Hi Oleksij,

On 09.06.2021 14:46, Oleksij Rempel wrote:

On Wed, Jun 09, 2021 at 11:59:23AM +0200, Marek Szyprowski wrote:

quoted

On 07.06.2021 10:27, Oleksij Rempel wrote:

quoted

To be able to use ax88772 with external PHYs and use advantage of
existing PHY drivers, we need to port at least ax88772 part of asix
driver to the phylib framework.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>

This patch landed recently in linux-next as commit e532a096be0e ("net:
usb: asix: ax88772: add phylib support"). I found that it causes some
warnings on boards with those devices, see the following log:

root@target:~# time rtcwake -s10 -mmem
rtcwake: wakeup from "mem" using /dev/rtc0 at Wed Jun  9 08:16:41 2021
[  231.226579] PM: suspend entry (deep)
[  231.231697] Filesystems sync: 0.002 seconds
[  231.261761] Freezing user space processes ... (elapsed 0.002 seconds)
done.
[  231.270526] OOM killer disabled.
[  231.273557] Freezing remaining freezable tasks ... (elapsed 0.002
seconds) done.
[  231.282229] printk: Suspending console(s) (use no_console_suspend to
debug)
...
[  231.710852] Disabling non-boot CPUs ...
...
[  231.901794] Enabling non-boot CPUs ...
...
[  232.225640] usb usb3: root hub lost power or was reset
[  232.225746] usb usb1: root hub lost power or was reset
[  232.225864] usb usb5: root hub lost power or was reset
[  232.226206] usb usb6: root hub lost power or was reset
[  232.226207] usb usb4: root hub lost power or was reset
[  232.297749] usb usb2: root hub lost power or was reset
[  232.343227] asix 3-1:1.0 eth0: Failed to write reg index 0x0000: -22
[  232.343293] asix 3-1:1.0 eth0: Failed to enable software MII access
[  232.344486] asix 3-1:1.0 eth0: Failed to read reg index 0x0000: -22
[  232.344512] asix 3-1:1.0 eth0: Failed to write reg index 0x0000: -22
[  232.344529] PM: dpm_run_callback(): mdio_bus_phy_resume+0x0/0x78
returns -22
[  232.344554] Asix Electronics AX88772C usb-003:002:10: PM: failed to
resume: error -22
[  232.563712] usb 1-1: reset high-speed USB device number 2 using
exynos-ehci
[  232.757653] usb 3-1: reset high-speed USB device number 2 using xhci-hcd
[  233.730994] OOM killer enabled.
[  233.734122] Restarting tasks ... done.
[  233.754992] PM: suspend exit

real    0m11.546s
user    0m0.000s
sys     0m0.530s
root@target:~# sleep 2
root@target:~# time rtcwake -s10 -mmem
rtcwake: wakeup from "mem" using /dev/rtc0 at Wed Jun  9 08:17:02 2021
[  241.959608] PM: suspend entry (deep)
[  241.963446] Filesystems sync: 0.001 seconds
[  241.978619] Freezing user space processes ... (elapsed 0.004 seconds)
done.
[  241.989199] OOM killer disabled.
[  241.992215] Freezing remaining freezable tasks ... (elapsed 0.005
seconds) done.
[  242.003979] printk: Suspending console(s) (use no_console_suspend to
debug)
...
[  242.592030] Disabling non-boot CPUs ...
...
[  242.879721] Enabling non-boot CPUs ...
...
[  243.145870] usb usb3: root hub lost power or was reset
[  243.145910] usb usb4: root hub lost power or was reset
[  243.147084] usb usb5: root hub lost power or was reset
[  243.147157] usb usb6: root hub lost power or was reset
[  243.147298] usb usb1: root hub lost power or was reset
[  243.217137] usb usb2: root hub lost power or was reset
[  243.283807] asix 3-1:1.0 eth0: Failed to write reg index 0x0000: -22
[  243.284005] asix 3-1:1.0 eth0: Failed to enable software MII access
[  243.285526] asix 3-1:1.0 eth0: Failed to read reg index 0x0000: -22
[  243.285676] asix 3-1:1.0 eth0: Failed to read reg index 0x0004: -22
[  243.285769] ------------[ cut here ]------------
[  243.286011] WARNING: CPU: 2 PID: 2069 at drivers/net/phy/phy.c:916
phy_error+0x28/0x68
[  243.286115] Modules linked in: cmac bnep mwifiex_sdio mwifiex
sha256_generic libsha256 sha256_arm cfg80211 btmrvl_sdio btmrvl
bluetooth s5p_mfc uvcvideo s5p_jpeg exynos_gsc v
[  243.287490] CPU: 2 PID: 2069 Comm: kworker/2:5 Not tainted
5.13.0-rc5-next-20210608 #10443
[  243.287555] Hardware name: Samsung Exynos (Flattened Device Tree)
[  243.287609] Workqueue: events_power_efficient phy_state_machine
[  243.287716] [<c0111920>] (unwind_backtrace) from [<c010d0cc>]
(show_stack+0x10/0x14)
[  243.287807] [<c010d0cc>] (show_stack) from [<c0b62360>]
(dump_stack_lvl+0xa0/0xc0)
[  243.287882] [<c0b62360>] (dump_stack_lvl) from [<c0127960>]
(__warn+0x118/0x11c)
[  243.287954] [<c0127960>] (__warn) from [<c0127a18>]
(warn_slowpath_fmt+0xb4/0xbc)
[  243.288021] [<c0127a18>] (warn_slowpath_fmt) from [<c0734968>]
(phy_error+0x28/0x68)
[  243.288094] [<c0734968>] (phy_error) from [<c0735d6c>]
(phy_state_machine+0x218/0x278)
[  243.288173] [<c0735d6c>] (phy_state_machine) from [<c014ae08>]
(process_one_work+0x30c/0x884)
[  243.288254] [<c014ae08>] (process_one_work) from [<c014b3d8>]
(worker_thread+0x58/0x594)
[  243.288333] [<c014b3d8>] (worker_thread) from [<c0153944>]
(kthread+0x160/0x1c0)
[  243.288408] [<c0153944>] (kthread) from [<c010011c>]
(ret_from_fork+0x14/0x38)
[  243.288475] Exception stack(0xc4683fb0 to 0xc4683ff8)
[  243.288531] 3fa0:                                     00000000
00000000 00000000 00000000
[  243.288587] 3fc0: 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000
[  243.288641] 3fe0: 00000000 00000000 00000000 00000000 00000013 00000000
[  243.288690] irq event stamp: 1611
[  243.288744] hardirqs last  enabled at (1619): [<c01a6ef0>]
vprintk_emit+0x230/0x290
[  243.288830] hardirqs last disabled at (1626): [<c01a6f2c>]
vprintk_emit+0x26c/0x290
[  243.288906] softirqs last  enabled at (1012): [<c0101768>]
__do_softirq+0x500/0x63c
[  243.288978] softirqs last disabled at (1007): [<c01315b4>]
irq_exit+0x214/0x220
[  243.289055] ---[ end trace eeacda95eb7db60a ]---
[  243.289345] asix 3-1:1.0 eth0: Failed to write reg index 0x0000: -22
[  243.289466] asix 3-1:1.0 eth0: Failed to write Medium Mode mode to
0x0000: ffffffea
[  243.289540] asix 3-1:1.0 eth0: Link is Down
[  243.482809] usb 1-1: reset high-speed USB device number 2 using
exynos-ehci
[  243.647251] usb 3-1: reset high-speed USB device number 2 using xhci-hcd
[  244.847161] OOM killer enabled.
[  244.850221] Restarting tasks ... done.
[  244.861372] PM: suspend exit

real    0m13.050s
user    0m0.000s
sys     0m1.152s
root@target:~#

It looks that some kind of system suspend/resume integration for phylib
is not implemented.

Probably it is should be handled only by the asix driver. I'll take a
look in to it. Did interface was able to resume after printing some
warnings?

Nope. The network is not operational after suspend/resume cycle after 
applying this patch.

Best regards

-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland