All of lore.kernel.org
 help / color / mirror / Atom feed
From: Felipe Balbi <balbi@ti.com>
To: Pavel Machek <pavel@ucw.cz>
Cc: Baolin Wang <baolin.wang@linaro.org>,
	Greg KH <gregkh@linuxfoundation.org>,
	sre@kernel.org, dbaryshkov@gmail.com, dwmw2@infradead.org,
	peter.chen@freescale.com, stern@rowland.harvard.edu,
	r.baldyga@samsung.com, sojka@merica.cz,
	yoshihiro.shimoda.uh@renesas.com, linux-usb@vger.kernel.org,
	linux-kernel@vger.kernel.org, sameo@linux.intel.com,
	lee.jones@linaro.org, ckeepax@opensource.wolfsonmicro.com,
	broonie@kernel.org, patches@opensource.wolfsonmicro.com,
	linux-pm@vger.kernel.org,
	device-mainlining@lists.linuxfoundation.org
Subject: Re: [PATCH v4 1/5] gadget: Introduce the notifier functions
Date: Fri, 9 Oct 2015 16:17:27 -0500	[thread overview]
Message-ID: <87oag7u4go.fsf@saruman.tx.rr.com> (raw)
In-Reply-To: <20151008155052.GH11776@xo-6d-61-c0.localdomain>

[-- Attachment #1: Type: text/plain, Size: 1544 bytes --]


Hi,

Pavel Machek <pavel@ucw.cz> writes:
> HI!
>
>> > +	int ret;
>> > +
>> > +	mutex_lock(&gadget->lock);
>> > +	ret = raw_notifier_chain_unregister(&gadget->nh, nb);
>> 
>> Greg, this is the kind of thing I wanted to avoid adding more of.
>> 
>> I was wondering if you would accept subsystems using kdbus for
>> this sort of notification. I'm okay waiting for kdbus for another
>> couple merge windows (if we have to) before that's merged, but
>> if we take this raw notifier approach now, we will end up having
>> to support it forever.
>> 
>> Also, because soon enough we will have to support USB Power Delivery
>> with Type C connector, this is bound to change in the coming months.
>> 
>> Frankly, I wanted all of this to be decided in userland with the
>> kernel just providing notification and basic safety checks (we don't
>> want to allow a bogus userspace daemon frying anybody's devices).
>> 
>> How would you feel about that ?
>
> So init=/bin/bash boot no longer provides machine that charges itself?
>
> That would be bad. Traditionally, hardware controls battery charging,
> and if hardware needs some help, we should do it in kernel, to mask
> the difference from userspace.

this is a very valid point which I hadn't considered :-)

Seems like kernel it is, no matter how easy or how difficult it gets.

Mark, when can we try to have a discussion about how to get this
upstream ? It seems like designing everything in the mailing list will
just take forever. Any ideas ?

-- 
balbi

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 818 bytes --]

WARNING: multiple messages have this Message-ID (diff)
From: Felipe Balbi <balbi@ti.com>
To: Pavel Machek <pavel@ucw.cz>
Cc: Baolin Wang <baolin.wang@linaro.org>,
	Greg KH <gregkh@linuxfoundation.org>, <sre@kernel.org>,
	<dbaryshkov@gmail.com>, <dwmw2@infradead.org>,
	<peter.chen@freescale.com>, <stern@rowland.harvard.edu>,
	<r.baldyga@samsung.com>, <sojka@merica.cz>,
	<yoshihiro.shimoda.uh@renesas.com>, <linux-usb@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>, <sameo@linux.intel.com>,
	<lee.jones@linaro.org>, <ckeepax@opensource.wolfsonmicro.com>,
	<broonie@kernel.org>, <patches@opensource.wolfsonmicro.com>,
	<linux-pm@vger.kernel.org>,
	<device-mainlining@lists.linuxfoundation.org>
Subject: Re: [PATCH v4 1/5] gadget: Introduce the notifier functions
Date: Fri, 9 Oct 2015 16:17:27 -0500	[thread overview]
Message-ID: <87oag7u4go.fsf@saruman.tx.rr.com> (raw)
In-Reply-To: <20151008155052.GH11776@xo-6d-61-c0.localdomain>

[-- Attachment #1: Type: text/plain, Size: 1544 bytes --]


Hi,

Pavel Machek <pavel@ucw.cz> writes:
> HI!
>
>> > +	int ret;
>> > +
>> > +	mutex_lock(&gadget->lock);
>> > +	ret = raw_notifier_chain_unregister(&gadget->nh, nb);
>> 
>> Greg, this is the kind of thing I wanted to avoid adding more of.
>> 
>> I was wondering if you would accept subsystems using kdbus for
>> this sort of notification. I'm okay waiting for kdbus for another
>> couple merge windows (if we have to) before that's merged, but
>> if we take this raw notifier approach now, we will end up having
>> to support it forever.
>> 
>> Also, because soon enough we will have to support USB Power Delivery
>> with Type C connector, this is bound to change in the coming months.
>> 
>> Frankly, I wanted all of this to be decided in userland with the
>> kernel just providing notification and basic safety checks (we don't
>> want to allow a bogus userspace daemon frying anybody's devices).
>> 
>> How would you feel about that ?
>
> So init=/bin/bash boot no longer provides machine that charges itself?
>
> That would be bad. Traditionally, hardware controls battery charging,
> and if hardware needs some help, we should do it in kernel, to mask
> the difference from userspace.

this is a very valid point which I hadn't considered :-)

Seems like kernel it is, no matter how easy or how difficult it gets.

Mark, when can we try to have a discussion about how to get this
upstream ? It seems like designing everything in the mailing list will
just take forever. Any ideas ?

-- 
balbi

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 818 bytes --]

  reply	other threads:[~2015-10-09 21:18 UTC|newest]

Thread overview: 38+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-09-24 17:39 [PATCH v4 0/5] Introduce usb charger framework to deal with the usb gadget power negotation Baolin Wang
2015-09-24 17:39 ` [PATCH v4 1/5] gadget: Introduce the notifier functions Baolin Wang
2015-10-01 17:29   ` Felipe Balbi
2015-10-01 17:29     ` Felipe Balbi
2015-10-01 17:43     ` Mark Brown
2015-10-01 17:58       ` Felipe Balbi
2015-10-01 17:58         ` Felipe Balbi
2015-10-01 18:01         ` Felipe Balbi
2015-10-01 18:01           ` Felipe Balbi
2015-10-02 16:47         ` Mark Brown
2015-10-02 17:23           ` Felipe Balbi
2015-10-02 17:23             ` Felipe Balbi
2015-10-02 18:49             ` Mark Brown
     [not found]               ` <20151002184909.GC12635-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2015-10-02 19:11                 ` Felipe Balbi
2015-10-02 19:11                   ` Felipe Balbi
2015-10-04 22:55                   ` Mark Brown
2015-10-05 15:15                     ` Felipe Balbi
2015-10-05 15:15                       ` Felipe Balbi
2015-10-05 16:18                       ` Mark Brown
     [not found]                         ` <20151005161833.GZ12635-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2015-10-05 16:29                           ` Felipe Balbi
2015-10-05 16:29                             ` Felipe Balbi
2015-10-07 16:44             ` [Device-mainlining] " Bjorn Andersson
2015-10-08 15:51         ` Pavel Machek
2015-10-02  5:41     ` Greg KH
2015-10-02 17:27       ` Felipe Balbi
2015-10-02 17:27         ` Felipe Balbi
2015-10-08 15:50     ` Pavel Machek
2015-10-09 21:17       ` Felipe Balbi [this message]
2015-10-09 21:17         ` Felipe Balbi
2015-10-12 16:56         ` Mark Brown
     [not found]         ` <87oag7u4go.fsf-HgARHv6XitJaoMGHk7MhZQC/G2K4zDHf@public.gmane.org>
2016-04-09 16:01           ` Pavel Machek
2016-04-09 16:01             ` Pavel Machek
2015-09-24 17:39 ` [PATCH v4 2/5] gadget: Introduce the usb charger framework Baolin Wang
2015-09-24 17:39 ` [PATCH v4 3/5] gadget: Support for " Baolin Wang
2015-09-24 17:39 ` [PATCH v4 4/5] gadget: Integrate with the usb gadget supporting for usb charger Baolin Wang
2015-09-24 17:39 ` [PATCH v4 5/5] power: wm831x_power: Support USB charger current limit management Baolin Wang
  -- strict thread matches above, loose matches on Subject: below --
2015-08-19  9:13 [PATCH v4 0/5] Introduce usb charger framework to deal with the usb gadget power negotation Baolin Wang
     [not found] ` <cover.1439974219.git.baolin.wang-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
2015-08-19  9:13   ` [PATCH v4 1/5] gadget: Introduce the notifier functions Baolin Wang
2015-08-19  9:13     ` Baolin Wang

Reply instructions:

You may reply publicly 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=87oag7u4go.fsf@saruman.tx.rr.com \
    --to=balbi@ti.com \
    --cc=baolin.wang@linaro.org \
    --cc=broonie@kernel.org \
    --cc=ckeepax@opensource.wolfsonmicro.com \
    --cc=dbaryshkov@gmail.com \
    --cc=device-mainlining@lists.linuxfoundation.org \
    --cc=dwmw2@infradead.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=lee.jones@linaro.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --cc=patches@opensource.wolfsonmicro.com \
    --cc=pavel@ucw.cz \
    --cc=peter.chen@freescale.com \
    --cc=r.baldyga@samsung.com \
    --cc=sameo@linux.intel.com \
    --cc=sojka@merica.cz \
    --cc=sre@kernel.org \
    --cc=stern@rowland.harvard.edu \
    --cc=yoshihiro.shimoda.uh@renesas.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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.