Re: [PATCH v1 2/5] drm/stm: dw_mipi_dsi-stm: add support of an optional regulator

From: Philippe CORNU <philippe.cornu@st.com>
To: Yannick FERTRE <yannick.fertre@st.com>,
	Benjamin GAIGNARD <benjamin.gaignard@st.com>,
	Vincent ABRIOU <vincent.abriou@st.com>,
	"David Airlie" <airlied@linux.ie>,
	Daniel Vetter <daniel@ffwll.ch>, Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Alexandre TORGUE <alexandre.torgue@st.com>,
	"dri-devel@lists.freedesktop.org"
	<dri-devel@lists.freedesktop.org>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"linux-stm32@st-md-mailman.stormreply.com" 
	<linux-stm32@st-md-mailman.stormreply.com>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v1 2/5] drm/stm: dw_mipi_dsi-stm: add support of an optional regulator
Date: Fri, 5 Apr 2019 16:34:35 +0000	[thread overview]
Message-ID: <f66fe75c-c288-82ef-71d7-5d15b9b8e4b3@st.com> (raw)
In-Reply-To: <1554279389-27377-3-git-send-email-yannick.fertre@st.com>

On 4/3/19 10:16 AM, Yannick Fertré wrote:
> Add support of an optional regulator for the phy part of the DSI
> controller.
> 
> Signed-off-by: Yannick Fertré <yannick.fertre@st.com>
> ---
>   drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 20 ++++++++++++++++++++
>   1 file changed, 20 insertions(+)
> 
> diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
> index a672b59..84703d0 100644
> --- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
> +++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
> @@ -9,6 +9,7 @@
>   #include <linux/clk.h>
>   #include <linux/iopoll.h>
>   #include <linux/module.h>
> +#include <linux/regulator/consumer.h>
>   #include <drm/drmP.h>
>   #include <drm/drm_mipi_dsi.h>
>   #include <drm/bridge/dw_mipi_dsi.h>
> @@ -76,6 +77,7 @@ struct dw_mipi_dsi_stm {
>   	u32 hw_version;
>   	int lane_min_kbps;
>   	int lane_max_kbps;
> +	struct regulator *vdd_supply;
>   };
>   
>   static inline void dsi_write(struct dw_mipi_dsi_stm *dsi, u32 reg, u32 val)
> @@ -318,16 +320,32 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
>   		return PTR_ERR(dsi->base);
>   	}
>   
> +	dsi->vdd_supply = devm_regulator_get_optional(dev, "phy-dsi");
> +	if (IS_ERR(dsi->vdd_supply)) {
> +		ret = PTR_ERR(dsi->vdd_supply);
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "failed to request regulator: %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = regulator_enable(dsi->vdd_supply);
> +	if (ret) {
> +		dev_err(dev, "failed to enable regulator: %d\n", ret);
> +		return ret;
> +	}
> +
>   	dsi->pllref_clk = devm_clk_get(dev, "ref");
>   	if (IS_ERR(dsi->pllref_clk)) {
>   		ret = PTR_ERR(dsi->pllref_clk);
>   		dev_err(dev, "Unable to get pll reference clock: %d\n", ret);
> +		regulator_disable(dsi->vdd_supply);
>   		return ret;
>   	}
>   
>   	ret = clk_prepare_enable(dsi->pllref_clk);
>   	if (ret) {
>   		dev_err(dev, "%s: Failed to enable pllref_clk\n", __func__);
> +		regulator_disable(dsi->vdd_supply);
>   		return ret;
>   	}
>   
> @@ -339,6 +357,7 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
>   	dsi->dsi = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
>   	if (IS_ERR(dsi->dsi)) {
>   		DRM_ERROR("Failed to initialize mipi dsi host\n");
> +		regulator_disable(dsi->vdd_supply);
>   		clk_disable_unprepare(dsi->pllref_clk);
>   		return PTR_ERR(dsi->dsi);
>   	}
> @@ -351,6 +370,7 @@ static int dw_mipi_dsi_stm_remove(struct platform_device *pdev)
>   	struct dw_mipi_dsi_stm *dsi = platform_get_drvdata(pdev);
>   
>   	clk_disable_unprepare(dsi->pllref_clk);
> +	regulator_disable(dsi->vdd_supply);

Dear Yannick,

Acked-by: Philippe Cornu <philippe.cornu@st.com>

Philippe

>   	dw_mipi_dsi_remove(dsi->dsi);
>   
>   	return 0;
> 