Re: [PATCH] omap: hsmmc funtionality breaks when CONFIG_PM not define

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Ghorai, Sukumar wrote:

-----Original Message-----
From: Adrian Hunter [mailto:adrian.hunter@xxxxxxxxx]
Sent: Tuesday, July 20, 2010 2:10 PM
To: Ghorai, Sukumar
Cc: linux-mmc@xxxxxxxxxxxxxxx; linux-omap@xxxxxxxxxxxxxxx; Shilimkar,
Santosh; Chikkature Rajashekar, Madhusudhan; Andrew Morton
Subject: Re: [PATCH] omap: hsmmc funtionality breaks when CONFIG_PM not
define

Ghorai, Sukumar wrote:
Adrian,

-----Original Message-----
From: Adrian Hunter [mailto:adrian.hunter@xxxxxxxxx]
Sent: Tuesday, July 20, 2010 1:40 PM
To: Ghorai, Sukumar
Cc: linux-mmc@xxxxxxxxxxxxxxx; linux-omap@xxxxxxxxxxxxxxx; Shilimkar,
Santosh; Chikkature Rajashekar, Madhusudhan; Andrew Morton
Subject: Re: [PATCH] omap: hsmmc funtionality breaks when CONFIG_PM not
define

Ghorai, Sukumar wrote:
-----Original Message-----
From: Adrian Hunter [mailto:adrian.hunter@xxxxxxxxx]
Sent: Tuesday, July 20, 2010 12:39 PM
To: Ghorai, Sukumar
Cc: linux-mmc@xxxxxxxxxxxxxxx; linux-omap@xxxxxxxxxxxxxxx; Shilimkar,
Santosh; Chikkature Rajashekar, Madhusudhan; Andrew Morton
Subject: Re: [PATCH] omap: hsmmc funtionality breaks when CONFIG_PM
not
define

Sukumar Ghorai wrote:
    Issue if power_saving option passed from board file and
CONFIG_PM
not define.
    This is because hosts refer to wrong operation table and that
try
to
power save.

power_saving is not related to power management.  It should work with
or
without
CONFIG_PM.  What problem are you seeing?
[Ghorai] when CONFIG_PM is not defined but power_saving flag is TRUE,
then host operation table point to table which handles in state machine
as: ENABLE -> CARDSLEEP -> REGSLEEP -> DISABLED for power/clock cut.
And
do the reverse for the enable clock/power.
And power saving is not required and wont work when CONFIG_PM is not
enabled.

How is that a problem?  It would be useful to know what you need?
[Ghorai] do men when CONFIG_PM is not enabled still we should do power
saving in mmc?

Why not?

Because issue is iclk/fclk is quite depended on PRCM framework when we are
using omap_hsmmc_ps_ops operation table.

iclk is left alone.

fclk is manipulated with or without power_saving.

I still do not understand your problem sorry :-(
[Ghorai] thanks and need input again, we have two tables -
1. static const struct mmc_host_ops omap_hsmmc_ops = {
}
--> This is without CONFIG_PM, assumed.

No it is independent of CONFIG_PM

With CONFIG_PM
	- the driver will restore registers if the host controller
	has been powered off / on by PRCM
	- suspend / resume can be used


2. static const struct mmc_host_ops omap_hsmmc_ps_ops = {
}
-> this with CONFIG_PM, assumed.

No it is independent of CONFIG_PM

Without CONFIG_PM
	- card will be put to sleep after 1 second
	- card will be powered off after another 8 seconds


a. And you feel we should remove #1

Nothing should need to be removed.

b. use omap_hsmmc_ps_ops default.

With power_saving it is yes.

c. And it should work in all case?

It should work in all cases.


So if CONFIG_PM is not enable, then it should do simple clock
disable/enable, and not via the power state machine.

If that is what you want, simply change your board file:

#if CONFIG_PM
	.power_saving = true,
#else
	.power_saving = false,
#end
[Ghorai] the fix I send is to guard in MMC/SD host driver to avoid
mistake in board file(s). And this file is used for multiple omap3, omap4
boards.
Signed-off-by: Sukumar Ghorai <s-ghorai@xxxxxx>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
CC: Madhusudhan Chikkature <madhu.cr@xxxxxx>
CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
 Tested on omap3, omap4430 ES2.0

 drivers/mmc/host/omap_hsmmc.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/host/omap_hsmmc.c
b/drivers/mmc/host/omap_hsmmc.c
index b032828..f84eed0 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -2015,9 +2015,11 @@ static int __init omap_hsmmc_probe(struct
platform_device *pdev)
 	platform_set_drvdata(pdev, host);
 	INIT_WORK(&host->mmc_carddetect_work, omap_hsmmc_detect);

+#ifdef CONFIG_PM
 	if (mmc_slot(host).power_saving)
 		mmc->ops	= &omap_hsmmc_ps_ops;
 	else
+#endif
 		mmc->ops	= &omap_hsmmc_ops;

 	/*
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Regards,
Ghorai
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