Re: [PATCH] userspace API definitions for auto-focus coil

From: Pavel Machek
Date: Mon Jun 13 2016 - 15:18:03 EST

On Sun 2016-06-12 14:22:53, Sakari Ailus wrote:
> Hi Pavel,
>
> On Sun, Jun 12, 2016 at 10:48:11AM +0200, Pavel Machek wrote:
> > Hi!
> >
> > > > >Add userspace API definitions.
> > > > >
> > > > >Signed-off-by: Pavel Machek <pavel@xxxxxx>
> > > > >
> > > > >diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
> > > > >index b6a357a..23011cc 100644
> > > > >--- a/include/uapi/linux/v4l2-controls.h
> > > > >+++ b/include/uapi/linux/v4l2-controls.h
> > > > >@@ -974,4 +975,9 @@ enum v4l2_detect_md_mode {
> > > > > #define V4L2_CID_DETECT_MD_THRESHOLD_GRID (V4L2_CID_DETECT_CLASS_BASE + 3)
> > > > > #define V4L2_CID_DETECT_MD_REGION_GRID (V4L2_CID_DETECT_CLASS_BASE + 4)
> > > > >
> > > > >+/* Control IDs specific to the AD5820 driver as defined by V4L2 */
> > > > >+#define V4L2_CID_FOCUS_AD5820_BASE (V4L2_CTRL_CLASS_CAMERA | 0x10af)
> > >
> > > Please check V4L2_CID_USER_*_BASE. That's how custom controls are handled
> > > nowadays.
> >
> > So something like this?
> >
> > Thanks,
> > Pavel
> >
> > diff --git a/drivers/media/i2c/ad5820.c b/drivers/media/i2c/ad5820.c
> > index 2efa5dc1..b04b471 100644
> > --- a/drivers/media/i2c/ad5820.c
> > +++ b/drivers/media/i2c/ad5820.c
> > @@ -40,6 +40,11 @@
> > #define AD5820_RAMP_MODE_LINEAR (0 << 3)
> > #define AD5820_RAMP_MODE_64_16 (1 << 3)
> >
> > +/* Control IDs specific to the AD5820 driver as defined by V4L2 */
> > +#define V4L2_CID_FOCUS_AD5820_RAMP_TIME (V4L2_CID_USER_AD5820_BASE+0)
> > +#define V4L2_CID_FOCUS_AD5820_RAMP_MODE (V4L2_CID_FOCUS_AD5820_BASE+1)
> > +
> > +
>
> We could still define these in a header file that can be included by the
> user space. Please use V4L2_CID_AD5820 prefix.

Not V4L2_CID_USER_AD5820...?

> A separate header file should be used,
> e.g. include/uapi/linux/ad5820.h.

Ok, separate header file for 2 lines seemed like a bit of overkill,
but why not.

Something like this?

commit 8dd701d2580e41b06bb2285e6bd59a4f1702b4d8
Author: Pavel <pavel@xxxxxx>
Date: Mon Jun 13 21:17:15 2016 +0200

Userspace api, as Sakari asked.

diff --git a/drivers/media/i2c/ad5820.c b/drivers/media/i2c/ad5820.c
index 2efa5dc1..ed3facc 100644
--- a/drivers/media/i2c/ad5820.c
+++ b/drivers/media/i2c/ad5820.c
@@ -32,6 +32,8 @@
#include <media/v4l2-device.h>
#include <media/v4l2-subdev.h>

+#include <uapi/linux/ad5820.h>
+
#define AD5820_NAME "ad5820"

/* Register definitions */
@@ -40,6 +42,8 @@
#define AD5820_RAMP_MODE_LINEAR (0 << 3)
#define AD5820_RAMP_MODE_64_16 (1 << 3)

+
+
#define CODE_TO_RAMP_US(s) ((s) == 0 ? 0 : (1 << ((s) - 1)) * 50)
#define RAMP_US_TO_CODE(c) fls(((c) + ((c)>>1)) / 50)

@@ -165,13 +169,13 @@ static int ad5820_set_ctrl(struct v4l2_ctrl *ctrl)
coil->focus_absolute = ctrl->val;
return ad5820_update_hw(coil);

- case V4L2_CID_FOCUS_AD5820_RAMP_TIME:
+ case V4L2_CID_AD5820_RAMP_TIME:
code = RAMP_US_TO_CODE(ctrl->val);
ctrl->val = CODE_TO_RAMP_US(code);
coil->focus_ramp_time = ctrl->val;
break;

- case V4L2_CID_FOCUS_AD5820_RAMP_MODE:
+ case V4L2_CID_AD5820_RAMP_MODE:
coil->focus_ramp_mode = ctrl->val;
break;
}
@@ -191,7 +195,7 @@ static const char * const ad5820_focus_menu[] = {
static const struct v4l2_ctrl_config ad5820_ctrls[] = {
{
.ops = &ad5820_ctrl_ops,
- .id = V4L2_CID_FOCUS_AD5820_RAMP_TIME,
+ .id = V4L2_CID_AD5820_RAMP_TIME,
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "Focus ramping time [us]",
.min = 0,
@@ -202,7 +206,7 @@ static const struct v4l2_ctrl_config ad5820_ctrls[] = {
},
{
.ops = &ad5820_ctrl_ops,
- .id = V4L2_CID_FOCUS_AD5820_RAMP_MODE,
+ .id = V4L2_CID_AD5820_RAMP_MODE,
.type = V4L2_CTRL_TYPE_MENU,
.name = "Focus ramping mode",
.min = 0,
diff --git a/include/uapi/linux/ad5820.h b/include/uapi/linux/ad5820.h
new file mode 100644
index 0000000..d44ba9c
--- /dev/null
+++ b/include/uapi/linux/ad5820.h
@@ -0,0 +1,18 @@
+/*
+ * AD5820 DAC driver for camera voice coil focus.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ */
+
+#ifndef __LINUX_AD5820_H
+#define __LINUX_AD5820_H
+
+#include <linux/v4l2-controls.h>
+
+/* Control IDs specific to the AD5820 driver as defined by V4L2 */
+#define V4L2_CID_AD5820_RAMP_TIME (V4L2_CID_AD5820_BASE+0)
+#define V4L2_CID_AD5820_RAMP_MODE (V4L2_CID_AD5820_BASE+1)
+
+#endif
diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
index 23011cc..015e90b 100644
--- a/include/uapi/linux/v4l2-controls.h
+++ b/include/uapi/linux/v4l2-controls.h
@@ -181,6 +181,10 @@ enum v4l2_colorfx {
* We reserve 16 controls for this driver. */
#define V4L2_CID_USER_TC358743_BASE (V4L2_CID_USER_BASE + 0x1080)

+/* The base for the ad5820 driver controls.
+ * We reserve 16 controls for this driver. */
+#define V4L2_CID_AD5820_BASE (V4L2_CID_USER_BASE + 0x1090)
+
/* MPEG-class control IDs */
/* The MPEG controls are applicable to all codec controls
* and the 'MPEG' part of the define is historical */
@@ -986,9 +990,4 @@ enum v4l2_detect_md_mode {
#define V4L2_CID_MODE_SENSITIVITY (V4L2_CID_MODE_CLASS_BASE+6)
#define V4L2_CID_MODE_OPSYSCLOCK (V4L2_CID_MODE_CLASS_BASE+7)

-/* Control IDs specific to the AD5820 driver as defined by V4L2 */
-#define V4L2_CID_FOCUS_AD5820_BASE (V4L2_CTRL_CLASS_CAMERA | 0x10af)
-#define V4L2_CID_FOCUS_AD5820_RAMP_TIME (V4L2_CID_FOCUS_AD5820_BASE+0)
-#define V4L2_CID_FOCUS_AD5820_RAMP_MODE (V4L2_CID_FOCUS_AD5820_BASE+1)
-
#endif


--
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(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html