cx18: Lock the aux PLL to the video pixle rate for analog captures

From: Andy Walls <awalls@radix.net>

cx18: Lock the aux PLL to the video pixel rate for analog captures.  The
datasheet for the CX25840 says this is important for MPEG encoding applications.
To ensure the PLL locking was correct, also fixed the aux PLL's multiplier to
be computed based on a precise crystal freq of 4.5 MHz/286 * 455/2 * 8 =
28636363.6363... instead of the imporperly rounded 28636363.

Signed-off-by: Andy Walls <awalls@radix.net>

1 files changed, 70 insertions, 10 deletions

diff --git a/linux/drivers/media/video/cx18/cx18-av-audio.c b/linux/drivers/media/video/cx18/cx18-av-audio.c
index 7245d37ef..0b5583788 100644
--- a/linux/drivers/media/video/cx18/cx18-av-audio.c
+++ b/linux/drivers/media/video/cx18/cx18-av-audio.c
@@ -51,6 +51,16 @@ static int set_audclk_freq(struct cx18 *cx, u32 freq)
 
 			/* SA_MCLK_SEL=1, SA_MCLK_DIV=0x14 */
 			cx18_av_write(cx, 0x127, 0x54);
+
+			/* AUD_COUNT = 0x2fff = 8 samples * 4 * 384 - 1 */
+			cx18_av_write4(cx, 0x12c, 0x11202fff);
+
+			/*
+			 * EN_AV_LOCK = 1
+			 * VID_COUNT = 0x0d2ef8 = 107999.000 * 8 =
+			 *  ((8 samples/32,000) * (13,500,000 * 8) * 4 - 1) * 8
+			 */
+			cx18_av_write4(cx, 0x128, 0xa10d2ef8);
 			break;
 
 		case 44100:
@@ -58,14 +68,24 @@ static int set_audclk_freq(struct cx18 *cx, u32 freq)
 			cx18_av_write4(cx, 0x108, 0x1009040f);
 
 			/* AUX_PLL_FRAC */
-			/* 0x9.7635eb * 28,636,363 / 0x10 = 44100 * 384 */
-			cx18_av_write4(cx, 0x110, 0x00ec6bd6);
+			/* 0x9.7635e7 * 28,636,363.63 / 0x10 = 44100 * 384 */
+			cx18_av_write4(cx, 0x110, 0x00ec6bce);
 
 			/* src3/4/6_ctl */
 			/* 0x1.6d59 = (4 * 15734.26) / 44100 */
 			cx18_av_write4(cx, 0x900, 0x08016d59);
 			cx18_av_write4(cx, 0x904, 0x08016d59);
 			cx18_av_write4(cx, 0x90c, 0x08016d59);
+
+			/* AUD_COUNT = 0x92ff = 49 samples * 2 * 384 - 1 */
+			cx18_av_write4(cx, 0x12c, 0x112092ff);
+
+			/*
+			 * EN_AV_LOCK = 1
+			 * VID_COUNT = 0x1d4bf8 = 239999.000 * 8 =
+			 *  ((49 samples/44,100) * (13,500,000 * 8) * 2 - 1) * 8
+			 */
+			cx18_av_write4(cx, 0x128, 0xa11d4bf8);
 			break;
 
 		case 48000:
@@ -73,14 +93,24 @@ static int set_audclk_freq(struct cx18 *cx, u32 freq)
 			cx18_av_write4(cx, 0x108, 0x100a040f);
 
 			/* AUX_PLL_FRAC */
-			/* 0xa.4c6b728 * 28,636,363 / 0x10 = 48000 * 384 */
-			cx18_av_write4(cx, 0x110, 0x0098d6e5);
+			/* 0xa.4c6b6ea * 28,636,363.63 / 0x10 = 48000 * 384 */
+			cx18_av_write4(cx, 0x110, 0x0098d6dd);
 
 			/* src3/4/6_ctl */
 			/* 0x1.4faa = (4 * 15734.26) / 48000 */
 			cx18_av_write4(cx, 0x900, 0x08014faa);
 			cx18_av_write4(cx, 0x904, 0x08014faa);
 			cx18_av_write4(cx, 0x90c, 0x08014faa);
+
+			/* AUD_COUNT = 0x5fff = 4 samples * 16 * 384 - 1 */
+			cx18_av_write4(cx, 0x12c, 0x11205fff);
+
+			/*
+			 * EN_AV_LOCK = 1
+			 * VID_COUNT = 0x1193f8 = 143999.000 * 8 =
+			 *  ((4 samples/48,000) * (13,500,000 * 8) * 16 - 1) * 8
+			 */
+			cx18_av_write4(cx, 0x128, 0xa11193f8);
 			break;
 		}
 	} else {
@@ -90,8 +120,8 @@ static int set_audclk_freq(struct cx18 *cx, u32 freq)
 			cx18_av_write4(cx, 0x108, 0x1e08040f);
 
 			/* AUX_PLL_FRAC */
-			/* 0x8.9504348 * 28,636,363 / 0x1e = 32000 * 256 */
-			cx18_av_write4(cx, 0x110, 0x012a0869);
+			/* 0x8.9504318 * 28,636,363.63 / 0x1e = 32000 * 256 */
+			cx18_av_write4(cx, 0x110, 0x012a0863);
 
 			/* src1_ctl */
 			/* 0x1.0000 = 32000/32000 */
@@ -105,6 +135,16 @@ static int set_audclk_freq(struct cx18 *cx, u32 freq)
 
 			/* SA_MCLK_SEL=1, SA_MCLK_DIV=0x14 */
 			cx18_av_write(cx, 0x127, 0x54);
+
+			/* AUD_COUNT = 0x1fff = 8 samples * 4 * 256 - 1 */
+			cx18_av_write4(cx, 0x12c, 0x11201fff);
+
+			/*
+			 * EN_AV_LOCK = 1
+			 * VID_COUNT = 0x0d2ef8 = 107999.000 * 8 =
+			 *  ((8 samples/32,000) * (13,500,000 * 8) * 4 - 1) * 8
+			 */
+			cx18_av_write4(cx, 0x128, 0xa10d2ef8);
 			break;
 
 		case 44100:
@@ -112,8 +152,8 @@ static int set_audclk_freq(struct cx18 *cx, u32 freq)
 			cx18_av_write4(cx, 0x108, 0x1809040f);
 
 			/* AUX_PLL_FRAC */
-			/* 0x9.76346B * 28,636,363 / 0x18 = 44100 * 256 */
-			cx18_av_write4(cx, 0x110, 0x00ec6bd6);
+			/* 0x9.7635e74 * 28,636,363.63 / 0x18 = 44100 * 256 */
+			cx18_av_write4(cx, 0x110, 0x00ec6bce);
 
 			/* src1_ctl */
 			/* 0x1.60cd = 44100/32000 */
@@ -124,6 +164,16 @@ static int set_audclk_freq(struct cx18 *cx, u32 freq)
 			cx18_av_write4(cx, 0x900, 0x08017385);
 			cx18_av_write4(cx, 0x904, 0x08017385);
 			cx18_av_write4(cx, 0x90c, 0x08017385);
+
+			/* AUD_COUNT = 0x61ff = 49 samples * 2 * 256 - 1 */
+			cx18_av_write4(cx, 0x12c, 0x112061ff);
+
+			/*
+			 * EN_AV_LOCK = 1
+			 * VID_COUNT = 0x1d4bf8 = 239999.000 * 8 =
+			 *  ((49 samples/44,100) * (13,500,000 * 8) * 2 - 1) * 8
+			 */
+			cx18_av_write4(cx, 0x128, 0xa11d4bf8);
 			break;
 
 		case 48000:
@@ -131,8 +181,8 @@ static int set_audclk_freq(struct cx18 *cx, u32 freq)
 			cx18_av_write4(cx, 0x108, 0x180a040f);
 
 			/* AUX_PLL_FRAC */
-			/* 0xa.4c6b728 * 28,636,363 / 0x18 = 48000 * 256 */
-			cx18_av_write4(cx, 0x110, 0x0098d6e5);
+			/* 0xa.4c6b6ea * 28,636,363.63 / 0x18 = 48000 * 256 */
+			cx18_av_write4(cx, 0x110, 0x0098d6dd);
 
 			/* src1_ctl */
 			/* 0x1.8000 = 48000/32000 */
@@ -143,6 +193,16 @@ static int set_audclk_freq(struct cx18 *cx, u32 freq)
 			cx18_av_write4(cx, 0x900, 0x08015555);
 			cx18_av_write4(cx, 0x904, 0x08015555);
 			cx18_av_write4(cx, 0x90c, 0x08015555);
+
+			/* AUD_COUNT = 0x3fff = 4 samples * 16 * 256 - 1 */
+			cx18_av_write4(cx, 0x12c, 0x11203fff);
+
+			/*
+			 * EN_AV_LOCK = 1
+			 * VID_COUNT = 0x1193f8 = 143999.000 * 8 =
+			 *  ((4 samples/48,000) * (13,500,000 * 8) * 16 - 1) * 8
+			 */
+			cx18_av_write4(cx, 0x128, 0xa11193f8);
 			break;
 		}
 	}