linux-kernel - Re: [PATCH V2 3/3] gpio: tegra: Add support for gpio debounce

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <57165EAA.7080304@wwwdotorg.org>
Date:	Tue, 19 Apr 2016 10:36:58 -0600
From:	Stephen Warren <swarren@...dotorg.org>
To:	Laxman Dewangan <ldewangan@...dia.com>
Cc:	linus.walleij@...aro.org, gnurou@...il.com,
	thierry.reding@...il.com, linux-gpio@...r.kernel.org,
	linux-tegra@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH V2 3/3] gpio: tegra: Add support for gpio debounce

On 04/19/2016 10:19 AM, Laxman Dewangan wrote:
>
> On Tuesday 19 April 2016 09:41 PM, Stephen Warren wrote:
>> On 04/19/2016 03:43 AM, Laxman Dewangan wrote:
>>> NVIDIA's Tegra210 support the HW debounce in the GPIO
>>> controller for all its GPIO pins.
>>>
>>> Add support for setting debounce timing by implementing the
>>> set_debounce callback of gpiochip.
>>
>>> diff --git a/drivers/gpio/gpio-tegra.c b/drivers/gpio/gpio-tegra.c
>>
>>> @@ -327,6 +360,9 @@ static int tegra_gpio_resume(struct device *dev)
>>>               tegra_gpio_writel(bank->oe[p], GPIO_OE(gpio));
>>>               tegra_gpio_writel(bank->int_lvl[p], GPIO_INT_LVL(gpio));
>>>               tegra_gpio_writel(bank->int_enb[p], GPIO_INT_ENB(gpio));
>>> +            tegra_gpio_writel(bank->dbc_cnt[p], GPIO_DBC_CNT(gpio));
>>> +            tegra_gpio_writel(bank->dbc_enb[p],
>>> +                      GPIO_MSK_DBC_EN(gpio));
>>
>> Why not just write to the "regular" register rather than the mask
>> register here...
>
> There is no regular register for enabling debounce. Only masked register
> exist.

Sigh. Ignore that comment then:-)