diff options
| -rw-r--r-- | drivers/usb/gadget/f_acm.c | 194 | ||||
| -rw-r--r-- | drivers/usb/gadget/u_serial.c | 56 | ||||
| -rw-r--r-- | drivers/usb/gadget/u_serial.h | 12 |
3 files changed, 235 insertions, 27 deletions
diff --git a/drivers/usb/gadget/f_acm.c b/drivers/usb/gadget/f_acm.c index f3bf561..5ee1590 100644 --- a/drivers/usb/gadget/f_acm.c +++ b/drivers/usb/gadget/f_acm.c @@ -47,16 +47,37 @@ struct f_acm { u8 ctrl_id, data_id; u8 port_num; + u8 pending; + + /* lock is mostly for pending and notify_req ... they get accessed + * by callbacks both from tty (open/close/break) under its spinlock, + * and notify_req.complete() which can't use that lock. + */ + spinlock_t lock; + struct acm_ep_descs fs; struct acm_ep_descs hs; struct usb_ep *notify; struct usb_endpoint_descriptor *notify_desc; + struct usb_request *notify_req; struct usb_cdc_line_coding port_line_coding; /* 8-N-1 etc */ + + /* SetControlLineState request -- CDC 1.1 section 6.2.14 (INPUT) */ u16 port_handshake_bits; -#define RS232_RTS (1 << 1) /* unused with full duplex */ -#define RS232_DTR (1 << 0) /* host is ready for data r/w */ +#define ACM_CTRL_RTS (1 << 1) /* unused with full duplex */ +#define ACM_CTRL_DTR (1 << 0) /* host is ready for data r/w */ + + /* SerialState notification -- CDC 1.1 section 6.3.5 (OUTPUT) */ + u16 serial_state; +#define ACM_CTRL_OVERRUN (1 << 6) +#define ACM_CTRL_PARITY (1 << 5) +#define ACM_CTRL_FRAMING (1 << 4) +#define ACM_CTRL_RI (1 << 3) +#define ACM_CTRL_BRK (1 << 2) +#define ACM_CTRL_DSR (1 << 1) +#define ACM_CTRL_DCD (1 << 0) }; static inline struct f_acm *func_to_acm(struct usb_function *f) @@ -64,12 +85,17 @@ static inline struct f_acm *func_to_acm(struct usb_function *f) return container_of(f, struct f_acm, port.func); } +static inline struct f_acm *port_to_acm(struct gserial *p) +{ + return container_of(p, struct f_acm, port); +} + /*-------------------------------------------------------------------------*/ /* notification endpoint uses smallish and infrequent fixed-size messages */ #define GS_LOG2_NOTIFY_INTERVAL 5 /* 1 << 5 == 32 msec */ -#define GS_NOTIFY_MAXPACKET 8 +#define GS_NOTIFY_MAXPACKET 10 /* notification + 2 bytes */ /* interface and class descriptors: */ @@ -115,7 +141,7 @@ static struct usb_cdc_acm_descriptor acm_descriptor __initdata = { .bLength = sizeof(acm_descriptor), .bDescriptorType = USB_DT_CS_INTERFACE, .bDescriptorSubType = USB_CDC_ACM_TYPE, - .bmCapabilities = (1 << 1), + .bmCapabilities = USB_CDC_CAP_LINE, }; static struct usb_cdc_union_desc acm_union_desc __initdata = { @@ -275,6 +301,11 @@ static int acm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl) /* composite driver infrastructure handles everything except * CDC class messages; interface activation uses set_alt(). + * + * Note CDC spec table 4 lists the ACM request profile. It requires + * encapsulated command support ... we don't handle any, and respond + * to them by stalling. Options include get/set/clear comm features + * (not that useful) and SEND_BREAK. */ switch ((ctrl->bRequestType << 8) | ctrl->bRequest) { @@ -310,7 +341,7 @@ static int acm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl) value = 0; /* FIXME we should not allow data to flow until the - * host sets the RS232_DTR bit; and when it clears + * host sets the ACM_CTRL_DTR bit; and when it clears * that bit, we should return to that no-flow state. */ acm->port_handshake_bits = w_value; @@ -348,9 +379,6 @@ static int acm_set_alt(struct usb_function *f, unsigned intf, unsigned alt) /* we know alt == 0, so this is an activation or a reset */ if (intf == acm->ctrl_id) { - /* REVISIT this may need more work when we start to - * send notifications ... - */ if (acm->notify->driver_data) { VDBG(cdev, "reset acm control interface %d\n", intf); usb_ep_disable(acm->notify); @@ -395,6 +423,128 @@ static void acm_disable(struct usb_function *f) /*-------------------------------------------------------------------------*/ +/** + * acm_cdc_notify - issue CDC notification to host + * @acm: wraps host to be notified + * @type: notification type + * @value: Refer to cdc specs, wValue field. + * @data: data to be sent + * @length: size of data + * Context: irqs blocked, acm->lock held, acm_notify_req non-null + * + * Returns zero on sucess or a negative errno. + * + * See section 6.3.5 of the CDC 1.1 specification for information + * about the only notification we issue: SerialState change. + */ +static int acm_cdc_notify(struct f_acm *acm, u8 type, u16 value, + void *data, unsigned length) +{ + struct usb_ep *ep = acm->notify; + struct usb_request *req; + struct usb_cdc_notification *notify; + const unsigned len = sizeof(*notify) + length; + void *buf; + int status; + + req = acm->notify_req; + acm->notify_req = NULL; + acm->pending = false; + + req->length = len; + notify = req->buf; + buf = notify + 1; + + notify->bmRequestType = USB_DIR_IN | USB_TYPE_CLASS + | USB_RECIP_INTERFACE; + notify->bNotificationType = type; + notify->wValue = cpu_to_le16(value); + notify->wIndex = cpu_to_le16(acm->ctrl_id); + notify->wLength = cpu_to_le16(length); + memcpy(buf, data, length); + + status = usb_ep_queue(ep, req, GFP_ATOMIC); + if (status < 0) { + ERROR(acm->port.func.config->cdev, + "acm ttyGS%d can't notify serial state, %d\n", + acm->port_num, status); + acm->notify_req = req; + } + + return status; +} + +static int acm_notify_serial_state(struct f_acm *acm) +{ + struct usb_composite_dev *cdev = acm->port.func.config->cdev; + int status; + + spin_lock(&acm->lock); + if (acm->notify_req) { + DBG(cdev, "acm ttyGS%d serial state %04x\n", + acm->port_num, acm->serial_state); + status = acm_cdc_notify(acm, USB_CDC_NOTIFY_SERIAL_STATE, + 0, &acm->serial_state, sizeof(acm->serial_state)); + } else { + acm->pending = true; + status = 0; + } + spin_unlock(&acm->lock); + return status; +} + +static void acm_cdc_notify_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct f_acm *acm = req->context; + u8 doit = false; + + /* on this call path we do NOT hold the port spinlock, + * which is why ACM needs its own spinlock + */ + spin_lock(&acm->lock); + if (req->status != -ESHUTDOWN) + doit = acm->pending; + acm->notify_req = req; + spin_unlock(&acm->lock); + + if (doit) + acm_notify_serial_state(acm); +} + +/* connect == the TTY link is open */ + +static void acm_connect(struct gserial *port) +{ + struct f_acm *acm = port_to_acm(port); + + acm->serial_state |= ACM_CTRL_DSR | ACM_CTRL_DCD; + acm_notify_serial_state(acm); +} + +static void acm_disconnect(struct gserial *port) +{ + struct f_acm *acm = port_to_acm(port); + + acm->serial_state &= ~(ACM_CTRL_DSR | ACM_CTRL_DCD); + acm_notify_serial_state(acm); +} + +static int acm_send_break(struct gserial *port, int duration) +{ + struct f_acm *acm = port_to_acm(port); + u16 state; + + state = acm->serial_state; + state &= ~ACM_CTRL_BRK; + if (duration) + state |= ACM_CTRL_BRK; + + acm->serial_state = state; + return acm_notify_serial_state(acm); +} + +/*-------------------------------------------------------------------------*/ + /* ACM function driver setup/binding */ static int __init acm_bind(struct usb_configuration *c, struct usb_function *f) @@ -443,8 +593,20 @@ acm_bind(struct usb_configuration *c, struct usb_function *f) acm->notify = ep; ep->driver_data = cdev; /* claim */ + /* allocate notification */ + acm->notify_req = gs_alloc_req(ep, + sizeof(struct usb_cdc_notification) + 2, + GFP_KERNEL); + if (!acm->notify_req) + goto fail; + + acm->notify_req->complete = acm_cdc_notify_complete; + acm->notify_req->context = acm; + /* copy descriptors, and track endpoint copies */ f->descriptors = usb_copy_descriptors(acm_fs_function); + if (!f->descriptors) + goto fail; acm->fs.in = usb_find_endpoint(acm_fs_function, f->descriptors, &acm_fs_in_desc); @@ -476,8 +638,6 @@ acm_bind(struct usb_configuration *c, struct usb_function *f) f->hs_descriptors, &acm_hs_notify_desc); } - /* FIXME provide a callback for triggering notifications */ - DBG(cdev, "acm ttyGS%d: %s speed IN/%s OUT/%s NOTIFY/%s\n", acm->port_num, gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full", @@ -486,6 +646,9 @@ acm_bind(struct usb_configuration *c, struct usb_function *f) return 0; fail: + if (acm->notify_req) + gs_free_req(acm->notify, acm->notify_req); + /* we might as well release our claims on endpoints */ if (acm->notify) acm->notify->driver_data = NULL; @@ -502,10 +665,13 @@ fail: static void acm_unbind(struct usb_configuration *c, struct usb_function *f) { + struct f_acm *acm = func_to_acm(f); + if (gadget_is_dualspeed(c->cdev->gadget)) usb_free_descriptors(f->hs_descriptors); usb_free_descriptors(f->descriptors); - kfree(func_to_acm(f)); + gs_free_req(acm->notify, acm->notify_req); + kfree(acm); } /* Some controllers can't support CDC ACM ... */ @@ -569,8 +735,14 @@ int __init acm_bind_config(struct usb_configuration *c, u8 port_num) if (!acm) return -ENOMEM; + spin_lock_init(&acm->lock); + acm->port_num = port_num; + acm->port.connect = acm_connect; + acm->port.disconnect = acm_disconnect; + acm->port.send_break = acm_send_break; + acm->port.func.name = "acm"; acm->port.func.strings = acm_strings; /* descriptors are per-instance copies */ diff --git a/drivers/usb/gadget/u_serial.c b/drivers/usb/gadget/u_serial.c index 6641efa..53d5928 100644 --- a/drivers/usb/gadget/u_serial.c +++ b/drivers/usb/gadget/u_serial.c @@ -60,7 +60,8 @@ * tty_struct links to the tty/filesystem framework * * gserial <---> gs_port ... links will be null when the USB link is - * inactive; managed by gserial_{connect,disconnect}(). + * inactive; managed by gserial_{connect,disconnect}(). each gserial + * instance can wrap its own USB control protocol. * gserial->ioport == usb_ep->driver_data ... gs_port * gs_port->port_usb ... gserial * @@ -181,7 +182,7 @@ static void gs_buf_clear(struct gs_buf *gb) /* * gs_buf_data_avail * - * Return the number of bytes of data available in the circular + * Return the number of bytes of data written into the circular * buffer. */ static unsigned gs_buf_data_avail(struct gs_buf *gb) @@ -282,7 +283,7 @@ gs_buf_get(struct gs_buf *gb, char *buf, unsigned count) * Allocate a usb_request and its buffer. Returns a pointer to the * usb_request or NULL if there is an error. */ -static struct usb_request * +struct usb_request * gs_alloc_req(struct usb_ep *ep, unsigned len, gfp_t kmalloc_flags) { struct usb_request *req; @@ -306,7 +307,7 @@ gs_alloc_req(struct usb_ep *ep, unsigned len, gfp_t kmalloc_flags) * * Free a usb_request and its buffer. */ -static void gs_free_req(struct usb_ep *ep, struct usb_request *req) +void gs_free_req(struct usb_ep *ep, struct usb_request *req) { kfree(req->buf); usb_ep_free_request(ep, req); @@ -788,10 +789,13 @@ static int gs_open(struct tty_struct *tty, struct file *file) /* if connected, start the I/O stream */ if (port->port_usb) { + struct gserial *gser = port->port_usb; + pr_debug("gs_open: start ttyGS%d\n", port->port_num); gs_start_io(port); - /* REVISIT for ACM, issue "network connected" event */ + if (gser->connect) + gser->connect(gser); } pr_debug("gs_open: ttyGS%d (%p,%p)\n", port->port_num, tty, file); @@ -818,6 +822,7 @@ static int gs_writes_finished(struct gs_port *p) static void gs_close(struct tty_struct *tty, struct file *file) { struct gs_port *port = tty->driver_data; + struct gserial *gser; spin_lock_irq(&port->port_lock); @@ -837,26 +842,27 @@ static void gs_close(struct tty_struct *tty, struct file *file) port->openclose = true; port->open_count = 0; - if (port->port_usb) - /* REVISIT for ACM, issue "network disconnected" event */; + gser = port->port_usb; + if (gser && gser->disconnect) + gser->disconnect(gser); /* wait for circular write buffer to drain, disconnect, or at * most GS_CLOSE_TIMEOUT seconds; then discard the rest */ - if (gs_buf_data_avail(&port->port_write_buf) > 0 - && port->port_usb) { + if (gs_buf_data_avail(&port->port_write_buf) > 0 && gser) { spin_unlock_irq(&port->port_lock); wait_event_interruptible_timeout(port->drain_wait, gs_writes_finished(port), GS_CLOSE_TIMEOUT * HZ); spin_lock_irq(&port->port_lock); + gser = port->port_usb; } /* Iff we're disconnected, there can be no I/O in flight so it's * ok to free the circular buffer; else just scrub it. And don't * let the push tasklet fire again until we're re-opened. */ - if (port->port_usb == NULL) + if (gser == NULL) gs_buf_free(&port->port_write_buf); else gs_buf_clear(&port->port_write_buf); @@ -974,6 +980,24 @@ static void gs_unthrottle(struct tty_struct *tty) spin_unlock_irqrestore(&port->port_lock, flags); } +static int gs_break_ctl(struct tty_struct *tty, int duration) +{ + struct gs_port *port = tty->driver_data; + int status = 0; + struct gserial *gser; + + pr_vdebug("gs_break_ctl: ttyGS%d, send break (%d) \n", + port->port_num, duration); + + spin_lock_irq(&port->port_lock); + gser = port->port_usb; + if (gser && gser->send_break) + status = gser->send_break(gser, duration); + spin_unlock_irq(&port->port_lock); + + return status; +} + static const struct tty_operations gs_tty_ops = { .open = gs_open, .close = gs_close, @@ -983,6 +1007,7 @@ static const struct tty_operations gs_tty_ops = { .write_room = gs_write_room, .chars_in_buffer = gs_chars_in_buffer, .unthrottle = gs_unthrottle, + .break_ctl = gs_break_ctl, }; /*-------------------------------------------------------------------------*/ @@ -1230,14 +1255,17 @@ int gserial_connect(struct gserial *gser, u8 port_num) /* REVISIT if waiting on "carrier detect", signal. */ - /* REVISIT for ACM, issue "network connection" status notification: - * connected if open_count, else disconnected. + /* if it's already open, start I/O ... and notify the serial + * protocol about open/close status (connect/disconnect). */ - - /* if it's already open, start I/O */ if (port->open_count) { pr_debug("gserial_connect: start ttyGS%d\n", port->port_num); gs_start_io(port); + if (gser->connect) + gser->connect(gser); + } else { + if (gser->disconnect) + gser->disconnect(gser); } spin_unlock_irqrestore(&port->port_lock, flags); diff --git a/drivers/usb/gadget/u_serial.h b/drivers/usb/gadget/u_serial.h index 7b561138..af3910d 100644 --- a/drivers/usb/gadget/u_serial.h +++ b/drivers/usb/gadget/u_serial.h @@ -23,8 +23,7 @@ * style I/O using the USB peripheral endpoints listed here, including * hookups to sysfs and /dev for each logical "tty" device. * - * REVISIT need TTY --> USB event flow too, so ACM can report open/close - * as carrier detect events. Model after ECM. There's more ACM state too. + * REVISIT at least ACM could support tiocmget() if needed. * * REVISIT someday, allow multiplexing several TTYs over these endpoints. */ @@ -41,8 +40,17 @@ struct gserial { /* REVISIT avoid this CDC-ACM support harder ... */ struct usb_cdc_line_coding port_line_coding; /* 9600-8-N-1 etc */ + + /* notification callbacks */ + void (*connect)(struct gserial *p); + void (*disconnect)(struct gserial *p); + int (*send_break)(struct gserial *p, int duration); }; +/* utilities to allocate/free request and buffer */ +struct usb_request *gs_alloc_req(struct usb_ep *ep, unsigned len, gfp_t flags); +void gs_free_req(struct usb_ep *, struct usb_request *req); + /* port setup/teardown is handled by gadget driver */ int gserial_setup(struct usb_gadget *g, unsigned n_ports); void gserial_cleanup(void); |