On 01/09/2015 06:50 AM, Philipp Zabel wrote:
> Hi Stephen,
>
> Am Donnerstag, den 08.01.2015, 13:32 -0800 schrieb Stephen Boyd:
> [...]
>> Why not do this in the core? As far as I can tell other drivers could
>> run into the same problem, no? Does this work?
>>
>> -----8<-------
>>
>> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
>> index f4963b7d4e17..3278645f4729 100644
>> --- a/drivers/clk/clk.c
>> +++ b/drivers/clk/clk.c
>> @@ -1677,16 +1677,18 @@ int clk_set_parent(struct clk *clk, struct clk
>> *parent)
>> if (!clk)
>> return 0;
>>
>> - /* verify ops for for multi-parent clks */
>> - if ((clk->num_parents > 1) && (!clk->ops->set_parent))
>> - return -ENOSYS;
>> -
>> /* prevent racing with updates to the clock topology */
>> clk_prepare_lock();
>>
>> if (clk->parent == parent)
>> goto out;
>>
>> + /* verify ops for for multi-parent clks */
>> + if ((clk->num_parents > 1) && (!clk->ops->set_parent)) {
>> + ret = -ENOSYS;
>> + goto out;
>> + }
>> +
>> /* check that we are allowed to re-parent if the clock is in use */
>> if ((clk->flags & CLK_SET_PARENT_GATE) && clk->prepare_count) {
>> ret = -EBUSY;
> "[PATCH] clk: make set_parent succeed for any clock if the parent to be
> set is the same as the current parent" ?
>
> It works, but it also changes the API, as it makes
> clk_set_parent(some_non_mux, its_current_parent)
> succeed instead of return -ENOSYS.
I would think a non_mux clk would have clk->num_parents == 1, so I don't
see how it would return -ENOSYS here. What you mention should succeed
today. Otherwise we have a bug.
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
