Re: [PATCH v8 3/5] media: stm32-dcmipp: STM32 DCMIPP camera interface driver

From: Alain Volmat <alain.volmat@foss.st.com>
To: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Hugues Fruchet <hugues.fruchet@foss.st.com>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Alexandre Torgue <alexandre.torgue@foss.st.com>,
	Russell King <linux@armlinux.org.uk>,
	Sakari Ailus <sakari.ailus@linux.intel.com>,
	Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	Dan Scally <dan.scally@ideasonboard.com>,
	<linux-media@vger.kernel.org>, <devicetree@vger.kernel.org>,
	<linux-stm32@st-md-mailman.stormreply.com>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v8 3/5] media: stm32-dcmipp: STM32 DCMIPP camera interface driver
Date: Mon, 27 Nov 2023 14:55:03 +0100	[thread overview]
Message-ID: <20231127135503.GA1423796@gnbcxd0016.gnb.st.com> (raw)
In-Reply-To: <ba856a09de62a6ddbf1c19d5fd502de1cbc3e273.camel@pengutronix.de>

Hi Philipp,

On Mon, Nov 27, 2023 at 12:38:21PM +0100, Philipp Zabel wrote:
> On Mi, 2023-11-22 at 08:39 +0100, Alain Volmat wrote:
> > From: Hugues Fruchet <hugues.fruchet@foss.st.com>
> > 
> > This V4L2 subdev driver enables Digital Camera Memory Interface
> > Pixel Processor(DCMIPP) of STMicroelectronics STM32 SoC series.
> > 
> > Signed-off-by: Hugues Fruchet <hugues.fruchet@foss.st.com>
> > Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
> > ---
> [...]
> > diff --git a/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-core.c b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-core.c
> > new file mode 100644
> > index 000000000000..28ddb26314c3
> > --- /dev/null
> > +++ b/drivers/media/platform/st/stm32/stm32-dcmipp/dcmipp-core.c
> > @@ -0,0 +1,604 @@
> [...]
> > +struct dcmipp_device {
> > +	/* The platform device */
> > +	struct platform_device		pdev;
> > +	struct device			*dev;
> > +
> > +	/* Hardware resources */
> > +	struct reset_control		*rstc;
> 
> As long as rstc is only used in dcmipp_probe(), there is no need to
> carry it around in struct dcmipp_device.

Oups, thanks.  Indeed, in first series reset was being used in another
place but this is no longer necessary now.  Thanks.

I fixed this and will push it into the v9.

Regards,
Alain
> 
> [...]
> > +static int dcmipp_probe(struct platform_device *pdev)
> > +{
> > +	struct dcmipp_device *dcmipp;
> > +	struct clk *kclk;
> 
> rstc could be a local variable here.
> 
> [...]
> 
> > +	/* Get hardware resources from devicetree */
> > +	dcmipp->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
> > +	if (IS_ERR(dcmipp->rstc))
> > +		return dev_err_probe(&pdev->dev, PTR_ERR(dcmipp->rstc),
> > +				     "Could not get reset control\n");
> [...]
> > +	/* Reset device */
> > +	ret = reset_control_assert(dcmipp->rstc);
> > +	if (ret) {
> > +		dev_err(&pdev->dev, "Failed to assert the reset line\n");
> > +		return ret;
> > +	}
> > +
> > +	usleep_range(3000, 5000);
> > +
> > +	ret = reset_control_deassert(dcmipp->rstc);
> > +	if (ret) {
> > +		dev_err(&pdev->dev, "Failed to deassert the reset line\n");
> > +		return ret;
> > +	}
> 
> regards
> Philipp