| /* |
| * 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/kernel.h> |
| #include <linux/types.h> |
| #include <linux/spinlock.h> |
| #include <linux/delay.h> |
| #include <linux/usb.h> |
| #include <linux/usb/gadget.h> |
| #include <linux/usb/otg.h> |
| |
| #include "phy-fsm-usb.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; |
| } |
| |
| static int state_changed; |
| |
| /* Called when leaving a state. Do state clean up jobs here */ |
| 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; |
| break; |
| case OTG_STATE_B_SRP_INIT: |
| fsm->b_srp_done = 0; |
| break; |
| case OTG_STATE_B_PERIPHERAL: |
| 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: |
| 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; |
| 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; |
| } |
| } |
| |
| /* Called when entering a state */ |
| int otg_set_state(struct otg_fsm *fsm, enum usb_otg_state new_state) |
| { |
| state_changed = 1; |
| if (fsm->otg->phy->state == new_state) |
| return 0; |
| VDBG("Set state: %s\n", usb_otg_state_string(new_state)); |
| otg_leave_state(fsm, fsm->otg->phy->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); |
| 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_conn(fsm, 1); |
| otg_loc_sof(fsm, 0); |
| otg_set_protocol(fsm, PROTO_GADGET); |
| 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); |
| 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_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); |
| 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_conn(fsm, 1); |
| otg_loc_sof(fsm, 0); |
| otg_set_protocol(fsm, PROTO_GADGET); |
| otg_drv_vbus(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->phy->state = new_state; |
| return 0; |
| } |
| |
| /* State change judgement */ |
| int otg_statemachine(struct otg_fsm *fsm) |
| { |
| enum usb_otg_state state; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&fsm->lock, flags); |
| |
| state = fsm->otg->phy->state; |
| 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->b_sess_end && 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) |
| 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)) |
| otg_set_state(fsm, OTG_STATE_A_WAIT_VRISE); |
| break; |
| case OTG_STATE_A_WAIT_VRISE: |
| if (fsm->id || fsm->a_bus_drop || fsm->a_vbus_vld || |
| fsm->a_wait_vrise_tmout) { |
| otg_set_state(fsm, OTG_STATE_A_WAIT_BCON); |
| } |
| 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->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->id || !fsm->b_conn || fsm->a_bus_drop) |
| 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 || fsm->id || fsm->a_bus_req || |
| (!fsm->a_sess_vld && !fsm->b_conn)) |
| 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; |
| } |
| spin_unlock_irqrestore(&fsm->lock, flags); |
| |
| VDBG("quit statemachine, changed = %d\n", state_changed); |
| return state_changed; |
| } |