summaryrefslogtreecommitdiffstats
path: root/drivers/usb/gadget/function/f_acm.c
diff options
context:
space:
mode:
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/gadget/function/f_acm.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 'drivers/usb/gadget/function/f_acm.c')
-rw-r--r--drivers/usb/gadget/function/f_acm.c859
1 files changed, 859 insertions, 0 deletions
diff --git a/drivers/usb/gadget/function/f_acm.c b/drivers/usb/gadget/function/f_acm.c
new file mode 100644
index 000000000..cb523f118
--- /dev/null
+++ b/drivers/usb/gadget/function/f_acm.c
@@ -0,0 +1,859 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * f_acm.c -- USB CDC serial (ACM) function driver
+ *
+ * Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com)
+ * Copyright (C) 2008 by David Brownell
+ * Copyright (C) 2008 by Nokia Corporation
+ * Copyright (C) 2009 by Samsung Electronics
+ * Author: Michal Nazarewicz (mina86@mina86.com)
+ */
+
+/* #define VERBOSE_DEBUG */
+
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/err.h>
+
+#include "u_serial.h"
+
+
+/*
+ * This CDC ACM function support just wraps control functions and
+ * notifications around the generic serial-over-usb code.
+ *
+ * Because CDC ACM is standardized by the USB-IF, many host operating
+ * systems have drivers for it. Accordingly, ACM is the preferred
+ * interop solution for serial-port type connections. The control
+ * models are often not necessary, and in any case don't do much in
+ * this bare-bones implementation.
+ *
+ * Note that even MS-Windows has some support for ACM. However, that
+ * support is somewhat broken because when you use ACM in a composite
+ * device, having multiple interfaces confuses the poor OS. It doesn't
+ * seem to understand CDC Union descriptors. The new "association"
+ * descriptors (roughly equivalent to CDC Unions) may sometimes help.
+ */
+
+struct f_acm {
+ struct gserial port;
+ 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 usb_ep *notify;
+ 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;
+ /* SerialState notification -- CDC 1.1 section 6.3.5 (OUTPUT) */
+ u16 serial_state;
+};
+
+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_NOTIFY_INTERVAL_MS 32
+#define GS_NOTIFY_MAXPACKET 10 /* notification + 2 bytes */
+
+/* interface and class descriptors: */
+
+static struct usb_interface_assoc_descriptor
+acm_iad_descriptor = {
+ .bLength = sizeof acm_iad_descriptor,
+ .bDescriptorType = USB_DT_INTERFACE_ASSOCIATION,
+
+ /* .bFirstInterface = DYNAMIC, */
+ .bInterfaceCount = 2, // control + data
+ .bFunctionClass = USB_CLASS_COMM,
+ .bFunctionSubClass = USB_CDC_SUBCLASS_ACM,
+ .bFunctionProtocol = USB_CDC_ACM_PROTO_AT_V25TER,
+ /* .iFunction = DYNAMIC */
+};
+
+
+static struct usb_interface_descriptor acm_control_interface_desc = {
+ .bLength = USB_DT_INTERFACE_SIZE,
+ .bDescriptorType = USB_DT_INTERFACE,
+ /* .bInterfaceNumber = DYNAMIC */
+ .bNumEndpoints = 1,
+ .bInterfaceClass = USB_CLASS_COMM,
+ .bInterfaceSubClass = USB_CDC_SUBCLASS_ACM,
+ .bInterfaceProtocol = USB_CDC_ACM_PROTO_AT_V25TER,
+ /* .iInterface = DYNAMIC */
+};
+
+static struct usb_interface_descriptor acm_data_interface_desc = {
+ .bLength = USB_DT_INTERFACE_SIZE,
+ .bDescriptorType = USB_DT_INTERFACE,
+ /* .bInterfaceNumber = DYNAMIC */
+ .bNumEndpoints = 2,
+ .bInterfaceClass = USB_CLASS_CDC_DATA,
+ .bInterfaceSubClass = 0,
+ .bInterfaceProtocol = 0,
+ /* .iInterface = DYNAMIC */
+};
+
+static struct usb_cdc_header_desc acm_header_desc = {
+ .bLength = sizeof(acm_header_desc),
+ .bDescriptorType = USB_DT_CS_INTERFACE,
+ .bDescriptorSubType = USB_CDC_HEADER_TYPE,
+ .bcdCDC = cpu_to_le16(0x0110),
+};
+
+static struct usb_cdc_call_mgmt_descriptor
+acm_call_mgmt_descriptor = {
+ .bLength = sizeof(acm_call_mgmt_descriptor),
+ .bDescriptorType = USB_DT_CS_INTERFACE,
+ .bDescriptorSubType = USB_CDC_CALL_MANAGEMENT_TYPE,
+ .bmCapabilities = 0,
+ /* .bDataInterface = DYNAMIC */
+};
+
+static struct usb_cdc_acm_descriptor acm_descriptor = {
+ .bLength = sizeof(acm_descriptor),
+ .bDescriptorType = USB_DT_CS_INTERFACE,
+ .bDescriptorSubType = USB_CDC_ACM_TYPE,
+ .bmCapabilities = USB_CDC_CAP_LINE,
+};
+
+static struct usb_cdc_union_desc acm_union_desc = {
+ .bLength = sizeof(acm_union_desc),
+ .bDescriptorType = USB_DT_CS_INTERFACE,
+ .bDescriptorSubType = USB_CDC_UNION_TYPE,
+ /* .bMasterInterface0 = DYNAMIC */
+ /* .bSlaveInterface0 = DYNAMIC */
+};
+
+/* full speed support: */
+
+static struct usb_endpoint_descriptor acm_fs_notify_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_INT,
+ .wMaxPacketSize = cpu_to_le16(GS_NOTIFY_MAXPACKET),
+ .bInterval = GS_NOTIFY_INTERVAL_MS,
+};
+
+static struct usb_endpoint_descriptor acm_fs_in_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+};
+
+static struct usb_endpoint_descriptor acm_fs_out_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_OUT,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+};
+
+static struct usb_descriptor_header *acm_fs_function[] = {
+ (struct usb_descriptor_header *) &acm_iad_descriptor,
+ (struct usb_descriptor_header *) &acm_control_interface_desc,
+ (struct usb_descriptor_header *) &acm_header_desc,
+ (struct usb_descriptor_header *) &acm_call_mgmt_descriptor,
+ (struct usb_descriptor_header *) &acm_descriptor,
+ (struct usb_descriptor_header *) &acm_union_desc,
+ (struct usb_descriptor_header *) &acm_fs_notify_desc,
+ (struct usb_descriptor_header *) &acm_data_interface_desc,
+ (struct usb_descriptor_header *) &acm_fs_in_desc,
+ (struct usb_descriptor_header *) &acm_fs_out_desc,
+ NULL,
+};
+
+/* high speed support: */
+static struct usb_endpoint_descriptor acm_hs_notify_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_INT,
+ .wMaxPacketSize = cpu_to_le16(GS_NOTIFY_MAXPACKET),
+ .bInterval = USB_MS_TO_HS_INTERVAL(GS_NOTIFY_INTERVAL_MS),
+};
+
+static struct usb_endpoint_descriptor acm_hs_in_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = cpu_to_le16(512),
+};
+
+static struct usb_endpoint_descriptor acm_hs_out_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = cpu_to_le16(512),
+};
+
+static struct usb_descriptor_header *acm_hs_function[] = {
+ (struct usb_descriptor_header *) &acm_iad_descriptor,
+ (struct usb_descriptor_header *) &acm_control_interface_desc,
+ (struct usb_descriptor_header *) &acm_header_desc,
+ (struct usb_descriptor_header *) &acm_call_mgmt_descriptor,
+ (struct usb_descriptor_header *) &acm_descriptor,
+ (struct usb_descriptor_header *) &acm_union_desc,
+ (struct usb_descriptor_header *) &acm_hs_notify_desc,
+ (struct usb_descriptor_header *) &acm_data_interface_desc,
+ (struct usb_descriptor_header *) &acm_hs_in_desc,
+ (struct usb_descriptor_header *) &acm_hs_out_desc,
+ NULL,
+};
+
+static struct usb_endpoint_descriptor acm_ss_in_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = cpu_to_le16(1024),
+};
+
+static struct usb_endpoint_descriptor acm_ss_out_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = cpu_to_le16(1024),
+};
+
+static struct usb_ss_ep_comp_descriptor acm_ss_bulk_comp_desc = {
+ .bLength = sizeof acm_ss_bulk_comp_desc,
+ .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
+};
+
+static struct usb_descriptor_header *acm_ss_function[] = {
+ (struct usb_descriptor_header *) &acm_iad_descriptor,
+ (struct usb_descriptor_header *) &acm_control_interface_desc,
+ (struct usb_descriptor_header *) &acm_header_desc,
+ (struct usb_descriptor_header *) &acm_call_mgmt_descriptor,
+ (struct usb_descriptor_header *) &acm_descriptor,
+ (struct usb_descriptor_header *) &acm_union_desc,
+ (struct usb_descriptor_header *) &acm_hs_notify_desc,
+ (struct usb_descriptor_header *) &acm_ss_bulk_comp_desc,
+ (struct usb_descriptor_header *) &acm_data_interface_desc,
+ (struct usb_descriptor_header *) &acm_ss_in_desc,
+ (struct usb_descriptor_header *) &acm_ss_bulk_comp_desc,
+ (struct usb_descriptor_header *) &acm_ss_out_desc,
+ (struct usb_descriptor_header *) &acm_ss_bulk_comp_desc,
+ NULL,
+};
+
+/* string descriptors: */
+
+#define ACM_CTRL_IDX 0
+#define ACM_DATA_IDX 1
+#define ACM_IAD_IDX 2
+
+/* static strings, in UTF-8 */
+static struct usb_string acm_string_defs[] = {
+ [ACM_CTRL_IDX].s = "CDC Abstract Control Model (ACM)",
+ [ACM_DATA_IDX].s = "CDC ACM Data",
+ [ACM_IAD_IDX ].s = "CDC Serial",
+ { } /* end of list */
+};
+
+static struct usb_gadget_strings acm_string_table = {
+ .language = 0x0409, /* en-us */
+ .strings = acm_string_defs,
+};
+
+static struct usb_gadget_strings *acm_strings[] = {
+ &acm_string_table,
+ NULL,
+};
+
+/*-------------------------------------------------------------------------*/
+
+/* ACM control ... data handling is delegated to tty library code.
+ * The main task of this function is to activate and deactivate
+ * that code based on device state; track parameters like line
+ * speed, handshake state, and so on; and issue notifications.
+ */
+
+static void acm_complete_set_line_coding(struct usb_ep *ep,
+ struct usb_request *req)
+{
+ struct f_acm *acm = ep->driver_data;
+ struct usb_composite_dev *cdev = acm->port.func.config->cdev;
+
+ if (req->status != 0) {
+ dev_dbg(&cdev->gadget->dev, "acm ttyGS%d completion, err %d\n",
+ acm->port_num, req->status);
+ return;
+ }
+
+ /* normal completion */
+ if (req->actual != sizeof(acm->port_line_coding)) {
+ dev_dbg(&cdev->gadget->dev, "acm ttyGS%d short resp, len %d\n",
+ acm->port_num, req->actual);
+ usb_ep_set_halt(ep);
+ } else {
+ 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,
+ * (c) worry about locking. This is information on
+ * the order of 9600-8-N-1 ... most of which means
+ * nothing unless we control a real RS232 line.
+ */
+ acm->port_line_coding = *value;
+ }
+}
+
+static int acm_send_break(struct gserial *port, int duration);
+
+static int acm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
+{
+ struct f_acm *acm = func_to_acm(f);
+ struct usb_composite_dev *cdev = f->config->cdev;
+ struct usb_request *req = cdev->req;
+ int value = -EOPNOTSUPP;
+ u16 w_index = le16_to_cpu(ctrl->wIndex);
+ u16 w_value = le16_to_cpu(ctrl->wValue);
+ u16 w_length = le16_to_cpu(ctrl->wLength);
+
+ /* 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) {
+
+ /* SET_LINE_CODING ... just read and save what the host sends */
+ case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
+ | USB_CDC_REQ_SET_LINE_CODING:
+ if (w_length != sizeof(struct usb_cdc_line_coding)
+ || w_index != acm->ctrl_id)
+ goto invalid;
+
+ value = w_length;
+ cdev->gadget->ep0->driver_data = acm;
+ req->complete = acm_complete_set_line_coding;
+ break;
+
+ /* GET_LINE_CODING ... return what host sent, or initial value */
+ case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
+ | USB_CDC_REQ_GET_LINE_CODING:
+ if (w_index != acm->ctrl_id)
+ goto invalid;
+
+ value = min_t(unsigned, w_length,
+ sizeof(struct usb_cdc_line_coding));
+ memcpy(req->buf, &acm->port_line_coding, value);
+ break;
+
+ /* SET_CONTROL_LINE_STATE ... save what the host sent */
+ case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
+ | USB_CDC_REQ_SET_CONTROL_LINE_STATE:
+ if (w_index != acm->ctrl_id)
+ goto invalid;
+
+ value = 0;
+
+ /* FIXME we should not allow data to flow until the
+ * host sets the USB_CDC_CTRL_DTR bit; and when it clears
+ * that bit, we should return to that no-flow state.
+ */
+ acm->port_handshake_bits = w_value;
+ break;
+
+ case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
+ | USB_CDC_REQ_SEND_BREAK:
+ if (w_index != acm->ctrl_id)
+ goto invalid;
+
+ acm_send_break(&acm->port, w_value);
+ break;
+
+ default:
+invalid:
+ dev_vdbg(&cdev->gadget->dev,
+ "invalid control req%02x.%02x v%04x i%04x l%d\n",
+ ctrl->bRequestType, ctrl->bRequest,
+ w_value, w_index, w_length);
+ }
+
+ /* respond with data transfer or status phase? */
+ if (value >= 0) {
+ dev_dbg(&cdev->gadget->dev,
+ "acm ttyGS%d req%02x.%02x v%04x i%04x l%d\n",
+ acm->port_num, ctrl->bRequestType, ctrl->bRequest,
+ w_value, w_index, w_length);
+ req->zero = 0;
+ req->length = value;
+ value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
+ if (value < 0)
+ ERROR(cdev, "acm response on ttyGS%d, err %d\n",
+ acm->port_num, value);
+ }
+
+ /* device either stalls (value < 0) or reports success */
+ return value;
+}
+
+static int acm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
+{
+ struct f_acm *acm = func_to_acm(f);
+ struct usb_composite_dev *cdev = f->config->cdev;
+
+ /* we know alt == 0, so this is an activation or a reset */
+
+ if (intf == acm->ctrl_id) {
+ if (acm->notify->enabled) {
+ dev_vdbg(&cdev->gadget->dev,
+ "reset acm control interface %d\n", intf);
+ usb_ep_disable(acm->notify);
+ }
+
+ if (!acm->notify->desc)
+ if (config_ep_by_speed(cdev->gadget, f, acm->notify))
+ return -EINVAL;
+
+ usb_ep_enable(acm->notify);
+
+ } else if (intf == acm->data_id) {
+ if (acm->notify->enabled) {
+ dev_dbg(&cdev->gadget->dev,
+ "reset acm ttyGS%d\n", acm->port_num);
+ gserial_disconnect(&acm->port);
+ }
+ if (!acm->port.in->desc || !acm->port.out->desc) {
+ dev_dbg(&cdev->gadget->dev,
+ "activate acm ttyGS%d\n", acm->port_num);
+ if (config_ep_by_speed(cdev->gadget, f,
+ acm->port.in) ||
+ config_ep_by_speed(cdev->gadget, f,
+ acm->port.out)) {
+ acm->port.in->desc = NULL;
+ acm->port.out->desc = NULL;
+ return -EINVAL;
+ }
+ }
+ gserial_connect(&acm->port, acm->port_num);
+
+ } else
+ return -EINVAL;
+
+ return 0;
+}
+
+static void acm_disable(struct usb_function *f)
+{
+ struct f_acm *acm = func_to_acm(f);
+ struct usb_composite_dev *cdev = f->config->cdev;
+
+ dev_dbg(&cdev->gadget->dev, "acm ttyGS%d deactivated\n", acm->port_num);
+ gserial_disconnect(&acm->port);
+ usb_ep_disable(acm->notify);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/**
+ * 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 success 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);
+
+ /* ep_queue() can complete immediately if it fills the fifo... */
+ spin_unlock(&acm->lock);
+ status = usb_ep_queue(ep, req, GFP_ATOMIC);
+ spin_lock(&acm->lock);
+
+ 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;
+ __le16 serial_state;
+
+ spin_lock(&acm->lock);
+ if (acm->notify_req) {
+ dev_dbg(&cdev->gadget->dev, "acm ttyGS%d serial state %04x\n",
+ acm->port_num, acm->serial_state);
+ serial_state = cpu_to_le16(acm->serial_state);
+ status = acm_cdc_notify(acm, USB_CDC_NOTIFY_SERIAL_STATE,
+ 0, &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 |= USB_CDC_SERIAL_STATE_DSR | USB_CDC_SERIAL_STATE_DCD;
+ acm_notify_serial_state(acm);
+}
+
+static void acm_disconnect(struct gserial *port)
+{
+ struct f_acm *acm = port_to_acm(port);
+
+ acm->serial_state &= ~(USB_CDC_SERIAL_STATE_DSR | USB_CDC_SERIAL_STATE_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 &= ~USB_CDC_SERIAL_STATE_BREAK;
+ if (duration)
+ state |= USB_CDC_SERIAL_STATE_BREAK;
+
+ acm->serial_state = state;
+ return acm_notify_serial_state(acm);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* ACM function driver setup/binding */
+static int
+acm_bind(struct usb_configuration *c, struct usb_function *f)
+{
+ struct usb_composite_dev *cdev = c->cdev;
+ struct f_acm *acm = func_to_acm(f);
+ struct usb_string *us;
+ int status;
+ struct usb_ep *ep;
+
+ /* REVISIT might want instance-specific strings to help
+ * distinguish instances ...
+ */
+
+ /* maybe allocate device-global string IDs, and patch descriptors */
+ us = usb_gstrings_attach(cdev, acm_strings,
+ ARRAY_SIZE(acm_string_defs));
+ if (IS_ERR(us))
+ return PTR_ERR(us);
+ acm_control_interface_desc.iInterface = us[ACM_CTRL_IDX].id;
+ acm_data_interface_desc.iInterface = us[ACM_DATA_IDX].id;
+ acm_iad_descriptor.iFunction = us[ACM_IAD_IDX].id;
+
+ /* allocate instance-specific interface IDs, and patch descriptors */
+ status = usb_interface_id(c, f);
+ if (status < 0)
+ goto fail;
+ acm->ctrl_id = status;
+ acm_iad_descriptor.bFirstInterface = status;
+
+ acm_control_interface_desc.bInterfaceNumber = status;
+ acm_union_desc .bMasterInterface0 = status;
+
+ status = usb_interface_id(c, f);
+ if (status < 0)
+ goto fail;
+ acm->data_id = status;
+
+ acm_data_interface_desc.bInterfaceNumber = status;
+ acm_union_desc.bSlaveInterface0 = status;
+ acm_call_mgmt_descriptor.bDataInterface = status;
+
+ status = -ENODEV;
+
+ /* allocate instance-specific endpoints */
+ ep = usb_ep_autoconfig(cdev->gadget, &acm_fs_in_desc);
+ if (!ep)
+ goto fail;
+ acm->port.in = ep;
+
+ ep = usb_ep_autoconfig(cdev->gadget, &acm_fs_out_desc);
+ if (!ep)
+ goto fail;
+ acm->port.out = ep;
+
+ ep = usb_ep_autoconfig(cdev->gadget, &acm_fs_notify_desc);
+ if (!ep)
+ goto fail;
+ acm->notify = ep;
+
+ /* 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;
+
+ /* support all relevant hardware speeds... we expect that when
+ * hardware is dual speed, all bulk-capable endpoints work at
+ * both speeds
+ */
+ acm_hs_in_desc.bEndpointAddress = acm_fs_in_desc.bEndpointAddress;
+ acm_hs_out_desc.bEndpointAddress = acm_fs_out_desc.bEndpointAddress;
+ acm_hs_notify_desc.bEndpointAddress =
+ acm_fs_notify_desc.bEndpointAddress;
+
+ acm_ss_in_desc.bEndpointAddress = acm_fs_in_desc.bEndpointAddress;
+ acm_ss_out_desc.bEndpointAddress = acm_fs_out_desc.bEndpointAddress;
+
+ status = usb_assign_descriptors(f, acm_fs_function, acm_hs_function,
+ acm_ss_function, acm_ss_function);
+ if (status)
+ goto fail;
+
+ dev_dbg(&cdev->gadget->dev,
+ "acm ttyGS%d: %s speed IN/%s OUT/%s NOTIFY/%s\n",
+ acm->port_num,
+ gadget_is_superspeed(c->cdev->gadget) ? "super" :
+ gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
+ acm->port.in->name, acm->port.out->name,
+ acm->notify->name);
+ return 0;
+
+fail:
+ if (acm->notify_req)
+ gs_free_req(acm->notify, acm->notify_req);
+
+ ERROR(cdev, "%s/%p: can't bind, err %d\n", f->name, f, status);
+
+ return status;
+}
+
+static void acm_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+ struct f_acm *acm = func_to_acm(f);
+
+ acm_string_defs[0].id = 0;
+ usb_free_all_descriptors(f);
+ if (acm->notify_req)
+ gs_free_req(acm->notify, acm->notify_req);
+}
+
+static void acm_free_func(struct usb_function *f)
+{
+ struct f_acm *acm = func_to_acm(f);
+
+ kfree(acm);
+}
+
+static void acm_resume(struct usb_function *f)
+{
+ struct f_acm *acm = func_to_acm(f);
+
+ gserial_resume(&acm->port);
+}
+
+static void acm_suspend(struct usb_function *f)
+{
+ struct f_acm *acm = func_to_acm(f);
+
+ gserial_suspend(&acm->port);
+}
+
+static struct usb_function *acm_alloc_func(struct usb_function_instance *fi)
+{
+ struct f_serial_opts *opts;
+ struct f_acm *acm;
+
+ acm = kzalloc(sizeof(*acm), GFP_KERNEL);
+ if (!acm)
+ return ERR_PTR(-ENOMEM);
+
+ spin_lock_init(&acm->lock);
+
+ 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 */
+ acm->port.func.bind = acm_bind;
+ acm->port.func.set_alt = acm_set_alt;
+ acm->port.func.setup = acm_setup;
+ acm->port.func.disable = acm_disable;
+
+ opts = container_of(fi, struct f_serial_opts, func_inst);
+ acm->port_num = opts->port_num;
+ acm->port.func.unbind = acm_unbind;
+ acm->port.func.free_func = acm_free_func;
+ acm->port.func.resume = acm_resume;
+ acm->port.func.suspend = acm_suspend;
+
+ return &acm->port.func;
+}
+
+static inline struct f_serial_opts *to_f_serial_opts(struct config_item *item)
+{
+ return container_of(to_config_group(item), struct f_serial_opts,
+ func_inst.group);
+}
+
+static void acm_attr_release(struct config_item *item)
+{
+ struct f_serial_opts *opts = to_f_serial_opts(item);
+
+ usb_put_function_instance(&opts->func_inst);
+}
+
+static struct configfs_item_operations acm_item_ops = {
+ .release = acm_attr_release,
+};
+
+#ifdef CONFIG_U_SERIAL_CONSOLE
+
+static ssize_t f_acm_console_store(struct config_item *item,
+ const char *page, size_t count)
+{
+ return gserial_set_console(to_f_serial_opts(item)->port_num,
+ page, count);
+}
+
+static ssize_t f_acm_console_show(struct config_item *item, char *page)
+{
+ return gserial_get_console(to_f_serial_opts(item)->port_num, page);
+}
+
+CONFIGFS_ATTR(f_acm_, console);
+
+#endif /* CONFIG_U_SERIAL_CONSOLE */
+
+static ssize_t f_acm_port_num_show(struct config_item *item, char *page)
+{
+ return sprintf(page, "%u\n", to_f_serial_opts(item)->port_num);
+}
+
+CONFIGFS_ATTR_RO(f_acm_, port_num);
+
+static struct configfs_attribute *acm_attrs[] = {
+#ifdef CONFIG_U_SERIAL_CONSOLE
+ &f_acm_attr_console,
+#endif
+ &f_acm_attr_port_num,
+ NULL,
+};
+
+static const struct config_item_type acm_func_type = {
+ .ct_item_ops = &acm_item_ops,
+ .ct_attrs = acm_attrs,
+ .ct_owner = THIS_MODULE,
+};
+
+static void acm_free_instance(struct usb_function_instance *fi)
+{
+ struct f_serial_opts *opts;
+
+ opts = container_of(fi, struct f_serial_opts, func_inst);
+ gserial_free_line(opts->port_num);
+ kfree(opts);
+}
+
+static struct usb_function_instance *acm_alloc_instance(void)
+{
+ struct f_serial_opts *opts;
+ int ret;
+
+ opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+ if (!opts)
+ return ERR_PTR(-ENOMEM);
+ opts->func_inst.free_func_inst = acm_free_instance;
+ ret = gserial_alloc_line(&opts->port_num);
+ if (ret) {
+ kfree(opts);
+ return ERR_PTR(ret);
+ }
+ config_group_init_type_name(&opts->func_inst.group, "",
+ &acm_func_type);
+ return &opts->func_inst;
+}
+DECLARE_USB_FUNCTION_INIT(acm, acm_alloc_instance, acm_alloc_func);
+MODULE_LICENSE("GPL");