diff options
Diffstat (limited to 'drivers/usb/otg/otg_fsm.c')
-rw-r--r-- | drivers/usb/otg/otg_fsm.c | 349 |
1 files changed, 349 insertions, 0 deletions
diff --git a/drivers/usb/otg/otg_fsm.c b/drivers/usb/otg/otg_fsm.c new file mode 100644 index 00000000000..b0cc422f2ff --- /dev/null +++ b/drivers/usb/otg/otg_fsm.c @@ -0,0 +1,349 @@ +/* + * 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 <linux/types.h> + +#include "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 = fsm->ops->start_host(fsm, 0); + else if (fsm->protocol == PROTO_GADGET) + ret = fsm->ops->start_gadget(fsm, 0); + if (ret) + return ret; + + /* start new protocol */ + if (protocol == PROTO_HOST) + ret = fsm->ops->start_host(fsm, 1); + else if (protocol == PROTO_GADGET) + ret = fsm->ops->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_tmr); + 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_tmr); + 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_tmr); + fsm->a_wait_vrise_tmout = 0; + break; + case OTG_STATE_A_WAIT_BCON: + otg_del_timer(fsm, a_wait_bcon_tmr); + fsm->a_wait_bcon_tmout = 0; + break; + case OTG_STATE_A_HOST: + otg_del_timer(fsm, a_wait_enum_tmr); + break; + case OTG_STATE_A_SUSPEND: + otg_del_timer(fsm, a_aidl_bdis_tmr); + fsm->a_aidl_bdis_tmout = 0; + fsm->a_suspend_req = 0; + break; + case OTG_STATE_A_PERIPHERAL: + break; + case OTG_STATE_A_WAIT_VFALL: + otg_del_timer(fsm, a_wait_vrise_tmr); + 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->transceiver->state == new_state) + return 0; + VDBG("Set state: %s\n", otg_state_string(new_state)); + otg_leave_state(fsm, fsm->transceiver->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_tmr); + 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_tmr); + 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_tmr); + 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->transceiver->host, + fsm->transceiver->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_tmr); + 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_tmr); + 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) + otg_add_timer(fsm, a_wait_enum_tmr); + 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_tmr); + + 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); + 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); + 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->transceiver->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->transceiver->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->transceiver->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->transceiver-> + 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) && + fsm->transceiver->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->transceiver->host->b_hnp_enable) + otg_set_state(fsm, OTG_STATE_A_PERIPHERAL); + else if (!fsm->b_conn && !fsm->transceiver->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->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->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; +} |