Messages in this thread |  | | Subject | Re: [PATCH v4 1/1] phy: fsl-imx8-mipi-dphy: Hook into runtime pm | From | Liu Ying <> | Date | Tue, 23 Feb 2021 10:36:58 +0800 |
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Hi Guido,
On Mon, 2021-02-22 at 19:38 +0100, 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 hen blanking the LCD panel:
s/hen/when/
> > 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@sigxcpu.org> > --- > drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c | 10 ++++++++++ > 1 file changed, 10 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..5de175695834 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 */ > @@ -469,6 +470,8 @@ static int mixel_dphy_probe(struct platform_device *pdev) > > dev_set_drvdata(dev, priv); > > + pm_runtime_enable(dev); > +
The runtime PM should be disabled if devm_phy_create() or devm_of_phy_provider_register() fail.
Also, I'm just realizing that mixel_dphy_configure() accesses some PHY registers, which likely needs the power domain on. However, the phy-core doesn't manage the runtime PM for phy_configure(). It looks that the NWL DSI bridge driver, which uses the PHY, enables the same power domain prior to the PHY configuration. That's probably why mixel_dphy_configure() gets power for accessing registers(if really needed). So, perhaps, either make phy_configure() manage runtime PM or get/put runtime PM in mixel_dphy_configure().
Regards, Liu Ying
> phy = devm_phy_create(dev, np, &mixel_dphy_phy_ops); > if (IS_ERR(phy)) { > dev_err(dev, "Failed to create phy %ld\n", PTR_ERR(phy)); > @@ -481,8 +484,15 @@ static int mixel_dphy_probe(struct platform_device *pdev) > 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,
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