jtag: drivers: bcm2835gpio: set 4ma drive, slow slew rate 07/3707/2
authorSean Cross <sean@xobs.io>
Thu, 18 Aug 2016 05:16:29 +0000 (05:16 +0000)
committerPaul Fertser <fercerpav@gmail.com>
Thu, 8 Dec 2016 12:34:09 +0000 (12:34 +0000)
commit1461237073e377d315799999b8e29f1605084449
tree9c1d46fc152bd9763bb8490c46358e95a3deaadf
parent50dd7207eaae9d2d1f02e7996135d6257c03b395
jtag: drivers: bcm2835gpio: set 4ma drive, slow slew rate

Both the drive strength and slew rate are currently set to very high
values.  This causes the waveforms to overshoot and be less reliable
when operating at high speed.

This patch lowers the slew rate and sets the drive strength to 4ma,
improving the waveform output.

Change-Id: I761d35cd64bc54a9e94043904ef00a003b056af0
Signed-off-by: Sean Cross <sean@xobs.io>
Reviewed-on: http://openocd.zylin.com/3707
Tested-by: jenkins
Reviewed-by: Paul Fertser <fercerpav@gmail.com>
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-by: Philipp Guehring <pg@futureware.at>
src/jtag/drivers/bcm2835gpio.c

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