resandevinwebb, btw thank you for sharing the information. This is of
personal interest for me as well.

On Tue, Nov 25, 2014 at 5:58 PM, William Hermans <[email protected]> wrote:

> Ah ok my mistake I misread your post initially as I did not read the whole
> thing sorry.
>
> So yes, I would think you would have to write your own kernel module, or
> modify the existing I2C bus utils. Recompile, etc.
>
> On Tue, Nov 25, 2014 at 5:52 PM, William Hermans <[email protected]>
> wrote:
>
>> *>  i2cdetect -l*
>>> *> on Beaglebone Black it will give you:*
>>> *i2c-0   unknown         OMAP I2C adapter                        N/A*
>>> *i2c-1   unknown         OMAP I2C adapter                        N/A*
>>>
>>
>> Ok, so I2C to the PMIC does work. A person on the group got this working
>> from within uboot and posted about it over a month ago.
>>
>> When i asked, "ok great, but how does that translate to this working
>> while under linux?" He / she replied: something to the effect of "I'm
>> unsure".
>>
>> Anyway, the point is it is possible to control the PMIC, or at minimum
>> communicate with it via software + I2C. I am however not a Linux kernel
>> expert / guru, but I *would* assume this would require a kernel level
>> driver to work.
>>
>>
>> On Tue, Nov 25, 2014 at 2:31 PM, <[email protected]> wrote:
>>
>>> Hi liyaoshi,
>>>
>>> So how can I measure the charge percentage left in the battery? Is there
>>> an example that I can use? TPS65217 does not allow us to read the battery
>>> voltage if I am right or at least I cannot find it in datasheet. what
>>> voltage are you talking about?
>>>
>>> I did some progress with controlling PMIC and I can use i2c utilities to
>>> read and write to it. However I have to use -f to force it since kernel is
>>> using the I2C interface. How can I do this cleanly from user space without
>>> forcing it? One way would be to expand the driver to add extra features.
>>> Does anyone know a good example that I can use as starting point? Is there
>>> a better/easier way to do this?
>>> my procedure is as follow:
>>>
>>>  i2cdetect -l
>>> on Beaglebone Black it will give you:
>>>
>>> i2c-0   unknown         OMAP I2C adapter                        N/A
>>>
>>> i2c-1   unknown         OMAP I2C adapter                        N/A
>>>
>>>
>>> For reading status register of TPS65217. device is at 0x25 and status
>>> register is 0x0a on I2C0
>>>
>>> i2cget [-f] [-y] i2cbus chip-address [data-address [mode]]
>>>
>>>
>>> sudo i2cdet -f 0 0c24 0x0a
>>>
>>> WARNING! This program can confuse your I2C bus, cause data loss and
>>> worse!
>>>
>>> I will read from device file /dev/i2c-0, chip address 0x24, data address
>>>
>>> 0x0a, using read byte data.
>>>
>>> Continue?
>>> [Y/n]
>>> 0x88
>>>
>>>
>>> To set battery charging voltage to 4.2V
>>>
>>> i2cset [-f] [-y] [-m mask] [-r] i2cbus chip-address data-address [value]
>>> ... [mode]
>>> sudo i2cset -f -m 0x30 0 0x24 0x05 0x20
>>>
>>> WARNING! This program can confuse your I2C bus, cause data loss and
>>> worse!
>>>
>>> I will write to device file /dev/i2c-0, chip address 0x24, data address
>>>
>>> 0x05, data 0x20 (masked), mode byte.
>>>
>>> Continue? [Y/n]
>>>
>>> Old value 0x80, write mask 0x30: Will write 0xa0 to register 0x05
>>>
>>> Continue? [Y/n]
>>>
>>>
>>> Thanks a lot
>>>
>>>
>>>
>>> On Monday, November 24, 2014 6:08:45 PM UTC-8, liyaoshi wrote:
>>>>
>>>> As I know , if only 2 wires , you can not access the Li+battery status
>>>> , you can just get voltage value from PMU
>>>>
>>>> There always another 1 wire to get the communication with MCU in
>>>> battery module
>>>>
>>>> 2014-11-25 8:52 GMT+08:00 <[email protected]>:
>>>>
>>>>> Hi All,
>>>>>
>>>>> I connected a rechargeable Li+ battery to my BBB TP5, TP6, TP7, and
>>>>> TP8. I shorted TP5 and TP6 and added a 10uF decoupling capacitor. In
>>>>> addition, I connected TS to GND with a 9K resistor which is 10K || 75K
>>>>> according to the datasheet and the board boots fine from battery.
>>>>> Now my question is that how can I monitor the battery status(how much
>>>>> they are charged) or change the setting of PMIC, TPS65127C from shell. For
>>>>> instance, I would like to set the charging voltage to 4.2 rather than the
>>>>> default 4.1V. Or I would like to turn on/off WLED etc. Is there a tool,
>>>>> like Alsamixer, for this? if not what would be the best approach for
>>>>> controlling PMIC from shell? I posted it here because PMIC uses I2C
>>>>> interface to talk to AM335x.
>>>>>
>>>>>
>>>>> <https://lh4.googleusercontent.com/-E-wdJPfnG5U/VHPNaDDU9WI/AAAAAAAAAAo/tEjegAyAzAM/s1600/bbb-batt-srm.jpg>
>>>>>
>>>>>
>>>>> <https://lh3.googleusercontent.com/-d7FQ9BVS6J4/VHPNtiSxI4I/AAAAAAAAAAw/3_g2aL5Q2K4/s1600/bbb-batt1.jpg>
>>>>>
>>>>> Thanks for your time and consideration.
>>>>>
>>>>>  --
>>>>> For more options, visit http://beagleboard.org/discuss
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>>>>>
>>>>
>>>>  --
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>>
>>
>

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