[U-Boot] [PATCH 04/10] power: Explicitly select pmic device's bus

Heiko Schocher
2014-03-31T05:17:37Z

Hello Simon, Lukasz,

Am 30.03.2014 01:17, schrieb Simon Glass:
> Hi Lukasz,
>
> On 27 March 2014 11:33, Lukasz Majewski<l.majewski@samsung.com> wrote:
>
>> Hi Simon, Heiko
>>
>>> From: Aaron Durbin<adurbin@chromium.org>
>>>
>>> The current pmic i2c code assumes the current i2c bus is
>>> the same as the pmic device's bus. There is nothing ensuring
>>> that to be true. Therefore, select the proper bus before performing
>>> a transaction.
>>>
>>> Signed-off-by: Aaron Durbin<adurbin@chromium.org>
>>> Signed-off-by: Simon Glass<sjg@chromium.org>
>>> Reviewed-by: Simon Glass<sjg@chromium.org>
>>> ---
>>>
>>> drivers/power/power_i2c.c | 4 ++++
>>> 1 file changed, 4 insertions(+)
>>>
>>> diff --git a/drivers/power/power_i2c.c b/drivers/power/power_i2c.c
>>> index ac76870..594cd11 100644
>>> --- a/drivers/power/power_i2c.c
>>> +++ b/drivers/power/power_i2c.c
>>> @@ -23,6 +23,8 @@ int pmic_reg_write(struct pmic *p, u32 reg, u32 val)
>>> if (check_reg(p, reg))
>>> return -1;
>>>
>>> + I2C_SET_BUS(p->bus);
>>> +
>>
>> Hadn't we had a discussion about this explicit setting of I2C some time
>> ago? I thought that this problem was solved within the I2C rework.
>>
>> Also I might be wrong, so please correct me if I'm wrong. Isn't the
>> I2C_SET_BUS() macro regarded as a obsolete after the I2C rework?
>>
>
> Agreed that would be ideal, but we would have to pass the bus number of the
> i2c_read/write() functions. I don't believe the i2c code has got that far
> yet.

Yes, thats the plan, but first, all i2c driver must be converted to
the new framework. After that we could start with such an approach
(or device model is ready and we can switch to it ...)

> Unfortunately it doesn't work without this patch.

Yes ...

If we have all i2c driver running with the new framework, we can get
rid of I2C_SET_BUS defines, and simply use i2c_set_bus_num() which
is a simple cleanup patch.

bye,
Heiko
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