We already set DPM_FLAG_SMART_PREPARE, so we completely skip all
callbacks (other then prepare) where possible, quoting from
dw_i2c_plat_prepare():
/*
* If the ACPI companion device object is present for this device, it
* may be accessed during suspend and resume of other devices via I2C
* operation regions, so tell the PM core and middle layers to avoid
* skipping system suspend/resume callbacks for it in that case.
*/
return !has_acpi_companion(dev);
Also setting the DPM_FLAG_SMART_SUSPEND will cause acpi_subsys_suspend()
to leave the controller runtime-suspended even if dw_i2c_plat_prepare()
returned 0.
Leaving the controller runtime-suspended normally, when the I2C controller
is suspended during the suspend_late phase, is not an issue because
the pm_runtime_get_sync() done by i2c_dw_xfer() will (runtime-)resume it.
But for dw I2C controllers on Bay- and Cherry-Trail devices acpi_lpss.c
leaves the controller alive until the suspend_noirq phase, because it may
be used by the _PS3 ACPI methods of PCI devices and PCI devices are left
powered on until the suspend_noirq phase.
Between the suspend_late and resume_early phases runtime-pm is disabled.
So for any ACPI I2C OPRegion accesses done after the suspend_late phase,
the pm_runtime_get_sync() done by i2c_dw_xfer() is a no-op and the
controller is left runtime-suspended.
i2c_dw_xfer() has a check to catch this condition (rather then waiting
for the I2C transfer to timeout because the controller is suspended).
acpi_subsys_suspend() leaving the controller runtime-suspended in
combination with an ACPI I2C OPRegion access done after the suspend_late
phase triggers this check, leading to the following error being logged
on a Bay Trail based Lenovo Thinkpad 8 tablet:
[ 93.275882] i2c_designware 80860F41:00: Transfer while suspended
[ 93.275993] WARNING: CPU: 0 PID: 412 at drivers/i2c/busses/i2c-designware-master.c:429 i2c_dw_xfer+0x239/0x280
...
[ 93.276252] Workqueue: kacpi_notify acpi_os_execute_deferred
[ 93.276267] RIP: 0010:i2c_dw_xfer+0x239/0x280
...
[ 93.276340] Call Trace:
[ 93.276366] __i2c_transfer+0x121/0x520
[ 93.276379] i2c_transfer+0x4c/0x100
[ 93.276392] i2c_acpi_space_handler+0x219/0x510
[ 93.276408] ? up+0x40/0x60
[ 93.276419] ? i2c_acpi_notify+0x130/0x130
[ 93.276433] acpi_ev_address_space_dispatch+0x1e1/0x252
...
So since on BYT and CHT platforms we want ACPI I2c OPRegion accesses
to work until the suspend_noirq phase, we need the controller to be
runtime-resumed during the suspend phase if it is runtime-suspended
suspended at that time. This means that we must not set the
DPM_FLAG_SMART_SUSPEND on these platforms.
On BYT and CHT we already have a special ACCESS_NO_IRQ_SUSPEND flag
to make sure the controller stays functional until the suspend_noirq
phase. This commit makes the driver not set the DPM_FLAG_SMART_SUSPEND
flag when that flag is set.
Cc: stable(a)vger.kernel.org
Fixes: b30f2f65568f ("i2c: designware: Set IRQF_NO_SUSPEND flag for all BYT and CHT controllers")
Signed-off-by: Hans de Goede <hdegoede(a)redhat.com>
---
drivers/i2c/busses/i2c-designware-platdrv.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 3b7d58c2fe85..15b4b965b443 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -371,10 +371,16 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
adap->dev.of_node = pdev->dev.of_node;
adap->nr = -1;
- dev_pm_set_driver_flags(&pdev->dev,
- DPM_FLAG_SMART_PREPARE |
- DPM_FLAG_SMART_SUSPEND |
- DPM_FLAG_LEAVE_SUSPENDED);
+ if (dev->flags & ACCESS_NO_IRQ_SUSPEND) {
+ dev_pm_set_driver_flags(&pdev->dev,
+ DPM_FLAG_SMART_PREPARE |
+ DPM_FLAG_LEAVE_SUSPENDED);
+ } else {
+ dev_pm_set_driver_flags(&pdev->dev,
+ DPM_FLAG_SMART_PREPARE |
+ DPM_FLAG_SMART_SUSPEND |
+ DPM_FLAG_LEAVE_SUSPENDED);
+ }
/* The code below assumes runtime PM to be disabled. */
WARN_ON(pm_runtime_enabled(&pdev->dev));
--
2.26.0
Please queue up the following networking bug fixes for v5.5 and v5.6
-stable, respectively.
Also, there is a Realtek PHY patch attached which should be queued up
for v5.4.
Thank you.
From: Ross Lagerwall <ross.lagerwall(a)citrix.com>
commit 45c8184c1bed1ca8a7f02918552063a00b909bf5 upstream.
Update the features after calling register_netdev() otherwise the
device features are not set up correctly and it not possible to change
the MTU of the device. After this change, the features reported by
ethtool match the device's features before the commit which introduced
the issue and it is possible to change the device's MTU.
Fixes: f599c64fdf7d ("xen-netfront: Fix race between device setup and open")
Reported-by: Liam Shepherd <liam(a)dancer.es>
Signed-off-by: Ross Lagerwall <ross.lagerwall(a)citrix.com>
Reviewed-by: Juergen Gross <jgross(a)suse.com>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
Signed-off-by: Nobuhiro Iwamatsu (CIP) <nobuhiro1.iwamatsu(a)toshiba.co.jp>
---
drivers/net/xen-netfront.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index 744b111cff6a3..e99a07d5fda71 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -1982,10 +1982,6 @@ static int xennet_connect(struct net_device *dev)
/* talk_to_netback() sets the correct number of queues */
num_queues = dev->real_num_tx_queues;
- rtnl_lock();
- netdev_update_features(dev);
- rtnl_unlock();
-
if (dev->reg_state == NETREG_UNINITIALIZED) {
err = register_netdev(dev);
if (err) {
@@ -1995,6 +1991,10 @@ static int xennet_connect(struct net_device *dev)
}
}
+ rtnl_lock();
+ netdev_update_features(dev);
+ rtnl_unlock();
+
/*
* All public and private state should now be sane. Get
* ready to start sending and receiving packets and give the driver
--
2.26.0