Hi,
On 6 April 2015 at 02:43, Hans de Goede hdegoede@redhat.com wrote:
Hi Simon and Paul,
On 05-04-15 22:56, Paul Kocialkowski wrote:
Le dimanche 05 avril 2015 à 12:31 -0600, Simon Glass a écrit :
Hi Paul,
On 4 April 2015 at 14:49, Paul Kocialkowski contact@paulk.fr wrote:
Sunxi platforms come with at least 3 TWI (I2C) controllers and some platforms even have up to 5. This adds support for every controller on each supported platform, which is especially useful when using expansion ports on single-board- computers.
Signed-off-by: Paul Kocialkowski contact@paulk.fr
arch/arm/include/asm/arch-sunxi/cpu_sun4i.h | 7 +++ arch/arm/include/asm/arch-sunxi/gpio.h | 15 +++++- arch/arm/include/asm/arch-sunxi/i2c.h | 13 +++++ board/sunxi/Kconfig | 31 ++++++++++++ board/sunxi/board.c | 75 ++++++++++++++++++++++++++++- 5 files changed, 138 insertions(+), 3 deletions(-)
<snip>
diff --git a/board/sunxi/Kconfig b/board/sunxi/Kconfig index ccc2080..d3b5bad 100644 --- a/board/sunxi/Kconfig +++ b/board/sunxi/Kconfig @@ -269,6 +269,37 @@ config USB2_VBUS_PIN ---help--- See USB1_VBUS_PIN help text.
+config I2C1_ENABLE
bool "Enable I2C/TWI controller 1"default n---help---This allows enabling I2C/TWI controller 1 by muxing its pins,enabling
its clock and setting up the bus. This is especially useful ondevices
with slaves connected to the bus or with pins exposed throughe.g. an
expansion port/header.+config I2C2_ENABLE
bool "Enable I2C/TWI controller 2"default n---help---See I2C1_ENABLE help text.+if MACH_SUN6I || MACH_SUN7I +config I2C3_ENABLE
bool "Enable I2C/TWI controller 3"default n---help---See I2C1_ENABLE help text.+endif
+if MACH_SUN7I +config I2C4_ENABLE
bool "Enable I2C/TWI controller 4"default n---help---See I2C1_ENABLE help text.+endif
It seems wrong to me to add these when they are already in the device tree for the board. Can we not use that?
Well, Hans has a point when saying that some users may use those pins as GPIO while some others may use the TWI/I2C functions, so it makes sense to make this configurable via Kconfig instead of being statically defined.
If you would rather wait until we have driver model I2C on sunxi (mvtwsi, I think) then I'd be happy to do the conversion. It's pretty easy.
I would be happy to see U-Boot on sunxi use devicetree and driver model for TWI/I2C as well (provided users can still configure what busses to enable). Still, I'd like to see this getting merged as a short term solution.
How can we get sunxi moved over before there is an explosion of these sorts of things (as we have already seen with video options)?
I fully support moving sunxi over the devicemodel + devicetree in my mind the following steps need to be taken:
Get the devicemode usb patches merged in to u-boot-dm/next Then on top pf u-boot-dm/next:
Move all the sunxi boards over to use dm + dt like we're already doing for the pcduino
This could be a bit tricky unless someone has all the boards. I suppose if we do it at the very start of the merge window and then we have time to fix any problems.
Start using dm for usb on sunxi
Enable ohci support on sunxi boards next to ehci
That's not currently supported, but I could perhaps take a look at it.
- Move other stuff over on a step by step basis
Note that we will likely have a mix of Kconfig + devicetree for quite a while though since certain things which we support in u-boot are not supported in the kernel yet so they do not have stable devicetree bindings yet, video being the big one here.
Yes that makes things tricky.
I think Hans will know better (than myself) how to do this right.
Not really, other then having the the generic outline above in my head, I do not really have much experience with the devicemodel in u-boot yet, also I do not have all that much time to work one this, so help on this from you would certainly be very welcome. I can answer any sunxi questions you may have, and I believe it is safe to say that Simon can answer any device-model questions you may have.
Regards,
Hans
p.s.
Paul I'm still fine with taking your i2c patchset upstream for now, but I do agree with Simon that we need to move to the device model and the sooner we do that the better.
Yes - the problem is that no one person can pay the 'tax' of moving over, so we need to try to spread the effort on individuals who send patches...
Regards, Simon