void init_protection(struct mxs_info *info)
{
enum ddi_power_5v_status pmu_5v_status;
uint16_t battery_voltage;
pmu_5v_status = ddi_power_GetPmu5vStatus();
battery_voltage = ddi_power_GetBattery();
/* InitializeFiqSystem(); */
ddi_power_InitOutputBrownouts();
if (info->powersource == NO_VDD5V_SOURCE) {
ddi_power_EnableBatteryBoInterrupt(true);
return;
}
/* if we start the kernel with 4p2 already started
* by the bootlets, we need to hand off from this
* state to the kernel 4p2 enabled state.
*/
if ((pmu_5v_status == existing_5v_connection) &&
ddi_power_check_4p2_bits()) {
ddi_power_enable_5v_disconnect_detection();
/* includes VBUS DROOP workaround for errata */
ddi_power_init_4p2_protection();
/* if we still have our 5V connection, we can disable
* battery brownout interrupt. This is because the
* VDD5V DROOP IRQ handler will also shutdown if battery
* is browned out and it will enable the battery brownout
* and bring VBUSVALID_TRSH level back to a normal level
* which caused the hardware battery brownout shutdown
* to be enabled. The benefit of this is that device
* that have detachable batteries (or devices going through
* the assembly line and running this firmware to test
* with) can avoid shutting down if 5V is present and
* battery voltage goes away.
*/
ddi_power_EnableBatteryBoInterrupt(false);
info->sm_5v_connection_status = _5v_connected_verified;
} else {
#ifdef DEBUG_IRQS
if (battery_voltage <
OS_SHUTDOWN_BATTERY_VOLTAGE_THRESHOLD_MV) {
printk(KERN_CRIT "Polled battery voltage measurement is\
less than %dmV. Kernel should be halted/\
shutdown\n",
OS_SHUTDOWN_BATTERY_VOLTAGE_THRESHOLD_MV);
return;
}
#endif
info->sm_5v_connection_status = _5v_disconnected_verified;
ddi_power_EnableBatteryBoInterrupt(true);
}
/* all brownouts are now handled software fiqs. We
* can now disable the hardware protection mechanisms
* because leaving them on yields ~2kV ESD level
* versus ~4kV ESD levels when they are off. This
* difference is suspected to be cause by the fast
* falling edge pswitch functionality being tripped
* by ESD events. This functionality is disabled
* when PWD_OFF is disabled.
*/
#ifdef DISABLE_HARDWARE_PROTECTION_MECHANISMS
__raw_writel(BM_POWER_RESET_PWD_OFF,
HW_POWER_RESET_SET_ADDR);
#endif
}
static void check_and_handle_5v_connection(struct mxs_info *info)
{
switch (ddi_power_GetPmu5vStatus()) {
case new_5v_connection:
if (info->is_5v_irq_detected == 0) {
/* we must wait for irq_vdd5v handler run first to
reset info->sm_new_5v_connection_jiffies.
Otherwise the debounce checking is wrong.
*/;
break;
}
info->is_5v_irq_detected = 0;
ddi_power_enable_5v_disconnect_detection();
info->sm_5v_connection_status = _5v_connected_unverified;
case existing_5v_connection:
if (info->sm_5v_connection_status != _5v_connected_verified) {
/* we allow some time to pass before considering
* the 5v connection to be ready to use. This
* will give the USB system time to enumerate
* (coordination with USB driver to be added
* in the future).
*/
/* handle jiffies rollover case */
if ((jiffies - info->sm_new_5v_connection_jiffies)
< 0) {
info->sm_new_5v_connection_jiffies = jiffies;
break;
}
if ((jiffies_to_msecs(jiffies -
info->sm_new_5v_connection_jiffies)) >
_5V_DEBOUNCE_TIME_MS) {
info->sm_5v_connection_status =
_5v_connected_verified;
dev_dbg(info->dev,
"5v connection verified\n");
if (info->onboard_vbus5v) {
if (regulator_is_enabled(
info->onboard_vbus5v) > 0) {
info->onboard_vbus5v_online = 1;
pr_debug("When supply from \
onboard vbus 5v ,\
DO NOT switch to 4p2 \n");
break;
}
}
#ifdef CONFIG_MXS_VBUS_CURRENT_DRAW
#ifdef CONFIG_USB_GADGET
/* if there is USB 2.0 current limitation requirement,
* waiting for USB enum done.
*/
if ((__raw_readl(REGS_POWER_BASE + HW_POWER_5VCTRL)
& BM_POWER_5VCTRL_CHARGE_4P2_ILIMIT) ==
(0x20 << BP_POWER_5VCTRL_CHARGE_4P2_ILIMIT)) {
dev_info(info->dev, "waiting USB enum done...\r\n");
}
while ((__raw_readl(REGS_POWER_BASE + HW_POWER_5VCTRL)
& BM_POWER_5VCTRL_CHARGE_4P2_ILIMIT)
== (0x20 << BP_POWER_5VCTRL_CHARGE_4P2_ILIMIT)) {
msleep(50);
}
#endif
#endif
ddi_power_Enable4p2(450);
/* part of handling for errata. It is
* now "somewhat" safe to
* turn on vddio interrupts again
*/
ddi_power_enable_vddio_interrupt(true);
}
}
static void check_and_handle_5v_connection(struct stmp3xxx_info *info)
{
switch (ddi_power_GetPmu5vStatus()) {
case new_5v_connection:
ddi_power_enable_5v_disconnect_detection();
info->sm_5v_connection_status = _5v_connected_unverified;
case existing_5v_connection:
if (info->sm_5v_connection_status != _5v_connected_verified) {
/* we allow some time to pass before considering
* the 5v connection to be ready to use. This
* will give the USB system time to enumerate
* (coordination with USB driver to be added
* in the future).
*/
/* handle jiffies rollover case */
if ((jiffies - info->sm_new_5v_connection_jiffies)
< 0) {
info->sm_new_5v_connection_jiffies = jiffies;
break;
}
if ((jiffies_to_msecs(jiffies -
info->sm_new_5v_connection_jiffies)) >
_5V_DEBOUNCE_TIME_MS) {
info->sm_5v_connection_status =
_5v_connected_verified;
dev_info(info->dev,
"5v connection verified\n");
ddi_power_Enable4p2(450);
/* part of handling for errata. It is
* now "somewhat" safe to
* turn on vddio interrupts again
*/
ddi_power_enable_vddio_interrupt(true);
}
}
break;
case new_5v_disconnection:
ddi_bc_SetDisable();
ddi_bc_SetCurrentLimit(0);
if (info->regulator)
regulator_set_current_limit(info->regulator, 0, 0);
info->is_usb_online = 0;
info->is_ac_online = 0;
info->sm_5v_connection_status = _5v_disconnected_unverified;
case existing_5v_disconnection:
if (info->sm_5v_connection_status !=
_5v_disconnected_verified) {
if ((jiffies - info->sm_new_5v_disconnection_jiffies)
< 0) {
info->sm_new_5v_connection_jiffies = jiffies;
break;
}
if ((jiffies_to_msecs(jiffies -
info->sm_new_5v_disconnection_jiffies)) >
_5V_DEBOUNCE_TIME_MS) {
info->sm_5v_connection_status =
_5v_disconnected_verified;
ddi_power_execute_5v_to_battery_handoff();
ddi_power_enable_5v_connect_detection();
/* part of handling for errata.
* It is now safe to
* turn on vddio interrupts again
*/
ddi_power_enable_vddio_interrupt(true);
dev_info(info->dev,
"5v disconnection handled\n");
}
}
break;
}
}
