On Mon, Jun 18, 2012 at 23:01:45, Stephen Warren wrote: >On 06/18/2012 02:03 AM, Laxman Dewangan wrote: >> Rakesh Kumar wrote at Monday, June 18, 2012 1:11 PM: >> > Stephen Warren wrote: >> >> Now if this means adding a child node under the SDIO controller to >> >> represent the attached device, and storing any settings required >> >> by that device in that child node, that's probably a reasonable >> >> basic approach. >> >> >> >> BTW, which GPIO is the power GPIO; is it WF_EN on the schematic? >> >> That seems reasonable to represent as a GPIO rather than a >> >> regulator since it connects directly into the WiFi device as a >> >> GPIO, and its use within the WiFi device can indeed be governed >> >> purely internally to the WiFi driver/HW. However, if this is some >> >> GPIO that controls the power to e.g. VBAT3V3_IN_WF, VDDIO_WF, or >> >> other power supply to the WiFi card, then it'd be better >> >> represented as a regulator, since the control point is outside the >> >> WiFi device. >> > >> > Tegra uses two GPIO (WF_EN and WF_RST) to power on and reset >> > bcm4329 card. In case of bcm4329, these two lines are shorted. >> > Tegra does not control VBAT3V3_IN_WF, VDDIO_WF, or other power >> > supply to the WiFi card based on these GPIO. Uses of these GPIO are >> > internal to WiFi HW. It is reasonable to represent as a GPU rather >> > than regulator. >> >> If it is for power then it has to go via regulator. It does not make >> sense to directly control the gpio inside the wifi driver. > >As far as the board goes, WF_EN is just a GPIO signal to the WiFi card; >it doesn't gate power to the card. If it gates power inside the card, >that's an internal implementation detail of the card, and something I'd >be fine with the driver knowing directly, and hence I'm OK with representing >this as a GPIO rather than a regulator - that's what it is externally to the WiFi device. Because these gpio is just for wifi device, could we use the rfkill-gpio driver for this isse? We just need to add DT support in rfkill-gpio driver and add a device node in the DT. And the user also can use the rfkill interface to control the wifi device. > >(BTW everyone, many of the emails in this thread are awfully formatted >- top-posted and not word- wrapped. It's very hard to read them... I tried to reformat everything and fix it in this email) -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
