linux-acpi.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Hans de Goede <hdegoede@redhat.com>
To: "Rafael J . Wysocki" <rjw@rjwysocki.net>,
	Len Brown <lenb@kernel.org>, Bjorn Helgaas <bhelgaas@google.com>,
	Robert Moore <robert.moore@intel.com>,
	Lv Zheng <lv.zheng@intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>,
	linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org,
	devel@acpica.org
Subject: ACPI: Do not call _STA on battery devices with unmet dependencies
Date: Thu, 18 Jan 2018 17:03:55 +0100	[thread overview]
Message-ID: <20180118160359.29971-1-hdegoede@redhat.com> (raw)

Hi All,

The ACPI code already contains quite a bit of code to not bind the
ACPI-battery until all deps for an ACPI battery device have been met,
but on some devices calling _STA before all deps are met is a problem
too because the _STA method uses an i2c OpRegion there.

Here is the DSDT of the device I'm seeing this on:
https://fedorapeople.org/~jwrdegoede/toshiba-click-mini-dsdt.dsl

This series modifies the kernel to not call _STA until all deps are met,
mirroring the binding behavior of the battery driver.

Without this series a total of 32 ACPI errors get printend to the console
on boot, there are 4 errors per _STA call, 2 battery devices on this
system and 4 _STA calls per battery device.

The first commit is a preparation commit for making the ACPICA changes
in the 4th commit, this commit is necessary to not break things after
the ACPICA changes.

The second commit modifies acpi_bus_get_status to not call _STA on
battery devices until all deps are met. This fixes 2 of the 4 too early
_STA calls triggering these errors.

The third commit makes the device instantiation code use
acpi_bus_get_status instead of acpi_bus_get_status_handle so that the
code to get the initial status also does not makes 1 too early _STA call.

The fourth commit changes the ACPICA acpi_get_object_info function to not
call _STA. Only 1 user (which is fixed in the first commit) cares about
acpi_device_info.current_status. And the ACPICA code has this comment:

 * Note: This interface is intended to be used during the initial device
 * discovery namespace traversal. Therefore, no complex methods can be
 * executed, especially those that access operation regions. Therefore, do
 * not add any additional methods that could cause problems in this area.
 * Because of this reason support for the following methods has been removed:
 * this was the fate of the _SUB method which was found to cause such
 * problems and was removed (11/2015).

The described problems with the _SUB method clearly also apply to the _STA
method, so removing it from acpi_get_object_info seems like it is the right
thing to do here. This too fixes 1 too early _STA call, so that with all
4 patches in place we've fixed all 4 too early _STA calls.

Regards,

Hans

             reply	other threads:[~2018-01-18 16:04 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-01-18 16:03 Hans de Goede [this message]
2018-01-18 16:03 ` [PATCH 1/4] PCI: acpiphp_ibm: prepare for acpi_get_object_info no longer returning status Hans de Goede
2018-01-18 19:13   ` Bjorn Helgaas
2018-01-19 11:38     ` Hans de Goede
2018-01-18 16:03 ` [PATCH 2/4] ACPI / bus: Do not call _STA on battery devices with unmet dependencies Hans de Goede
2018-01-18 16:03 ` [PATCH 3/4] ACPI / scan: Use acpi_bus_get_status for initial status of ACPI_TYPE_DEVICE devs Hans de Goede
2018-01-18 16:03 ` [PATCH 4/4] ACPICA: Remove calling of _STA from acpi_get_object_info Hans de Goede
2018-01-18 19:11 ` ACPI: Do not call _STA on battery devices with unmet dependencies Bjorn Helgaas
2018-01-19 21:03   ` Schmauss, Erik
2018-01-20 12:48     ` Hans de Goede
2018-01-23  0:24       ` Schmauss, Erik
2018-01-26 15:46         ` Hans de Goede

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=20180118160359.29971-1-hdegoede@redhat.com \
    --to=hdegoede@redhat.com \
    --cc=bhelgaas@google.com \
    --cc=devel@acpica.org \
    --cc=lenb@kernel.org \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=lv.zheng@intel.com \
    --cc=rjw@rjwysocki.net \
    --cc=robert.moore@intel.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).