diff options
| author | Joel Stanley <joel@jms.id.au> | 2020-07-28 12:25:27 +0930 |
|---|---|---|
| committer | Joel Stanley <joel@jms.id.au> | 2020-09-10 12:26:43 +0930 |
| commit | 4a851d714eadeabd65c7e321a2e7830f77d945c4 (patch) | |
| tree | c8c917f9c05ec83efd97474e0bb2b4307e6f5bab /Documentation/ABI | |
| parent | add6895188e49aa6b730d647ca896559370aa2be (diff) | |
fsi: aspeed: Support CFAM reset GPIO
Systems have a line for restting the remote CFAM. This is not part of
the FSI master, but is associated with it, so it makes sense to include
it in the master driver.
This exposes a sysfs interface to reset the cfam, abstracting away the
direction and polarity of the GPIO, as well as the timing of the reset
pulse. Userspace will be blocked until the reset pulse is finished.
The reset is hard coded to be in the range of (900, 1000) us. It was
observed with a scope to regularly be just over 1ms.
If the device tree property is not preset the driver will silently
continue.
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20200728025527.174503-6-joel@jms.id.au
Signed-off-by: Joel Stanley <joel@jms.id.au>
Diffstat (limited to 'Documentation/ABI')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-fsi | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-fsi b/Documentation/ABI/testing/sysfs-bus-fsi index 320697bdf41d..d148214181a1 100644 --- a/Documentation/ABI/testing/sysfs-bus-fsi +++ b/Documentation/ABI/testing/sysfs-bus-fsi @@ -36,3 +36,11 @@ Contact: linux-fsi@lists.ozlabs.org Description: Provides a means of reading/writing a 32 bit value from/to a specified FSI bus address. + +What: /sys/bus/platform/devices/../cfam_reset +Date: Sept 2020 +KernelVersion: 5.10 +Contact: linux-fsi@lists.ozlabs.org +Description: + Provides a means of resetting the cfam that is attached to the + FSI device. |