diff options
Diffstat (limited to 'common/usb_pd_policy.c')
| -rw-r--r-- | common/usb_pd_policy.c | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/common/usb_pd_policy.c b/common/usb_pd_policy.c index 118a04fbed..bfaccc8e29 100644 --- a/common/usb_pd_policy.c +++ b/common/usb_pd_policy.c @@ -4,6 +4,7 @@ */ #include "adc.h" #include "atomic.h" +#include "charge_manager.h" #include "common.h" #include "console.h" #include "flash.h" @@ -32,6 +33,140 @@ static int rw_flash_changed = 1; +#ifdef CONFIG_USB_PD_DUAL_ROLE +/* Cap on the max voltage requested as a sink (in millivolts) */ +static unsigned max_request_mv = -1; /* no cap */ + +/** + * Find PDO index that offers the most amount of power and stays within + * max_mv voltage. + * + * @param cnt the number of Power Data Objects. + * @param src_caps Power Data Objects representing the source capabilities. + * @param max_mv maximum voltage (or -1 if no limit) + * @return index of PDO within source cap packet + */ +static int pd_find_pdo_index(int cnt, uint32_t *src_caps, int max_mv) +{ + int i, uw, max_uw = 0, mv, ma; + int ret = -1; + + /* max_mv of -1 represents max limit */ + if (max_mv == -1) + max_mv = PD_MAX_VOLTAGE_MV; + + /* max voltage is always limited by this boards max request */ + max_mv = MIN(max_mv, PD_MAX_VOLTAGE_MV); + + /* Get max power that is under our max voltage input */ + for (i = 0; i < cnt; i++) { + mv = ((src_caps[i] >> 10) & 0x3FF) * 50; + if ((src_caps[i] & PDO_TYPE_MASK) == PDO_TYPE_BATTERY) { + uw = 250000 * (src_caps[i] & 0x3FF); + } else { + ma = (src_caps[i] & 0x3FF) * 10; + uw = ma * mv; + } + if ((uw > max_uw) && (mv <= max_mv)) { + ret = i; + max_uw = uw; + } + } + return ret; +} + +/** + * Extract power information out of a Power Data Object (PDO) + * + * @pdo Power data object + * @ma Current we can request from that PDO + * @mv Voltage of the PDO + */ +static void pd_extract_pdo_power(uint32_t pdo, uint32_t *ma, uint32_t *mv) +{ + int max_ma, uw; + *mv = ((pdo >> 10) & 0x3FF) * 50; + + if ((pdo & PDO_TYPE_MASK) == PDO_TYPE_BATTERY) { + uw = 250000 * (pdo & 0x3FF); + max_ma = 1000 * MIN(1000 * uw, PD_MAX_POWER_MW) / *mv; + } else { + max_ma = 10 * (pdo & 0x3FF); + max_ma = MIN(max_ma, PD_MAX_CURRENT_MA); + } + + *ma = max_ma; +} + +int pd_build_request(int cnt, uint32_t *src_caps, uint32_t *rdo, + uint32_t *ma, uint32_t *mv, enum pd_request_type req_type) +{ + int pdo_index, flags = 0; + int uw; + + if (req_type == PD_REQUEST_VSAFE5V) + /* src cap 0 should be vSafe5V */ + pdo_index = 0; + else + /* find pdo index for max voltage we can request */ + pdo_index = pd_find_pdo_index(cnt, src_caps, max_request_mv); + + /* If could not find desired pdo_index, then return error */ + if (pdo_index == -1) + return -EC_ERROR_UNKNOWN; + + pd_extract_pdo_power(src_caps[pdo_index], ma, mv); + uw = *ma * *mv; + if (uw < (1000 * PD_OPERATING_POWER_MW)) + flags |= RDO_CAP_MISMATCH; + + if ((src_caps[pdo_index] & PDO_TYPE_MASK) == PDO_TYPE_BATTERY) { + int mw = uw / 1000; + *rdo = RDO_BATT(pdo_index + 1, mw, mw, flags); + CPRINTF("Request [%d] %dmV %dmW", + pdo_index, *mv, mw); + } else { + *rdo = RDO_FIXED(pdo_index + 1, *ma, *ma, flags); + CPRINTF("Request [%d] %dmV %dmA", + pdo_index, *mv, *ma); + } + /* Mismatch bit set if less power offered than the operating power */ + if (flags & RDO_CAP_MISMATCH) + CPRINTF(" Mismatch"); + CPRINTF("\n"); + + return EC_SUCCESS; +} + +void pd_process_source_cap(int port, int cnt, uint32_t *src_caps) +{ +#ifdef CONFIG_CHARGE_MANAGER + uint32_t ma, mv; + int pdo_index; + + /* Get max power info that we could request */ + pdo_index = pd_find_pdo_index(cnt, src_caps, -1); + if (pdo_index < 0) + pdo_index = 0; + pd_extract_pdo_power(src_caps[pdo_index], &ma, &mv); + + /* Set max. limit, but apply 500mA ceiling */ + charge_manager_set_ceil(port, PD_MIN_MA); + pd_set_input_current_limit(port, ma, mv); +#endif +} + +void pd_set_max_voltage(unsigned mv) +{ + max_request_mv = mv; +} + +unsigned pd_get_max_voltage(void) +{ + return max_request_mv; +} +#endif /* CONFIG_USB_PD_DUAL_ROLE */ + #ifdef CONFIG_USB_PD_ALT_MODE #ifdef CONFIG_USB_PD_ALT_MODE_DFP |