From f371e750c9324f3498842ee833a0242a11b359e6 Mon Sep 17 00:00:00 2001 From: David Brownell Date: Fri, 18 Apr 2008 17:37:49 -0700 Subject: [PATCH] usb serial gadget: CDC ACM fixes Based on a patch from , this makes the CDC-ACM support in the serial gadget handle the SET_LINE_CODING and SET_CONTROL_LINE_STATE requests ... which should improve interop with at least MS-Windows "usbser.sys" if not some other ACM host drivers. It also adds a few REVISIT comments where this code plays a bit loose with the CDC ACM spec. If this were used to hook up to a real RS232 or modem link, those places would need a bit of work. Signed-off-by: David Brownell Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/serial.c | 90 ++++++++++++++++++++++++++++++------- 1 file changed, 73 insertions(+), 17 deletions(-) diff --git a/drivers/usb/gadget/serial.c b/drivers/usb/gadget/serial.c index 8d158e5640e..54cdd6f9403 100644 --- a/drivers/usb/gadget/serial.c +++ b/drivers/usb/gadget/serial.c @@ -135,7 +135,10 @@ struct gs_port { int port_in_use; /* open/close in progress */ wait_queue_head_t port_write_wait;/* waiting to write */ struct gs_buf *port_write_buf; - struct usb_cdc_line_coding port_line_coding; + struct usb_cdc_line_coding port_line_coding; /* 8-N-1 etc */ + u16 port_handshake_bits; +#define RS232_RTS (1 << 1) +#define RS232_DTE (1 << 0) }; /* the device structure holds info for the USB device */ @@ -199,6 +202,8 @@ static int gs_setup_standard(struct usb_gadget *gadget, static int gs_setup_class(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl); static void gs_setup_complete(struct usb_ep *ep, struct usb_request *req); +static void gs_setup_complete_set_line_coding(struct usb_ep *ep, + struct usb_request *req); static void gs_disconnect(struct usb_gadget *gadget); static int gs_set_config(struct gs_dev *dev, unsigned config); static void gs_reset_config(struct gs_dev *dev); @@ -406,7 +411,7 @@ static struct usb_cdc_acm_descriptor gs_acm_descriptor = { .bLength = sizeof(gs_acm_descriptor), .bDescriptorType = USB_DT_CS_INTERFACE, .bDescriptorSubType = USB_CDC_ACM_TYPE, - .bmCapabilities = 0, + .bmCapabilities = (1 << 1), }; static const struct usb_cdc_union_desc gs_union_desc = { @@ -1502,6 +1507,8 @@ static int gs_setup(struct usb_gadget *gadget, u16 wValue = le16_to_cpu(ctrl->wValue); u16 wLength = le16_to_cpu(ctrl->wLength); + req->complete = gs_setup_complete; + switch (ctrl->bRequestType & USB_TYPE_MASK) { case USB_TYPE_STANDARD: ret = gs_setup_standard(gadget,ctrl); @@ -1679,18 +1686,14 @@ static int gs_setup_class(struct usb_gadget *gadget, switch (ctrl->bRequest) { case USB_CDC_REQ_SET_LINE_CODING: - /* FIXME Submit req to read the data; have its completion - * handler copy that data to port->port_line_coding (iff - * it's valid) and maybe pass it on. Until then, fail. - */ - pr_warning("gs_setup: set_line_coding " - "unuspported\n"); + if (wLength != sizeof(struct usb_cdc_line_coding)) + break; + ret = wLength; + req->complete = gs_setup_complete_set_line_coding; break; case USB_CDC_REQ_GET_LINE_CODING: - port = dev->dev_port[0]; /* ACM only has one port */ - ret = min(wLength, - (u16)sizeof(struct usb_cdc_line_coding)); + ret = min_t(int, wLength, sizeof(struct usb_cdc_line_coding)); if (port) { spin_lock(&port->port_lock); memcpy(req->buf, &port->port_line_coding, ret); @@ -1699,15 +1702,27 @@ static int gs_setup_class(struct usb_gadget *gadget, break; case USB_CDC_REQ_SET_CONTROL_LINE_STATE: - /* FIXME Submit req to read the data; have its completion - * handler use that to set the state (iff it's valid) and - * maybe pass it on. Until then, fail. - */ - pr_warning("gs_setup: set_control_line_state " - "unuspported\n"); + if (wLength != 0) + break; + ret = 0; + if (port) { + /* REVISIT: we currently just remember this data. + * If we change that, update whatever hardware needs + * updating. + */ + spin_lock(&port->port_lock); + port->port_handshake_bits = wValue; + spin_unlock(&port->port_lock); + } break; default: + /* NOTE: strictly speaking, we should accept AT-commands + * using SEND_ENCPSULATED_COMMAND/GET_ENCAPSULATED_RESPONSE. + * But our call management descriptor says we don't handle + * call management, so we should be able to get by without + * handling those "required" commands (except by stalling). + */ pr_err("gs_setup: unknown class request, " "type=%02x, request=%02x, value=%04x, " "index=%04x, length=%d\n", @@ -1719,6 +1734,42 @@ static int gs_setup_class(struct usb_gadget *gadget, return ret; } +static void gs_setup_complete_set_line_coding(struct usb_ep *ep, + struct usb_request *req) +{ + struct gs_dev *dev = ep->driver_data; + struct gs_port *port = dev->dev_port[0]; /* ACM only has one port */ + + switch (req->status) { + case 0: + /* normal completion */ + if (req->actual != sizeof(port->port_line_coding)) + usb_ep_set_halt(ep); + else if (port) { + struct usb_cdc_line_coding *value = req->buf; + + /* REVISIT: we currently just remember this data. + * If we change that, (a) validate it first, then + * (b) update whatever hardware needs updating. + */ + spin_lock(&port->port_lock); + port->port_line_coding = *value; + spin_unlock(&port->port_lock); + } + break; + + case -ESHUTDOWN: + /* disconnect */ + gs_free_req(ep, req); + break; + + default: + /* unexpected */ + break; + } + return; +} + /* * gs_setup_complete */ @@ -1906,6 +1957,11 @@ static int gs_set_config(struct gs_dev *dev, unsigned config) } } + /* REVISIT the ACM mode should be able to actually *issue* some + * notifications, for at least serial state change events if + * not also for network connection; say so in bmCapabilities. + */ + pr_info("gs_set_config: %s configured, %s speed %s config\n", GS_LONG_NAME, gadget->speed == USB_SPEED_HIGH ? "high" : "full", -- 2.20.1