Re: [PATCH v3 1/5] leds: lm3532: Fix brightness control for i2c mode

[Dan Murphy]

Hello

On 8/27/19 7:44 AM, Dan Murphy wrote:
> Tony
>
> On 8/27/19 7:18 AM, Pavel Machek wrote:
> > On Mon 2019-08-26 15:44:37, Tony Lindgren wrote:
> > > * Pavel Machek <pavel@xxxxxx> [190826 22:14]:
> > > > On Mon 2019-08-26 14:58:22, Tony Lindgren wrote:
> > > > > Hi,
> > > > >
> > > > > * Dan Murphy <dmurphy@xxxxxx> [190820 19:53]:
> > > > > > Fix the brightness control for I2C mode.  Instead of
> > > > > > changing the full scale current register update the ALS target
> > > > > > register for the appropriate banks.
> > > > > >
> > > > > > In addition clean up some code errors and random misspellings found
> > > > > > during coding.
> > > > > >
> > > > > > Tested on Droid4 as well as LM3532 EVM connected to a 
> > > > > > BeagleBoneBlack
> > > > > >
> > > > > > Fixes: e37a7f8d77e1 ("leds: lm3532: Introduce the lm3532 LED 
> > > > > > driver")
> > > > > > Reported-by: Pavel Machek <pavel@xxxxxx>
> > > > > > Signed-off-by: Dan Murphy <dmurphy@xxxxxx>
> > > > > > ---
> > > > > >
> > > > > > v3 - Removed register define updates - 
> > > > > > https://lore.kernel.org/patchwork/patch/1114542/
> > > > > Looks like starting with this patch in Linux next the LCD on droid4
> > > > > is so dim it's unreadable even with brightness set to 255. Setting
> > > > > brightness to 0 does blank it completely though.
> > > > >
> > > > > Did something maybe break with the various patch revisions or are
> > > > > we now missing some dts patch?
> > > > Maybe missing dts patch. We should provide maximum current the LED can
> > > > handle...
> > > Or i2c control is somehow broken and only als control now works?
>
> With only setting CONFIG_LEDS_LM3532=m to the next branch I get full 
> brightness with 255.
>
> I also see half brightness at 128 with the ramp down working.
>
> I am not able to reproduce this issue on my device.
Just to make sure my data was right I did a clean rebuild on commit 
1dbb9fb4082ce2a2f1cf9596881ddece062d15d0

from the led-next branch.

Just adding the above config flag.  I still cannot reproduce the issue

See attached pic

Dan

<snip>

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