From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Schocher Date: Thu, 19 Mar 2009 08:47:28 +0100 Subject: [U-Boot] [PATCH] Coldfire: I2C: Update I2CFDR frequency divider 0x0E value from 192 to 204 In-Reply-To: <49C12A4F.5090607@RuggedCom.com> References: <49C12A4F.5090607@RuggedCom.com> Message-ID: <49C1F890.9060400@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hello Richard, Richard Retanubun wrote: > From 9a7a9dfb1ed367b275bc19f7c40c98b63de75fb2 Mon Sep 17 00:00:00 2001 > From: Richard Retanubun > Date: Wed, 18 Mar 2009 12:52:35 -0400 > Subject: [PATCH] Update I2CFDR frequency divider 0x0E value from 192 to 204. > > This patch changes the divider factor of 14 for I2CFDR. > Through empirical experiments on a M5271EVB with a 25MHz osc, > multiplied to 75MHz system frequency, the divider 0x0E that is > supposed to be div-by-192, results in i2c clock of ~376 KHz > (which is ~div-by-204). Using the alternate divider for div-by-192 > (49) results in an i2c clock of ~390 KHz, a better clock approximation. > > Signed-off-by: Richard Retanubun > --- > drivers/i2c/fsl_i2c.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/i2c/fsl_i2c.c b/drivers/i2c/fsl_i2c.c > index ce646fd..c61bf84 100644 > --- a/drivers/i2c/fsl_i2c.c > +++ b/drivers/i2c/fsl_i2c.c > @@ -113,8 +113,8 @@ static const struct { > {56, 41}, {64, 42}, {68, 7}, {72, 43}, > {80, 8}, {80, 44}, {88, 9}, {96, 41}, > {104, 10}, {112, 42}, {128, 11}, {128, 43}, > - {144, 12}, {160, 13}, {160, 48}, {192, 14}, > - {192, 49}, {224, 50}, {240, 15}, {256, 51}, > + {144, 12}, {160, 13}, {160, 48}, {192, 49}, > + {204, 14}, {224, 50}, {240, 15}, {256, 51}, > {288, 16}, {320, 17}, {320, 52}, {384, 18}, > {384, 53}, {448, 54}, {480, 19}, {512, 55}, > {576, 20}, {640, 21}, {640, 56}, {768, 22}, > Because I think this will go through the coldfire tree, you have my: Acked-by: Heiko Schocher bye Heiko -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany