 AM, Hans de Goede wrote:
> Hi,
>
> On 11-07-17 01:35, sathyanarayanan kuppuswamy wrote:
>> Hi Hans,
>>
>> Do you have any comments on this patch ? It kind of fixes your patch, 
>> so would prefer to get your comments.
>
> Sorry I did not notice this patch before, did you Cc me ?
>
> As for the patch, I deliberately did not add the check
> to crystalcove_update_irq_ctrl, crystalcove_update_irq_ctrl
> only gets called from crystalcove_bus_sync_unlock if
> UPDATE_IRQ_TYPE
>
> UPDATE_IRQ_TYPE only gets set from crystalcove_irq_type
> which at the top contains:
>
>         if (data->hwirq >= CRYSTALCOVE_GPIO_NUM)
>                 return 0;
>
> So crystalcove_update_irq_ctrl will never get called for
> virtual GPIOs.
>
> TL;DR: your patch is not necessary.
Thanks for the clarification.
>
> Regards,
>
> Hans
>
>
>>
>>
>> On 06/15/2017 02:45 PM, sathyanarayanan kuppuswamy wrote:
>>> Hi Andy,
>>>
>>>
>>> On 06/15/2017 02:19 AM, Andy Shevchenko wrote:
>>>> On Thu, Jun 15, 2017 at 2:21 AM,
>>>> <sathyanarayanan.kuppuswamy@...ux.intel.com> wrote:
>>>>> From: Kuppuswamy Sathyanarayanan 
>>>>> <sathyanarayanan.kuppuswamy@...ux.intel.com>
>>>>>
>>>>> Commit 9a752b4c9ab9 ("gpio: crystalcove: Do not write regular gpio
>>>>> registers for virtual GPIOs") added support to skip GPIO register
>>>>> update for virtual GPIOs, but it missed to add skip logic in
>>>>> crystalcove_update_irq_ctrl() function. This patch fixes it.
>>>>> @@ -134,6 +134,9 @@ static void crystalcove_update_irq_ctrl(struct 
>>>>> crystalcove_gpio *cg, int gpio)
>>>>>   {
>>>>>          int reg = to_reg(gpio, CTRL_IN);
>>>>>
>>>>> +       if (reg < 0)
>>>>> +               return;
>>>>> +
>>>>>          regmap_update_bits(cg->regmap, reg, CTLI_INTCNT_BE, 
>>>>> cg->intcnt_value);
>>>>>   }
>>>> Shouldn't it have been done using irq_valid_mask flag in the first 
>>>> place?
>>> Agree. Setting irq_valid_mask would be the proper approach to skip 
>>> IRQ for some GPIO pins. But commit 9a752b4c9ab9 added the GPIO index 
>>> based checks in other IRQ set/unset functions in this driver and 
>>> missed to add it only in this update_irq_ctrl() function. May be I 
>>> can submit a separate patch to clean it up and use logic based on 
>>> setting irq_valid_mask.
>>>
>>> Even if we do the cleanup patch, I would still prefer to have this 
>>> check. Since to_reg() can return value < 0, its good to check it 
>>> before passing it to regmap_* functions. Let me know your comments.
>>>
>>>>
>>>
>>