android_kernel_samsung_msm8976/drivers/usb/usb-common.c

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/*
* Provides code common for host and device side USB.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation, version 2.
*
* If either host side (ie. CONFIG_USB=y) or device side USB stack
* (ie. CONFIG_USB_GADGET=y) is compiled in the kernel, this module is
* compiled-in as well. Otherwise, if either of the two stacks is
* compiled as module, this file is compiled as module as well.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/usb/ch9.h>
#include <linux/usb/of.h>
#include <linux/usb/otg.h>
const char *usb_otg_state_string(enum usb_otg_state state)
{
static const char *const names[] = {
[OTG_STATE_A_IDLE] = "a_idle",
[OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise",
[OTG_STATE_A_WAIT_BCON] = "a_wait_bcon",
[OTG_STATE_A_HOST] = "a_host",
[OTG_STATE_A_SUSPEND] = "a_suspend",
[OTG_STATE_A_PERIPHERAL] = "a_peripheral",
[OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall",
[OTG_STATE_A_VBUS_ERR] = "a_vbus_err",
[OTG_STATE_B_IDLE] = "b_idle",
[OTG_STATE_B_SRP_INIT] = "b_srp_init",
[OTG_STATE_B_PERIPHERAL] = "b_peripheral",
usb: phy-msm-usb: Add new B_CHARGER state to improve runtime PM handling OTG state machine work missing to handle events in fast PIPO or a rogue charger toggling VBUS very frequently and this results in extra runtime_put in B_IDLE state on BSV SET -> BSV SET. When device is entering system suspend and USB DCP charger is disconnected, then due to VBUS clear from PMIC, the device will be PM resumed and schedule the sm work for BSV clear. Now shortly just before running the disconnect work, BSV set event came and it will handle VBUS set condition in sm work and hence it did not take count, because dpm_prepare took count already. dpm_complete did not finish by this time where it drops the matching count which was taken by dpm_prepare. After DCP charger detection, dropped count hence pm count is 0. This should happen after dpm_prepare and before pm_suspend. Now the counter became negative. Because of this counter mismatch, SM work will not increment the count before processing the BSV set or clear events. Because of this runtime idle may put USB in LPM and a disconnect processing may still be running after USB entered into low power mode leading to unclocked access in charger block off. OTG_STATE_B_CHARGER state is used to handle connect and disconnects with DCP/PROP charger. If a charger connected followed by cable disconnect and before running the disconnect work BSV set event came. Controller driver relies on OTG state OTG_STATE_B_CHARGER to check for VBUS session valid for the disconnect case and change OTG state to OTG_STATE_B_IDLE to handle cancel the changer work. CRs-Fixed: 819308 Change-Id: I17b3b327cc5bd48d24e914e3497976ebb541e066 Signed-off-by: ChandanaKishori Chiluveru <cchilu@codeaurora.org>
2015-04-17 13:52:28 +00:00
[OTG_STATE_B_CHARGER] = "b_charger",
[OTG_STATE_B_WAIT_ACON] = "b_wait_acon",
[OTG_STATE_B_HOST] = "b_host",
usb: dwc3: Add new OTG state OTG_STATE_B_SUSPENDED This state is used to handle:- - Bus suspend followed by cable disconnect: pm usage count is incremented upon cable connect. Upon bus suspend, suspend interrupt kicks in otg state machine which moves device state to OTG_STATE_B_SUSPENDED from OTG_STATE_B_PERIPHERAL and decrements pm usage count. Upon cable unplug additional decrement of pm usage count is prevented. This state also takes care the handling of cable unplug followed by bus suspend interrupt. - Host initiated resume after bus suspend: Being in OTG_STATE_B_SUSPENDED after bus suspend, upon host initiated resume, wakeup interrupt kicks in otg state machine which moves device to OTG_STATE_B_PERIPHERAL state by incrementing pm usage count. - PC reboot with cable plugged in: After PC shutdown device goes to OTG_STATE_B_SUSPENDED state. After PC start power event irq thread kicks in otg state machine to move device to OTG_STATE_B_PERIPHERAL state and increments pm usage count. - Composition switch after bus suspend: dwc3_gadget_pullup() kicks in otg state machine to move device state from OTG_STATE_B_SUSPENDED to OTG_STATE_B_PERIPHERAL and increments pm usage count to prevent runtime suspend during device enumeration. Also, remove pm_runtime_set_active() which sets the PM runtime stauts as active to avoid pm_runtime_get_sync() failures which explicitly checks for runtime pm status. For example, if status is active, pm_runtime_get_sync() will just increments the counter without actually resuming the device. CRs-Fixed: 804457 Change-Id: Id33b81911ef3894a00802b3e553840b9447f6269 Signed-off-by: Hemant Kumar <hemantk@codeaurora.org> Signed-off-by: Azhar Shaikh <azhars@codeaurora.org>
2015-04-07 21:42:39 +00:00
[OTG_STATE_B_SUSPEND] = "b_suspend",
};
if (state < 0 || state >= ARRAY_SIZE(names))
return "UNDEFINED";
return names[state];
}
EXPORT_SYMBOL_GPL(usb_otg_state_string);
static const char *const speed_names[] = {
[USB_SPEED_UNKNOWN] = "UNKNOWN",
[USB_SPEED_LOW] = "low-speed",
[USB_SPEED_FULL] = "full-speed",
[USB_SPEED_HIGH] = "high-speed",
[USB_SPEED_WIRELESS] = "wireless",
[USB_SPEED_SUPER] = "super-speed",
};
const char *usb_speed_string(enum usb_device_speed speed)
{
if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
speed = USB_SPEED_UNKNOWN;
return speed_names[speed];
}
EXPORT_SYMBOL_GPL(usb_speed_string);
const char *usb_state_string(enum usb_device_state state)
{
static const char *const names[] = {
[USB_STATE_NOTATTACHED] = "not attached",
[USB_STATE_ATTACHED] = "attached",
[USB_STATE_POWERED] = "powered",
[USB_STATE_RECONNECTING] = "reconnecting",
[USB_STATE_UNAUTHENTICATED] = "unauthenticated",
[USB_STATE_DEFAULT] = "default",
[USB_STATE_ADDRESS] = "addresssed",
[USB_STATE_CONFIGURED] = "configured",
[USB_STATE_SUSPENDED] = "suspended",
};
if (state < 0 || state >= ARRAY_SIZE(names))
return "UNKNOWN";
return names[state];
}
EXPORT_SYMBOL_GPL(usb_state_string);
#ifdef CONFIG_OF
static const char *const usb_dr_modes[] = {
[USB_DR_MODE_UNKNOWN] = "",
[USB_DR_MODE_HOST] = "host",
[USB_DR_MODE_PERIPHERAL] = "peripheral",
[USB_DR_MODE_OTG] = "otg",
};
/**
* of_usb_get_dr_mode - Get dual role mode for given device_node
* @np: Pointer to the given device_node
*
* The function gets phy interface string from property 'dr_mode',
* and returns the correspondig enum usb_dr_mode
*/
enum usb_dr_mode of_usb_get_dr_mode(struct device_node *np)
{
const char *dr_mode;
int err, i;
err = of_property_read_string(np, "dr_mode", &dr_mode);
if (err < 0)
return USB_DR_MODE_UNKNOWN;
for (i = 0; i < ARRAY_SIZE(usb_dr_modes); i++)
if (!strcmp(dr_mode, usb_dr_modes[i]))
return i;
return USB_DR_MODE_UNKNOWN;
}
EXPORT_SYMBOL_GPL(of_usb_get_dr_mode);
/**
* of_usb_get_maximum_speed - Get maximum requested speed for a given USB
* controller.
* @np: Pointer to the given device_node
*
* The function gets the maximum speed string from property "maximum-speed",
* and returns the corresponding enum usb_device_speed.
*/
enum usb_device_speed of_usb_get_maximum_speed(struct device_node *np)
{
const char *maximum_speed;
int err;
int i;
err = of_property_read_string(np, "maximum-speed", &maximum_speed);
if (err < 0)
return USB_SPEED_UNKNOWN;
for (i = 0; i < ARRAY_SIZE(speed_names); i++)
if (strcmp(maximum_speed, speed_names[i]) == 0)
return i;
return USB_SPEED_UNKNOWN;
}
EXPORT_SYMBOL_GPL(of_usb_get_maximum_speed);
#endif
MODULE_LICENSE("GPL");