Subject: Re: [PATCH v1] net: stmmac: add to set device wake up flag when stmmac init phy

From: Jakub Kicinski <[email-masked]>
Date: Wed, 1 Mar 2023 20:29:17 -0800

On Wed,  1 Mar 2023 15:47:56 +0800 Rongguang Wei wrote:
> From: Rongguang Wei <[email-masked]>
> 
> When MAC is not support PMT, driver will check PHY's WoL capability
> and set device wakeup capability in stmmac_init_phy(). We can enable
> the WoL through ethtool, the driver would enable the device wake up
> flag. Now the device_may_wakeup() return true.
> 
> But if there is a way which enable the PHY's WoL capability derectly,
> like in BIOS. The driver would not know the enable thing and would not
> set the device wake up flag. The phy_suspend may failed like this:
> 
> [   32.409063] PM: dpm_run_callback(): mdio_bus_phy_suspend+0x0/0x50 returns -16
> [   32.409065] PM: Device stmmac-1:00 failed to suspend: error -16
> [   32.409067] PM: Some devices failed to suspend, or early wake event detected
> 
> Add to set the device wakeup enable flag according to the get_wol
> function result in PHY can fix the error in this scene.

Please add an appropriate Fixes tag and repost if you consider this
a bug fix, or repost next week with [PATCH net-next] for inclusion 
in Linux 6.3 if you're okay with the patch being treated as enabling 
the feature on more platforms (i.e. not a fix).