Re: [PATCH] mmc: sdio: reset card during power_restore

[Ohad Ben-Cohen <ohad@wizery.com>]

On Thu, Jun 9, 2011 at 7:21 PM, Daniel Drake <dsd@laptop.org> wrote:
> With this version of the patch:
> http://dev.laptop.org/~dsd/20110609/sd-pwr-debug2.patch
>
> bash-4.1# mount -t debugfs none /sys/kernel/debug
> bash-4.1# cat /sys/kernel/debug/mmc1/ios
> clock:          0 Hz
> vdd:            0 (invalid)
> bus mode:       1 (open drain)
> chip select:    0 (don't care)
> power mode:     0 (off)
> bus width:      0 (1 bits)
> timing spec:    0 (legacy)
> bash-4.1#
> bash-4.1# insmod /media/4E11-1D7C/libertas_sdio.ko
> [   53.917466] libertas_sdio: Libertas SDIO driver
> [   53.922718] libertas_sdio: Copyright Pierre Ossman
> [   54.839032] libertas_sdio mmc1:0001:1: (unregistered net_device):
> 00:17:c4:a7:50:57, fw 9.70.3p36, cap 0x000003a3
> [   54.855479] libertas_sdio mmc1:0001:1: wlan0: Marvell WLAN 802.11 adapter
> bash-4.1# [   54.941099] udev[985]: renamed network interface wlan0 to eth0
> [   54.997656] ieee80211 phy0: assoc: bss   (null) not in scan results
> [   56.310846] ieee80211 phy0: assoc: bss   (null) not in scan results
> [   56.360840] cfg80211: Calling CRDA for country: EU

Looks good.

At this point everything works ?
(can you bring up the interface and scan/connect)

Can you now do a series of insmod-rmmod-insmod.. and see if things
always work (with no runtime pm errors) after you insmod ?

If yes, we're good.

> Note that the patch includes the mmc_select_voltage() call

Good, keep that one please.

> With a version of the patch that just does the reset, the post-powerup
> "vdd" figure does change:
> http://dev.laptop.org/~dsd/20110609/sd-pwr-debug3.patch
...
> bash-4.1# cat /sys/kernel/debug/mmc1/ios
> clock:          25000000 Hz
> vdd:            21 (3.3 ~ 3.4 V)

Without even looking exactly why it happens, it doesn't look too good.
I don't see a reason to stick to that version. Let's use the
mmc_select_voltage.

>
> For reference, here is the equivalent test performed without runtime
> PM enabled (i.e. all changes reverted)

you mean runtime PM disabled, right ?

Thanks,
Ohad.