From c8557a0e4e7c3181bb40b9b068e5b79b38d7dfe1 Mon Sep 17 00:00:00 2001 From: Devin Lu Date: Tue, 15 Nov 2016 14:04:37 +0800 Subject: [PATCH] pd: add PDO selection for choosing highest voltage pyro board is using 3S1P battery, it is near 13V. To avoid the charger entering buck-boost mode, sinking as higher voltage to get the higher power efficiency. BRANCH=none BUG=chrome-os-partner:59276 TEST=plug in pyro's charger (offering 20V@2.25A, 15V@3A, 9V@3A and 5V@3A), see it selecting 20V as below: C1 st2 C1 st3 C1 st15 C1 st3 C1 st6 Req C1 [1] 5000mV 3000mA [6391.078044 New chg p1] [6391.081020 Ramp reset: st1] [6391.081664 CL: p1 s0 i500 v20000] C1 st7 C1 st8 C1 st9 [6391.192437 Ramp reset: st1] [6391.193339 CL: p1 s0 i3000 v5000] Req C1 [4] 20000mV 2250mA C1 st7 C1 st8 C1 st9 [6391.457545 Ramp reset: st1] [6391.458340 CL: p1 s0 i2250 v20000] C1 st27 C1 st9 [6392.081252 AC on] [6392.113477 charge_request(0mV, 0mA)] [6393.116998 Ramp p1 st5 2250mA 2250mA] plug in other charger (offering 15V@3A, 12V@3A and 5V@3A), see it selecting 15V as below: C1 st2 C1 st3 C1 st15 C1 st3 C1 st6 Req C1 [1] 5000mV 3000mA [6636.084963 New chg p1] [6636.087117 Ramp reset: st1] [6636.087786 CL: p1 s0 i500 v15000] C1 st7 C1 st8 C1 st9 [6636.165409 Ramp reset: st1] [6636.166314 CL: p1 s0 i3000 v5000] Req C1 [3] 15000mV 3000mA C1 st7 C1 st8 C1 st9 C1 st27 C1 st9 [6637.092559 AC on] [6637.125043 charge_request(0mV, 0mA)] [6638.091158 Ramp p1 st5 3000mA 3000mA] [6639.374815 charge_request(13040mV, 3712mA)] Change-Id: I74fe4cbd6b9d1b416a94eec3fe944a9b725f0ced Signed-off-by: Devin Lu Reviewed-on: https://chromium-review.googlesource.com/411621 Commit-Ready: Shawn N Reviewed-by: Shawn N --- board/pyro/board.h | 3 +++ common/usb_pd_policy.c | 31 ++++++++++++++++++------------- 2 files changed, 21 insertions(+), 13 deletions(-) diff --git a/board/pyro/board.h b/board/pyro/board.h index d95e12557a..1c63f8cb47 100644 --- a/board/pyro/board.h +++ b/board/pyro/board.h @@ -294,6 +294,9 @@ enum pyro_board_version { #define PD_MAX_CURRENT_MA 3000 #define PD_MAX_VOLTAGE_MV 20000 +/* The higher the input voltage, the higher the power efficiency. */ +#define PD_PREFER_HIGH_VOLTAGE + /* Reset PD MCU */ void board_reset_pd_mcu(void); diff --git a/common/usb_pd_policy.c b/common/usb_pd_policy.c index 5a37a943e3..1fa53d5695 100644 --- a/common/usb_pd_policy.c +++ b/common/usb_pd_policy.c @@ -95,11 +95,11 @@ static unsigned max_request_mv = PD_MAX_VOLTAGE_MV; /* no cap */ */ static int pd_find_pdo_index(int cnt, uint32_t *src_caps, int max_mv) { - int i, uw, max_uw = 0, mv, ma; + int i, uw, mv, ma; int ret = -1; -#ifdef PD_PREFER_LOW_VOLTAGE - int cur_mv = 0; -#endif + int __attribute__((unused)) cur_mv = 0; + int cur_uw = 0; + int prefer_cur; /* max voltage is always limited by this boards max request */ max_mv = MIN(max_mv, PD_MAX_VOLTAGE_MV); @@ -118,21 +118,26 @@ static int pd_find_pdo_index(int cnt, uint32_t *src_caps, int max_mv) ma = MIN(ma, PD_MAX_CURRENT_MA); uw = ma * mv; } -#ifdef PD_PREFER_LOW_VOLTAGE + if (mv > max_mv) continue; uw = MIN(uw, PD_MAX_POWER_MW * 1000); - if ((uw > max_uw) || ((uw == max_uw) && mv < cur_mv)) { + prefer_cur = 0; + + /* Apply special rules in case of 'tie' */ +#ifdef PD_PREFER_LOW_VOLTAGE + if (uw == cur_uw && mv < cur_mv) + prefer_cur = 1; +#elif defined(PD_PREFER_HIGH_VOLTAGE) + if (uw == cur_uw && mv > cur_mv) + prefer_cur = 1; +#endif + /* Prefer higher power, except for tiebreaker */ + if (uw > cur_uw || prefer_cur) { ret = i; - max_uw = uw; + cur_uw = uw; cur_mv = mv; } -#else - if ((uw > max_uw) && (mv <= max_mv)) { - ret = i; - max_uw = uw; - } -#endif } return ret; }