All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Petr Štetiar" <ynezz@true.cz>
To: Andrew Lunn <andrew@lunn.ch>
Cc: netdev@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Nicolas Ferre <nicolas.ferre@microchip.com>,
	"David S. Miller" <davem@davemloft.net>,
	Florian Fainelli <f.fainelli@gmail.com>,
	Heiner Kallweit <hkallweit1@gmail.com>,
	Rob Herring <robh+dt@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
	Maxime Ripard <maxime.ripard@bootlin.com>,
	Alban Bedel <albeu@free.fr>
Subject: Re: [PATCH v2 3/4] net: macb: Drop nvmem_get_mac_address usage
Date: Mon, 29 Apr 2019 09:55:14 +0200	[thread overview]
Message-ID: <20190429075514.GB346@meh.true.cz> (raw)
In-Reply-To: <20190428213640.GB10772@lunn.ch>

Andrew Lunn <andrew@lunn.ch> [2019-04-28 23:36:40]:

Hi Andrew,

> > so if I understand this correctly, it probably means, that this approach with
> > modified of_get_mac_address is dead end as current of_get_mac_address users
> > don't expect and handle possible -EPROBE_DEFER error, so I would need to
> > change all the current users, which is nonsense.
> 
> I would not say it is dead, it just needs a bit more work.

ok, that's good news, I've probably just misunderstood your concern about the
random MAC address in case when platform/nvmem subsystem returns -EPROBE_DEFER.

> The current users should always be checking for a NULL pointer.  You
> just need to change that to !IS_ERR(). You can then return
> ERR_PTR(-PROBE_DEFER) from the NVMEM operation.

I'm more then happy to address this in v3, but I'm still curious, what is it
going to change in the current state of the tree. 

My understanding of -PROBE_DEFER is, that it needs to be propagated back from
the driver's probe callback/hook to the upper device/driver subsystem in order
to be moved to the list of pending drivers and considered for probe later
again. This is not going to happen in any of the current drivers, thus it will
probably still always result in random MAC address in case of -EPROBE_DEFER
error from the nvmem subsystem.

-- ynezz

  reply	other threads:[~2019-04-29  7:55 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-28 12:53 [PATCH v2 0/4] of_net: Add NVMEM support to of_get_mac_address Petr Štetiar
2019-04-28 12:53 ` Petr Štetiar
2019-04-28 12:53 ` [PATCH v2 1/4] " Petr Štetiar
2019-05-01 20:19   ` Rob Herring
2019-05-02  9:05     ` Petr Štetiar
2019-05-07 16:06       ` Rob Herring
2019-05-08  9:02         ` Petr Štetiar
2019-04-28 12:53 ` [PATCH v2 2/4] dt-bindings: doc: Reflect new NVMEM of_get_mac_address behaviour Petr Štetiar
2019-04-28 12:53   ` Petr Štetiar
2019-04-28 16:53   ` Andrew Lunn
2019-04-28 16:53     ` Andrew Lunn
2019-04-28 16:53     ` Andrew Lunn
2019-05-01 20:22     ` Rob Herring
2019-05-01 20:22       ` Rob Herring
2019-05-01 20:22       ` Rob Herring
2019-04-28 12:53 ` [PATCH v2 3/4] net: macb: Drop nvmem_get_mac_address usage Petr Štetiar
2019-04-28 16:56   ` Andrew Lunn
2019-04-28 21:08     ` Petr Štetiar
2019-04-28 21:36       ` Andrew Lunn
2019-04-29  7:55         ` Petr Štetiar [this message]
2019-04-29 13:02           ` Andrew Lunn
2019-04-30 14:13             ` Handling of EPROBE_DEFER in of_get_mac_address [Was: Re: [PATCH v2 3/4] net: macb: Drop nvmem_get_mac_address usage] Petr Štetiar
2019-05-01 13:54               ` Andrew Lunn
2019-04-28 12:53 ` [PATCH v2 4/4] net: davinci_emac: Drop nvmem_get_mac_address usage Petr Štetiar
2019-04-28 16:58   ` Andrew Lunn

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=20190429075514.GB346@meh.true.cz \
    --to=ynezz@true.cz \
    --cc=albeu@free.fr \
    --cc=andrew@lunn.ch \
    --cc=davem@davemloft.net \
    --cc=devicetree@vger.kernel.org \
    --cc=f.fainelli@gmail.com \
    --cc=frowand.list@gmail.com \
    --cc=hkallweit1@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=maxime.ripard@bootlin.com \
    --cc=netdev@vger.kernel.org \
    --cc=nicolas.ferre@microchip.com \
    --cc=robh+dt@kernel.org \
    --cc=srinivas.kandagatla@linaro.org \
    /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.