[RFC] omap: rx51: Set regulator V28 always on

[RFC] omap: rx51: Set regulator V28 always on

[Jarkko Nikula]

It seems that the battery cover sensor in Nokia N900 is powered from the
V28 domain. Now if this regulator is disabled it causes that the gpio 160
reads only zero which effectively causes uSD removal detection.

Currently the bootloader enabled V28 is kept on but this may change in the
future according to comment in
drivers/regulator/core.c: regulator_has_full_constraints.

Also if there are any consumers on the V28 domain doing regulator_enable
regulator_disable cycle the V28 will be disabled after that.

Prepare for these by defining the V28 as always_on regulator.

Signed-off-by: Jarkko Nikula <jhnikula@gmail.com>
Cc: Adrian Hunter <adrian.hunter@nokia.com>
---
This can be tested easily by setting full regulator constraints. Then the
regulator framework will disable in a late_initcall all the regulators with
zero use count and that don't have always_on flag set.

 void __init rx51_peripherals_init(void)
 {
+	regulator_has_full_constraints();
 	rx51_i2c_init();
 	board_onenand_init();
 	board_smc91x_init();
---
 arch/arm/mach-omap2/board-rx51-peripherals.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-omap2/board-rx51-peripherals.c b/arch/arm/mach-omap2/board-rx51-peripherals.c
index abdf321..aeeb91d 100644
--- a/arch/arm/mach-omap2/board-rx51-peripherals.c
+++ b/arch/arm/mach-omap2/board-rx51-peripherals.c
@@ -362,6 +362,7 @@ static struct regulator_init_data rx51_vaux1 = {
 		.name			= "V28",
 		.min_uV			= 2800000,
 		.max_uV			= 2800000,
+		.always_on		= true, /* due battery cover sensor */
 		.valid_modes_mask	= REGULATOR_MODE_NORMAL
 					| REGULATOR_MODE_STANDBY,
 		.valid_ops_mask		= REGULATOR_CHANGE_MODE
-- 
1.7.1

[APPLIED] [RFC] omap: rx51: Set regulator V28 always on

[Tony Lindgren]

This patch has been applied to the linux-omap
by youw fwiendly patch wobot.

Branch in linux-omap: devel-boards

Initial commit ID (Likely to change): 73eb91e9d948a5e6b682ac4ccabec16743321939

PatchWorks
http://patchwork.kernel.org/patch/107561/

Git (Likely to change, and takes a while to get mirrored)
http://git.kernel.org/?p=linux/kernel/git/tmlind/linux-omap-2.6.git;a=commit;h=73eb91e9d948a5e6b682ac4ccabec16743321939