2011-02-21 18:30:37

by Mark Brown

Subject: [PATCH] mfd: Put WM8994 into reset when suspending

Ensure that the chip is in the lowest power mode possible when suspended
by performing a soft reset on it. On early silicon revisions the lowest
power modes can't be entered without using reset so we can't achieve
equivalent results within the individual drivers.

Signed-off-by: Mark Brown <[email protected]>
---
drivers/mfd/wm8994-core.c | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/mfd/wm8994-core.c b/drivers/mfd/wm8994-core.c
index f4016a0..e673bda2 100644
--- a/drivers/mfd/wm8994-core.c
+++ b/drivers/mfd/wm8994-core.c
@@ -271,6 +271,11 @@ static int wm8994_suspend(struct device *dev)
if (ret < 0)
dev_err(dev, "Failed to save LDO registers: %d\n", ret);

+ /* Explicitly put the device into reset in case regulators
+ * don't get disabled in order to ensure consistent restart.
+ */
+ wm8994_reg_write(wm8994, WM8994_SOFTWARE_RESET, 0x8994);
+
wm8994->suspended = true;

ret = regulator_bulk_disable(wm8994->num_supplies,
--
1.7.2.3

2011-02-21 20:05:19

by Samuel Ortiz

Subject: Re: [PATCH] mfd: Put WM8994 into reset when suspending

Hi Mark,

On Mon, Feb 21, 2011 at 06:30:31PM +0000, Mark Brown wrote:
> Ensure that the chip is in the lowest power mode possible when suspended
> by performing a soft reset on it. On early silicon revisions the lowest
> power modes can't be entered without using reset so we can't achieve
> equivalent results within the individual drivers.
Patch applied, thanks.

Cheers,
Samuel.

--
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http://oss.intel.com/