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path: root/drivers/usb/common/usb-otg-fsm.c
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Diffstat (limited to 'drivers/usb/common/usb-otg-fsm.c')
-rw-r--r--drivers/usb/common/usb-otg-fsm.c367
1 files changed, 367 insertions, 0 deletions
diff --git a/drivers/usb/common/usb-otg-fsm.c b/drivers/usb/common/usb-otg-fsm.c
new file mode 100644
index 000000000..61d538aa2
--- /dev/null
+++ b/drivers/usb/common/usb-otg-fsm.c
@@ -0,0 +1,367 @@
+/*
+ * 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/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;
+}
+
+static int state_changed;
+
+/* 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:
+ 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;
+ 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 */
+static int otg_set_state(struct otg_fsm *fsm, enum usb_otg_state new_state)
+{
+ state_changed = 1;
+ 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);
+ 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);
+ 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;
+ return 0;
+}
+
+/* State change judgement */
+int otg_statemachine(struct otg_fsm *fsm)
+{
+ enum usb_otg_state state;
+
+ mutex_lock(&fsm->lock);
+
+ state = fsm->otg->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->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", state_changed);
+ return state_changed;
+}
+EXPORT_SYMBOL_GPL(otg_statemachine);
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-18 17:01:46 +0000