Hi, Thanks! I understand that this patch does potentially affect boards with external pull down. To avoid this, I will move `enable-strobe-pulldown` to rk3399-nanopi4.dtsi and send patch v2. BR, Jensen On Wed, Aug 24, 2022 at 10:58 PM Doug Anderson <dianders@xxxxxxxxxxxx> wrote: > > Hi, > > On Tue, Aug 23, 2022 at 8:11 PM Jensen Huang > <jensenhuang@xxxxxxxxxxxxxxx> wrote: > > > > Hi, > > > > Sorry for sending an email in HTML format. > > > > I realized that only some devices may be affected, so I considered > > modifying rk3399-nanopi4.dtsi only, > > but other boards without external pull-down should still need this patch. > > I guess the other alternative would be to change how the dt property > works. You could say: > > 1. If `enable-strobe-pulldown` is set then enable the strobe pulldown. > > 2. If `enable-strobe-pulldown` is not set then don't touch the pin in > the kernel. > > 3. If someone later needs to explicitly disable the strobe pulldown > they could add a new property like `disable-strobe-pulldown`. > > > Obviously there are tradeoffs between that and what you've done and > I'm happy to let others make the call of which they'd prefer. > > > > BR, > > Jensen > > > > On Tue, Aug 23, 2022 at 10:13 PM Doug Anderson <dianders@xxxxxxxxxxxx> wrote: > > > > > > Hi, > > > > > > On Tue, Aug 23, 2022 at 4:53 AM Heiko Stübner <heiko@xxxxxxxxx> wrote: > > > > > > > > Am Montag, 22. August 2022, 09:41:39 CEST schrieb Jensen Huang: > > > > > Internal pull-down for strobe line (GRF_EMMCPHY_CON2[9]) was disabled > > > > > by commit 8b5c2b45b8f0, which causes I/O error in HS400 mode. > > > > > > > > > > Tested on NanoPC-T4. > > > > > > > > > > Fixes: 8b5c2b45b8f0 ("phy: rockchip: set pulldown for strobe line in dts") > > > > > Signed-off-by: Jensen Huang <jensenhuang@xxxxxxxxxxxxxxx> > > > > > > > > ok, so this looks like it restores previous functionality. > > > > > > > > I'm just wondering as the "offending" patch is from 2020, why this > > > > only turns up now. Any ideas? > > > > > > Ah, I see. So before the offending patch we used to just leave the > > > pull state at whatever the default was when the kernel was booted. > > > After the offending patch we chose a default. > > > > > > On kevin I see an external pull down on this line. Enabling both the > > > internal and external is probably not a huge deal, it'll just affect > > > the strength of the pull. > > > > > > On bob I _think_ the external pull down is also stuffed. > > > > > > ...so I guess that would explain why it didn't cause a problem for at > > > least those two boards? > > > > > > -Doug