Re: Forcing wi-fi chipset to sleep from bcm4329 driver

["Franky Lin" <frankyl@broadcom.com>]

On 08/16/2012 04:08 AM, Dani Camps wrote:
> Dear all,
>
> I would like to be able to control the power state (i.e. sleep/awake) of a broadcom wi-fi chipset controlled by the bcm4329 driver. My understanding of sleep/awake is the following: wi-fi chipsets support power saving protocols that allow them to enter into a low power state in order to save energy, this is what I understand as the sleep state. On the other hand when the chipset is fully powered and can directly receive data from the AP, this is what I understand as the chipset being in awake state.
>
> Now, in the bcm4329 driver I have seen that the power mode of the wi-fi chipset can be configured with the parameters PM_MAX, PM_FAST and PM_OFF. My understanding though is that these are simply parameters to configure an internal power saving algorithm that is implemented in the chipset itself, e.g. if I configure PM_MAX it does not mean that the chipset will enter sleep mode immediately, but it will only do it according to a certain particular algorithm that I cannot conttol. Therefore, my question is whether it is possible to control the power state (sleep/awake) of the wi-fi chipset directly from within bcm4329.
>

Hi Dani,

By bcm4329 I assume you are referring to the host driver could be found 
in Android's tree.

Anyway, bcm4329 and brcmfmac don't provide the capability to fully 
control the chip. As a fullmac mechanism the chip firmware handles the 
MAC stuff and knows the best timing of power management. Current PM 
implementation does quiet a good job. You can adjust some settings to 
further reduce the wake up frequency of the chip. But if you want 
anything better than that I am afraid cutting off the power supply is 
the only option.

Regards,
Franky