From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexandre Belloni Subject: Re: How to support SDIO wifi/bt in DT Date: Fri, 17 Jan 2014 11:14:56 +0100 Message-ID: <20140117101456.GD2348@piout.net> References: <20140116133649.GV15937@n2100.arm.linux.org.uk> <3215037.8HVCjAeS8g@wuerfel> <20140116195819.GY15937@n2100.arm.linux.org.uk> <20140117093909.GB2348@piout.net> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="llIrKcgUOe3dCx0c" Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-mmc-owner@vger.kernel.org To: Chen-Yu Tsai Cc: Olof Johansson , "devicetree@vger.kernel.org" , "linux-mmc@vger.kernel.org" , Russell King - ARM Linux , Arnd Bergmann , "linux-arm-kernel@lists.infradead.org" List-Id: devicetree@vger.kernel.org --llIrKcgUOe3dCx0c Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Jan 17, 2014 at 06:06:41PM +0800, Chen-Yu Tsai wrote : > On Fri, Jan 17, 2014 at 5:39 PM, Alexandre Belloni > wrote: > > Maybe it is not completely related but I think it needs to be thought > > about while you are it: > > > > The TI wilink chips (TiWi, wl12xx, wl18xx) have wifi on SDIO and BT on > > UART but they share the same clock. So, the next question would be what > > if I just want to enable one or the other (and take that decision at > > runtime) ? >=20 > Some Broadcom chips (BCM4329/4330) and the AP6210 found on CubieTruck > are like this as well. In our case, the SD/MMC host driver hasn't been > mainlined yet. But BT on UART is independent and usable. >=20 > > Where do I put the pinctrl/clocks/regulators in the DT ? I guess it can > > become an issue to enable both WiFi and BT at the same time if both SDIO > > and UART are trying to handle the same pinctrl and regulators. >=20 > Shouldn't the clocks and regulators be registered in the DT _AS_ clocks > and regulators? fixed-regulator already accepts GPIO lines. fixed-rate-cl= ock > mentions GPIOs in DT bindings, but doesn't seem to use them in the code. > We'd still need a device to tie them to, especially in the UART use case. >=20 Yeah, I meant if you tie your clock/pinctrl/reset/regulator to both the BT and the WiFI nodes because it is shared, you'll at least get a warning or one of the two won't be working. > Or we could try rfkill devices. Not saying it's the correct way, but it is > a solution. >=20 You'll get the same issue there. Two rfkill devices sharing the same clock or reset for example. --=20 Alexandre Belloni, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com --llIrKcgUOe3dCx0c Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.14 (GNU/Linux) iQIcBAEBCAAGBQJS2QKfAAoJEKbNnwlvZCyz0zUP/j988Zb8a8pjqzTpgAZHwB9P 3ggwAfjeDZCl04Bs0wRleFmS1m30FpcIxpyE5PlnMU0BBQgMThx4t0f0CdxXK05j clufckWZqTRcMo7f3TCjP34l7uxJl4vwrkbKJsS+vnSC8whkny1zgvW95oR0QvOa 9pdTzCMPA8nJbHe+lWZf6gGyeb9z/pxHqMXv1gPFMm3T5SFCTu7Ky4QFKGw5N45U saOAog+y6RRabpM1dN98PFyDm99wP6y6HmV+zl0D+CLRrWykrb446rLZ3UEHtJLI xsvdSl/Wwy4VYIwZOLNLB1eG6iLwtMj3x+IhsxdUBnson8Pkn1bjes7E5+q+eO4B 48Zz4z6ESajosKsCK1oRdzRmL7crV/kcuhJwq535Ef28UJKkO742HKYafuYo3vZO AN+wn5PisXGtcpoTz7YRUE20XliAJPdyjvreWtrgJvbWEIvEkjtJsmED2uvwVnWc BN0q2HZGSbFO73Y4AMHTuiwURJqv+kQNKdqpZweuO90UOMEwdFxAP1zosCxdWg1Z cSWhMY3SnXKfWFpfumTh66z6pqYwLTbqHBTCdbkiPvgOGqVnYhaTQ9lecZInFi5q Z9Rwc+52TBAErcwOfr2CQO/bHLQ35V1ig6Bs+OY8BCGJzkx/4mfhLP1gzOTkkXtQ op8MMh80FfwIHeZve8lj =ROgt -----END PGP SIGNATURE----- --llIrKcgUOe3dCx0c--