Hi,
On 07-04-15 22:53, Simon Glass wrote:
Hi,
On 6 April 2015 at 02:43, Hans de Goede <hdego...@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 <cont...@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 <cont...@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 on
devices
+ with slaves connected to the bus or with pins exposed through
e.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:
0) Get the devicemode usb patches merged in to u-boot-dm/next
Then on top pf u-boot-dm/next:
1) 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.
If you look at:
board/sunxi/MAINTAINERS
And then the large block at the top, that lists the 30+ boards I've,
or at least it lists all the boards for which I've added support to
upstream u-boot I still have a couple which I need to add ...
Anyways, I should be able to test this on say 2 boards of each soc
generation, which should shake out most (if not all) bugs. The limit
here is not hardware access but how much time I want to spend on
testing :)
2) Start using dm for usb on sunxi
3) Enable ohci support on sunxi boards next to ehci
That's not currently supported, but I could perhaps take a look at it.
Correct, but it is desirable so that plugging in a usb keyboard
directly (without a usb-2 hub between the board and the keyboard)
will work.
4) 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...
Not sure what you mean by paying the 'tax' here, I'm hoping that with
the groundwork you've done moving over other boards becomes a pretty
mechanical process, other then the testing.
If someone can provide me with a git tree / branch with all boards
converted I can spend a couple of saturdays / sundays / evenings
on testing, picking boards which I know will exercise different
code paths.
Regards,
Hans
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