coreboot-libre-fam15h-rdimm/3rdparty/chromeec/driver/bc12/max14637.c

194 lines
5.3 KiB
C

/* Copyright 2017 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
/*
* MAX14637 USB BC 1.2 Charger Detector driver.
*
* NOTE: The driver assumes that CHG_AL_N and SW_OPEN are not connected,
* therefore the value of CHG_DET indicates whether the source is NOT a
* low-power standard downstream port (SDP). In order to use higher currents,
* the system will have to charge ramp.
*/
#include "max14637.h"
#include "cannonlake.h"
#include "charge_manager.h"
#include "chipset.h"
#include "common.h"
#include "console.h"
#include "gpio.h"
#include "power.h"
#include "task.h"
#include "tcpm.h"
#include "timer.h"
#include "usb_charge.h"
#include "usb_pd.h"
#include "util.h"
#define CPRINTS(format, args...) cprints(CC_USBPD, format, ## args)
#if defined(CONFIG_CHARGE_RAMP_SW) || defined(CONFIG_CHARGE_RAMP_HW)
/**
* Returns true if the charger detect pin is activated.
*
* @parm cfg driver for chip to read the charger detect pin for.
* @return 1 if charger detect is activated (high when active high or
* low with active low), otherwise 0.
*/
static int is_chg_det_activated(const struct max14637_config_t * const cfg)
{
return !!gpio_get_level(cfg->chg_det_pin) ^
!!(cfg->flags & MAX14637_FLAGS_CHG_DET_ACTIVE_LOW);
}
#endif
/**
* Activates the Chip Enable GPIO based on the enabled value.
*
* @param cfg driver for chip that will set chip enable gpio.
* @param enable 1 to activate gpio (high for active high and low for active
* low).
*/
static void activate_chip_enable(
const struct max14637_config_t * const cfg, const int enable)
{
gpio_set_level(
cfg->chip_enable_pin,
!!enable ^ !!(cfg->flags & MAX14637_FLAGS_ENABLE_ACTIVE_LOW));
}
/**
* Perform BC1.2 detection and update charge manager.
*
* @param port: The Type-C port where VBUS is present.
*/
static void bc12_detect(const int port)
{
const struct max14637_config_t * const cfg = &max14637_config[port];
struct charge_port_info new_chg;
/*
* Enable the IC to begin detection and connect switches if necessary.
*/
activate_chip_enable(cfg, 1);
new_chg.voltage = USB_CHARGER_VOLTAGE_MV;
#if defined(CONFIG_CHARGE_RAMP_SW) || defined(CONFIG_CHARGE_RAMP_HW)
/*
* Apple or TomTom charger detection can take as long as 600ms. Wait a
* little bit longer for margin.
*/
msleep(630);
/*
* The driver assumes that CHG_AL_N and SW_OPEN are not connected,
* therefore an activated CHG_DET indicates whether the source is NOT a
* low-power standard downstream port (SDP). The system will have to
* ramp the current to determine the limit.
*/
new_chg.current = is_chg_det_activated(cfg) ? 2400 : 500;
#else
/*
* If the board doesn't support charge ramping, then assume the lowest
* denominator; that is assume the charger detected is a weak dedicated
* charging port (DCP) which can only supply 500mA.
*/
new_chg.current = 500;
#endif /* !defined(CONFIG_CHARGE_RAMP_SW && CONFIG_CHARGE_RAMP_HW) */
charge_manager_update_charge(CHARGE_SUPPLIER_OTHER, port, &new_chg);
}
/**
* Turn off the MAX14637 detector.
*
* @param port: Which USB Type-C port's BC1.2 detector to turn off.
*/
static void power_down_ic(const int port)
{
const struct max14637_config_t * const cfg = &max14637_config[port];
/* Turn off the IC. */
activate_chip_enable(cfg, 0);
/* Let charge manager know there's no more charge available. */
charge_manager_update_charge(CHARGE_SUPPLIER_OTHER, port, NULL);
}
/**
* If VBUS is present, determine the charger type, otherwise power down the IC.
*
* @param port: Which USB Type-C port to examine.
*/
static void detect_or_power_down_ic(const int port)
{
int vbus_present;
#ifdef CONFIG_USB_PD_VBUS_DETECT_TCPC
vbus_present = tcpm_get_vbus_level(port);
#else
vbus_present = pd_snk_is_vbus_provided(port);
#endif /* !defined(CONFIG_USB_PD_VBUS_DETECT_TCPC) */
if (vbus_present) {
#if defined(CONFIG_POWER_PP5000_CONTROL) && defined(HAS_TASK_CHIPSET)
/* Turn on the 5V rail to allow the chip to be powered. */
power_5v_enable(task_get_current(), 1);
#endif
bc12_detect(port);
} else {
power_down_ic(port);
#if defined(CONFIG_POWER_PP5000_CONTROL) && defined(HAS_TASK_CHIPSET)
/* Issue a request to turn off the rail. */
power_5v_enable(task_get_current(), 0);
#endif
}
}
void usb_charger_task(void *u)
{
const int port = (intptr_t)u;
uint32_t evt;
ASSERT(port >= 0 && port < CONFIG_USB_PD_PORT_COUNT);
detect_or_power_down_ic(port);
while (1) {
evt = task_wait_event(-1);
if (evt & USB_CHG_EVENT_VBUS)
detect_or_power_down_ic(port);
}
}
void usb_charger_set_switches(int port, enum usb_switch setting)
{
/*
* The MAX14637 automatically sets up the USB 2.0 high-speed switches.
*/
}
#if defined(CONFIG_CHARGE_RAMP_SW) || defined(CONFIG_CHARGE_RAMP_HW)
int usb_charger_ramp_allowed(int supplier)
{
/*
* Due to the limitations in the application of the MAX14637, we
* don't quite know exactly what we're plugged into. Therefore,
* the supplier type will be CHARGE_SUPPLIER_OTHER.
*/
return supplier == CHARGE_SUPPLIER_OTHER;
}
int usb_charger_ramp_max(int supplier, int sup_curr)
{
/* Use the current limit that was decided by the MAX14637. */
if (supplier == CHARGE_SUPPLIER_OTHER)
return sup_curr;
else
return 500;
}
#endif /* CONFIG_CHARGE_RAMP_SW || CONFIG_CHARGE_RAMP_HW */