linux-kernel - Re: [PATCH v2 1/3] media: i2c: ov5647: Convert to CCI register access helpers

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Message-ID: <20251229130116.GC6598@pendragon.ideasonboard.com>
Date: Mon, 29 Dec 2025 15:01:16 +0200
From: Laurent Pinchart <laurent.pinchart@...asonboard.com>
To: Tarang Raval <tarang.raval@...iconsignals.io>
Cc: Xiaolei Wang <xiaolei.wang@...driver.com>,
	"sakari.ailus@...ux.intel.com" <sakari.ailus@...ux.intel.com>,
	"dave.stevenson@...pberrypi.com" <dave.stevenson@...pberrypi.com>,
	"jacopo@...ndi.org" <jacopo@...ndi.org>,
	"mchehab@...nel.org" <mchehab@...nel.org>,
	"prabhakar.mahadev-lad.rj@...renesas.com" <prabhakar.mahadev-lad.rj@...renesas.com>,
	"hverkuil+cisco@...nel.org" <hverkuil+cisco@...nel.org>,
	"johannes.goede@....qualcomm.com" <johannes.goede@....qualcomm.com>,
	"hverkuil-cisco@...all.nl" <hverkuil-cisco@...all.nl>,
	"jai.luthra@...asonboard.com" <jai.luthra@...asonboard.com>,
	"linux-media@...r.kernel.org" <linux-media@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2 1/3] media: i2c: ov5647: Convert to CCI register
 access helpers

On Mon, Dec 29, 2025 at 12:37:41PM +0000, Tarang Raval wrote:
> > Use the new common CCI register access helpers to replace the private
> > register access helpers in the ov5647 driver. This simplifies the driver
> > by reducing the amount of code.
> > 
> > Signed-off-by: Xiaolei Wang <xiaolei.wang@...driver.com>
> > ---
> >  drivers/media/i2c/Kconfig  |   1 +
> >  drivers/media/i2c/ov5647.c | 997 +++++++++++++++++--------------------
> >  2 files changed, 453 insertions(+), 545 deletions(-)
> > 
> > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> > index 4b4db8c4f496..cce63349e71e 100644
> > --- a/drivers/media/i2c/Kconfig
> > +++ b/drivers/media/i2c/Kconfig
> > @@ -529,6 +529,7 @@ config VIDEO_OV5645
> > 
> >  config VIDEO_OV5647
> >         tristate "OmniVision OV5647 sensor support"
> > +       select V4L2_CCI_I2C
> >         help
> >           This is a Video4Linux2 sensor driver for the OmniVision
> >           OV5647 camera.
> > diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c
> > index e193fef4fced..fd69f1616794 100644
> > --- a/drivers/media/i2c/ov5647.c
> > +++ b/drivers/media/i2c/ov5647.c
> > @@ -22,6 +22,7 @@
> >  #include <linux/pm_runtime.h>
> >  #include <linux/slab.h>
> >  #include <linux/videodev2.h>
> > +#include <media/v4l2-cci.h>
> >  #include <media/v4l2-ctrls.h>
> >  #include <media/v4l2-device.h>
> >  #include <media/v4l2-event.h>
> > @@ -41,24 +42,19 @@
> >  #define MIPI_CTRL00_BUS_IDLE                   BIT(2)
> >  #define MIPI_CTRL00_CLOCK_LANE_DISABLE         BIT(0)
> > 
> > -#define OV5647_SW_STANDBY              0x0100
> > -#define OV5647_SW_RESET                        0x0103
> > -#define OV5647_REG_CHIPID_H            0x300a
> > -#define OV5647_REG_CHIPID_L            0x300b
> > -#define OV5640_REG_PAD_OUT             0x300d
> > -#define OV5647_REG_EXP_HI              0x3500
> > -#define OV5647_REG_EXP_MID             0x3501
> > -#define OV5647_REG_EXP_LO              0x3502
> > -#define OV5647_REG_AEC_AGC             0x3503
> > -#define OV5647_REG_GAIN_HI             0x350a
> > -#define OV5647_REG_GAIN_LO             0x350b
> > -#define OV5647_REG_VTS_HI              0x380e
> > -#define OV5647_REG_VTS_LO              0x380f
> > -#define OV5647_REG_FRAME_OFF_NUMBER    0x4202
> > -#define OV5647_REG_MIPI_CTRL00         0x4800
> > -#define OV5647_REG_MIPI_CTRL14         0x4814
> > -#define OV5647_REG_AWB                 0x5001
> > -#define OV5647_REG_ISPCTRL3D           0x503d
> > +#define OV5647_SW_STANDBY              CCI_REG8(0x0100)
> > +#define OV5647_SW_RESET                        CCI_REG8(0x0103)
> > +#define OV5647_REG_CHIPID              CCI_REG16(0x300a)
> > +#define OV5640_REG_PAD_OUT             CCI_REG8(0x300d)
> > +#define OV5647_REG_EXPOSURE            CCI_REG24(0x3500)
> > +#define OV5647_REG_AEC_AGC             CCI_REG8(0x3503)
> > +#define OV5647_REG_GAIN                        CCI_REG16(0x350b)
> 
> It should be 0x350a, not 0x350b.
> 
> > +#define OV5647_REG_VTS                 CCI_REG16(0x380e)
> > +#define OV5647_REG_FRAME_OFF_NUMBER    CCI_REG8(0x4202)
> > +#define OV5647_REG_MIPI_CTRL00         CCI_REG8(0x4800)
> > +#define OV5647_REG_MIPI_CTRL14         CCI_REG8(0x4814)
> > +#define OV5647_REG_AWB                 CCI_REG8(0x5001)
> > +#define OV5647_REG_ISPCTRL3D           CCI_REG8(0x503d)
> > 
> >  #define REG_TERM 0xfffe
> >  #define VAL_TERM 0xfe
> > @@ -81,23 +77,19 @@
> >  #define OV5647_EXPOSURE_DEFAULT                1000
> >  #define OV5647_EXPOSURE_MAX            65535
>  
> ...
> 
> > @@ -1435,6 +1335,13 @@ static int ov5647_probe(struct i2c_client *client)
> >         if (ret < 0)
> >                 goto ctrl_handler_free;
> > 
> > +       sensor->regmap = devm_cci_regmap_init_i2c(client, 16);
> > +       if (IS_ERR(sensor->regmap)) {
> > +               ret = PTR_ERR(sensor->regmap);
> > +               dev_err(dev, "failed to initialize CCI: %d\n", ret);
> 
> Use return dev_err_probe();

dev_err_probe() is fine, but goto entity_cleanup is needed.

> > +               goto entity_cleanup;
> > +       }
> > +
> >         ret = ov5647_power_on(dev);
> >         if (ret)
> >                 goto entity_cleanup;

-- 
Regards,

Laurent Pinchart