[U-Boot] [PATCH v2 01/50] dm: clk: Add support for decoding clocks from the device tree

[Simon Glass]

Hi Masahiro,

On 18 January 2016 at 21:29, Masahiro Yamada
<yamada.masahiro at socionext.com> wrote:
> Hi Simon,
>
>
> 2016-01-19 11:27 GMT+09:00 Simon Glass <sjg at chromium.org>:
>> Add a method which can locate a clock for a device, given its index. This
>> uses the normal device tree bindings to return the clock device and the
>> first argument which is normally used as a peripheral ID in U-Boot.
>>
>> Signed-off-by: Simon Glass <sjg at chromium.org>
>> ---
>>
>> Changes in v2:
>> - Make the peripheral ID a return value
>> - Add an assert for clk_devp
>> - Make the function dependent on OF_CONTROL
>>
>>  drivers/clk/clk-uclass.c | 28 ++++++++++++++++++++++++++++
>>  include/clk.h            | 14 ++++++++++++++
>>  2 files changed, 42 insertions(+)
>>
>> diff --git a/drivers/clk/clk-uclass.c b/drivers/clk/clk-uclass.c
>> index 8078b0f..f80beaf 100644
>> --- a/drivers/clk/clk-uclass.c
>> +++ b/drivers/clk/clk-uclass.c
>> @@ -12,6 +12,8 @@
>>  #include <dm/lists.h>
>>  #include <dm/root.h>
>>
>> +DECLARE_GLOBAL_DATA_PTR;
>> +
>>  ulong clk_get_rate(struct udevice *dev)
>>  {
>>         struct clk_ops *ops = clk_get_ops(dev);
>> @@ -62,6 +64,32 @@ int clk_get_id(struct udevice *dev, int args_count, uint32_t *args)
>>         return ops->get_id(dev, args_count, args);
>>  }
>>
>> +#ifdef CONFIG_OF_CONTROL
>
> Isn't this #if CONFIG_IS_ENABLED(OF_CONTROL)?
>
> SPL is controlled by CONFIG_SPL_OF_CONTROL.
>

OK

>
>
>> +int clk_get_by_index(struct udevice *dev, int index, struct udevice **clk_devp)
>> +{
>> +       struct fdtdec_phandle_args args;
>> +       int ret;
>> +
>> +       assert(*clk_devp);
>> +       ret = fdtdec_parse_phandle_with_args(gd->fdt_blob, dev->of_offset,
>> +                                            "clocks", "#clock-cells", 0, index,
>> +                                            &args);
>> +       if (ret) {
>> +               debug("%s: fdtdec_parse_phandle_with_args failed: err=%d\n",
>> +                     __func__, ret);
>> +               return ret;
>> +       }
>> +
>> +       ret = uclass_get_device_by_of_offset(UCLASS_CLK, args.node, clk_devp);
>> +       if (ret) {
>> +               debug("%s: uclass_get_device_by_of_offset failed: err=%d\n",
>> +                     __func__, ret);
>> +               return ret;
>> +       }
>> +       return args.args_count > 0 ? args.args[0] : 0;
>> +}
>> +#endif
>> +
>>  UCLASS_DRIVER(clk) = {
>>         .id             = UCLASS_CLK,
>>         .name           = "clk",
>> diff --git a/include/clk.h b/include/clk.h
>> index ce2db41..0af2824 100644
>> --- a/include/clk.h
>> +++ b/include/clk.h
>> @@ -150,4 +150,18 @@ static inline int fdt_clk_get(const void *fdt, int nodeoffset, int index,
>>  }
>>  #endif
>>
>> +/**
>> + * clk_get_by_index() - look up a clock referenced by a device
>> + *
>> + * Parse a device's 'clocks' list, returning information on the indexed clock,
>> + * ensuring that it is activated.
>> + *
>> + * @dev:       Device containing the clock reference
>> + * @index:     Clock index to return (0 = first)
>> + * @clk_devp:  Returns clock device
>> + * @return:    Peripheral ID for the device to control. This is the first
>> + *             argument after the clock node phandle. If there is no arguemnt,
>> + *             returns 0. Return -ve error code on any error
>> + */
>> +int clk_get_by_index(struct udevice *dev, int index, struct udevice **clk_devp);
>>  #endif /* _CLK_H_ */
>
>
> I want #ifdef in the header too, like mine
> http://patchwork.ozlabs.org/patch/566812/

I am not keen on that idea since it clutters up header files and we'll
get a link error anyway if something is missing. Anyway, I've added
it.

Regards,
Simon