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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/usb/common/usb-otg-fsm.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--drivers/usb/common/usb-otg-fsm.c452
1 files changed, 452 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..0697fde51
--- /dev/null
+++ b/drivers/usb/common/usb-otg-fsm.c
@@ -0,0 +1,452 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * 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>
+ */
+
+#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>
+
+#ifdef VERBOSE
+#define VDBG(fmt, args...) pr_debug("[%s] " fmt, \
+ __func__, ## args)
+#else
+#define VDBG(stuff...) do {} while (0)
+#endif
+
+/* 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;
+}
+
+/* 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;
+ }
+}
+
+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);
+}
+
+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;
+
+ if (!fsm->hnp_work_inited) {
+ INIT_DELAYED_WORK(&fsm->hnp_polling_work, otg_hnp_polling_work);
+ fsm->hnp_work_inited = true;
+ }
+
+ schedule_delayed_work(&fsm->hnp_polling_work,
+ msecs_to_jiffies(T_HOST_REQ_POLL));
+}
+
+/* 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;
+}
+
+/* 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;
+}
+EXPORT_SYMBOL_GPL(otg_statemachine);
+MODULE_LICENSE("GPL");