Hi Guido,
this time hopefully with less broken quoting. My mailer is driving me
mad right now...
Am Mittwoch, dem 16.12.2020 um 12:27 +0100 schrieb Guido Günther:
> 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.
Adding RPM support is exactly the right course of action.
> This allows to shut off the power domain hen 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 <a...@sigxcpu.org>
> ---
> .../phy/freescale/phy-fsl-imx8-mipi-dphy.c | 22 ++++++++++++++++++-
> 1 file changed, 21 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> b/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> index a95572b397ca..34e2d801e520 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 */
> @@ -93,6 +94,7 @@ struct mixel_dphy_cfg {
> };
>
> struct mixel_dphy_priv {
> + struct device *dev;
> struct mixel_dphy_cfg cfg;
> struct regmap *regmap;
> struct clk *phy_ref_clk;
> @@ -382,6 +384,7 @@ static int mixel_dphy_power_on(struct phy *phy)
> ret = clk_prepare_enable(priv->phy_ref_clk);
> if (ret < 0)
> return ret;
> + pm_runtime_get_sync(priv->dev);
>
This call can fail and will leave you with an elevated rpm refcount.
Better use the new pm_runtime_resume_and_get to avoid this issue?
Nitpick: I would add a blank line before the call.
Regards,
Lucas
