All of lore.kernel.org
 help / color / mirror / Atom feed
From: Philip Munts <phil@munts.net>
To: linux-pwm@vger.kernel.org
Subject: No hotplug event for PCA9685 PWM output device
Date: Wed, 12 Apr 2017 14:09:35 +0200	[thread overview]
Message-ID: <6ecbfb82-ea0f-f403-7655-bb185ba286d3@munts.net> (raw)

I am using a PCA9685 I2C PWM controller on a Raspberry Pi 2.  When I instantiate the PCA9685 device with "echo pca9685 0x40 >new_device" in the I2C bus device directory, I get a hotplug event for pwmchip0, as expected.  When I manually initiate a hotplug event with "echo add >uevent" from the pwmchip0 device directory, I get another hotplug event for pwmchip0, also as expected.

However, when I create a PWM output device with "echo 0 >export" from the pwmchip0 device directory, the PWM output device subdirectory pwm0 is created, including the uevent file, but no hotplug event is generated for pwm0.

Furthermore, when I attempt to manually initiate a hotplug event for pwm0 by running "echo add >uevent" from the pwm0 subdirectory, no hotplug event is generated.

I am using a custom 4.9.21 kernel.  I have reported this at bugzilla.kernel.org: #195335.

Philip Munts
phil@munts.net

                 reply	other threads:[~2017-04-12 12:10 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

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=6ecbfb82-ea0f-f403-7655-bb185ba286d3@munts.net \
    --to=phil@munts.net \
    --cc=linux-pwm@vger.kernel.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.