+static int em28xx_vbi_supported(struct em28xx *dev)
+{
+ /* Modprobe option to manually disable */
+ if (disable_vbi == 1)
+ return 0;
+
+ if (dev->board.is_webcam)
+ return 0;
+
+ /* FIXME: check subdevices for VBI support */
+
+ if (dev->chip_id == CHIP_ID_EM2860 ||
+ dev->chip_id == CHIP_ID_EM2883)
+ return 1;
+
+ /* Version of em28xx that does not support VBI */
+ return 0;
+}
+
+/*
+ * em28xx_wake_i2c()
+ * configure i2c attached devices
+ */
+static void em28xx_wake_i2c(struct em28xx *dev)
+{
+ v4l2_device_call_all(&dev->v4l2_dev, 0, core, reset, 0);
+ v4l2_device_call_all(&dev->v4l2_dev, 0, video, s_routing,
+ INPUT(dev->ctl_input)->vmux, 0, 0);
+ v4l2_device_call_all(&dev->v4l2_dev, 0, video, s_stream, 0);
+}
+
+static int em28xx_colorlevels_set_default(struct em28xx *dev)
+{
+ em28xx_write_reg(dev, EM28XX_R20_YGAIN, CONTRAST_DEFAULT);
+ em28xx_write_reg(dev, EM28XX_R21_YOFFSET, BRIGHTNESS_DEFAULT);
+ em28xx_write_reg(dev, EM28XX_R22_UVGAIN, SATURATION_DEFAULT);
+ em28xx_write_reg(dev, EM28XX_R23_UOFFSET, BLUE_BALANCE_DEFAULT);
+ em28xx_write_reg(dev, EM28XX_R24_VOFFSET, RED_BALANCE_DEFAULT);
+ em28xx_write_reg(dev, EM28XX_R25_SHARPNESS, SHARPNESS_DEFAULT);
+
+ em28xx_write_reg(dev, EM28XX_R14_GAMMA, 0x20);
+ em28xx_write_reg(dev, EM28XX_R15_RGAIN, 0x20);
+ em28xx_write_reg(dev, EM28XX_R16_GGAIN, 0x20);
+ em28xx_write_reg(dev, EM28XX_R17_BGAIN, 0x20);
+ em28xx_write_reg(dev, EM28XX_R18_ROFFSET, 0x00);
+ em28xx_write_reg(dev, EM28XX_R19_GOFFSET, 0x00);
+ return em28xx_write_reg(dev, EM28XX_R1A_BOFFSET, 0x00);
+}
+
+static int em28xx_set_outfmt(struct em28xx *dev)
+{
+ int ret;
+ u8 fmt, vinctrl;
+
+ fmt = dev->format->reg;
+ if (!dev->is_em25xx)
+ fmt |= 0x20;
+ /*
+ * NOTE: it's not clear if this is really needed !
+ * The datasheets say bit 5 is a reserved bit and devices seem to work
+ * fine without it. But the Windows driver sets it for em2710/50+em28xx
+ * devices and we've always been setting it, too.
+ *
+ * em2765 (em25xx, em276x/7x/8x) devices do NOT work with this bit set,
+ * it's likely used for an additional (compressed ?) format there.
+ */
+ ret = em28xx_write_reg(dev, EM28XX_R27_OUTFMT, fmt);
+ if (ret < 0)
+ return ret;
+
+ ret = em28xx_write_reg(dev, EM28XX_R10_VINMODE, dev->vinmode);
+ if (ret < 0)
+ return ret;
+
+ vinctrl = dev->vinctl;
+ if (em28xx_vbi_supported(dev) == 1) {
+ vinctrl |= EM28XX_VINCTRL_VBI_RAW;
+ em28xx_write_reg(dev, EM28XX_R34_VBI_START_H, 0x00);
+ em28xx_write_reg(dev, EM28XX_R36_VBI_WIDTH, dev->vbi_width/4);
+ em28xx_write_reg(dev, EM28XX_R37_VBI_HEIGHT, dev->vbi_height);
+ if (dev->norm & V4L2_STD_525_60) {
+ /* NTSC */
+ em28xx_write_reg(dev, EM28XX_R35_VBI_START_V, 0x09);
+ } else if (dev->norm & V4L2_STD_625_50) {
+ /* PAL */
+ em28xx_write_reg(dev, EM28XX_R35_VBI_START_V, 0x07);
+ }
+ }
+
+ return em28xx_write_reg(dev, EM28XX_R11_VINCTRL, vinctrl);
+}
+
+static int em28xx_accumulator_set(struct em28xx *dev, u8 xmin, u8 xmax,
+ u8 ymin, u8 ymax)
+{
+ em28xx_videodbg("em28xx Scale: (%d,%d)-(%d,%d)\n",
+ xmin, ymin, xmax, ymax);
+
+ em28xx_write_regs(dev, EM28XX_R28_XMIN, &xmin, 1);
+ em28xx_write_regs(dev, EM28XX_R29_XMAX, &xmax, 1);
+ em28xx_write_regs(dev, EM28XX_R2A_YMIN, &ymin, 1);
+ return em28xx_write_regs(dev, EM28XX_R2B_YMAX, &ymax, 1);
+}
+
+static void em28xx_capture_area_set(struct em28xx *dev, u8 hstart, u8 vstart,
+ u16 width, u16 height)
+{
+ u8 cwidth = width >> 2;
+ u8 cheight = height >> 2;
+ u8 overflow = (height >> 9 & 0x02) | (width >> 10 & 0x01);
+ /* NOTE: size limit: 2047x1023 = 2MPix */
+
+ em28xx_videodbg("capture area set to (%d,%d): %dx%d\n",
+ hstart, vstart,
+ ((overflow & 2) << 9 | cwidth << 2),
+ ((overflow & 1) << 10 | cheight << 2));
+
+ em28xx_write_regs(dev, EM28XX_R1C_HSTART, &hstart, 1);
+ em28xx_write_regs(dev, EM28XX_R1D_VSTART, &vstart, 1);
+ em28xx_write_regs(dev, EM28XX_R1E_CWIDTH, &cwidth, 1);
+ em28xx_write_regs(dev, EM28XX_R1F_CHEIGHT, &cheight, 1);
+ em28xx_write_regs(dev, EM28XX_R1B_OFLOW, &overflow, 1);
+
+ /* FIXME: function/meaning of these registers ? */
+ /* FIXME: align width+height to multiples of 4 ?! */
+ if (dev->is_em25xx) {
+ em28xx_write_reg(dev, 0x34, width >> 4);
+ em28xx_write_reg(dev, 0x35, height >> 4);
+ }
+}
+
+static int em28xx_scaler_set(struct em28xx *dev, u16 h, u16 v)
+{
+ u8 mode;
+ /* the em2800 scaler only supports scaling down to 50% */
+
+ if (dev->board.is_em2800) {
+ mode = (v ? 0x20 : 0x00) | (h ? 0x10 : 0x00);
+ } else {
+ u8 buf[2];
+
+ buf[0] = h;
+ buf[1] = h >> 8;
+ em28xx_write_regs(dev, EM28XX_R30_HSCALELOW, (char *)buf, 2);
+
+ buf[0] = v;
+ buf[1] = v >> 8;
+ em28xx_write_regs(dev, EM28XX_R32_VSCALELOW, (char *)buf, 2);
+ /* it seems that both H and V scalers must be active
+ to work correctly */
+ mode = (h || v) ? 0x30 : 0x00;
+ }
+ return em28xx_write_reg_bits(dev, EM28XX_R26_COMPR, mode, 0x30);
+}
+
+/* FIXME: this only function read values from dev */
+static int em28xx_resolution_set(struct em28xx *dev)
+{
+ int width, height;
+ width = norm_maxw(dev);
+ height = norm_maxh(dev);
+
+ /* Properly setup VBI */
+ dev->vbi_width = 720;
+ if (dev->norm & V4L2_STD_525_60)
+ dev->vbi_height = 12;
+ else
+ dev->vbi_height = 18;
+
+ em28xx_set_outfmt(dev);
+
+ em28xx_accumulator_set(dev, 1, (width - 4) >> 2, 1, (height - 4) >> 2);
+
+ /* If we don't set the start position to 2 in VBI mode, we end up
+ with line 20/21 being YUYV encoded instead of being in 8-bit
+ greyscale. The core of the issue is that line 21 (and line 23 for
+ PAL WSS) are inside of active video region, and as a result they
+ get the pixelformatting associated with that area. So by cropping
+ it out, we end up with the same format as the rest of the VBI
+ region */
+ if (em28xx_vbi_supported(dev) == 1)
+ em28xx_capture_area_set(dev, 0, 2, width, height);
+ else
+ em28xx_capture_area_set(dev, 0, 0, width, height);
+
+ return em28xx_scaler_set(dev, dev->hscale, dev->vscale);
+}
+
+/* Set USB alternate setting for analog video */
+static int em28xx_set_alternate(struct em28xx *dev)
+{
+ int errCode;
+ int i;
+ unsigned int min_pkt_size = dev->width * 2 + 4;
+
+ /* NOTE: for isoc transfers, only alt settings > 0 are allowed
+ bulk transfers seem to work only with alt=0 ! */
+ dev->alt = 0;
+ if ((alt > 0) && (alt < dev->num_alt)) {
+ em28xx_videodbg("alternate forced to %d\n", dev->alt);
+ dev->alt = alt;
+ goto set_alt;
+ }
+ if (dev->analog_xfer_bulk)
+ goto set_alt;
+
+ /* When image size is bigger than a certain value,
+ the frame size should be increased, otherwise, only
+ green screen will be received.
+ */
+ if (dev->width * 2 * dev->height > 720 * 240 * 2)
+ min_pkt_size *= 2;
+
+ for (i = 0; i < dev->num_alt; i++) {
+ /* stop when the selected alt setting offers enough bandwidth */
+ if (dev->alt_max_pkt_size_isoc[i] >= min_pkt_size) {
+ dev->alt = i;
+ break;
+ /* otherwise make sure that we end up with the maximum bandwidth
+ because the min_pkt_size equation might be wrong...
+ */
+ } else if (dev->alt_max_pkt_size_isoc[i] >
+ dev->alt_max_pkt_size_isoc[dev->alt])
+ dev->alt = i;
+ }
+
+set_alt:
+ /* NOTE: for bulk transfers, we need to call usb_set_interface()
+ * even if the previous settings were the same. Otherwise streaming
+ * fails with all urbs having status = -EOVERFLOW ! */
+ if (dev->analog_xfer_bulk) {
+ dev->max_pkt_size = 512; /* USB 2.0 spec */
+ dev->packet_multiplier = EM28XX_BULK_PACKET_MULTIPLIER;
+ } else { /* isoc */
+ em28xx_videodbg("minimum isoc packet size: %u (alt=%d)\n",
+ min_pkt_size, dev->alt);
+ dev->max_pkt_size =
+ dev->alt_max_pkt_size_isoc[dev->alt];
+ dev->packet_multiplier = EM28XX_NUM_ISOC_PACKETS;
+ }
+ em28xx_videodbg("setting alternate %d with wMaxPacketSize=%u\n",
+ dev->alt, dev->max_pkt_size);
+ errCode = usb_set_interface(dev->udev, dev->ifnum, dev->alt);
+ if (errCode < 0) {
+ em28xx_errdev("cannot change alternate number to %d (error=%i)\n",
+ dev->alt, errCode);
+ return errCode;
+ }
+ return 0;
+}
+