ARM: tegra11: dvfs: Upgrade CL-DVFS disable output ops

New CL-DVFS h/w (rev A02 of Tegra11 SoC) allows to disable CL-DVFS
output while I2C transaction is in progress without compromising bus
integrity. This commit added to platform data configuration option
<out_quiet_then_disable> that is set only for older versions of the
chip.

In case when <out_quiet_then_disable> option is not set, a procedure
for exiting closed loop mode to open loop mode is modified as follows:
- I2C output is disabled before the switch (while still operating in
closed loop mode) to avoid unnecessary voltage jump to "safe value"
- Possible transaction in progress is flushed after interface is
disabled
- Flush timeout is reported to the caller that initiated closed loop
exit (bus integrity is guaranteed even if timeout happens)

In addition output is now disabled while look-up table is reloaded
in cosed loop mode to avoid race between table write (s/w) and read
(h/w).

Bug 1159200

Change-Id: I9d0f0dfa55664c5792ca81018c127628d461da0b
Signed-off-by: Alex Frid <afrid@nvidia.com>
Reviewed-on: http://git-master/r/198633
Reviewed-by: Mandar Padmawar <mpadmawar@nvidia.com>
Tested-by: Mandar Padmawar <mpadmawar@nvidia.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/arm/mach-tegra/board-dalmore-power.c b/arch/arm/mach-tegra/board-dalmore-power.c
index 2b1b7d026abb..b09368f4207b 100644
--- a/arch/arm/mach-tegra/board-dalmore-power.c
+++ b/arch/arm/mach-tegra/board-dalmore-power.c
@@ -42,6 +42,7 @@
 #include <mach/irqs.h>
 #include <mach/edp.h>
 #include <mach/gpio-tegra.h>
+#include <mach/hardware.h>
 
 #include "cpu-tegra.h"
 #include "pm.h"
@@ -1042,6 +1043,8 @@ static struct tegra_cl_dvfs_platform_data dalmore_cl_dvfs_data = {
 static int __init dalmore_cl_dvfs_init(void)
 {
 	fill_reg_map();
+	if (tegra_revision < TEGRA_REVISION_A02)
+		dalmore_cl_dvfs_data.out_quiet_then_disable = true;
 	tegra_cl_dvfs_device.dev.platform_data = &dalmore_cl_dvfs_data;
 	platform_device_register(&tegra_cl_dvfs_device);