drivers/media/usb/gspca/mars.c

Source file repositories/reference/linux-study-clean/drivers/media/usb/gspca/mars.c

File Facts

System
Linux kernel
Corpus path
drivers/media/usb/gspca/mars.c
Extension
.c
Size
10847 bytes
Lines
428
Domain
Driver Families
Bucket
drivers/media
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct sd {
	struct gspca_dev gspca_dev;	/* !! must be the first item */

	struct v4l2_ctrl *brightness;
	struct v4l2_ctrl *saturation;
	struct v4l2_ctrl *sharpness;
	struct v4l2_ctrl *gamma;
	struct { /* illuminator control cluster */
		struct v4l2_ctrl *illum_top;
		struct v4l2_ctrl *illum_bottom;
	};
	u8 jpeg_hdr[JPEG_HDR_SZ];
};

/* V4L2 controls supported by the driver */
static void setbrightness(struct gspca_dev *gspca_dev, s32 val);
static void setcolors(struct gspca_dev *gspca_dev, s32 val);
static void setgamma(struct gspca_dev *gspca_dev, s32 val);
static void setsharpness(struct gspca_dev *gspca_dev, s32 val);

static const struct v4l2_pix_format vga_mode[] = {
	{320, 240, V4L2_PIX_FMT_JPEG, V4L2_FIELD_NONE,
		.bytesperline = 320,
		.sizeimage = 320 * 240 * 3 / 8 + 590,
		.colorspace = V4L2_COLORSPACE_JPEG,
		.priv = 2},
	{640, 480, V4L2_PIX_FMT_JPEG, V4L2_FIELD_NONE,
		.bytesperline = 640,
		.sizeimage = 640 * 480 * 3 / 8 + 590,
		.colorspace = V4L2_COLORSPACE_JPEG,
		.priv = 1},
};

static const __u8 mi_data[0x20] = {
/*	 01    02   03     04    05    06    07    08 */
	0x48, 0x22, 0x01, 0x47, 0x10, 0x00, 0x00, 0x00,
/*	 09    0a   0b     0c    0d    0e    0f    10 */
	0x00, 0x01, 0x30, 0x01, 0x30, 0x01, 0x30, 0x01,
/*	 11    12   13     14    15    16    17    18 */
	0x30, 0x00, 0x04, 0x00, 0x06, 0x01, 0xe2, 0x02,
/*	 19    1a   1b     1c    1d    1e    1f    20 */
	0x82, 0x00, 0x20, 0x17, 0x80, 0x08, 0x0c, 0x00
};

/* write <len> bytes from gspca_dev->usb_buf */
static void reg_w(struct gspca_dev *gspca_dev,
		 int len)
{
	int alen, ret;

	if (gspca_dev->usb_err < 0)
		return;

	ret = usb_bulk_msg(gspca_dev->dev,
			usb_sndbulkpipe(gspca_dev->dev, 4),
			gspca_dev->usb_buf,
			len,
			&alen,
			500);	/* timeout in milliseconds */
	if (ret < 0) {
		pr_err("reg write [%02x] error %d\n",
		       gspca_dev->usb_buf[0], ret);
		gspca_dev->usb_err = ret;
	}
}

static void mi_w(struct gspca_dev *gspca_dev,
		 u8 addr,
		 u8 value)
{
	gspca_dev->usb_buf[0] = 0x1f;
	gspca_dev->usb_buf[1] = 0;			/* control byte */
	gspca_dev->usb_buf[2] = addr;
	gspca_dev->usb_buf[3] = value;

	reg_w(gspca_dev, 4);
}

static void setbrightness(struct gspca_dev *gspca_dev, s32 val)
{
	gspca_dev->usb_buf[0] = 0x61;
	gspca_dev->usb_buf[1] = val;
	reg_w(gspca_dev, 2);
}

static void setcolors(struct gspca_dev *gspca_dev, s32 val)
{
	gspca_dev->usb_buf[0] = 0x5f;
	gspca_dev->usb_buf[1] = val << 3;
	gspca_dev->usb_buf[2] = ((val >> 2) & 0xf8) | 0x04;

Annotation

Implementation Notes