V4L/DVB (10088): video: sh_mobile_ceu cleanups and comments
This patch cleans up the sh_mobile_ceu driver and adds comments and
constants to clarify the magic sequence in sh_mobile_ceu_capture().
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/sh_mobile_ceu_camera.c b/drivers/media/video/sh_mobile_ceu_camera.c
index 7d1a844..79eda0f 100644
--- a/drivers/media/video/sh_mobile_ceu_camera.c
+++ b/drivers/media/video/sh_mobile_ceu_camera.c
@@ -101,13 +101,12 @@
};
static void ceu_write(struct sh_mobile_ceu_dev *priv,
- unsigned long reg_offs, unsigned long data)
+ unsigned long reg_offs, u32 data)
{
iowrite32(data, priv->base + reg_offs);
}
-static unsigned long ceu_read(struct sh_mobile_ceu_dev *priv,
- unsigned long reg_offs)
+static u32 ceu_read(struct sh_mobile_ceu_dev *priv, unsigned long reg_offs)
{
return ioread32(priv->base + reg_offs);
}
@@ -155,18 +154,26 @@
buf->vb.state = VIDEOBUF_NEEDS_INIT;
}
+#define CEU_CETCR_MAGIC 0x0317f313 /* acknowledge magical interrupt sources */
+#define CEU_CETCR_IGRW (1 << 4) /* prohibited register access interrupt bit */
+#define CEU_CEIER_CPEIE (1 << 0) /* one-frame capture end interrupt */
+#define CEU_CAPCR_CTNCP (1 << 16) /* continuous capture mode (if set) */
+
+
static void sh_mobile_ceu_capture(struct sh_mobile_ceu_dev *pcdev)
{
struct soc_camera_device *icd = pcdev->icd;
- unsigned long phys_addr;
+ dma_addr_t phys_addr;
- ceu_write(pcdev, CEIER, ceu_read(pcdev, CEIER) & ~1);
- ceu_write(pcdev, CETCR, ~ceu_read(pcdev, CETCR) & 0x0317f313);
- ceu_write(pcdev, CEIER, ceu_read(pcdev, CEIER) | 1);
-
- ceu_write(pcdev, CAPCR, ceu_read(pcdev, CAPCR) & ~0x10000);
-
- ceu_write(pcdev, CETCR, 0x0317f313 ^ 0x10);
+ /* The hardware is _very_ picky about this sequence. Especially
+ * the CEU_CETCR_MAGIC value. It seems like we need to acknowledge
+ * several not-so-well documented interrupt sources in CETCR.
+ */
+ ceu_write(pcdev, CEIER, ceu_read(pcdev, CEIER) & ~CEU_CEIER_CPEIE);
+ ceu_write(pcdev, CETCR, ~ceu_read(pcdev, CETCR) & CEU_CETCR_MAGIC);
+ ceu_write(pcdev, CEIER, ceu_read(pcdev, CEIER) | CEU_CEIER_CPEIE);
+ ceu_write(pcdev, CAPCR, ceu_read(pcdev, CAPCR) & ~CEU_CAPCR_CTNCP);
+ ceu_write(pcdev, CETCR, CEU_CETCR_MAGIC ^ CEU_CETCR_IGRW);
if (!pcdev->active)
return;
@@ -179,7 +186,7 @@
case V4L2_PIX_FMT_NV21:
case V4L2_PIX_FMT_NV16:
case V4L2_PIX_FMT_NV61:
- phys_addr += (icd->width * icd->height);
+ phys_addr += icd->width * icd->height;
ceu_write(pcdev, CDACR, phys_addr);
}
@@ -431,13 +438,13 @@
}
}
- if ((icd->current_fmt->fourcc == V4L2_PIX_FMT_NV21) ||
- (icd->current_fmt->fourcc == V4L2_PIX_FMT_NV61))
+ if (icd->current_fmt->fourcc == V4L2_PIX_FMT_NV21 ||
+ icd->current_fmt->fourcc == V4L2_PIX_FMT_NV61)
value ^= 0x00000100; /* swap U, V to change from NV1x->NVx1 */
- value |= (common_flags & SOCAM_VSYNC_ACTIVE_LOW) ? (1 << 1) : 0;
- value |= (common_flags & SOCAM_HSYNC_ACTIVE_LOW) ? (1 << 0) : 0;
- value |= (buswidth == 16) ? (1 << 12) : 0;
+ value |= common_flags & SOCAM_VSYNC_ACTIVE_LOW ? 1 << 1 : 0;
+ value |= common_flags & SOCAM_HSYNC_ACTIVE_LOW ? 1 << 0 : 0;
+ value |= buswidth == 16 ? 1 << 12 : 0;
ceu_write(pcdev, CAMCR, value);
ceu_write(pcdev, CAPCR, 0x00300000);
@@ -447,13 +454,13 @@
if (yuv_mode) {
width = icd->width * 2;
- width = (buswidth == 16) ? width / 2 : width;
+ width = buswidth == 16 ? width / 2 : width;
cfszr_width = cdwdr_width = icd->width;
} else {
width = icd->width * ((icd->current_fmt->depth + 7) >> 3);
- width = (buswidth == 16) ? width / 2 : width;
- cfszr_width = (buswidth == 8) ? width / 2 : width;
- cdwdr_width = (buswidth == 16) ? width * 2 : width;
+ width = buswidth == 16 ? width / 2 : width;
+ cfszr_width = buswidth == 8 ? width / 2 : width;
+ cdwdr_width = buswidth == 16 ? width * 2 : width;
}
ceu_write(pcdev, CAMOR, 0);