On Thu, Mar 27, 2014 at 04:29:37PM +0530, Viresh Kumar wrote:
On 27 March 2014 16:18, Gautham R Shenoy ego@linux.vnet.ibm.com wrote:
So after this patch, driver_data is only going to be used by drivers which want an "unsigned int" value to be saved along with the frequency in the frequency_table and for those who want to overload its interpretation to indicate BOOST.
From the core's stand point, it is useful only for determining whether a frequency is BOOST frequency or not.
Yes.
So, wouldn't it be logical to allow drivers maintain their own driver data since the core is anyway not interested in it, and change this .driver_data to "flags" or some such which can indicate boost ?
We can add another field .flags in case Rafael doesn't accept the other proposal I sent for fixing BOOST issue.
Even with that patch, the .driver_data won't be opaque. And that's not good. Because, while some driver might not be explicitly setting the value of .driver_data to 0xABABABAB, it might want to store the value obtained at runtime into this field. And it could so happen that at runtime this value is 0xABABABAB.
But the point behind keeping .driver_data field here was: many drivers have some information attached to each frequency and they are closely bound to each other. And so it made more sense to keep them together. This is still used by many drivers and I wouldn't like them to maintain separate arrays for keeping this information. They are so much bound to the frequencies at the same index, that keeping them separately wouldn't be a good idea.
I understand this part. However there might be more data than an "unsigned int" that the drivers would like to be bound at the same index. Voltage information, for instance.
-- Thanks and Regards gautham.