On Tue, 12 Nov 2019 at 01:51, Doug Anderson <dianders@xxxxxxxxxxxx> wrote:
>
> Hi,
>
> On Sat, Nov 9, 2019 at 2:31 AM Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote:
> >
> > Changes in v2:
> > - Add adaptations to the mwifiex driver.
> > - Keep existing syncronous reset behaviour if the SDIO card has a single
> > func driver.
> >
> > It has turned out that it's not a good idea to try to power cycle and to
> > re-initialize the SDIO card, as currently done through mmc_hw_reset(). This
> > because there may be multiple SDIO funcs attached to the same SDIO card and
> > some of the others that didn't execute the call to mmc_hw_reset(), may then
> > simply experience an undefined behaviour.
> >
> > The following patches in this series attempts to address this problem, by
> > reworking the mmc_hw_reset() behaviour for SDIO and by adopting the Marvel
> > mwifiex driver to these changes.
> >
> > Note that, I don't have the HW at hand so the the code has only compile tested.
> > Test on HW is greatly appreciated!
> >
> > Ulf Hansson (3):
> > mwifiex: Re-work support for SDIO HW reset
> > mmc: core: Drop check for mmc_card_is_removable() in mmc_rescan()
> > mmc: core: Re-work HW reset for SDIO cards
> >
> > drivers/mmc/core/core.c | 12 +++-----
> > drivers/mmc/core/core.h | 2 ++
> > drivers/mmc/core/sdio.c | 28 ++++++++++++++++-
> > drivers/mmc/core/sdio_bus.c | 9 +++++-
> > drivers/net/wireless/marvell/mwifiex/main.c | 6 +++-
> > drivers/net/wireless/marvell/mwifiex/main.h | 1 +
> > drivers/net/wireless/marvell/mwifiex/sdio.c | 33 ++++++++++++++-------
> > include/linux/mmc/card.h | 1 +
> > 8 files changed, 70 insertions(+), 22 deletions(-)
>
> I put this on rk3288-veyron-jerry atop v5.4-rc7 and I could run my
> test case for a while, AKA I got over 50 cycles of:
>
> ---
>
> for i in $(seq 1000); do
> echo "LOOP $i --------"
> echo 1 > /sys/kernel/debug/mwifiex/mlan0/reset
>
> while true; do
> if ! ping6 -w15 -c1 "${GW}" >/dev/null 2>&1; then
> fail=$(( fail + 1 ))
> echo "Fail WiFi ${fail}"
> if [[ ${fail} == 3 ]]; then
> exit 1
> fi
> else
> fail=0
> break
> fi
> done
>
> hciconfig hci0 down
> sleep 1
> if ! hciconfig hci0 up; then
> echo "Fail BT"
> exit 1
> fi
>
> done
>
> ---
>
> NOTE: with no patches I couldn't even get my test case to pass w/out
> the BT bits and I swear that used to work before. ...but I didn't
> debug since the end result (with full card hotplug) is happy-working
> for me. I'll still use it as further argument that (IMO) full unplug
> / plug of the card is better it uses more standard code paths and is
> less likely to break. ;-)
>
> Tested-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Thanks, I add this to the series and make a re-spin.
What do you think about tagging the patches for stable?
I guess there is a risk that we may "break" the other two users of
mmc_hw_reset(). But, as I said, in that case those needs to be fixed
anyways.
Kind regards
Uffe
