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Release 4.7 drivers/usb/common/usb-otg-fsm.c

/*
 * OTG Finite State Machine from OTG spec
 *
 * Copyright (C) 2007,2008 Freescale Semiconductor, Inc.
 *
 * Author:      Li Yang <LeoLi@freescale.com>
 *              Jerry Huang <Chang-Ming.Huang@freescale.com>
 *
 * 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;  either version 2 of the  License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the  GNU General Public License along
 * with this program; if not, write  to the Free Software Foundation, Inc.,
 * 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/delay.h>
#include <linux/usb.h>
#include <linux/usb/gadget.h>
#include <linux/usb/otg.h>
#include <linux/usb/otg-fsm.h>

/* Change USB protocol when there is a protocol change */

static int otg_set_protocol(struct otg_fsm *fsm, int protocol) { int ret = 0; if (fsm->protocol != protocol) { VDBG("Changing role fsm->protocol= %d; new protocol= %d\n", fsm->protocol, protocol); /* stop old protocol */ if (fsm->protocol == PROTO_HOST) ret = otg_start_host(fsm, 0); else if (fsm->protocol == PROTO_GADGET) ret = otg_start_gadget(fsm, 0); if (ret) return ret; /* start new protocol */ if (protocol == PROTO_HOST) ret = otg_start_host(fsm, 1); else if (protocol == PROTO_GADGET) ret = otg_start_gadget(fsm, 1); if (ret) return ret; fsm->protocol = protocol; return 0; } return 0; }

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PersonTokensPropCommitsCommitProp
li yangli yang13097.01%150.00%
anton tikhomirovanton tikhomirov42.99%150.00%
Total134100.00%2100.00%

/* Called when leaving a state. Do state clean up jobs here */
static void otg_leave_state(struct otg_fsm *fsm, enum usb_otg_state old_state) { switch (old_state) { case OTG_STATE_B_IDLE: otg_del_timer(fsm, B_SE0_SRP); fsm->b_se0_srp = 0; fsm->adp_sns = 0; fsm->adp_prb = 0; break; case OTG_STATE_B_SRP_INIT: fsm->data_pulse = 0; fsm->b_srp_done = 0; break; case OTG_STATE_B_PERIPHERAL: if (fsm->otg->gadget) fsm->otg->gadget->host_request_flag = 0; break; case OTG_STATE_B_WAIT_ACON: otg_del_timer(fsm, B_ASE0_BRST); fsm->b_ase0_brst_tmout = 0; break; case OTG_STATE_B_HOST: break; case OTG_STATE_A_IDLE: fsm->adp_prb = 0; break; case OTG_STATE_A_WAIT_VRISE: otg_del_timer(fsm, A_WAIT_VRISE); fsm->a_wait_vrise_tmout = 0; break; case OTG_STATE_A_WAIT_BCON: otg_del_timer(fsm, A_WAIT_BCON); fsm->a_wait_bcon_tmout = 0; break; case OTG_STATE_A_HOST: otg_del_timer(fsm, A_WAIT_ENUM); break; case OTG_STATE_A_SUSPEND: otg_del_timer(fsm, A_AIDL_BDIS); fsm->a_aidl_bdis_tmout = 0; fsm->a_suspend_req_inf = 0; break; case OTG_STATE_A_PERIPHERAL: otg_del_timer(fsm, A_BIDL_ADIS); fsm->a_bidl_adis_tmout = 0; if (fsm->otg->gadget) fsm->otg->gadget->host_request_flag = 0; break; case OTG_STATE_A_WAIT_VFALL: otg_del_timer(fsm, A_WAIT_VFALL); fsm->a_wait_vfall_tmout = 0; otg_del_timer(fsm, A_WAIT_VRISE); break; case OTG_STATE_A_VBUS_ERR: break; default: break; } }

Contributors

PersonTokensPropCommitsCommitProp
li yangli yang15762.30%114.29%
anton tikhomirovanton tikhomirov5823.02%457.14%
li junli jun3614.29%114.29%
sachin kamatsachin kamat10.40%114.29%
Total252100.00%7100.00%


static void otg_hnp_polling_work(struct work_struct *work) { struct otg_fsm *fsm = container_of(to_delayed_work(work), struct otg_fsm, hnp_polling_work); struct usb_device *udev; enum usb_otg_state state = fsm->otg->state; u8 flag; int retval; if (state != OTG_STATE_A_HOST && state != OTG_STATE_B_HOST) return; udev = usb_hub_find_child(fsm->otg->host->root_hub, 1); if (!udev) { dev_err(fsm->otg->host->controller, "no usb dev connected, can't start HNP polling\n"); return; } *fsm->host_req_flag = 0; /* Get host request flag from connected USB device */ retval = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0), USB_REQ_GET_STATUS, USB_DIR_IN | USB_RECIP_DEVICE, 0, OTG_STS_SELECTOR, fsm->host_req_flag, 1, USB_CTRL_GET_TIMEOUT); if (retval != 1) { dev_err(&udev->dev, "Get one byte OTG status failed\n"); return; } flag = *fsm->host_req_flag; if (flag == 0) { /* Continue HNP polling */ schedule_delayed_work(&fsm->hnp_polling_work, msecs_to_jiffies(T_HOST_REQ_POLL)); return; } else if (flag != HOST_REQUEST_FLAG) { dev_err(&udev->dev, "host request flag %d is invalid\n", flag); return; } /* Host request flag is set */ if (state == OTG_STATE_A_HOST) { /* Set b_hnp_enable */ if (!fsm->otg->host->b_hnp_enable) { retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), USB_REQ_SET_FEATURE, 0, USB_DEVICE_B_HNP_ENABLE, 0, NULL, 0, USB_CTRL_SET_TIMEOUT); if (retval >= 0) fsm->otg->host->b_hnp_enable = 1; } fsm->a_bus_req = 0; } else if (state == OTG_STATE_B_HOST) { fsm->b_bus_req = 0; } otg_statemachine(fsm); }

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PersonTokensPropCommitsCommitProp
li junli jun301100.00%1100.00%
Total301100.00%1100.00%


static void otg_start_hnp_polling(struct otg_fsm *fsm) { /* * The memory of host_req_flag should be allocated by * controller driver, otherwise, hnp polling is not started. */ if (!fsm->host_req_flag) return; INIT_DELAYED_WORK(&fsm->hnp_polling_work, otg_hnp_polling_work); schedule_delayed_work(&fsm->hnp_polling_work, msecs_to_jiffies(T_HOST_REQ_POLL)); }

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PersonTokensPropCommitsCommitProp
li junli jun43100.00%1100.00%
Total43100.00%1100.00%

/* Called when entering a state */
static int otg_set_state(struct otg_fsm *fsm, enum usb_otg_state new_state) { if (fsm->otg->state == new_state) return 0; VDBG("Set state: %s\n", usb_otg_state_string(new_state)); otg_leave_state(fsm, fsm->otg->state); switch (new_state) { case OTG_STATE_B_IDLE: otg_drv_vbus(fsm, 0); otg_chrg_vbus(fsm, 0); otg_loc_conn(fsm, 0); otg_loc_sof(fsm, 0); /* * Driver is responsible for starting ADP probing * if ADP sensing times out. */ otg_start_adp_sns(fsm); otg_set_protocol(fsm, PROTO_UNDEF); otg_add_timer(fsm, B_SE0_SRP); break; case OTG_STATE_B_SRP_INIT: otg_start_pulse(fsm); otg_loc_sof(fsm, 0); otg_set_protocol(fsm, PROTO_UNDEF); otg_add_timer(fsm, B_SRP_FAIL); break; case OTG_STATE_B_PERIPHERAL: otg_chrg_vbus(fsm, 0); otg_loc_sof(fsm, 0); otg_set_protocol(fsm, PROTO_GADGET); otg_loc_conn(fsm, 1); break; case OTG_STATE_B_WAIT_ACON: otg_chrg_vbus(fsm, 0); otg_loc_conn(fsm, 0); otg_loc_sof(fsm, 0); otg_set_protocol(fsm, PROTO_HOST); otg_add_timer(fsm, B_ASE0_BRST); fsm->a_bus_suspend = 0; break; case OTG_STATE_B_HOST: otg_chrg_vbus(fsm, 0); otg_loc_conn(fsm, 0); otg_loc_sof(fsm, 1); otg_set_protocol(fsm, PROTO_HOST); usb_bus_start_enum(fsm->otg->host, fsm->otg->host->otg_port); otg_start_hnp_polling(fsm); break; case OTG_STATE_A_IDLE: otg_drv_vbus(fsm, 0); otg_chrg_vbus(fsm, 0); otg_loc_conn(fsm, 0); otg_loc_sof(fsm, 0); otg_start_adp_prb(fsm); otg_set_protocol(fsm, PROTO_HOST); break; case OTG_STATE_A_WAIT_VRISE: otg_drv_vbus(fsm, 1); otg_loc_conn(fsm, 0); otg_loc_sof(fsm, 0); otg_set_protocol(fsm, PROTO_HOST); otg_add_timer(fsm, A_WAIT_VRISE); break; case OTG_STATE_A_WAIT_BCON: otg_drv_vbus(fsm, 1); otg_loc_conn(fsm, 0); otg_loc_sof(fsm, 0); otg_set_protocol(fsm, PROTO_HOST); otg_add_timer(fsm, A_WAIT_BCON); break; case OTG_STATE_A_HOST: otg_drv_vbus(fsm, 1); otg_loc_conn(fsm, 0); otg_loc_sof(fsm, 1); otg_set_protocol(fsm, PROTO_HOST); /* * When HNP is triggered while a_bus_req = 0, a_host will * suspend too fast to complete a_set_b_hnp_en */ if (!fsm->a_bus_req || fsm->a_suspend_req_inf) otg_add_timer(fsm, A_WAIT_ENUM); otg_start_hnp_polling(fsm); break; case OTG_STATE_A_SUSPEND: otg_drv_vbus(fsm, 1); otg_loc_conn(fsm, 0); otg_loc_sof(fsm, 0); otg_set_protocol(fsm, PROTO_HOST); otg_add_timer(fsm, A_AIDL_BDIS); break; case OTG_STATE_A_PERIPHERAL: otg_loc_sof(fsm, 0); otg_set_protocol(fsm, PROTO_GADGET); otg_drv_vbus(fsm, 1); otg_loc_conn(fsm, 1); otg_add_timer(fsm, A_BIDL_ADIS); break; case OTG_STATE_A_WAIT_VFALL: otg_drv_vbus(fsm, 0); otg_loc_conn(fsm, 0); otg_loc_sof(fsm, 0); otg_set_protocol(fsm, PROTO_HOST); otg_add_timer(fsm, A_WAIT_VFALL); break; case OTG_STATE_A_VBUS_ERR: otg_drv_vbus(fsm, 0); otg_loc_conn(fsm, 0); otg_loc_sof(fsm, 0); otg_set_protocol(fsm, PROTO_UNDEF); break; default: break; } fsm->otg->state = new_state; fsm->state_changed = 1; return 0; }

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PersonTokensPropCommitsCommitProp
li yangli yang54288.27%19.09%
anton tikhomirovanton tikhomirov335.37%436.36%
peter chenpeter chen132.12%19.09%
li junli jun101.63%19.09%
heikki krogerusheikki krogerus81.30%19.09%
roger quadrosroger quadros60.98%19.09%
sachin kamatsachin kamat10.16%19.09%
felipe balbifelipe balbi10.16%19.09%
Total614100.00%11100.00%

/* State change judgement */
int otg_statemachine(struct otg_fsm *fsm) { enum usb_otg_state state; mutex_lock(&fsm->lock); state = fsm->otg->state; fsm->state_changed = 0; /* State machine state change judgement */ switch (state) { case OTG_STATE_UNDEFINED: VDBG("fsm->id = %d\n", fsm->id); if (fsm->id) otg_set_state(fsm, OTG_STATE_B_IDLE); else otg_set_state(fsm, OTG_STATE_A_IDLE); break; case OTG_STATE_B_IDLE: if (!fsm->id) otg_set_state(fsm, OTG_STATE_A_IDLE); else if (fsm->b_sess_vld && fsm->otg->gadget) otg_set_state(fsm, OTG_STATE_B_PERIPHERAL); else if ((fsm->b_bus_req || fsm->adp_change || fsm->power_up) && fsm->b_ssend_srp && fsm->b_se0_srp) otg_set_state(fsm, OTG_STATE_B_SRP_INIT); break; case OTG_STATE_B_SRP_INIT: if (!fsm->id || fsm->b_srp_done) otg_set_state(fsm, OTG_STATE_B_IDLE); break; case OTG_STATE_B_PERIPHERAL: if (!fsm->id || !fsm->b_sess_vld) otg_set_state(fsm, OTG_STATE_B_IDLE); else if (fsm->b_bus_req && fsm->otg-> gadget->b_hnp_enable && fsm->a_bus_suspend) otg_set_state(fsm, OTG_STATE_B_WAIT_ACON); break; case OTG_STATE_B_WAIT_ACON: if (fsm->a_conn) otg_set_state(fsm, OTG_STATE_B_HOST); else if (!fsm->id || !fsm->b_sess_vld) otg_set_state(fsm, OTG_STATE_B_IDLE); else if (fsm->a_bus_resume || fsm->b_ase0_brst_tmout) { fsm->b_ase0_brst_tmout = 0; otg_set_state(fsm, OTG_STATE_B_PERIPHERAL); } break; case OTG_STATE_B_HOST: if (!fsm->id || !fsm->b_sess_vld) otg_set_state(fsm, OTG_STATE_B_IDLE); else if (!fsm->b_bus_req || !fsm->a_conn || fsm->test_device) otg_set_state(fsm, OTG_STATE_B_PERIPHERAL); break; case OTG_STATE_A_IDLE: if (fsm->id) otg_set_state(fsm, OTG_STATE_B_IDLE); else if (!fsm->a_bus_drop && (fsm->a_bus_req || fsm->a_srp_det || fsm->adp_change || fsm->power_up)) otg_set_state(fsm, OTG_STATE_A_WAIT_VRISE); break; case OTG_STATE_A_WAIT_VRISE: if (fsm->a_vbus_vld) otg_set_state(fsm, OTG_STATE_A_WAIT_BCON); else if (fsm->id || fsm->a_bus_drop || fsm->a_wait_vrise_tmout) otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL); break; case OTG_STATE_A_WAIT_BCON: if (!fsm->a_vbus_vld) otg_set_state(fsm, OTG_STATE_A_VBUS_ERR); else if (fsm->b_conn) otg_set_state(fsm, OTG_STATE_A_HOST); else if (fsm->id || fsm->a_bus_drop || fsm->a_wait_bcon_tmout) otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL); break; case OTG_STATE_A_HOST: if (fsm->id || fsm->a_bus_drop) otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL); else if ((!fsm->a_bus_req || fsm->a_suspend_req_inf) && fsm->otg->host->b_hnp_enable) otg_set_state(fsm, OTG_STATE_A_SUSPEND); else if (!fsm->b_conn) otg_set_state(fsm, OTG_STATE_A_WAIT_BCON); else if (!fsm->a_vbus_vld) otg_set_state(fsm, OTG_STATE_A_VBUS_ERR); break; case OTG_STATE_A_SUSPEND: if (!fsm->b_conn && fsm->otg->host->b_hnp_enable) otg_set_state(fsm, OTG_STATE_A_PERIPHERAL); else if (!fsm->b_conn && !fsm->otg->host->b_hnp_enable) otg_set_state(fsm, OTG_STATE_A_WAIT_BCON); else if (fsm->a_bus_req || fsm->b_bus_resume) otg_set_state(fsm, OTG_STATE_A_HOST); else if (fsm->id || fsm->a_bus_drop || fsm->a_aidl_bdis_tmout) otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL); else if (!fsm->a_vbus_vld) otg_set_state(fsm, OTG_STATE_A_VBUS_ERR); break; case OTG_STATE_A_PERIPHERAL: if (fsm->id || fsm->a_bus_drop) otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL); else if (fsm->a_bidl_adis_tmout || fsm->b_bus_suspend) otg_set_state(fsm, OTG_STATE_A_WAIT_BCON); else if (!fsm->a_vbus_vld) otg_set_state(fsm, OTG_STATE_A_VBUS_ERR); break; case OTG_STATE_A_WAIT_VFALL: if (fsm->a_wait_vfall_tmout) otg_set_state(fsm, OTG_STATE_A_IDLE); break; case OTG_STATE_A_VBUS_ERR: if (fsm->id || fsm->a_bus_drop || fsm->a_clr_err) otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL); break; default: break; } mutex_unlock(&fsm->lock); VDBG("quit statemachine, changed = %d\n", fsm->state_changed); return fsm->state_changed; }

Contributors

PersonTokensPropCommitsCommitProp
li yangli yang69789.82%18.33%
li junli jun334.25%216.67%
anton tikhomirovanton tikhomirov313.99%650.00%
heikki krogerusheikki krogerus70.90%18.33%
roger quadrosroger quadros60.77%18.33%
peter chenpeter chen20.26%18.33%
Total776100.00%12100.00%

EXPORT_SYMBOL_GPL(otg_statemachine); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
li yangli yang155371.83%14.76%
li junli jun42819.80%419.05%
anton tikhomirovanton tikhomirov1285.92%942.86%
heikki krogerusheikki krogerus150.69%14.76%
peter chenpeter chen150.69%29.52%
roger quadrosroger quadros120.56%14.76%
oscar at naiandei.netoscar at naiandei.net80.37%14.76%
sachin kamatsachin kamat20.09%14.76%
felipe balbifelipe balbi10.05%14.76%
Total2162100.00%21100.00%
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