This is a note to let you know that I've just added the patch titled

    ASoC: sgtl5000: add delay before first I2C access

to the 3.18-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     asoc-sgtl5000-add-delay-before-first-i2c-access.patch
and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 58cc9c9a175885bbf6bae3acf18233d0a8229a84 Mon Sep 17 00:00:00 2001
From: Eric Nelson <[email protected]>
Date: Fri, 30 Jan 2015 14:07:55 -0700
Subject: ASoC: sgtl5000: add delay before first I2C access

From: Eric Nelson <[email protected]>

commit 58cc9c9a175885bbf6bae3acf18233d0a8229a84 upstream.

To quote from section 1.3.1 of the data sheet:
        The SGTL5000 has an internal reset that is deasserted
        8 SYS_MCLK cycles after all power rails have been brought
        up. After this time, communication can start

        ...
        1.0us represents 8 SYS_MCLK cycles at the minimum 8.0 MHz SYS_MCLK.

Signed-off-by: Eric Nelson <[email protected]>
Reviewed-by: Fabio Estevam <[email protected]>
Signed-off-by: Mark Brown <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 sound/soc/codecs/sgtl5000.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/sound/soc/codecs/sgtl5000.c
+++ b/sound/soc/codecs/sgtl5000.c
@@ -1452,6 +1452,9 @@ static int sgtl5000_i2c_probe(struct i2c
        if (ret)
                return ret;
 
+       /* Need 8 clocks before I2C accesses */
+       udelay(1);
+
        /* read chip information */
        ret = regmap_read(sgtl5000->regmap, SGTL5000_CHIP_ID, &reg);
        if (ret)


Patches currently in stable-queue which might be from 
[email protected] are

queue-3.18/asoc-sgtl5000-add-delay-before-first-i2c-access.patch
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