Hi Dean,
Some comments below:
On 22/11/2023 20:48, Dean Anderson wrote:
> Adding V4L2 read-only control id for device id as hardware
> does not support embedding the device-id in the USB device descriptors.
>
> base-commit: 3e238417254bfdcc23fe207780b59cbb08656762
Just drop this line, it doesn't belong in a commit message.
>
> Signed-off-by: Dean Anderson <dean@xxxxxxxxxxxx>
>
> ---
> drivers/media/usb/s2255/s2255drv.c | 49 +++++++++++++++++++++++++++++-
> 1 file changed, 48 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/usb/s2255/s2255drv.c b/drivers/media/usb/s2255/s2255drv.c
> index 3c2627712fe9..c2248bbc7840 100644
> --- a/drivers/media/usb/s2255/s2255drv.c
> +++ b/drivers/media/usb/s2255/s2255drv.c
> @@ -40,7 +40,7 @@
> #include <media/v4l2-ctrls.h>
> #include <media/v4l2-event.h>
>
> -#define S2255_VERSION "1.25.1"
> +#define S2255_VERSION "1.26.1"
> #define FIRMWARE_FILE_NAME "f2255usb.bin"
>
> /* default JPEG quality */
> @@ -60,6 +60,7 @@
> #define S2255_MIN_BUFS 2
> #define S2255_SETMODE_TIMEOUT 500
> #define S2255_VIDSTATUS_TIMEOUT 350
> +#define S2255_MARKER_FIRMWARE cpu_to_le32(0xDDCCBBAAL)
> #define S2255_MARKER_FRAME cpu_to_le32(0x2255DA4AL)
> #define S2255_MARKER_RESPONSE cpu_to_le32(0x2255ACACL)
> #define S2255_RESPONSE_SETMODE cpu_to_le32(0x01)
> @@ -323,6 +324,7 @@ struct s2255_buffer {
> #define S2255_V4L2_YC_ON 1
> #define S2255_V4L2_YC_OFF 0
> #define V4L2_CID_S2255_COLORFILTER (V4L2_CID_USER_S2255_BASE + 0)
> +#define V4L2_CID_S2255_DEVICEID (V4L2_CID_USER_S2255_BASE + 1)
>
> /* frame prefix size (sent once every frame) */
> #define PREFIX_SIZE 512
> @@ -1232,6 +1234,37 @@ static int s2255_s_ctrl(struct v4l2_ctrl *ctrl)
> return 0;
> }
>
> +/* deviceid/serial number is not used in usb device descriptors.
> + * returns device-id/serial number from device, 0 if none found.
Please put the '/*' on a line by itself, that's consistent with the
coding style for multi-line comments.
Also run the patch through 'checkpatch.pl --strict'. I get several
warnings.
returns -> Returns
One question about this comment: is the Device ID the same as a serial
number? "Device ID" can mean either the ID of a device model, or a unique
ID for each device. If it is the latter, should it perhaps be called
"Device S/N" or just "Serial Number"?
> + */
> +#define S2255_DEVICEID_NONE 0
> +static int s2255_g_deviceid(struct s2255_dev *dev)
> +{
> + u8 *outbuf;
> + int rc;
> + int deviceid = S2255_DEVICEID_NONE;
> +#define S2255_I2C_SIZE 16
> + outbuf = kzalloc(S2255_I2C_SIZE * sizeof(u8), GFP_KERNEL);
Drop the "* sizeof(u8)", it serves no purpose.
> + if (outbuf == NULL)
> + return deviceid;
> +#define S2255_I2C_SNDEV 0xa2
> +#define S2255_I2C_SNOFFSET 0x1ff0
> +#define S2255_USBVENDOR_READREG 0x22
> + rc = s2255_vendor_req(dev, S2255_USBVENDOR_READREG, S2255_I2C_SNOFFSET,
> + S2255_I2C_SNDEV >> 1, outbuf, S2255_I2C_SIZE, 0);
> + if (rc < 0)
> + goto exit_g_deviceid;
> +
> + /* verify marker code */
> + if (*(__le32 *)outbuf != S2255_MARKER_FIRMWARE)
> + goto exit_g_deviceid;
> +
> + deviceid = (outbuf[12] << 24) + (outbuf[13] << 16) + (outbuf[14] << 8) + outbuf[15];
> +exit_g_deviceid:
> + kfree(outbuf);
> + return deviceid;
This is overly complicated. How about this:
/* verify marker code */
if (*(__le32 *)outbuf == S2255_MARKER_FIRMWARE)
deviceid = (outbuf[12] << 24) + (outbuf[13] << 16) + (outbuf[14] << 8) + outbuf[15];
kfree(outbuf);
return deviceid;
> +}
> +
> static int vidioc_g_jpegcomp(struct file *file, void *priv,
> struct v4l2_jpegcompression *jc)
> {
> @@ -1581,6 +1614,17 @@ static const struct v4l2_ctrl_config color_filter_ctrl = {
> .def = 1,
> };
>
> +static struct v4l2_ctrl_config v4l2_ctrl_deviceid = {
> + .ops = &s2255_ctrl_ops,
> + .name = "Device ID",
> + .id = V4L2_CID_S2255_DEVICEID,
> + .type = V4L2_CTRL_TYPE_INTEGER,
Please note that TYPE_INTEGER is a signed integer.
If you need an unsigned integer, then use TYPE_U32.
> + .max = 0xffffffff,
> + .min = 0,
> + .step = 1,
> + .flags = V4L2_CTRL_FLAG_READ_ONLY,
> +};
> +
> static int s2255_probe_v4l(struct s2255_dev *dev)
> {
> int ret;
> @@ -1615,6 +1659,9 @@ 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);
> + v4l2_ctrl_deviceid.def = s2255_g_deviceid(dev);
> + v4l2_ctrl_new_custom(&vc->hdl, &v4l2_ctrl_deviceid,
> + NULL);
> if (vc->hdl.error) {
> ret = vc->hdl.error;
> v4l2_ctrl_handler_free(&vc->hdl);
Regards,
Hans
