Re: [PATCH v5 2/2] phy: fsl-imx8-mipi-dphy: Hook into runtime pm

From: Liu Ying
Date: Mon Apr 12 2021 - 05:43:57 EST


Hi Guido,

On Fri, 2021-04-09 at 13:40 +0200, Guido Günther wrote:
> This allows us to shut down the mipi power domain on the imx8. The
> alternative would be to drop the dphy from the mipi power domain in the
> SOCs device tree and only have the DSI host controller visible there but
> since the PD is mostly about the PHY that would defeat it's purpose.
>
> This allows to shut off the power domain when blanking the LCD panel:
>
> pm_genpd_summary before:
>
> domain status slaves
> /device runtime status
> ----------------------------------------------------------------------
> mipi on
> /devices/platform/soc@0/soc@0:bus@30800000/30a00300.dphy unsupported
> /devices/platform/soc@0/soc@0:bus@30800000/30a00000.mipi_dsi suspended
>
> after:
>
> mipi off-0
> /devices/platform/soc@0/soc@0:bus@30800000/30a00300.dphy suspended
> /devices/platform/soc@0/soc@0:bus@30800000/30a00000.mipi_dsi suspended
>
> Signed-off-by: Guido Günther <agx@xxxxxxxxxxx>
> ---
> drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c b/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> index a95572b397ca..f89a0c458499 100644
> --- a/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> @@ -14,6 +14,7 @@
> #include <linux/of_platform.h>
> #include <linux/phy/phy.h>
> #include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> #include <linux/regmap.h>
>
> /* DPHY registers */
> @@ -469,20 +470,32 @@ static int mixel_dphy_probe(struct platform_device *pdev)
>
> dev_set_drvdata(dev, priv);
>
> + pm_runtime_enable(dev);
> +
> phy = devm_phy_create(dev, np, &mixel_dphy_phy_ops);
> if (IS_ERR(phy)) {
> + pm_runtime_disable(&pdev->dev);

It's fine to just use 'dev'.

> dev_err(dev, "Failed to create phy %ld\n", PTR_ERR(phy));
> return PTR_ERR(phy);
> }
> phy_set_drvdata(phy, priv);
>
> phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
> + if (IS_ERR(phy_provider))
> + pm_runtime_disable(&pdev->dev);

Ditto.

With the above two addressed:

Reviewed-by: Liu Ying <victor.liu@xxxxxxx>

>
> return PTR_ERR_OR_ZERO(phy_provider);
> }
>
> +static int mixel_dphy_remove(struct platform_device *pdev)
> +{
> + pm_runtime_disable(&pdev->dev);
> + return 0;
> +}
> +
> static struct platform_driver mixel_dphy_driver = {
> .probe = mixel_dphy_probe,
> + .remove = mixel_dphy_remove,
> .driver = {
> .name = "mixel-mipi-dphy",
> .of_match_table = mixel_dphy_of_match,