]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/commit
ACPI / SBS: Fix GPE storm on recent MacBookPro's
authorRonald Tschalär <ronald@innovation.ch>
Mon, 1 Oct 2018 02:52:51 +0000 (19:52 -0700)
committerKleber Sacilotto de Souza <kleber.souza@canonical.com>
Wed, 14 Aug 2019 09:18:49 +0000 (11:18 +0200)
commit1808d9cc88fbb9c047ba595ed1ecbbcb32af3ef5
tree75573eb68612280871c6152ed89c61f8d291fa20
parent336b8566bb3449287707bfd0b6837ddae8c53227
ACPI / SBS: Fix GPE storm on recent MacBookPro's

BugLink: https://bugs.launchpad.net/bugs/1838349
[ Upstream commit ca1721c5bee77105829cbd7baab8ee0eab85b06d ]

On Apple machines, plugging-in or unplugging the power triggers a GPE
for the EC. Since these machines expose an SBS device, this GPE ends
up triggering the acpi_sbs_callback(). This in turn tries to get the
status of the SBS charger. However, on MBP13,* and MBP14,* machines,
performing the smbus-read operation to get the charger's status triggers
the EC's GPE again. The result is an endless re-triggering and handling
of that GPE, consuming significant CPU resources (> 50% in irq).

In the end this is quite similar to commit 3031cddea633 (ACPI / SBS:
Don't assume the existence of an SBS charger), except that on the above
machines a status of all 1's is returned. And like there, we just want
ignore the charger here.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=198169
Signed-off-by: Ronald Tschalär <ronald@innovation.ch>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
drivers/acpi/sbs.c