1
linux/drivers/usb/gadget/function/f_acm.c
Michael Walle a17f04d4f2 usb: gadget: f_acm: make bInterfaceProtocol configurable
The bInterfaceProtocol is hardcoded to USB_CDC_ACM_PROTO_AT_V25TER. This
will lead to problems with ModemManger which will gladly try to probe
that port as a modem if the gadget also has a network function.
ModemManager will try to send AT commands to the ACM port. Make the
bInterfaceProtocol configurable. For this, track the number of instances
and only allow write to the property if there are no intances (yet).

This will also set bFunctionProtocol to the same value, see commit
5c8db070b4 ("USB: Change acm_iad_descriptor bFunctionProtocol to
USB_CDC_ACM_PROTO_AT_V25TER") for more details.

Signed-off-by: Michael Walle <mwalle@kernel.org>
Link: https://lore.kernel.org/r/20240825180446.3757073-1-mwalle@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-09-03 09:54:16 +02:00

907 lines
25 KiB
C

// 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 bInterfaceProtocol;
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 = DYNAMIC */
/* .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 = DYNAMIC */
/* .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;
acm_iad_descriptor.bFunctionProtocol = acm->bInterfaceProtocol;
acm_control_interface_desc.bInterfaceProtocol = acm->bInterfaceProtocol;
/* 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: IN/%s OUT/%s NOTIFY/%s\n",
acm->port_num,
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);
struct f_serial_opts *opts;
opts = container_of(f->fi, struct f_serial_opts, func_inst);
kfree(acm);
mutex_lock(&opts->lock);
opts->instances--;
mutex_unlock(&opts->lock);
}
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);
mutex_lock(&opts->lock);
acm->port_num = opts->port_num;
acm->bInterfaceProtocol = opts->protocol;
opts->instances++;
mutex_unlock(&opts->lock);
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 ssize_t f_acm_protocol_show(struct config_item *item, char *page)
{
return sprintf(page, "%u\n", to_f_serial_opts(item)->protocol);
}
static ssize_t f_acm_protocol_store(struct config_item *item,
const char *page, size_t count)
{
struct f_serial_opts *opts = to_f_serial_opts(item);
int ret;
mutex_lock(&opts->lock);
if (opts->instances) {
ret = -EBUSY;
goto out;
}
ret = kstrtou8(page, 0, &opts->protocol);
if (ret)
goto out;
ret = count;
out:
mutex_unlock(&opts->lock);
return ret;
}
CONFIGFS_ATTR(f_acm_, protocol);
static struct configfs_attribute *acm_attrs[] = {
#ifdef CONFIG_U_SERIAL_CONSOLE
&f_acm_attr_console,
#endif
&f_acm_attr_port_num,
&f_acm_attr_protocol,
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);
mutex_destroy(&opts->lock);
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->protocol = USB_CDC_ACM_PROTO_AT_V25TER;
opts->func_inst.free_func_inst = acm_free_instance;
mutex_init(&opts->lock);
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_DESCRIPTION("USB CDC serial (ACM) function driver");
MODULE_LICENSE("GPL");