Re: [PATCHv5][ 5/8] staging: imx-drm: parallel display: add regulator support.

[Marek Vasut <marex@denx.de>]

On Thursday, December 05, 2013 at 07:28:09 PM, Denis Carikli wrote:
> Cc: Dan Carpenter <dan.carpenter@oracle.com>
> Cc: Rob Herring <rob.herring@calxeda.com>
> Cc: Pawel Moll <pawel.moll@arm.com>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: Stephen Warren <swarren@wwwdotorg.org>
> Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
> Cc: devicetree@vger.kernel.org
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: driverdev-devel@linuxdriverproject.org
> Cc: David Airlie <airlied@linux.ie>
> Cc: dri-devel@lists.freedesktop.org
> Cc: Sascha Hauer <kernel@pengutronix.de>
> Cc: Shawn Guo <shawn.guo@linaro.org>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: Eric Bénard <eric@eukrea.com>
> Signed-off-by: Denis Carikli <denis@eukrea.com>
> ---
> ChangeLog v3->v5:
> - Code clenaup.
> 
> ChangeLog v2->v3:
> - Added some interested people in the Cc list.
> - the lcd-supply is now called display-supply (not all display are LCD).
> - The code and documentation was updated accordingly.
> - regulator_is_enabled now guard the regulator enables/disables because
>   regulator_disable does not check the regulator state.
> ---
>  .../bindings/staging/imx-drm/fsl-imx-drm.txt       |    1 +
>  drivers/staging/imx-drm/parallel-display.c         |   22
> ++++++++++++++++++++ 2 files changed, 23 insertions(+)
> 
> diff --git
> a/Documentation/devicetree/bindings/staging/imx-drm/fsl-imx-drm.txt
> b/Documentation/devicetree/bindings/staging/imx-drm/fsl-imx-drm.txt index
> 2d24425..4dd7ce5 100644
> --- a/Documentation/devicetree/bindings/staging/imx-drm/fsl-imx-drm.txt
> +++ b/Documentation/devicetree/bindings/staging/imx-drm/fsl-imx-drm.txt
> @@ -28,6 +28,7 @@ Required properties:
>  - compatible: Should be "fsl,imx-parallel-display"
>  - crtc: the crtc this display is connected to, see below
>  Optional properties:
> +- display-supply : phandle to the regulator device tree node if needed.
>  - interface_pix_fmt: How this display is connected to the
>    crtc. Currently supported types: "rgb24", "rgb565", "bgr666", "rgb666"
>  - edid: verbatim EDID data block describing attached display.
> diff --git a/drivers/staging/imx-drm/parallel-display.c
> b/drivers/staging/imx-drm/parallel-display.c index 65d0c18..61c0aeb 100644
> --- a/drivers/staging/imx-drm/parallel-display.c
> +++ b/drivers/staging/imx-drm/parallel-display.c
> @@ -22,6 +22,7 @@
>  #include <drm/drmP.h>
>  #include <drm/drm_fb_helper.h>
>  #include <drm/drm_crtc_helper.h>
> +#include <linux/regulator/consumer.h>
>  #include <linux/videodev2.h>
> 
>  #include "imx-drm.h"
> @@ -35,6 +36,7 @@ struct imx_parallel_display {
>  	struct drm_encoder encoder;
>  	struct imx_drm_encoder *imx_drm_encoder;
>  	struct device *dev;
> +	struct regulator *disp_reg;
>  	void *edid;
>  	int edid_len;
>  	u32 interface_pix_fmt;
> @@ -141,6 +143,13 @@ static void imx_pd_encoder_prepare(struct drm_encoder
> *encoder) {
>  	struct imx_parallel_display *imxpd = enc_to_imxpd(encoder);
> 
> +	if (!IS_ERR(imxpd->disp_reg) &&
> +	    !regulator_is_enabled(imxpd->disp_reg)) {
> +		if (regulator_enable(imxpd->disp_reg))
> +			dev_err(imxpd->dev,
> +				"Failed to enable regulator.\n");

I wonder, is this linebreak needed for this function call ?
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