[U-Boot] [beagleboard] TI:OMAP: [PATCH 3/4] Support 720Mhz configuration for OMAP35xx

Khasim Syed Mohammed khasim at beagleboard.org
Sun Jan 10 18:21:53 CET 2010


On Sun, Jan 10, 2010 at 9:14 PM, Nishanth Menon
<menon.nishanth at gmail.com> wrote:
> Khasim Syed Mohammed said the following on 01/09/2010 09:02 PM:
>>
>> On Sat, Jan 9, 2010 at 8:27 PM, Nishanth Menon <menon.nishanth at gmail.com>
>> wrote:
>>>
>>> Khasim Syed Mohammed said the following on 01/08/2010 09:21 PM:
>>>>
>>>> On Sat, Jan 9, 2010 at 1:22 AM, Nishanth Menon
>>>> <menon.nishanth at gmail.com>
>>>> wrote:
>>>>
>>>>> On Fri, Jan 8, 2010 at 9:40 AM, Khasim Syed Mohammed
>>>>> <khasim at beagleboard.org> wrote:
>>>>>
>>>>>> From bba669562fa208d12f4c7cd8188446e8576cd6ee Mon Sep 17 00:00:00 2001
>>>>>> From: Syed Mohammed Khasim <khasim at ti.com>
>>>>>> Date: Fri, 8 Jan 2010 20:34:37 +0530
>>>>>> Subject: [PATCH] Support 720Mhz configuration for OMAP35xx
>>>>>>
> [...]
>
>>>>>> diff --git a/drivers/power/twl4030.c b/drivers/power/twl4030.c
>>>>>> index eb066cb..d68e515 100644
>>>>>> --- a/drivers/power/twl4030.c
>>>>>> +++ b/drivers/power/twl4030.c
>>>>>> @@ -59,16 +59,9 @@ void twl4030_power_reset_init(void)
>>>>>>      }
>>>>>>  }
>>>>>>
>>>>>> -
>>>>>>  /*
>>>>>>  * Power Init
>>>>>>  */
>>>>>> -#define DEV_GRP_P1             0x20
>>>>>> -#define VAUX3_VSEL_28          0x03
>>>>>> -#define DEV_GRP_ALL            0xE0
>>>>>> -#define VPLL2_VSEL_18          0x05
>>>>>> -#define VDAC_VSEL_18           0x03
>>>>>> -
>>>>>>  void twl4030_power_init(void)
>>>>>>  {
>>>>>>      unsigned char byte;
>>>>>> @@ -98,8 +91,6 @@ void twl4030_power_init(void)
>>>>>>                           TWL4030_PM_RECEIVER_VDAC_DEDICATED);
>>>>>>  }
>>>>>>
>>>>>> -#define VMMC1_VSEL_30          0x02
>>>>>> -
>>>>>>  void twl4030_power_mmc_init(void)
>>>>>>  {
>>>>>>      unsigned char byte;
>>>>>> @@ -113,3 +104,18 @@ void twl4030_power_mmc_init(void)
>>>>>>      twl4030_i2c_write_u8(TWL4030_CHIP_PM_RECEIVER, byte,
>>>>>>                           TWL4030_PM_RECEIVER_VMMC1_DEDICATED);
>>>>>>  }
>>>>>> +
>>>>>> +/*
>>>>>> + * Generic function to select Device Group and Voltage
>>>>>> + */
>>>>>> +void twl4030_pmrecv_vsel_cfg(u8 vsel_reg, u8 vsel_val,
>>>>>> +                               u8 dev_grp, u8 dev_grp_sel)
>>>>>> +{
>>>>>> +       /* Select the Device Group */
>>>>>> +       twl4030_i2c_write_u8(TWL4030_CHIP_PM_RECEIVER, dev_grp_sel,
>>>>>> +                               dev_grp);
>>>>>> +
>>>>>> +       /* Select the Voltage */
>>>>>> +       twl4030_i2c_write_u8(TWL4030_CHIP_PM_RECEIVER, vsel_val,
>>>>>> +                               vsel_reg);
>>>>>> +}
>>>>>>
>>>>> Assumption that i2c operations work 100% successfully! is'nt serial
>>>>> bus subject to noise? and cant' i2c ops fail?
>>>>>
>>>> May be,  such cases will be treated as system fail. Should be handled
>>>> separately for "broken platforms".
>>>>
>>>> In beagleboard and EVMs atleast in last 4 revs we have never
>>>> encountered such problems.
>>>>
>>>>
>>> I mean never seen an i2c read/write failure? I have seen at least a
>>> couple
>>> unfortunately when one of the SDP3430's had some one solder a wrong pull
>>> up
>>> resistor and another where a pull up resistor was torn off by accident.
>>>
>>> these are broken platforms ofcourse :).
>>
>> Yeah,
>>
>>> sigh, seeing that the rest of the
>>> file is messed up in this regards, I leave it for the community to
>>> further
>>> comment on this.
>>>
> [...]
>
>>>>>> +#define VAUX3_VSEL_28          0x03
>>>>>> +#define VPLL2_VSEL_18          0x05
>>>>>> +#define VDAC_VSEL_18           0x03
>>>>>> +#define VMMC1_VSEL_30          0x02
>>>>>> +
>>
>> Did you mean these lines ? When I apply the patch I don't see these
>> kind of lines, they are properly arranged in TABs. I have also checked
>> every patch with checkpatch.pl (from Linux). There are no such
>> alignment issues.
>
> no, I meant usage of twl4030_i2c_write_u8() without error check throughout
> the file.
>
Yeah, cleaning up the entire file might have to be a separate effort.
Nothing related to this patch.

I am wondering what one would do if I2C fails, an error message ???
Any way it means hardware is broken. Which will go through debugging
any way.

Regards,
Khasim


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