[U-Boot-Users] [PATCH] DTT: Issue one-shot command on AD7414 (LM75 code) to read temp

[U-Boot-Users] [PATCH] DTT: Issue one-shot command on AD7414 (LM75 code) to read temp

[Stefan Roese]

On AD7414 the first value upon bootup is not read correctly.
This is most likely because of the 800ms update time of the
temp register in normal update mode. To get current values
each time we issue the "dtt" command including upon powerup
we switch into one-short mode.

This patch fixes the problem on AD7414 equipped boards (Sequoia,
Canyonlands etc), that temp value printed in the bootup log was
incorrect.

Signed-off-by: Stefan Roese <sr@denx.de>
---
 drivers/hwmon/lm75.c |   13 +++++++++++++
 1 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index e29b294..c348517 100644
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c
@@ -47,6 +47,19 @@ int dtt_read(int sensor, int reg)
     int dlen;
     uchar data[2];
 
+#ifdef CONFIG_DTT_AD7414
+    /*
+     * On AD7414 the first value upon bootup is not read correctly.
+     * This is most likely because of the 800ms update time of the
+     * temp register in normal update mode. To get current values
+     * each time we issue the "dtt" command including upon powerup
+     * we switch into one-short mode.
+     *
+     * Issue one-shot mode command
+     */
+    dtt_write(sensor, DTT_CONFIG, 0x64);
+#endif
+
     /*
      * Validate 'reg' param
      */
-- 
1.5.5.1

[U-Boot-Users] [PATCH] DTT: Issue one-shot command on AD7414 (LM75 code) to read temp

[Detlev Zundel]

Hi Stefan,

> To get current values each time we issue the "dtt" command including
> upon powerup we switch into one-short mode.

If we are in "one-short" mode, shouldn't we add 1 before the printout?

Sorry, couldn't resist ;)

Cheers
  Detlev

-- 
error compiling committee.c: too many arguments to function
--
DENX Software Engineering GmbH,      MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich,  Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-40 Fax: (+49)-8142-66989-80 Email: dzu at denx.de

[U-Boot-Users] [PATCH] DTT: Issue one-shot command on AD7414 (LM75 code) to read temp

[Stefan Roese]

On Monday 19 May 2008, Detlev Zundel wrote:
> > To get current values each time we issue the "dtt" command including
> > upon powerup we switch into one-short mode.
>
> If we are in "one-short" mode, shouldn't we add 1 before the printout?

I had to read your mail twice before noticing my error.

> Sorry, couldn't resist ;)

Nice one. ;)

Best regards,
Stefan

=====================================================================
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80  Email: office at denx.de
=====================================================================

[U-Boot-Users] [PATCH] DTT: Issue one-shot command on AD7414 (LM75 code) to read temp

[Wolfgang Denk]

In message <1210928766-31604-1-git-send-email-sr@denx.de> you wrote:
> On AD7414 the first value upon bootup is not read correctly.
> This is most likely because of the 800ms update time of the
> temp register in normal update mode. To get current values
> each time we issue the "dtt" command including upon powerup
> we switch into one-short mode.
> 
> This patch fixes the problem on AD7414 equipped boards (Sequoia,
> Canyonlands etc), that temp value printed in the bootup log was
> incorrect.
> 
> Signed-off-by: Stefan Roese <sr@denx.de>
> ---
>  drivers/hwmon/lm75.c |   13 +++++++++++++
>  1 files changed, 13 insertions(+), 0 deletions(-)

Applied, thanks.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Real computer scientists don't comment their  code.  The  identifiers
are so long they can't afford the disk space.