The Windows driver writes the output resolution to registers 0x34 (width / 16)
and 0x35 (height / 16) always.
We don't know yet what these registers are used for.
Signed-off-by: Frank Schäfer <fschaefer.oss@xxxxxxxxxxxxxx>
---
drivers/media/usb/em28xx/em28xx-core.c | 7 +++++++
drivers/media/usb/em28xx/em28xx-reg.h | 6 ++++++
2 Dateien geändert, 13 Zeilen hinzugefügt(+)
diff --git a/drivers/media/usb/em28xx/em28xx-core.c b/drivers/media/usb/em28xx/em28xx-core.c
index 7b9f76b..0ce6b0f 100644
--- a/drivers/media/usb/em28xx/em28xx-core.c
+++ b/drivers/media/usb/em28xx/em28xx-core.c
@@ -766,6 +766,13 @@ static void em28xx_capture_area_set(struct em28xx *dev, u8 hstart, u8 vstart,
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);
+
+ if (dev->is_em25xx) {
+ em28xx_write_reg(dev, 0x34, width >> 4);
+ em28xx_write_reg(dev, 0x35, height >> 4);
+ }
+ /* FIXME: function/meaning of these registers ? */
+ /* FIXME: align width+height to multiples of 4 ?! */
}
static int em28xx_scaler_set(struct em28xx *dev, u16 h, u16 v)
diff --git a/drivers/media/usb/em28xx/em28xx-reg.h b/drivers/media/usb/em28xx/em28xx-reg.h
index d765d59..3ec5528 100644
--- a/drivers/media/usb/em28xx/em28xx-reg.h
+++ b/drivers/media/usb/em28xx/em28xx-reg.h
@@ -167,6 +167,12 @@
#define EM28XX_R34_VBI_START_H 0x34
#define EM28XX_R35_VBI_START_V 0x35
+/* NOTE: the EM276x (and EM25xx, EM277x/8x ?) (camera bridges) use these
+ * registers for a different unknown purpose.
+ * => register 0x34 is set to capture width / 16
+ * => register 0x35 is set to capture height / 16
+ */
+
#define EM28XX_R36_VBI_WIDTH 0x36
#define EM28XX_R37_VBI_HEIGHT 0x37
--
1.7.10.4
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
