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From: s.hauer@pengutronix.de (Sascha Hauer)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] i2c i.MX: Fix divider table
Date: Thu,  5 Jul 2012 15:10:26 +0200	[thread overview]
Message-ID: <1341493826-13861-1-git-send-email-s.hauer@pengutronix.de> (raw)

Measurements on i.MX1 and i.MX53 have shown that the divider values
in the datasheets are wrong. the values from first, third and fourth
column were all measured to be 8 higher than in the datasheet. It
should be safe to assume that the SoCs between i.MX1 and i.MX53 behave
the same as the i2c unit is unchanged since the i.MX1.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 drivers/i2c/busses/i2c-imx.c |   31 ++++++++++++++++++-------------
 1 file changed, 18 insertions(+), 13 deletions(-)

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 8d6b504..aabbe31 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -98,22 +98,27 @@
  * Document Number: MC9328MXLRM, Rev. 5.1, 06/2007
  *
  * Duplicated divider values removed from list
+ *
+ * These values (mostly) do not match the ones in the datasheet because
+ * measurements have shown that the values are wrong. This was tested
+ * on i.MX1 and i.MX53, so it shoud be safe to assume that the SoCs in
+ * between behave the same.
  */
 
 static u16 __initdata i2c_clk_div[50][2] = {
-	{ 22,	0x20 }, { 24,	0x21 }, { 26,	0x22 }, { 28,	0x23 },
-	{ 30,	0x00 },	{ 32,	0x24 }, { 36,	0x25 }, { 40,	0x26 },
-	{ 42,	0x03 }, { 44,	0x27 },	{ 48,	0x28 }, { 52,	0x05 },
-	{ 56,	0x29 }, { 60,	0x06 }, { 64,	0x2A },	{ 72,	0x2B },
-	{ 80,	0x2C }, { 88,	0x09 }, { 96,	0x2D }, { 104,	0x0A },
-	{ 112,	0x2E }, { 128,	0x2F }, { 144,	0x0C }, { 160,	0x30 },
-	{ 192,	0x31 },	{ 224,	0x32 }, { 240,	0x0F }, { 256,	0x33 },
-	{ 288,	0x10 }, { 320,	0x34 },	{ 384,	0x35 }, { 448,	0x36 },
-	{ 480,	0x13 }, { 512,	0x37 }, { 576,	0x14 },	{ 640,	0x38 },
-	{ 768,	0x39 }, { 896,	0x3A }, { 960,	0x17 }, { 1024,	0x3B },
-	{ 1152,	0x18 }, { 1280,	0x3C }, { 1536,	0x3D }, { 1792,	0x3E },
-	{ 1920,	0x1B },	{ 2048,	0x3F }, { 2304,	0x1C }, { 2560,	0x1D },
-	{ 3072,	0x1E }, { 3840,	0x1F }
+	{ 30,	0x20 }, { 32,	0x21 }, { 34,	0x22 },	{ 36,	0x23 },
+	{ 38,	0x00 },	{ 40,	0x24 },	{ 44,	0x25 },	{ 48,	0x26 },
+	{ 50,	0x03 },	{ 52,	0x27 },	{ 56,	0x28 }, { 60,	0x05 },
+	{ 64,	0x29 }, { 68,	0x06 }, { 72,	0x2A },	{ 80,	0x2B },
+	{ 88,	0x2C }, { 96,	0x09 }, { 104,	0x2D }, { 112,	0x0A },
+	{ 120,	0x2E }, { 136,	0x2F }, { 152,	0x0C },	{ 168,	0x30 },
+	{ 200,	0x31 }, { 232,	0x32 }, { 248,	0x0F },	{ 264,	0x33 },
+	{ 288,	0x10 },	{ 328,	0x34 },	{ 392,	0x35 },	{ 456,	0x36 },
+	{ 480,	0x13 },	{ 520,	0x37 },	{ 576,	0x14 },	{ 648,	0x38 },
+	{ 776,	0x39 },	{ 904,	0x3A },	{ 960,	0x17 },	{ 1032,	0x3B },
+	{ 1152,	0x18 },	{ 1288,	0x3C },	{ 1544,	0x3D },	{ 1800,	0x3E },
+	{ 1920,	0x1B },	{ 2048,	0x3F },	{ 2304,	0x1C },	{ 2560,	0x1D },
+	{ 3072,	0x1E },	{ 3840,	0x1F }
 };
 
 struct imx_i2c_struct {
-- 
1.7.10

             reply	other threads:[~2012-07-05 13:10 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-07-05 13:10 Sascha Hauer [this message]
2012-07-05 14:23 ` [PATCH] i2c i.MX: Fix divider table Baruch Siach
2012-07-05 14:52 ` Richard Zhao
2012-07-05 16:01   ` Sascha Hauer
2012-07-06  0:52     ` Richard Zhao
2012-07-06  6:28       ` Sascha Hauer
2012-07-06 17:41         ` Troy Kisky
2012-07-11  6:01         ` Richard Zhao
2012-07-11 18:38           ` Sascha Hauer
2012-07-11 19:11             ` Troy Kisky
2012-07-11 19:44               ` Sascha Hauer
2012-07-12  0:45             ` Richard Zhao
2012-07-05 18:06 ` Shubhrajyoti Datta
2012-07-05 18:47   ` Sascha Hauer
2012-07-08  9:14     ` Shubhrajyoti Datta

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