* Ulf Hansson <ulf.hansson@xxxxxxxxxx> [190116 11:37]:
> During "wlan-up", we are programming the FW into the WiFi-chip. However,
> re-programming the FW doesn't work, unless a power cycle of the WiFi-chip
> is made in-between the programmings.
>
> To conform to this requirement and to fix the regression in a simple way,
> let's start by allowing that the SDIO card (WiFi-chip) may stay powered on
> (runtime resumed) when wl12xx_sdio_power_off() returns. The intent with the
> current code is to treat this scenario as an error, but unfortunate this
> doesn't work as expected, so let's fix this.
>
> The other part is to guarantee that a power cycle of the SDIO card has been
> completed when wl12xx_sdio_power_on() returns, as to allow the FW
> programming to succeed. However, relying solely on runtime PM to deal with
> this isn't sufficient. For example, userspace may prevent runtime suspend
> via sysfs for the device that represents the SDIO card, leading to that the
> mmc core also keeps it powered on. For this reason, let's instead do a
> brute force power cycle in wl12xx_sdio_power_on().
>
> Fixes: 728a9dc61f13 ("wlcore: sdio: Fix flakey SDIO runtime PM handling")
> Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> ---
>
> Changes in v2:
> - Keep the SDIO host claimed when calling mmc_hw_reset().
> - Add a fixes tag.
This v2 version works for me as tested with:
# while [ 1 ]; do ifconfig wlan0 down; ifconfig wlan0 up; done
[ 181.364990] wlcore: down
[ 182.116424] wlcore: firmware booted (Rev 6.3.10.0.141)
[ 182.151641] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
[ 182.166778] wlcore: down
[ 182.773132] wlcore: firmware booted (Rev 6.3.10.0.141)
[ 182.811096] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
...
Thanks for fixing this issue properly, and feel free to add:
Tested-by: Tony Lindgren <tony@xxxxxxxxxxx>
