Hi Dean,
On Mon, Jan 08, 2024 at 04:49:21PM -0600, dean@xxxxxxxxxxxx wrote:
> On 2024-01-08 07:25, Laurent Pinchart wrote:
> > On Mon, Jan 08, 2024 at 12:52:44PM +0000, Sakari Ailus wrote:
> >> On Fri, Dec 15, 2023 at 11:14:21AM -0800, Dean Anderson wrote:
> >> > Adding V4L2 read-only control id for serial number as hardware
> >> > does not support embedding the serial number in the USB device descriptors.
> >> > Comment added noting v4l2_ctrl_handler_setup is not needed for this driver.
> >> >
> >> > Signed-off-by: Dean Anderson <dean@xxxxxxxxxxxx>
> >> >
> >> > ---
> >> > drivers/media/usb/s2255/s2255drv.c | 52 +++++++++++++++++++++++++++++-
> >> > 1 file changed, 51 insertions(+), 1 deletion(-)
> >> >
> >> > diff --git a/drivers/media/usb/s2255/s2255drv.c b/drivers/media/usb/s2255/s2255drv.c
> >> > index 3c2627712fe9..1f3961835711 100644
> >> > --- a/drivers/media/usb/s2255/s2255drv.c
> >> > +++ b/drivers/media/usb/s2255/s2255drv.c
> >>
> >> I'd document a new standardised control for this purpose. Any other
> >> opinions?
> >
> > How about reporting the serial number through struct
> > media_device_info.serial instead ?
>
> This is a great idea. My only concern is the CONFIG_MEDIA_CONTROLLER
> requirement, but most distros have that defined. I'll re-implement this
> patch with media_device_info.
>
> FYI, visl-core.c is missing several CONFIG_MEDIA_CONTROLLER ifdefs for
> media_device calls.
VIDEO_VISL select MEDIA_CONTROLLER, so the driver shouldn't need
#ifdef's.
> >> > /* frame prefix size (sent once every frame) */
> >> > #define PREFIX_SIZE 512
> >> > @@ -1232,6 +1234,36 @@ static int s2255_s_ctrl(struct v4l2_ctrl *ctrl)
> >> > return 0;
> >> > }
> >> >
> >> > +/*
> >> > + * serial number is not used in usb device descriptors.
> >> > + * returns serial number from device, 0 if none found.
> >> > + */
> >> > +
> >> > +static int s2255_g_serialnum(struct s2255_dev *dev)
> >> > +{
> >> > +#define S2255_SERIALNUM_NONE 0
> >>
> >> No need for such a definition, just assign it to zero.
> >>
> >> > +#define S2255_I2C_SIZE 16
> >> > +#define S2255_I2C_SERIALNUM 0xa2
> >> > +#define S2255_I2C_SERIALNUM_OFFSET 0x1ff0
> >> > +#define S2255_VENDOR_READREG 0x22
> >> > +
> >> > + u8 *buf;
> >> > + int serialnum = S2255_SERIALNUM_NONE;
> >>
> >> u32?
> >>
> >> > +
> >> > + buf = kzalloc(S2255_I2C_SIZE, GFP_KERNEL);
> >>
> >> Could this reside in the stack instead? It's just 16 bytes.
> >>
> >> > + if (!buf)
> >> > + return serialnum;
> >> > +
> >> > + s2255_vendor_req(dev, S2255_VENDOR_READREG, S2255_I2C_SERIALNUM_OFFSET,
> >> > + S2255_I2C_SERIALNUM >> 1, buf, S2255_I2C_SIZE, 0);
> >>
> >> It'd be nice to check for errors here.
> >>
> >> > +
> >> > + /* verify marker code */
> >> > + if (*(__le32 *)buf == S2255_MARKER_FIRMWARE)
> >> > + serialnum = (buf[12] << 24) + (buf[13] << 16) + (buf[14] << 8) + buf[15];
> >>
> >> Maybe:
> >>
> >> serialnum = be32_to_cpu(*(__be32 *)(buf + 12));
>
> yes
>
> >> You could add a reference to the serial number as a function argument and
> >> just return the error if one happens. This isn't exactly the same thing as
> >> having serial number 0.
> >>
> >> > + kfree(buf);
> >> > + return serialnum;
> >> > +}
> >> > +
> >> > static int vidioc_g_jpegcomp(struct file *file, void *priv,
> >> > struct v4l2_jpegcompression *jc)
> >> > {
> >> > @@ -1581,6 +1613,17 @@ static const struct v4l2_ctrl_config color_filter_ctrl = {
> >> > .def = 1,
> >> > };
> >> >
> >> > +static const struct v4l2_ctrl_config v4l2_ctrl_serialnum = {
> >> > + .ops = &s2255_ctrl_ops,
> >> > + .name = "Serial Number",
> >> > + .id = V4L2_CID_S2255_SERIALNUM,
> >> > + .type = V4L2_CTRL_TYPE_INTEGER,
> >> > + .max = 0x7fffffff,
> >> > + .min = 0,
> >> > + .step = 1,
> >> > + .flags = V4L2_CTRL_FLAG_READ_ONLY,
> >> > +};
> >> > +
> >> > static int s2255_probe_v4l(struct s2255_dev *dev)
> >> > {
> >> > int ret;
> >> > @@ -1588,6 +1631,7 @@ static int s2255_probe_v4l(struct s2255_dev *dev)
> >> > int cur_nr = video_nr;
> >> > struct s2255_vc *vc;
> >> > struct vb2_queue *q;
> >> > + struct v4l2_ctrl_config tmp = v4l2_ctrl_serialnum;
> >> >
> >> > ret = v4l2_device_register(&dev->interface->dev, &dev->v4l2_dev);
> >> > if (ret)
> >> > @@ -1598,7 +1642,7 @@ static int s2255_probe_v4l(struct s2255_dev *dev)
> >> > vc = &dev->vc[i];
> >> > INIT_LIST_HEAD(&vc->buf_list);
> >> >
> >> > - v4l2_ctrl_handler_init(&vc->hdl, 6);
> >> > + v4l2_ctrl_handler_init(&vc->hdl, 7);
> >> > v4l2_ctrl_new_std(&vc->hdl, &s2255_ctrl_ops,
> >> > V4L2_CID_BRIGHTNESS, -127, 127, 1, DEF_BRIGHT);
> >> > v4l2_ctrl_new_std(&vc->hdl, &s2255_ctrl_ops,
> >> > @@ -1615,6 +1659,8 @@ static int s2255_probe_v4l(struct s2255_dev *dev)
> >> > (dev->pid != 0x2257 || vc->idx <= 1))
> >> > v4l2_ctrl_new_custom(&vc->hdl, &color_filter_ctrl,
> >> > NULL);
> >> > + tmp.def = s2255_g_serialnum(dev);
> >> > + v4l2_ctrl_new_custom(&vc->hdl, &tmp, NULL);
> >> > if (vc->hdl.error) {
> >> > ret = vc->hdl.error;
> >> > v4l2_ctrl_handler_free(&vc->hdl);
> >> > @@ -2306,6 +2352,10 @@ static int s2255_probe(struct usb_interface *interface,
> >> > retval = s2255_board_init(dev);
> >> > if (retval)
> >> > goto errorBOARDINIT;
> >> > + /*
> >> > + * v4l2_ctrl_handler_setup is not required.
> >> > + * V4L2 controls initialized when firmware is loaded.
> >> > + */
> >>
> >> I'd drop the comment.
> >>
> >> > s2255_fwload_start(dev);
> >> > /* loads v4l specific */
> >> > retval = s2255_probe_v4l(dev);
--
Regards,
Laurent Pinchart
