From ef976e6387c19b49232618493653ebfdd132d676 Mon Sep 17 00:00:00 2001 From: Wonjoon Lee Date: Fri, 27 Jan 2017 17:00:03 -0800 Subject: [PATCH] bd9995x: more delay time between chg_en and vsys_set The nvdc voltage has a kind of deep, so that rarely observed NVDC down at this point because of back-boosting. Our sequence to enable charger bit and setting vsysreg is correct but rohm introduce charger may need some more time to be stable when between chg_en and vsys_set to start charge BUG=chrome-os-partner:60380 BRANCH=gru TEST=Manual on kevin, trigger battery disconnect, re-attach AC, verify system boots cleanly. and see voltage probing on c54@60380 Change-Id: Ic05091379322ffaac16fe827a47345c76c85f3e5 Signed-off-by: Wonjoon Lee Reviewed-on: https://chromium-review.googlesource.com/434252 Commit-Ready: Shawn N Tested-by: Shawn N Reviewed-by: Shawn N --- driver/charger/bd9995x.c | 34 +++++++++++++++++++++++----------- 1 file changed, 23 insertions(+), 11 deletions(-) diff --git a/driver/charger/bd9995x.c b/driver/charger/bd9995x.c index c668aa5260..e28eeb0db2 100644 --- a/driver/charger/bd9995x.c +++ b/driver/charger/bd9995x.c @@ -541,19 +541,31 @@ int charger_get_status(int *status) int charger_set_mode(int mode) { - int rv; + int rv, inhibit_chg; + static int inhibit_chg_prev = -1; - if (mode & CHARGE_FLAG_INHIBIT_CHARGE) { - rv = bd9995x_set_vsysreg(BD9995X_DISCHARGE_VSYSREG); - msleep(50); - rv |= bd9995x_charger_enable(0); - } else { - rv = bd9995x_charger_enable(1); - msleep(1); - rv |= bd9995x_set_vsysreg(BD9995X_CHARGE_VSYSREG); + inhibit_chg = mode & CHARGE_FLAG_INHIBIT_CHARGE; + + if (inhibit_chg != inhibit_chg_prev) { + if (inhibit_chg) { + rv = bd9995x_set_vsysreg(BD9995X_DISCHARGE_VSYSREG); + msleep(50); + rv |= bd9995x_charger_enable(0); + } else { + rv = bd9995x_charger_enable(1); + /* + * BGATE capacitor max : 0.1uF + 20% + * Charge MOSFET threshold max : 2.8V + * BGATE charge pump current min : 3uA + * T = C * V / I so, Tmax = 112ms + */ + msleep(115); + rv |= bd9995x_set_vsysreg(BD9995X_CHARGE_VSYSREG); + } + inhibit_chg_prev = inhibit_chg; + if (rv) + return rv; } - if (rv) - return rv; if (mode & CHARGE_FLAG_POR_RESET) { rv = bd9995x_por_reset();