diff options
| author | Bill Richardson <wfrichar@chromium.org> | 2014-10-21 14:21:45 -0700 |
|---|---|---|
| committer | chrome-internal-fetch <chrome-internal-fetch@google.com> | 2014-10-22 02:23:39 +0000 |
| commit | 8cd9856cf8ef193ea094cf91c67e9aff25b2b521 (patch) | |
| tree | 966a17e7cb8edf8fd6ae8ad6b410fd4b124759e1 /board/samus/board.c | |
| parent | 7eaa290c35a1ca5571854c7d31a5a125af665b65 (diff) | |
| download | chrome-ec-8cd9856cf8ef193ea094cf91c67e9aff25b2b521.tar.gz | |
samus: change fan RPM values, enable fast-start
Updating the fan speeds according to the manufacturer's specs.
The fan vendor recommends that the minimum fan speed be a 20%
duty cycle. Since the built-in fan controller has a tach-based
feedback loop, I'm using the RPM value instead of the duty cycle
(20% is 2286 RPM, according to the vendor).
The vendor also wants a 30% duty cycle to start turning, but the
built-in fan controller provides support for fast-start too. The
controller's minimum fast-start duty cycle is 50%, but it also
has a programmable number of revolutions that it will wait before
backing off.
Holding my ear down close to the fans while they start and stop,
it seems that the minimum 2 revolution start period is sufficient
and provides the least noise. Of course, since I've never had any
problems starting the fans directly at 1000 RPM this noise is a
little more noticeable than that. It's quite possible that the
built-in controller is smart enough to make 1000 RPM work by
bumping the duty cycle up until the fans turn even if the fans
don't like it.
BUG=chrome-os-partner:32892
BRANCH=ToT,samus
TEST=manual
Listen closely and run the EC console "faninfo" command to see
the fans start and stop as the system boots and idles.
Change-Id: I47c9e7cef3f9f4bd815a13032fe10234decd62ed
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/224830
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Diffstat (limited to 'board/samus/board.c')
| -rw-r--r-- | board/samus/board.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/board/samus/board.c b/board/samus/board.c index 9d2feb93a8..08dae68780 100644 --- a/board/samus/board.c +++ b/board/samus/board.c @@ -105,16 +105,16 @@ BUILD_ASSERT(ARRAY_SIZE(pwm_channels) == PWM_CH_COUNT); /* Physical fans. These are logically separate from pwm_channels. */ const struct fan_t fans[] = { - {.flags = FAN_USE_RPM_MODE, - .rpm_min = 1000, - .rpm_max = 6500, + {.flags = FAN_USE_RPM_MODE | FAN_USE_FAST_START, + .rpm_min = 2286, + .rpm_max = 6350, .ch = 2, .pgood_gpio = -1, .enable_gpio = -1, }, - {.flags = FAN_USE_RPM_MODE, - .rpm_min = 1000, - .rpm_max = 6500, + {.flags = FAN_USE_RPM_MODE | FAN_USE_FAST_START, + .rpm_min = 2286, + .rpm_max = 6350, .ch = 3, .pgood_gpio = -1, .enable_gpio = -1, |