lkml.org 
[lkml]   [2020]   [Mar]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v5 4/5] drm: imx: Add i.MX 6 MIPI DSI host platform driver
From
Date
Hello Fabio, Adrian:

On Mon, 2020-03-30 at 08:49 -0300, Fabio Estevam wrote:
> Hi Adrian,
>
> On Mon, Mar 30, 2020 at 8:34 AM Adrian Ratiu <adrian.ratiu@collabora.com> wrote:
> > This adds support for the Synopsis DesignWare MIPI DSI v1.01 host
> > controller which is embedded in i.MX 6 SoCs.
> >
> > Based on following patches, but updated/extended to work with existing
> > support found in the kernel:
> >
> > - drm: imx: Support Synopsys DesignWare MIPI DSI host controller
> > Signed-off-by: Liu Ying <Ying.Liu@freescale.com>
> >
> > - ARM: dtsi: imx6qdl: Add support for MIPI DSI host controller
> > Signed-off-by: Liu Ying <Ying.Liu@freescale.com>
>
> This one looks like a devicetree patch, but this patch does not touch
> devicetree.
>
> > + ret = clk_prepare_enable(dsi->pllref_clk);
> > + if (ret) {
> > + dev_err(dev, "%s: Failed to enable pllref_clk\n", __func__);
> > + return ret;
> > + }
> > +
> > + dsi->mux_sel = syscon_regmap_lookup_by_phandle(dev->of_node, "fsl,gpr");
> > + if (IS_ERR(dsi->mux_sel)) {
> > + ret = PTR_ERR(dsi->mux_sel);
> > + dev_err(dev, "%s: Failed to get GPR regmap: %d\n",
> > + __func__, ret);
> > + return ret;
>
> You should disable the dsi->pllref_clk clock prior to returning the error.
>

Another approach could be moving the clock on and off to
to component_ops.{bind,unbind} (as rockhip driver does).

What exactly is the PLL clock needed for? Would it make sense
to move it some of the PHY power on/off? (Maybe not, but it's worthing
checking).

Also, it seems the other IP blocks have this PLL clock, so maybe
it could be moved to the dw_mipi_dsi core? This could be something
for a follow-up, to avoid creeping this series.

Thanks,
Ezequiel

\
 
 \ /
  Last update: 2020-03-30 15:52    [W:0.069 / U:6.004 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site