On Mon, Mar 31, 2014 at 03:24:35PM +0800, Peter Chen wrote:
> On Sun, Mar 30, 2014 at 08:20:09PM +0800, Li Jun wrote:
> > From: Li Jun <b47624@xxxxxxxxxxxxx>
> >
> > USB OTG interrupt handling and fsm transitions according to USB OTG
> > and EH 2.0.
> >
> > Signed-off-by: Li Jun <b47624@xxxxxxxxxxxxx>
> > ---
> > drivers/usb/chipidea/core.c | 8 +-
> > drivers/usb/chipidea/otg.c | 9 +-
> > drivers/usb/chipidea/otg_fsm.c | 236 ++++++++++++++++++++++++++++++++++++++++
> > drivers/usb/chipidea/otg_fsm.h | 18 +++
> > drivers/usb/chipidea/udc.c | 6 +
> > 5 files changed, 273 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
> > index ff38cf3..6544149 100644
> > --- a/drivers/usb/chipidea/core.c
> > +++ b/drivers/usb/chipidea/core.c
> > @@ -42,7 +42,6 @@
> > * - Not Supported: 15 & 16 (ISO)
> > *
> > * TODO List
> > - * - OTG
> > * - Interrupt Traffic
> > * - GET_STATUS(device) - always reports 0
> > * - Gadget API (majority of optional features)
> > @@ -74,6 +73,7 @@
> > #include "host.h"
> > #include "debug.h"
> > #include "otg.h"
> > +#include "otg_fsm.h"
> >
> > /* Controller register map */
> > static const u8 ci_regs_nolpm[] = {
> > @@ -412,8 +412,12 @@ static irqreturn_t ci_irq(int irq, void *data)
> > irqreturn_t ret = IRQ_NONE;
> > u32 otgsc = 0;
> >
> > - if (ci->is_otg)
> > + if (ci->is_otg) {
> > otgsc = hw_read_otgsc(ci, ~0);
> > + ret = ci_otg_fsm_irq(ci);
> > + if (ret == IRQ_HANDLED)
> > + return ret;
> > + }
> >
> > /*
> > * Handle id change interrupt, it indicates device/host function
> > diff --git a/drivers/usb/chipidea/otg.c b/drivers/usb/chipidea/otg.c
> > index b278cd9..5169640 100644
> > --- a/drivers/usb/chipidea/otg.c
> > +++ b/drivers/usb/chipidea/otg.c
> > @@ -11,8 +11,8 @@
> > */
> >
> > /*
> > - * This file mainly handles otgsc register, it may include OTG operation
> > - * in the future.
> > + * This file mainly handles otgsc register, OTG fsm operations for HNP and SRP
> > + * are also included.
> > */
> >
> > #include <linux/usb/otg.h>
> > @@ -91,6 +91,11 @@ static void ci_otg_work(struct work_struct *work)
> > {
> > struct ci_hdrc *ci = container_of(work, struct ci_hdrc, work);
> >
> > + if (!ci_otg_fsm_work(ci)) {
> > + enable_irq(ci->irq);
> > + return;
> > + }
> > +
> > if (ci->id_event) {
> > ci->id_event = false;
> > ci_handle_id_switch(ci);
> > diff --git a/drivers/usb/chipidea/otg_fsm.c b/drivers/usb/chipidea/otg_fsm.c
> > index d49bbdd..8e30fc64 100644
> > --- a/drivers/usb/chipidea/otg_fsm.c
> > +++ b/drivers/usb/chipidea/otg_fsm.c
> > @@ -13,6 +13,10 @@
> > /*
> > * This file mainly handles OTG fsm, it includes OTG fsm operations
> > * for HNP and SRP.
> > + *
> > + * TODO List
> > + * - ADP
> > + * - OTG test device
> > */
> >
> > #include <linux/usb/otg.h>
> > @@ -92,6 +96,33 @@ static void ci_otg_del_timer(struct ci_hdrc *ci, enum ci_otg_fsm_timer_index t)
> > hw_write_otgsc(ci, OTGSC_1MSIE, 0);
> > }
> >
> > +/*
> > + * Reduce timer count by 1, and find timeout conditions.
> > + * Called by otg 1ms timer interrupt
> > + */
> > +static inline int ci_otg_tick_timer(struct ci_hdrc *ci)
> > +{
> > + struct ci_otg_fsm_timer *tmp_timer, *del_tmp;
> > + struct list_head *active_timers = &ci->fsm_timer->active_timers;
> > + int expired = 0;
> > +
> > + list_for_each_entry_safe(tmp_timer, del_tmp, active_timers, list) {
> > + tmp_timer->count--;
> > + /* check if timer expires */
> > + if (!tmp_timer->count) {
> > + list_del(&tmp_timer->list);
> > + tmp_timer->function(ci, tmp_timer->data);
> > + expired = 1;
> > + }
> > + }
> > +
> > + /* disable 1ms irq if there is no any timer active */
> > + if ((expired == 1) && list_empty(active_timers))
> > + hw_write_otgsc(ci, OTGSC_1MSIE, 0);
> > +
> > + return expired;
> > +}
> > +
> > /* The timeout callback function to set time out bit */
> > static void set_tmout(void *ptr, unsigned long indicator)
> > {
> > @@ -385,6 +416,209 @@ static struct otg_fsm_ops ci_otg_ops = {
> > .start_gadget = ci_otg_start_gadget,
> > };
> >
> > +int ci_otg_fsm_work(struct ci_hdrc *ci)
> > +{
> > + if (!ci->transceiver->otg)
> > + return -ENODEV;
> > +
> > + /*
> > + * Don't do fsm transition for B device
> > + * when there is no gadget class driver
> > + */
> > + if (ci->fsm.id && !(ci->driver) &&
> > + ci->transceiver->state < OTG_STATE_A_IDLE)
>
> Why the third condition is needed?
>
To make a_xxxx state can be transfered to next state when micro-A plug is removed
(id is 1) while gadget driver is not enabled.
> > + return 0;
> > +
> > + if (otg_statemachine(&ci->fsm)) {
> > + if (ci->transceiver->state == OTG_STATE_A_IDLE) {
> > + if (ci->fsm.id)
> > + /* A idle to B idle */
> > + otg_statemachine(&ci->fsm);
> > + else if ((ci->id_event) || (ci->fsm.power_up)) {
> > + ci->id_event = false;
> > + /* A idle to A wait vrise */
> > + otg_statemachine(&ci->fsm);
> > + ci->fsm.power_up = false;
> > + }
> > + }
> > + }
> > + return 0;
> > +}
> > +
> > +/*
> > + * Update fsm variables in each state if catching expected interrupts,
> > + * called by otg fsm isr.
> > + */
> > +static void ci_otg_fsm_event(struct ci_hdrc *ci)
> > +{
> > + u32 intr_sts, otg_bsess_vld, port_conn;
> > + struct otg_fsm *fsm = &ci->fsm;
> > +
> > + intr_sts = hw_read_intr_status(ci);
> > + otg_bsess_vld = hw_read_otgsc(ci, OTGSC_BSV);
> > + port_conn = hw_read(ci, OP_PORTSC, PORTSC_CCS);
> > +
> > + switch (ci->transceiver->state) {
> > + case OTG_STATE_A_WAIT_BCON:
> > + if (port_conn) {
> > + fsm->b_conn = 1;
> > + fsm->a_bus_req = 1;
> > + disable_irq_nosync(ci->irq);
> > + queue_work(ci->wq, &ci->work);
> > + }
> > + break;
> > + case OTG_STATE_B_IDLE:
> > + if (otg_bsess_vld && (intr_sts & USBi_PCI) && port_conn) {
> > + fsm->b_sess_vld = 1;
> > + if (fsm->power_up)
> > + fsm->power_up = 0;
> > + disable_irq_nosync(ci->irq);
> > + queue_work(ci->wq, &ci->work);
> > + }
> > + break;
> > + case OTG_STATE_B_PERIPHERAL:
> > + if ((intr_sts & USBi_SLI) && port_conn && otg_bsess_vld) {
> > + fsm->a_bus_suspend = 1;
> > + disable_irq_nosync(ci->irq);
> > + queue_work(ci->wq, &ci->work);
> > + } else if (intr_sts & USBi_PCI) {
> > + if (fsm->a_bus_suspend == 1)
> > + fsm->a_bus_suspend = 0;
> > + }
> > + break;
> > + case OTG_STATE_B_HOST:
> > + if ((intr_sts & USBi_PCI) && !port_conn) {
> > + fsm->a_conn = 0;
> > + fsm->b_bus_req = 0;
> > + disable_irq_nosync(ci->irq);
> > + queue_work(ci->wq, &ci->work);
> > + ci_otg_add_timer(ci, B_SESS_VLD);
> > + }
> > + break;
> > + case OTG_STATE_A_PERIPHERAL:
> > + if (intr_sts & USBi_SLI) {
> > + fsm->b_bus_suspend = 1;
> > + /*
> > + * Init a timer to know how long this suspend
> > + * will contine, if time out, indicates B no longer
> > + * wants to be host role
> > + */
> > + ci_otg_add_timer(ci, A_BIDL_ADIS);
> > + }
> > +
> > + if (intr_sts & USBi_URI)
> > + ci_otg_del_timer(ci, A_BIDL_ADIS);
> > +
> > + if (intr_sts & USBi_PCI) {
> > + if (fsm->b_bus_suspend == 1) {
> > + ci_otg_del_timer(ci, A_BIDL_ADIS);
> > + fsm->b_bus_suspend = 0;
> > + }
> > + }
> > + break;
> > + case OTG_STATE_A_SUSPEND:
> > + if ((intr_sts & USBi_PCI) && !port_conn) {
> > + fsm->b_conn = 0;
> > +
> > + /* if gadget driver is binded */
> > + if (ci->driver) {
> > + /* A device to be peripheral mode */
> > + ci->gadget.is_a_peripheral = 1;
> > + }
> > + disable_irq_nosync(ci->irq);
> > + queue_work(ci->wq, &ci->work);
> > + }
> > + break;
> > + case OTG_STATE_A_HOST:
> > + if ((intr_sts & USBi_PCI) && !port_conn) {
> > + fsm->b_conn = 0;
> > + disable_irq_nosync(ci->irq);
> > + queue_work(ci->wq, &ci->work);
> > + }
> > + break;
> > + case OTG_STATE_B_WAIT_ACON:
> > + if ((intr_sts & USBi_PCI) && port_conn) {
> > + fsm->a_conn = 1;
> > + disable_irq_nosync(ci->irq);
> > + queue_work(ci->wq, &ci->work);
> > + }
> > + break;
> > + default:
> > + break;
> > + }
> > +}
> > +
> > +/*
> > + * ci_otg_irq - otg fsm related irq handling
> > + * and also update otg fsm variable by monitoring usb host and udc
> > + * state change interrupts.
> > + * @ci: ci_hdrc
> > + */
> > +irqreturn_t ci_otg_fsm_irq(struct ci_hdrc *ci)
> > +{
> > + irqreturn_t retval = IRQ_NONE;
> > + u32 otgsc, otg_int_src = 0;
> > + struct otg_fsm *fsm = &ci->fsm;
> > +
> > + if (!ci_otg_is_fsm_mode(ci))
> > + return retval;
> > +
> > + otgsc = hw_read_otgsc(ci, ~0);
> > + otg_int_src = otgsc & OTGSC_INT_STATUS_BITS & (otgsc >> 8);
> > + fsm->id = (otgsc & OTGSC_ID) ? 1 : 0;
> > +
> > + if (otg_int_src) {
> > + if (otg_int_src & OTGSC_1MSIS) {
> > + hw_write_otgsc(ci, OTGSC_1MSIS, OTGSC_1MSIS);
> > + retval = ci_otg_tick_timer(ci);
> > + return IRQ_HANDLED;
> > + } else if (otg_int_src & OTGSC_DPIS) {
> > + hw_write_otgsc(ci, OTGSC_DPIS, OTGSC_DPIS);
> > + fsm->a_srp_det = 1;
> > + fsm->a_bus_drop = 0;
> > + } else if (otg_int_src & OTGSC_IDIS) {
> > + hw_write_otgsc(ci, OTGSC_IDIS, OTGSC_IDIS);
> > + if (fsm->id == 0) {
> > + fsm->a_bus_req = 1;
> > + ci->id_event = true;
> > + }
> > + } else if (otg_int_src & OTGSC_BSVIS) {
> > + hw_write_otgsc(ci, OTGSC_BSVIS, OTGSC_BSVIS);
> > + if (otgsc & OTGSC_BSV) {
> > + fsm->b_sess_vld = 1;
> > + ci_otg_del_timer(ci, B_SSEND_SRP);
> > + ci_otg_del_timer(ci, B_SRP_FAIL);
> > + fsm->b_ssend_srp = 0;
> > + } else {
> > + fsm->b_sess_vld = 0;
> > + if (fsm->id)
> > + ci_otg_add_timer(ci, B_SSEND_SRP);
> > + }
> > + } else if (otg_int_src & OTGSC_AVVIS) {
> > + hw_write_otgsc(ci, OTGSC_AVVIS, OTGSC_AVVIS);
> > + if (otgsc & OTGSC_AVV) {
> > + fsm->a_vbus_vld = 1;
> > + } else {
> > + fsm->a_vbus_vld = 0;
> > + fsm->b_conn = 0;
> > + }
> > + }
> > + disable_irq_nosync(ci->irq);
> > + queue_work(ci->wq, &ci->work);
> > + return IRQ_HANDLED;
> > + }
> > +
> > + ci_otg_fsm_event(ci);
> > +
> > + return retval;
> > +}
> > +
> > +void ci_hdrc_otg_fsm_start(struct ci_hdrc *ci)
> > +{
> > + if (ci_otg_is_fsm_mode(ci))
> > + ci_otg_fsm_work(ci);
> > +}
> > +
> > int ci_hdrc_otg_fsm_init(struct ci_hdrc *ci)
> > {
> > int retval = 0;
> > @@ -435,5 +669,7 @@ int ci_hdrc_otg_fsm_init(struct ci_hdrc *ci)
> > hw_read_otgsc(ci, OTGSC_BSV) ? 1 : 0;
> > }
> >
> > + ci_hdrc_otg_fsm_start(ci);
> > +
>
> After this change, ci_hdrc_otg_fsm_start will be called before
> ci_role_start, is it your expectation?
>
It's no problem, here we just need drive the fsm from *null* state to some
known state, then further state transitions can be driven by irq/events.
> Besides, in order to avoid calling ci_hdrc_otg_fsm_start two times at
> peripheral mode, it is better move it to host_start, like you change for
> udc.c
>
host_start is not fit since it will be called in every gadget-->host
role switch, ci_hdrc_otg_fsm_start() only need be called once after power up.
> > return 0;
> > }
> > diff --git a/drivers/usb/chipidea/otg_fsm.h b/drivers/usb/chipidea/otg_fsm.h
> > index 5401775..661bf16 100644
> > --- a/drivers/usb/chipidea/otg_fsm.h
> > +++ b/drivers/usb/chipidea/otg_fsm.h
> > @@ -87,6 +87,9 @@ struct ci_otg_fsm_timer_list {
> > #ifdef CONFIG_USB_OTG_FSM
> >
> > int ci_hdrc_otg_fsm_init(struct ci_hdrc *ci);
> > +int ci_otg_fsm_work(struct ci_hdrc *ci);
> > +irqreturn_t ci_otg_fsm_irq(struct ci_hdrc *ci);
> > +void ci_hdrc_otg_fsm_start(struct ci_hdrc *ci);
> >
> > #else
> >
> > @@ -95,6 +98,21 @@ static inline int ci_hdrc_otg_fsm_init(struct ci_hdrc *ci)
> > return 0;
> > }
> >
> > +static inline int ci_otg_fsm_work(struct ci_hdrc *ci)
> > +{
> > + return -ENXIO;
> > +}
> > +
> > +static inline irqreturn_t ci_otg_fsm_irq(struct ci_hdrc *ci)
> > +{
> > + return IRQ_NONE;
> > +}
> > +
> > +static inline void ci_hdrc_otg_fsm_start(struct ci_hdrc *ci)
> > +{
> > +
> > +}
> > +
> > #endif
> >
> > #endif /* __DRIVERS_USB_CHIPIDEA_OTG_FSM_H */
> > diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
> > index cba7fd6..f4501bd 100644
> > --- a/drivers/usb/chipidea/udc.c
> > +++ b/drivers/usb/chipidea/udc.c
> > @@ -28,6 +28,7 @@
> > #include "bits.h"
> > #include "debug.h"
> > #include "otg.h"
> > +#include "otg_fsm.h"
> >
> > /* control endpoint description */
> > static const struct usb_endpoint_descriptor
> > @@ -1645,6 +1646,11 @@ static int ci_udc_start(struct usb_gadget *gadget,
> >
> > ci->driver = driver;
> > pm_runtime_get_sync(&ci->gadget.dev);
> > +
> > + /* Start otg fsm for B-device */
> > + if (ci->fsm.id == 1)
> > + ci_hdrc_otg_fsm_start(ci);
> > +
> > if (ci->vbus_active) {
> > spin_lock_irqsave(&ci->lock, flags);
> > hw_device_reset(ci, USBMODE_CM_DC);
> > --
> > 1.7.9.5
> >
> >
>
> --
>
> Best Regards,
> Peter Chen
>
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