lkml.org 
[lkml]   [2016]   [Nov]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation
On Mon, Oct 31, 2016 at 10:29:37AM +0100, Sascha Hauer wrote:
> > accesses. This is true for the ->config() callback, but not for the
> > ->set_enable() callback. Given that the ipg clock is not consistently
> > enabled for all register accesses we can assume that either it is not
> > required at all or that the current code does not work.
> > Remove the ipg clock code for now so that it's no longer in the way of
> > refactoring the driver.
>
> For reference:
>
> I verified on i.MX53 and i.MX25 that the ipg clock provided to the pwm
> driver is not needed when accessing registers. I would have to verify
> that on i.MX27 aswell, but I do not have a board handy at the moment.

Also on i.MX27 disabling the PWMs ipg_clk does not disable register
accesses.

Sascha

>
> The current assumption as discussed by Philipp and me is that the ipg
> clk is only needed when the pwm output is driven by the ipg clk
> (MX3_PWMCR[16:17] = MX3_PWMCR_CLKSRC_IPG)
>
> Sascha
>
> --
> Pengutronix e.K. | |
> Industrial Linux Solutions | http://www.pengutronix.de/ |
> Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
> Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
>
>

--
Pengutronix e.K. | |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |

\
 
 \ /
  Last update: 2016-11-01 09:59    [W:0.142 / U:0.088 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site