[PATCH 3/4] drm/mediatek: fix the wrong pixel clock when resolution is 4K
Bibby Hsieh
bibby.hsieh at mediatek.com
Mon Jul 25 01:37:50 PDT 2016
Hi, CK,
Thanks for your comments.
On Mon, 2016-07-25 at 14:49 +0800, CK Hu wrote:
> Hi, Bibby:
>
> On Mon, 2016-07-25 at 14:24 +0800, Bibby Hsieh wrote:
> > Hi, CK,
> >
> > Thanks for your comments.
> >
> > On Wed, 2016-07-20 at 15:57 +0800, CK Hu wrote:
> > > Hi, Bibby:
> > >
> > > Some comments inline.
> > >
> > > On Wed, 2016-07-20 at 12:03 +0800, Bibby Hsieh wrote:
> > > > From: Junzhi Zhao <junzhi.zhao at mediatek.com>
> > > >
> > > > Pixel clock should be 297MHz when resolution is 4K.
> > > >
> > > > Signed-off-by: Junzhi Zhao <junzhi.zhao at mediatek.com>
> > > > Signed-off-by: Bibby Hsieh <bibby.hsieh at mediatek.com>
> > > > ---
> > > > drivers/gpu/drm/mediatek/mtk_dpi.c | 184 +++++++++++++++++++++++++-----------
> > > > 1 file changed, 131 insertions(+), 53 deletions(-)
> > > >
>
> [snip...]
>
> > > >
> > > > +static int mt8173_parse_clk_from_dt(struct mtk_dpi *dpi, struct device_node *np)
> > > > +{
> > > > + int i;
> > > > +
> > > > + for (i = 0; i < ARRAY_SIZE(mtk_dpi_clk_names); i++) {
> > > > + dpi->clk[i] = of_clk_get_by_name(np,
> > > > + mtk_dpi_clk_names[i]);
> > > > + if (IS_ERR(dpi->clk[i]))
> > > > + return PTR_ERR(dpi->clk[i]);
> > > > + }
> > > > + return 0;
> > > > +}
> > >
> > > I think parsing device tree is a pure SW behavior. Would this vary for
> > > different MTK soc?
> > >
> > Yes
>
> I can not imaging that, so could you give me an example source code of
> other MTK soc for parse_clk_from_dt()?
>
I will do some changes according to your comments.
> > > > +
> > > > +
> > > > +static const struct mtk_dpi_conf mt8173_conf = {
> > > > + .parse_clk_from_dt = mt8173_parse_clk_from_dt,
> > > > + .clk_config = mt8173_clk_config,
> > > > +};
> > > > +
> > > > +static const struct of_device_id mtk_dpi_of_ids[] = {
> > > > + { .compatible = "mediatek,mt8173-dpi",
> > > > + .data = &mt8173_conf,
> > > > + },
> > > > + {}
> > > > +};
> > > > +
> > > > static int mtk_dpi_probe(struct platform_device *pdev)
> > > > {
> > > > struct device *dev = &pdev->dev;
> > > > struct mtk_dpi *dpi;
> > > > struct resource *mem;
> > > > + struct device_node *np = dev->of_node;
> > > > struct device_node *ep, *bridge_node = NULL;
> > > > int comp_id;
> > > > + const struct of_device_id *match;
> > > > + struct mtk_dpi_conf *conf;
> > > > int ret;
> > > >
> > > > + match = of_match_node(mtk_dpi_of_ids, dev->of_node);
> > > > + if (!match)
> > > > + return -ENODEV;
> > > > +
> > > > dpi = devm_kzalloc(dev, sizeof(*dpi), GFP_KERNEL);
> > > > if (!dpi)
> > > > return -ENOMEM;
> > > >
> > > > dpi->dev = dev;
> > > > + dpi->data = (void *)match->data;
> > > > + conf = (struct mtk_dpi_conf *)match->data;
> > > >
> > > > mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > > dpi->regs = devm_ioremap_resource(dev, mem);
> > > > @@ -679,24 +777,9 @@ static int mtk_dpi_probe(struct platform_device *pdev)
> > > > return ret;
> > > > }
> > > >
> > > > - dpi->engine_clk = devm_clk_get(dev, "engine");
> > > > - if (IS_ERR(dpi->engine_clk)) {
> > > > - ret = PTR_ERR(dpi->engine_clk);
> > > > - dev_err(dev, "Failed to get engine clock: %d\n", ret);
> > > > - return ret;
> > > > - }
> > > > -
> > > > - dpi->pixel_clk = devm_clk_get(dev, "pixel");
> > > > - if (IS_ERR(dpi->pixel_clk)) {
> > > > - ret = PTR_ERR(dpi->pixel_clk);
> > > > - dev_err(dev, "Failed to get pixel clock: %d\n", ret);
> > > > - return ret;
> > > > - }
> > > > -
> > > > - dpi->tvd_clk = devm_clk_get(dev, "pll");
> > > > - if (IS_ERR(dpi->tvd_clk)) {
> > > > - ret = PTR_ERR(dpi->tvd_clk);
> > > > - dev_err(dev, "Failed to get tvdpll clock: %d\n", ret);
> > > > + ret = conf->parse_clk_from_dt(dpi, np);
> > > > + if (ret) {
> > > > + dev_err(dev, "parse tvd div clk failed!");
> > > > return ret;
> > > > }
> > > >
> > > > @@ -754,11 +837,6 @@ static int mtk_dpi_remove(struct platform_device *pdev)
> > > > return 0;
> > > > }
> > > >
> > > > -static const struct of_device_id mtk_dpi_of_ids[] = {
> > > > - { .compatible = "mediatek,mt8173-dpi", },
> > > > - {}
> > > > -};
> > > > -
> > > > struct platform_driver mtk_dpi_driver = {
> > > > .probe = mtk_dpi_probe,
> > > > .remove = mtk_dpi_remove,
> > >
> > > Regards,
> > > CK
> > >
> >
>
>
> Regards,
> CK
> >
>
>
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