All of lore.kernel.org
 help / color / mirror / Atom feed
From: Phil Reid <preid@electromag.com.au>
To: wsa@the-dreams.de, peda@axentia.se, linux-i2c@vger.kernel.org
Cc: Phil Reid <preid@electromag.com.au>
Subject: [RFC PATCH 0/1] i2c: i2c-mux-pca954x: Add interrupt controller support
Date: Wed, 27 Jul 2016 11:05:55 +0800	[thread overview]
Message-ID: <1469588756-70579-1-git-send-email-preid@electromag.com.au> (raw)

G'day All,

I'm seeking some feedback on this. Not really happy with it but can't think
of a good solution.  

This patch adds support to read the irq status register from the a PCA9543
i2c mux. This chip has two active low interrupt inputs with are combined    
into a single active low interrupt output. It does not provide the ability 
to mask interrupts. Only to read which interrupt line is active.

On the hardware I'm interfacing too I have an ltc1760 sbs manager on each 
multiplexed bus. On booting these may assert there SMBALERT irq outputs 
immediately, again these devices have no ability to mask there interrupt. 
So the irq is asserted during boot until the ltc1760 driver is started.
And there's no way to mask it. My work around is to enable the irq until both
irq pins are unmasked. Not sure what else to do. The masking could be a dts
property to make it configurable.

ltc1760 driver is currently being review for submission in 
Karl-Heinz Schneider <karl-heinz@schneider-inet.de> patch series.

Appreciate any feedback on what could be done here.


Phil Reid (1):
  i2c: i2c-mux-pca954x: Add interrupt controller support.

 drivers/i2c/muxes/i2c-mux-pca954x.c | 116 ++++++++++++++++++++++++++++++++++++
 1 file changed, 116 insertions(+)

-- 
1.8.3.1

             reply	other threads:[~2016-07-27  3:14 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-07-27  3:05 Phil Reid [this message]
2016-07-27  3:05 ` [RFC PATCH 1/1] i2c: i2c-mux-pca954x: Add interrupt controller support Phil Reid
2016-07-27  5:32   ` Peter Rosin
2016-07-28  2:44     ` Phil Reid
2016-07-29  5:48       ` Peter Rosin
2016-07-29  5:48         ` Peter Rosin
2016-08-01  6:25         ` Phil Reid
2016-08-01  8:22           ` Peter Rosin
2016-08-01  8:22             ` Peter Rosin
2016-08-01  8:52             ` Phil Reid

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=1469588756-70579-1-git-send-email-preid@electromag.com.au \
    --to=preid@electromag.com.au \
    --cc=linux-i2c@vger.kernel.org \
    --cc=peda@axentia.se \
    --cc=wsa@the-dreams.de \
    /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.