[RFC PATCHv2 1/2] Export SoC info through sysfs

On Fri, Mar 11, 2011 at 07:58:16PM +0200, Eduardo Valentin wrote:

Hello,

On Fri, Mar 11, 2011 at 07:52:57AM -0800, ext Greg KH wrote:

quoted

On Fri, Mar 11, 2011 at 03:32:51PM +0100, Arnd Bergmann wrote:

quoted

On Friday 11 March 2011, Maxime Coquelin wrote:

quoted

Common base to export System-on-Chip related informations through sysfs.

Creation of a "socinfo" directory under /sys/.
Creation of SoC information entries.

Signed-off-by: Maxime COQUELIN <redacted>

I think it's better than the previous patch to create an
artificial device in /sys/devices/system/socinfo, but I'd
still prefer the information to be attached to a real device
that represents the SOC, as I explained in the discussion with
Linus Walleij.

You should definitely add Greg on Cc, as he's maintaining sysfs
and certainly has an opininion here.

	Arnd

quoted

---
 Documentation/ABI/testing/sysfs-socinfo |   16 ++++++
 drivers/base/Kconfig                    |    3 +
 drivers/base/Makefile                   |    1 +
 drivers/base/soc.c                      |   79 +++++++++++++++++++++++++++++++
 include/linux/sys_soc.h                 |   50 +++++++++++++++++++
 5 files changed, 149 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/ABI/testing/sysfs-socinfo
 create mode 100644 drivers/base/soc.c
 create mode 100644 include/linux/sys_soc.h

diff --git a/Documentation/ABI/testing/sysfs-socinfo b/Documentation/ABI/testing/sysfs-socinfo
new file mode 100644
index 0000000..afd9da2
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-socinfo

@@ -0,0 +1,16 @@
+What:		/sys/socinfo
+Date:		March 2011
+contact:	Maxime Coquelin <maxime.coquelin-nonst@stericsson.com>
+Description:
+		The /sys/socinfo directory contains information about the
+		System-on-Chip.	It is only available if platform implements it.
+		This directory contains two kind of attributes :
+			- common attributes: 
+				* machine: the name of the machine.
+				* family: the family name of the SoC
+			- SoC-specific attributes: The SoC vendor can declare attributes
+			  to export some strings to user-space, like the serial-number for
+			  example.
+
+Users:
+		User-space applications which needs these kind of attributes.

I thought I rejected this the last time it came around?

Greg,

Do you mind sharing the link of the thread where you have reject this?

I don't remember it, you can search as well as I can :)

quoted

I still fail to understand why this is needed, please provide more
information about why you feel this is something that the kernel needs.

In case of OMAP, there are few ids that we would expose to user space,
like serial, revision and die id to quote some from top of my mind.
I must emphasize  that these are not data from CPU at all, they belong
to SoC itself.

I understand, but note that there could be multiple SoC devices, right?
How will this code support that?

Make this a "real" device not /sys/socinfo please.  It can be a platform
device that export the needed information, that way you can have
multiple ones.

thanks,

greg k-h