[U-Boot] [PATCH 0/3] Bring in new I2C framework

[Heiko Schocher <hs@denx.de>]

Hello Simon,

On 30.10.2012 18:22, Simon Glass wrote:
> Hi,
>
> On Tue, Oct 30, 2012 at 9:50 AM, Stephen Warren<swarren@wwwdotorg.org>  wrote:
>> On 10/29/2012 11:57 PM, Heiko Schocher wrote:
>>> Hello Stephen,
>>>
>>> On 29.10.2012 16:34, Stephen Warren wrote:
>> ...
>>>> If there are e.g. 4 I2C controllers in an SoC, the driver needs to know
>>>> which one is in use. Passing that information directly to the driver
>>>> functions is much simple than requiring the SoC I2C driver to go grovel
>>>> in some I2C core global variables to find out the same information.
>>>
>>> Ah, do you mean we should change the i2c adapter struct from:
>>>
>>> struct i2c_adapter {
>>>         void            (*init)(int speed, int slaveaddr);
>>>         int             (*probe)(uint8_t chip);
>>>         int             (*read)(uint8_t chip, uint addr, int alen,
>>>                                 uint8_t *buffer, int len);
>>>         int             (*write)(uint8_t chip, uint addr, int alen,
>>>                                 uint8_t *buffer, int len);
>>>         uint            (*set_bus_speed)(uint speed);
>>> [...]
>>>
>>> to
>>>
>>> struct i2c_adapter {
>>>         void            (*init)(struct i2c_adapter *adap, int speed, int
>>> slaveaddr);
>>>         int             (*probe)(struct i2c_adapter *adap, uint8_t chip);
>>>         int             (*read)(struct i2c_adapter *adap, uint8_t chip,
>>> uint addr, int alen,
>>>                                 uint8_t *buffer, int len);
>>>         int             (*write)(struct i2c_adapter *adap, uint8_t chip,
>>> uint addr, int alen,
>>>                                 uint8_t *buffer, int len);
>>>         uint            (*set_bus_speed)(struct i2c_adapter *adap, uint
>>> speed);
>>> [...]
>>> ?
>>>
>>> We can do this. Simon suggested this too ...
>>
>> Yes, exactly. (the functions will need some way to get information out
>> of the struct i2c_adapter; I assume there's some kind of driver_private
>> field in there too).
>
> Yes.
>
> I will post a few patches to move Tegra over to the new framework as
> it is, so that people can see the impact. Given that every driver has
> to change, it would be my preference to set the i2c API once. But I
> suppose within a short while everything will move to the device model,
> so perhaps the job of this series is just to move things in the right
> direction?

Yes, but not only, I think the i2c framework needs an update.

bye,
heiko
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