USB: add Freescale USB OTG Transceiver driver

Slightly reworked and cleaned up driver from Freescale LTIB
for MPC5121E. The driver has been ported to the current kernel,
proc interface "/proc/driver/fsl_usb2_otg" has been replaced by
sysfs interface.
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/otg/Kconfig

@@ -122,4 +122,12 @@ config AB8500_USB
           This transceiver supports high and full speed devices plus,
           in host mode, low speed.
 
+config FSL_USB2_OTG
+	bool "Freescale USB OTG Transceiver Driver"
+	depends on USB_EHCI_FSL && USB_GADGET_FSL_USB2
+	select USB_OTG
+	select USB_OTG_UTILS
+	help
+	  Enable this to support Freescale USB OTG transceiver.
+
 endif # USB || OTG

drivers/usb/otg/Makefile

@@ -19,3 +19,5 @@ obj-$(CONFIG_USB_ULPI)		+= ulpi.o
 obj-$(CONFIG_USB_ULPI_VIEWPORT)	+= ulpi_viewport.o
 obj-$(CONFIG_USB_MSM_OTG)	+= msm_otg.o
 obj-$(CONFIG_AB8500_USB)	+= ab8500-usb.o
+fsl_usb2_otg-objs		:= fsl_otg.o otg_fsm.o
+obj-$(CONFIG_FSL_USB2_OTG)	+= fsl_usb2_otg.o

drivers/usb/otg/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/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;
+}

drivers/usb/otg/otg_fsm.h

+/* Copyright (C) 2007,2008 Freescale Semiconductor, Inc.
+ *
+ * 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.
+ */
+
+#undef DEBUG
+#undef VERBOSE
+
+#ifdef DEBUG
+#define DBG(fmt, args...) printk(KERN_DEBUG "[%s]  " fmt , \
+				 __func__, ## args)
+#else
+#define DBG(fmt, args...)	do {} while (0)
+#endif
+
+#ifdef VERBOSE
+#define VDBG		DBG
+#else
+#define VDBG(stuff...)	do {} while (0)
+#endif
+
+#ifdef VERBOSE
+#define MPC_LOC printk("Current Location [%s]:[%d]\n", __FILE__, __LINE__)
+#else
+#define MPC_LOC do {} while (0)
+#endif
+
+#define PROTO_UNDEF	(0)
+#define PROTO_HOST	(1)
+#define PROTO_GADGET	(2)
+
+/* OTG state machine according to the OTG spec */
+struct otg_fsm {
+	/* Input */
+	int a_bus_resume;
+	int a_bus_suspend;
+	int a_conn;
+	int a_sess_vld;
+	int a_srp_det;
+	int a_vbus_vld;
+	int b_bus_resume;
+	int b_bus_suspend;
+	int b_conn;
+	int b_se0_srp;
+	int b_sess_end;
+	int b_sess_vld;
+	int id;
+
+	/* Internal variables */
+	int a_set_b_hnp_en;
+	int b_srp_done;
+	int b_hnp_enable;
+
+	/* Timeout indicator for timers */
+	int a_wait_vrise_tmout;
+	int a_wait_bcon_tmout;
+	int a_aidl_bdis_tmout;
+	int b_ase0_brst_tmout;
+
+	/* Informative variables */
+	int a_bus_drop;
+	int a_bus_req;
+	int a_clr_err;
+	int a_suspend_req;
+	int b_bus_req;
+
+	/* Output */
+	int drv_vbus;
+	int loc_conn;
+	int loc_sof;
+
+	struct otg_fsm_ops *ops;
+	struct otg_transceiver *transceiver;
+
+	/* Current usb protocol used: 0:undefine; 1:host; 2:client */
+	int protocol;
+	spinlock_t lock;
+};
+
+struct otg_fsm_ops {
+	void	(*chrg_vbus)(int on);
+	void	(*drv_vbus)(int on);
+	void	(*loc_conn)(int on);
+	void	(*loc_sof)(int on);
+	void	(*start_pulse)(void);
+	void	(*add_timer)(void *timer);
+	void	(*del_timer)(void *timer);
+	int	(*start_host)(struct otg_fsm *fsm, int on);
+	int	(*start_gadget)(struct otg_fsm *fsm, int on);
+};
+
+
+static inline void otg_chrg_vbus(struct otg_fsm *fsm, int on)
+{
+	fsm->ops->chrg_vbus(on);
+}
+
+static inline void otg_drv_vbus(struct otg_fsm *fsm, int on)
+{
+	if (fsm->drv_vbus != on) {
+		fsm->drv_vbus = on;
+		fsm->ops->drv_vbus(on);
+	}
+}
+
+static inline void otg_loc_conn(struct otg_fsm *fsm, int on)
+{
+	if (fsm->loc_conn != on) {
+		fsm->loc_conn = on;
+		fsm->ops->loc_conn(on);
+	}
+}
+
+static inline void otg_loc_sof(struct otg_fsm *fsm, int on)
+{
+	if (fsm->loc_sof != on) {
+		fsm->loc_sof = on;
+		fsm->ops->loc_sof(on);
+	}
+}
+
+static inline void otg_start_pulse(struct otg_fsm *fsm)
+{
+	fsm->ops->start_pulse();
+}
+
+static inline void otg_add_timer(struct otg_fsm *fsm, void *timer)
+{
+	fsm->ops->add_timer(timer);
+}
+
+static inline void otg_del_timer(struct otg_fsm *fsm, void *timer)
+{
+	fsm->ops->del_timer(timer);
+}
+
+int otg_statemachine(struct otg_fsm *fsm);
+
+/* Defined by device specific driver, for different timer implementation */
+extern struct fsl_otg_timer *a_wait_vrise_tmr, *a_wait_bcon_tmr,
+	*a_aidl_bdis_tmr, *b_ase0_brst_tmr, *b_se0_srp_tmr, *b_srp_fail_tmr,
+	*a_wait_enum_tmr;