Re: [PATCH v4 3/6] mfd: ti_am335x_tscadc: Remove unwanted reg_se_cache save

[Sekhar Nori <nsekhar@ti.com>]

On Tuesday 18 November 2014 10:42 PM, Dmitry Torokhov wrote:
> On Tue, Nov 18, 2014 at 02:30:05PM +0000, Lee Jones wrote:
>> On Fri, 14 Nov 2014, Vignesh R wrote:
>>
>>> In one shot mode, sequencer automatically disables all enabled steps at
>>> the end of each cycle. (both ADC steps and TSC steps) Hence these steps
>>> need not be saved in reg_se_cache for clearing these steps at a later
>>> stage.
>>> Also, when ADC wakes up Sequencer should not be busy executing any of the
>>> config steps except for the charge step. Previously charge step was 1 ADC
>>> clock cycle and hence it was ignored.
>>>
>>> Signed-off-by: Vignesh R <vigneshr@ti.com>
>>> ---
>>>  drivers/mfd/ti_am335x_tscadc.c       | 7 +++++--
>>>  include/linux/mfd/ti_am335x_tscadc.h | 1 +
>>>  2 files changed, 6 insertions(+), 2 deletions(-)
>>
>> Code looks better now.
>>
>> Acked-by: Lee Jones <lee.jones@linaro.org>
>>
>> What's the plan for this series?
> 
> I am waiting for the interested parties to provide more feedback. So far
> I have seen a few reports saying that they see issues with the series
> applied.

I tested this using lcd7 cape connected to beaglebone black. The latest
kernel I could find on this board was a TI BSP based v3.14 kernel. So I
had to port these patches to that kernel. Cc Robert Nelson to see if he
knows about a more recent kernel supporting that cape.

I did not see any breakage with these patches applied although I did not
see any noticeable performance improvement as well.

I also tested along with continuous loop reading from
/sys/bus/iio/devices/iio:device0/in_voltage5_raw

I have pushed the kernel I used here in case anyone wants to take a look
at my porting.

http://git.ti.com/cgit/cgit.cgi/~nsekhar/ti-linux-kernel/nsekhar-ti-linux-kernel.git/log/?h=am335x-tsc-test

I also tested this series on AM335x EVM using the v3.18-rc5 kernel.
Again, no breakage but no improvement as well.

All testing was done using ts_test

FWIW, you can add:

Tested-by: Sekhar Nori <nsekhar@ti.com>

Thanks,
Sekhar