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3 commits

Author SHA1 Message Date
Anders Larsen
317aa408d6 ARM: 5975/1: AT91 slow-clock suspend: don't wait when turning PLLs off
From: Julien Langer <julien.langer@gmail.com>

AT91: when turning off the PLLs during suspend, don't wait for the lock
flag to be set. Previously the code would always run into the loop
limitation of 1000 iterations because the flag is never set when turning
the PLLs off.

Comments from Anders Larsen:

 (in http://marc.info/?l=linux-kernel&m=127058929724193&w=2)

Signed-off-by: Julien Langer <julien.langer@gmail.com>
Signed-off-by: Anders Larsen <al@alarsen.net>
Acked-by: Andrew Victor <linux@maxim.org.za>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-04-14 11:08:43 +01:00
Anders Larsen
9823f1a846 ARM: 6043/1: AT91 slow-clock resume: Don't wait for a disabled PLL to lock
at91 slow-clock resume: Don't wait for a disabled PLL to lock.

We run into this problem with the PLLB on the at91: ohci-at91 disables
the PLLB when going to suspend. The slowclock code however tries to do
the same: It saves the PLLB register value and when restoring the value
during resume, it waits for the PLLB to lock again. However the PLL will
never lock and the loop would run into its timeout because the slowclock
code just stored and restored an empty register.
This fixes the problem by only restoring PLLA/PLLB when they were enabled
at suspend time.

Cc: Andrew Victor <avictor.za@gmail.com>
Signed-off-by: Anders Larsen <al@alarsen.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-04-09 08:31:04 +01:00
Andrew Victor
eaad2db03c [ARM] 5264/2: [AT91] Suspend-to-RAM disables main oscillator
This patch adds support for a low(er)-power suspend-to-RAM.
In addition to the SDRAM being put into self-refresh mode, the Master
Clock is set to the Slow-clock rate (32Khz) and PLLA & PLLB are
disabled.
Certain peripherals are therefore also disabled, and thus cannot be
used as wakeup sources.

This patch has been included in the AT91 patches in various forms
since 2.6.19 and a number of people have worked or commented on it,
most notably:
 Savin Zlobec (for the original AT91RM9200 support)
 Anti Sullin (for the SAM9260 version)
 David Brownell, etc.

Signed-off-by: Andrew Victor <linux@maxim.org.za>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-21 23:01:01 +01:00