diff options
| author | Julius Werner <jwerner@chromium.org> | 2021-02-10 14:25:21 -0800 |
|---|---|---|
| committer | Julius Werner <jwerner@chromium.org> | 2021-02-12 22:17:53 +0000 |
| commit | a39c5772572dff6f324ef5437d36223afa0f7f69 (patch) | |
| tree | 2c83e3a1bb2baa525dea5ebc568345b10a25e814 /src/mainboard/google/trogdor/mainboard.c | |
| parent | 43ccd6a4ad09343dd914b9f4beb904768e191e74 (diff) | |
trogdor: Add fingerprint power sequencing
Some Trogdor variants will include a fingerprint sensor, so this patch
adds support for its power sequencing. There is a requirement that the
fingerprint power needs to be *off* for at least 200ms, and when it is
turned back on it needs to stabilize for at least 3.5ms before taking
the FPMCU out of reset. We meet these timing requirements by splitting
the sequence across bootblock, romstage and ramstage. On current Trogdor
boards we measured <end of bootblock> to <end of romstage> at ~430ms and
<end of romstage> to <start of ramstage> at 12ms, so we easily meet the
required numbers this way.
BRANCH=trogdor
BUG=b:170284663
Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: Iccd77e6e1c378110fca2b2b7ff1f534fce54f8ea
Reviewed-on: https://review.coreboot.org/c/coreboot/+/50504
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Shelley Chen <shchen@google.com>
Diffstat (limited to 'src/mainboard/google/trogdor/mainboard.c')
| -rw-r--r-- | src/mainboard/google/trogdor/mainboard.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/src/mainboard/google/trogdor/mainboard.c b/src/mainboard/google/trogdor/mainboard.c index 7465c63627..9bf8507d64 100644 --- a/src/mainboard/google/trogdor/mainboard.c +++ b/src/mainboard/google/trogdor/mainboard.c @@ -110,6 +110,11 @@ static void display_startup(void) static void mainboard_init(struct device *dev) { + /* Take FPMCU out of reset. Power was already applied + in romstage and should have stabilized by now. */ + if (CONFIG(TROGDOR_HAS_FINGERPRINT)) + gpio_output(GPIO_FP_RST_L, 1); + setup_usb(); qi2s_configure_gpios(); load_qup_fw(); |