fpga manager: add sysfs interface document
Add documentation under drivers/staging for new fpga manager's
sysfs interface.
Signed-off-by: Alan Tull <atull@opensource.altera.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/Documentation/ABI/testing/sysfs-class-fpga-manager b/Documentation/ABI/testing/sysfs-class-fpga-manager
new file mode 100644
index 0000000..23056c5
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-fpga-manager
@@ -0,0 +1,37 @@
+What: /sys/class/fpga_manager/<fpga>/name
+Date: August 2015
+KernelVersion: 4.3
+Contact: Alan Tull <atull@opensource.altera.com>
+Description: Name of low level fpga manager driver.
+
+What: /sys/class/fpga_manager/<fpga>/state
+Date: August 2015
+KernelVersion: 4.3
+Contact: Alan Tull <atull@opensource.altera.com>
+Description: Read fpga manager state as a string.
+ The intent is to provide enough detail that if something goes
+ wrong during FPGA programming (something that the driver can't
+ fix) then userspace can know, i.e. if the firmware request
+ fails, that could be due to not being able to find the firmware
+ file.
+
+ This is a superset of FPGA states and fpga manager driver
+ states. The fpga manager driver is walking through these steps
+ to get the FPGA into a known operating state. It's a sequence,
+ though some steps may get skipped. Valid FPGA states will vary
+ by manufacturer; this is a superset.
+
+ * unknown = can't determine state
+ * power off = FPGA power is off
+ * power up = FPGA reports power is up
+ * reset = FPGA held in reset state
+ * firmware request = firmware class request in progress
+ * firmware request error = firmware request failed
+ * write init = preparing FPGA for programming
+ * write init error = Error while preparing FPGA for
+ programming
+ * write = FPGA ready to receive image data
+ * write error = Error while programming
+ * write complete = Doing post programming steps
+ * write complete error = Error while doing post programming
+ * operating = FPGA is programmed and operating