Re: [PATCH v2] OMAP3 : Fix I2C lockup during timeout/error cases

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* Varadarajan, Charu Latha <charu@xxxxxx> [091210 06:27]:
>  
> 
> >-----Original Message-----
> >From: G, Manjunath Kondaiah 
> >Sent: Thursday, December 10, 2009 6:49 PM
> >To: linux-omap@xxxxxxxxxxxxxxx
> >Cc: G, Manjunath Kondaiah; Menon, Nishanth; Sonasath, Moiz; 
> >Krishnamoorthy, Balaji T; Varadarajan, Charu Latha; George, Harith
> >Subject: [PATCH v2] OMAP3 : Fix I2C lockup during timeout/error cases
> >
> >Current OMAP3 I2C driver code does not follow the correct 
> >sequence for soft
> >reset. Due to this, lock up issues are reported during 
> >timeout/error cases.
> >
> >This patch fixes above issue by disabling I2C controller as 
> >per OMAP3430 TRM
> >for soft reset. As per TRM, I2C controller needs to be 
> >disabled as a first
> >step during soft reset.
> >
> >Here is correct soft reset sequence:
> >a. Ensure that the module is disabled
> >(clear the I2Ci.I2C_CON[15] I2C_EN bit to 0).
> >b. Set the I2Ci.I2C_SYSC[1] SRST bit to 1.
> >c. Enable the module by setting I2Ci.I2C_CON[15] I2C_EN bit to 1.
> >d. Check the I2Ci.I2C_SYSS[0] RDONE bit until it is set to 1 to
> >indicate the software reset is complete.
> >
> >v1 : Initital version
> >v2 : Removed delay since time taken for disabling I2C 
> >controller is zero
> >     jiffies
> >
> >Tested on Zoom2 and Zoom3 
> >
> >Signed-off-by: Manjunatha GK <manjugk@xxxxxx>
> >Signed-off-by: George, Harith<harith@xxxxxx>
> 
> Tested on 3430SDP too.
> Acked-by: Charulatha V <charu@xxxxxx>

This should be sent via the i2c list and to Ben Books.

Regards,

Tony
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