[PATCH] ENGR00121057 switch low power mode only support in mc13892 2.0a

Vaidyanathan Ranjani-RA5478 ra5478 at freescale.com
Wed Aug 11 14:17:40 UTC 2010


Hi all,
 I have attached the email that I sent to Bryan Wu on 08/09/2010. I did
verify Bryan's kernel that included the patch mentioned below on 2
BBG2.5 boards (that have Atlas 2.0 parts). I followed the steps
mentioned in the attached email to upgrade the kernel and the 2 BBG2.5
boards booted fine after the kernel upgrade. 

Amit,
  I am sorry, apart from replacing the MX51 and/or the atlas part, I
don't believe there is a way to "unbrick" the broken boards. 

Thanks,
Ranjani



-----Original Message-----
From: Bryan Wu [mailto:bryan.wu at canonical.com] 
Sent: Wednesday, August 11, 2010 8:34 AM
To: Stefan Bader; Amit Kucheria; Vaidyanathan Ranjani-RA5478
Cc: kernel-team at lists.ubuntu.com
Subject: Re: [PATCH] ENGR00121057 switch low power mode only support in
mc13892 2.0a

On 08/11/2010 08:37 PM, Stefan Bader wrote:
> On 08/11/2010 01:56 PM, Amit Kucheria wrote:
>> On 10 Aug 11, Stefan Bader wrote:
>>> On 08/11/2010 12:41 PM, Bryan Wu wrote:
>>>> On 08/10/2010 11:36 PM, Brad Figg wrote:
>>>>> On 08/10/2010 12:07 AM, Bryan Wu wrote:
>>>>>> From: Shen Yong<b00984 at freescale.com>
>>>>>>
>>>>>> switch low power mode will cause problems on previous version of 
>>>>>> mc13892, which may break mc13892 chip.
>>>>>> This is a fix for ENGR00120510.
>>>>>>
>>>>>> BugLink: http://bugs.launchpad.net/bugs/615722
>>>>>>
>>>>>> Signed-off-by: Shen Yong<b00984 at freescale.com>
>>>>>> Signed-off-by: Bryan Wu<bryan.wu at canonical.com>
>>>>>> ---
>>>>>>    arch/arm/mach-mx51/mx51_babbage_pmic_mc13892.c |   30
+++++++++++++++--------
>>>>>>    1 files changed, 19 insertions(+), 11 deletions(-)
>>>>>>
>>>>>> diff --git a/arch/arm/mach-mx51/mx51_babbage_pmic_mc13892.c 
>>>>>> b/arch/arm/mach-mx51/mx51_babbage_pmic_mc13892.c
>>>>>> index e8a03cf..13869d0 100644
>>>>>> --- a/arch/arm/mach-mx51/mx51_babbage_pmic_mc13892.c
>>>>>> +++ b/arch/arm/mach-mx51/mx51_babbage_pmic_mc13892.c
>>>>>> @@ -346,17 +346,25 @@ static int mc13892_regulator_init(struct
mc13892 *mc13892)
>>>>>>    	pmic_write_reg(REG_MODE_1, value, 0xffffff);
>>>>>>
>>>>>>    	/* enable switch audo mode */
>>>>>> -	pmic_read_reg(REG_SW_4,&value, 0xffffff);
>>>>>> -	register_mask = (SWMODE_MASK<<   SW1MODE_LSB) |
(SWMODE_MASK<<   SW2MODE_LSB);
>>>>>> -	value&= ~register_mask;
>>>>>> -	value |= (SWMODE_AUTO<<   SW1MODE_LSB) | (SWMODE_AUTO<<
SW2MODE_LSB);
>>>>>> -	pmic_write_reg(REG_SW_4, value, 0xffffff);
>>>>>> -
>>>>>> -	pmic_read_reg(REG_SW_5,&value, 0xffffff);
>>>>>> -	register_mask = (SWMODE_MASK<<   SW3MODE_LSB) |
(SWMODE_MASK<<   SW4MODE_LSB);
>>>>>> -	value&= ~register_mask;
>>>>>> -	value |= (SWMODE_AUTO<<   SW3MODE_LSB) | (SWMODE_AUTO<<
SW4MODE_LSB);
>>>>>> -	pmic_write_reg(REG_SW_5, value, 0xffffff);
>>>>>> +	pmic_read_reg(REG_IDENTIFICATION,&value, 0xffffff);
>>>>>> +	/* only for mc13892 2.0A */
>>>>>> +	if ((value&   0x0000FFFF) == 0x45d0) {
>>>>>> +		pmic_read_reg(REG_SW_4,&value, 0xffffff);
>>>>>> +		register_mask = (SWMODE_MASK<<   SW1MODE_LSB) |
>>>>>> +		       (SWMODE_MASK<<   SW2MODE_LSB);
>>>>>> +		value&= ~register_mask;
>>>>>> +		value |= (SWMODE_AUTO<<   SW1MODE_LSB) |
>>>>>> +			(SWMODE_AUTO<<   SW2MODE_LSB);
>>>>>> +		pmic_write_reg(REG_SW_4, value, 0xffffff);
>>>>>> +
>>>>>> +		pmic_read_reg(REG_SW_5,&value, 0xffffff);
>>>>>> +		register_mask = (SWMODE_MASK<<   SW3MODE_LSB) |
>>>>>> +			(SWMODE_MASK<<   SW4MODE_LSB);
>>>>>> +		value&= ~register_mask;
>>>>>> +		value |= (SWMODE_AUTO<<   SW3MODE_LSB) |
>>>>>> +			(SWMODE_AUTO<<   SW4MODE_LSB);
>>>>>> +		pmic_write_reg(REG_SW_5, value, 0xffffff);
>>>>>> +	}
>>>>>>
>>>>>>    	/* Enable coin cell charger */
>>>>>>    	value = BITFVAL(CIONCHEN, 1) | BITFVAL(VCOIN,
VCOIN_3_0V);
>>>>>
>>>>> Bryan,
>>>>>
>>>>> Do you have positive test results from testing this patch? We want

>>>>> to make sure this patch fixes the issue that we have been seeing.
>>>>>
>>>>
>>>> Brad,
>>>>
>>>> Yeah, it can be confirmed by Ranjani from Freescale. I copied him 
>>>> in this email thread.
>>>>
>>>> Thanks,
>>>
>>> OK, so this sounds like we can take it. ACK
>>
>> I think Bryan meant we should wait for confirmation from Ranjani. 
>> _She_ will confirm if this fix doesn't brick BB2.5.
>>
>> BTW, is there any chance of unbricking bricked BB2.5 (like mine)?
>>
>> /Amit
>>
>
> Ok, then I hold of with that until this has been confirmed. I have an 
> updated tree ready to push and a source package ready for upload here.
>

Amit and Stefan,

Actually, I sent out this patch after I got the confirmation from
Ranjani via email.

Ranjani,

Could you please confirm it in public here? Sorry for treating you as a
boy/man, -;)

Thanks,
-Bryan

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Subject: RE: Need assistance with 2 bricked Babbage boards
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