Linux Input Archive on lore.kernel.org
 help / color / Atom feed
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
To: Robin Gong <yibin.gong@nxp.com>
Cc: robin <robin@protonic.nl>,
	"linux-input @ vger . kernel . org" <linux-input@vger.kernel.org>,
	"linux-kernel @ vger . kernel . org"
	<linux-kernel@vger.kernel.org>,
	Pengutronix Kernel Team <kernel@pengutronix.de>,
	Marco Felsch <m.felsch@pengutronix.de>,
	Shawn Guo <shawnguo@kernel.org>, Adam Ford <aford173@gmail.com>,
	"linux-arm-kernel @ lists . infradead . org"
	<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v3] input: keyboard: snvs_pwrkey: Send key events for i.MX6 S, DL and Q
Date: Mon, 16 Sep 2019 16:37:01 -0700
Message-ID: <20190916233701.GH237523@dtor-ws> (raw)
In-Reply-To: <VE1PR04MB663896B94C68B5EF9AE0BE36898C0@VE1PR04MB6638.eurprd04.prod.outlook.com>

On Mon, Sep 16, 2019 at 07:45:37AM +0000, Robin Gong wrote:
> On 2019/9/13 15:31 robin <robin@protonic.nl> wrote:> 
> > Hi Dmitry,
> > 
> > On 2019-09-12 22:13, Dmitry Torokhov wrote:
> > > Hi Robin,
> > >
> > > On Wed, Sep 04, 2019 at 06:23:29AM +0000, Robin van der Gracht wrote:
> > >> The first generation i.MX6 processors does not send an interrupt when
> > >> the power key is pressed. It sends a power down request interrupt if
> > >> the key is released before a hard shutdown (5 second press). This
> > >> should allow software to bring down the SoC safely.
> > >>
> > >> For this driver to work as a regular power key with the older SoCs,
> > >> we need to send a keypress AND release when we get the power down
> > >> request irq.
> > >>
> > >> Signed-off-by: Robin van der Gracht <robin@protonic.nl>
> > >> ---
> > >> @@ -67,13 +83,17 @@ static irqreturn_t imx_snvs_pwrkey_interrupt(int
> > >> irq, void *dev_id)  {
> > >>  	struct platform_device *pdev = dev_id;
> > >>  	struct pwrkey_drv_data *pdata = platform_get_drvdata(pdev);
> > >> +	unsigned long expire = jiffies;
> > >>  	u32 lp_status;
> > >>
> > >>  	pm_wakeup_event(pdata->input->dev.parent, 0);
> > >>
> > >>  	regmap_read(pdata->snvs, SNVS_LPSR_REG, &lp_status);
> > >> -	if (lp_status & SNVS_LPSR_SPO)
> > >> -		mod_timer(&pdata->check_timer, jiffies +
> > >> msecs_to_jiffies(DEBOUNCE_TIME));
> > >> +	if (lp_status & SNVS_LPSR_SPO) {
> > >> +		if (pdata->minor_rev > 0)
> > >> +			expire = jiffies + msecs_to_jiffies(DEBOUNCE_TIME);
> > >> +		mod_timer(&pdata->check_timer, expire);
> > >
> > > Why do we even need to fire the timer in case of the first generation
> > > hardware? Just send press and release events directly from the ISR.
> That timer looks like a software debounce to prevent unexpected and
> meaningless interrupt/event caused by quick press/release.   

Right, but in case of the first generation hardware we schedule the
timer immediately (expire == 0) and do not check state of the hardware
in the timer handler, but rather simply emit down/up events, so we do
not really get any benefit from the timer (again, I am talking about
first generation hardware only).

Thanks.

-- 
Dmitry

  reply index

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-04  6:23 Robin van der Gracht
2019-09-04  6:52 ` Marco Felsch
2019-09-13  7:39   ` robin
2019-09-12 20:13 ` Dmitry Torokhov
2019-09-13  7:30   ` robin
2019-09-16  7:45     ` Robin Gong
2019-09-16 23:37       ` Dmitry Torokhov [this message]
2019-11-20  9:27         ` Marco Felsch
2019-11-20 16:32           ` robin
2019-11-21 13:17             ` Robin Gong
2019-11-22 22:48               ` Dmitry Torokhov

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190916233701.GH237523@dtor-ws \
    --to=dmitry.torokhov@gmail.com \
    --cc=aford173@gmail.com \
    --cc=kernel@pengutronix.de \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-input@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=m.felsch@pengutronix.de \
    --cc=robin@protonic.nl \
    --cc=shawnguo@kernel.org \
    --cc=yibin.gong@nxp.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux Input Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-input/0 linux-input/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-input linux-input/ https://lore.kernel.org/linux-input \
		linux-input@vger.kernel.org
	public-inbox-index linux-input

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-input


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git