blob: b2ddd1ada8bac668275240e0e5b935a79c743dc1 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* 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
* Copyright (c) 2021, Linaro Ltd <loic.poulain@linaro.org>
*/
#include <circbuf.h>
#include <common.h>
#include <console.h>
#include <errno.h>
#include <g_dnl.h>
#include <malloc.h>
#include <memalign.h>
#include <stdio_dev.h>
#include <version.h>
#include <watchdog.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <linux/usb/composite.h>
#include <linux/usb/cdc.h>
#define REQ_SIZE_MAX 512
struct f_acm {
int ctrl_id;
int data_id;
struct usb_ep *ep_in;
struct usb_ep *ep_out;
struct usb_ep *ep_notify;
struct usb_request *req_in;
struct usb_request *req_out;
bool connected;
bool tx_on;
circbuf_t rx_buf;
circbuf_t tx_buf;
struct usb_function usb_function;
struct usb_cdc_line_coding line_coding;
u16 handshake_bits;
#define ACM_CTRL_RTS BIT(1) /* unused with full duplex */
#define ACM_CTRL_DTR BIT(0) /* host is ready for data r/w */
int controller_index;
};
static struct f_acm *default_acm_function;
static inline struct f_acm *func_to_acm(struct usb_function *f)
{
return container_of(f, struct f_acm, usb_function);
}
static inline struct f_acm *stdio_to_acm(struct stdio_dev *s)
{
/* stdio dev is cloned on registration, do not use container_of */
return s->priv;
}
static struct usb_interface_assoc_descriptor
acm_iad_descriptor = {
.bLength = sizeof(acm_iad_descriptor),
.bDescriptorType = USB_DT_INTERFACE_ASSOCIATION,
.bFirstInterface = 0,
.bInterfaceCount = 2, // control + data
.bFunctionClass = USB_CLASS_COMM,
.bFunctionSubClass = USB_CDC_SUBCLASS_ACM,
.bFunctionProtocol = USB_CDC_ACM_PROTO_AT_V25TER,
};
static struct usb_interface_descriptor acm_control_intf_desc = {
.bLength = USB_DT_INTERFACE_SIZE,
.bDescriptorType = USB_DT_INTERFACE,
.bNumEndpoints = 1,
.bInterfaceClass = USB_CLASS_COMM,
.bInterfaceSubClass = USB_CDC_SUBCLASS_ACM,
.bInterfaceProtocol = USB_CDC_ACM_PROTO_AT_V25TER,
};
static struct usb_interface_descriptor acm_data_intf_desc = {
.bLength = sizeof(acm_data_intf_desc),
.bDescriptorType = USB_DT_INTERFACE,
.bNumEndpoints = 2,
.bInterfaceClass = USB_CLASS_CDC_DATA,
};
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 = __constant_cpu_to_le16(0x0110),
};
static struct usb_cdc_call_mgmt_descriptor acm_call_mgmt_desc = {
.bLength = sizeof(acm_call_mgmt_desc),
.bDescriptorType = USB_DT_CS_INTERFACE,
.bDescriptorSubType = USB_CDC_CALL_MANAGEMENT_TYPE,
.bmCapabilities = 0,
.bDataInterface = 0x01,
};
static struct usb_cdc_acm_descriptor acm_desc = {
.bLength = sizeof(acm_desc),
.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 = 0x00,
.bSlaveInterface0 = 0x01,
};
static struct usb_endpoint_descriptor acm_fs_notify_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 3 | USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = __constant_cpu_to_le16(64),
.bInterval = 32,
};
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_intf_desc,
(struct usb_descriptor_header *)&acm_header_desc,
(struct usb_descriptor_header *)&acm_call_mgmt_desc,
(struct usb_descriptor_header *)&acm_desc,
(struct usb_descriptor_header *)&acm_union_desc,
(struct usb_descriptor_header *)&acm_fs_notify_desc,
(struct usb_descriptor_header *)&acm_data_intf_desc,
(struct usb_descriptor_header *)&acm_fs_in_desc,
(struct usb_descriptor_header *)&acm_fs_out_desc,
NULL,
};
static struct usb_endpoint_descriptor acm_hs_notify_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = __constant_cpu_to_le16(64),
.bInterval = 11,
};
static struct usb_endpoint_descriptor acm_hs_in_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = __constant_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 = __constant_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_intf_desc,
(struct usb_descriptor_header *)&acm_header_desc,
(struct usb_descriptor_header *)&acm_call_mgmt_desc,
(struct usb_descriptor_header *)&acm_desc,
(struct usb_descriptor_header *)&acm_union_desc,
(struct usb_descriptor_header *)&acm_hs_notify_desc,
(struct usb_descriptor_header *)&acm_data_intf_desc,
(struct usb_descriptor_header *)&acm_hs_in_desc,
(struct usb_descriptor_header *)&acm_hs_out_desc,
NULL,
};
static inline struct usb_endpoint_descriptor *
ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *hs,
struct usb_endpoint_descriptor *fs)
{
if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
return hs;
return fs;
}
static int acm_bind(struct usb_configuration *c, struct usb_function *f)
{
struct usb_gadget *gadget = c->cdev->gadget;
struct f_acm *f_acm = func_to_acm(f);
struct usb_ep *ep;
int id;
id = usb_interface_id(c, f);
if (id < 0)
return id;
acm_iad_descriptor.bFirstInterface = id;
acm_control_intf_desc.bInterfaceNumber = id;
acm_union_desc.bMasterInterface0 = id;
f_acm->ctrl_id = id;
id = usb_interface_id(c, f);
if (id < 0)
return id;
acm_data_intf_desc.bInterfaceNumber = id;
acm_union_desc.bSlaveInterface0 = id;
acm_call_mgmt_desc.bDataInterface = id;
f_acm->data_id = id;
/* allocate instance-specific endpoints */
ep = usb_ep_autoconfig(gadget, &acm_fs_in_desc);
if (!ep)
return -ENODEV;
f_acm->ep_in = ep;
ep = usb_ep_autoconfig(gadget, &acm_fs_out_desc);
if (!ep)
return -ENODEV;
f_acm->ep_out = ep;
ep = usb_ep_autoconfig(gadget, &acm_fs_notify_desc);
if (!ep)
return -ENODEV;
f_acm->ep_notify = ep;
if (gadget_is_dualspeed(gadget)) {
/* Assume endpoint addresses are the same for 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;
}
return 0;
}
static void acm_unbind(struct usb_configuration *c, struct usb_function *f)
{
struct f_acm *f_acm = func_to_acm(f);
if (default_acm_function == f_acm)
default_acm_function = NULL;
buf_free(&f_acm->rx_buf);
buf_free(&f_acm->tx_buf);
free(f_acm);
}
static void acm_notify_complete(struct usb_ep *ep, struct usb_request *req)
{
/* nothing to do */
}
static void acm_tx_complete(struct usb_ep *ep, struct usb_request *req)
{
struct f_acm *f_acm = req->context;
f_acm->tx_on = true;
}
static void acm_rx_complete(struct usb_ep *ep, struct usb_request *req)
{
struct f_acm *f_acm = req->context;
buf_push(&f_acm->rx_buf, req->buf, req->actual);
/* Queue RX req again */
req->actual = 0;
usb_ep_queue(ep, req, 0);
}
static struct usb_request *acm_start_ep(struct usb_ep *ep, void *complete_cb,
void *context)
{
struct usb_request *req;
req = usb_ep_alloc_request(ep, 0);
if (!req)
return NULL;
req->length = REQ_SIZE_MAX;
req->buf = memalign(CONFIG_SYS_CACHELINE_SIZE, REQ_SIZE_MAX);
if (!req->buf) {
usb_ep_free_request(ep, req);
return NULL;
}
memset(req->buf, 0, req->length);
req->complete = complete_cb;
req->context = context;
return req;
}
static int acm_start_data(struct f_acm *f_acm, struct usb_gadget *gadget)
{
const struct usb_endpoint_descriptor *d;
int ret;
/* EP IN */
d = ep_desc(gadget, &acm_hs_in_desc, &acm_fs_in_desc);
ret = usb_ep_enable(f_acm->ep_in, d);
if (ret)
return ret;
f_acm->req_in = acm_start_ep(f_acm->ep_in, acm_tx_complete, f_acm);
/* EP OUT */
d = ep_desc(gadget, &acm_hs_out_desc, &acm_fs_out_desc);
ret = usb_ep_enable(f_acm->ep_out, d);
if (ret)
return ret;
f_acm->req_out = acm_start_ep(f_acm->ep_out, acm_rx_complete, f_acm);
/* Start OUT transfer (EP OUT) */
ret = usb_ep_queue(f_acm->ep_out, f_acm->req_out, 0);
if (ret)
return ret;
return 0;
}
static int acm_start_ctrl(struct f_acm *f_acm, struct usb_gadget *gadget)
{
const struct usb_endpoint_descriptor *d;
usb_ep_disable(f_acm->ep_notify);
d = ep_desc(gadget, &acm_hs_notify_desc, &acm_fs_notify_desc);
usb_ep_enable(f_acm->ep_notify, d);
acm_start_ep(f_acm->ep_notify, acm_notify_complete, f_acm);
return 0;
}
static int acm_set_alt(struct usb_function *f, unsigned int intf, unsigned int alt)
{
struct usb_gadget *gadget = f->config->cdev->gadget;
struct f_acm *f_acm = func_to_acm(f);
if (intf == f_acm->ctrl_id) {
return acm_start_ctrl(f_acm, gadget);
} else if (intf == f_acm->data_id) {
acm_start_data(f_acm, gadget);
f_acm->connected = true;
f_acm->tx_on = true;
return 0;
}
return -EINVAL;
}
static int acm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
{
struct usb_gadget *gadget = f->config->cdev->gadget;
struct usb_request *req = f->config->cdev->req;
u16 w_index = le16_to_cpu(ctrl->wIndex);
u16 w_value = le16_to_cpu(ctrl->wValue);
u16 w_length = le16_to_cpu(ctrl->wLength);
struct f_acm *f_acm = func_to_acm(f);
int value = -1;
switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
| USB_CDC_REQ_SET_LINE_CODING:
/* SET_LINE_CODING */
if (w_length != sizeof(f_acm->line_coding) || w_index != f_acm->ctrl_id)
goto invalid;
value = w_length;
memcpy(&f_acm->line_coding, req->buf, value);
break;
case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
| USB_CDC_REQ_GET_LINE_CODING:
/* GET_LINE_CODING */
if (w_length != sizeof(f_acm->line_coding) || w_index != f_acm->ctrl_id)
goto invalid;
value = w_length;
memcpy(req->buf, &f_acm->line_coding, value);
break;
case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
| USB_CDC_REQ_SET_CONTROL_LINE_STATE:
/* SET_CONTROL_LINE_STATE */
if (w_index != f_acm->ctrl_id)
goto invalid;
value = 0;
f_acm->handshake_bits = w_value;
break;
default:
invalid:
printf("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) {
req->zero = 0;
req->length = value;
usb_ep_queue(gadget->ep0, req, GFP_ATOMIC);
}
return 0;
}
static void acm_disable(struct usb_function *f)
{
struct f_acm *f_acm = func_to_acm(f);
usb_ep_disable(f_acm->ep_out);
usb_ep_disable(f_acm->ep_in);
usb_ep_disable(f_acm->ep_notify);
if (f_acm->req_out) {
free(f_acm->req_out->buf);
usb_ep_free_request(f_acm->ep_out, f_acm->req_out);
f_acm->req_out = NULL;
}
if (f_acm->req_in) {
free(f_acm->req_in->buf);
usb_ep_free_request(f_acm->ep_in, f_acm->req_in);
f_acm->req_in = NULL;
}
}
/* static strings, in UTF-8 */
static struct usb_string acm_string_defs[] = {
[0].s = "CDC Abstract Control Model (ACM)",
[1].s = "CDC ACM Data",
[2].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,
};
static void __acm_tx(struct f_acm *f_acm)
{
int len, ret;
do {
usb_gadget_handle_interrupts(f_acm->controller_index);
if (!(f_acm->handshake_bits & ACM_CTRL_DTR))
break;
if (!f_acm->tx_on)
continue;
len = buf_pop(&f_acm->tx_buf, f_acm->req_in->buf, REQ_SIZE_MAX);
if (!len)
break;
f_acm->req_in->length = len;
ret = usb_ep_queue(f_acm->ep_in, f_acm->req_in, 0);
if (ret)
break;
f_acm->tx_on = false;
/* Do not reset the watchdog, if TX is stuck there is probably
* a real issue.
*/
} while (1);
}
static bool acm_connected(struct stdio_dev *dev)
{
struct f_acm *f_acm = stdio_to_acm(dev);
/* give a chance to process udc irq */
usb_gadget_handle_interrupts(f_acm->controller_index);
return f_acm->connected;
}
static int acm_add(struct usb_configuration *c)
{
struct f_acm *f_acm;
int status;
f_acm = calloc(1, sizeof(*f_acm));
if (!f_acm)
return -ENOMEM;
f_acm->usb_function.name = "f_acm";
f_acm->usb_function.bind = acm_bind;
f_acm->usb_function.unbind = acm_unbind;
f_acm->usb_function.set_alt = acm_set_alt;
f_acm->usb_function.disable = acm_disable;
f_acm->usb_function.strings = acm_strings;
f_acm->usb_function.descriptors = acm_fs_function;
f_acm->usb_function.hs_descriptors = acm_hs_function;
f_acm->usb_function.setup = acm_setup;
f_acm->controller_index = 0;
status = usb_add_function(c, &f_acm->usb_function);
if (status) {
free(f_acm);
return status;
}
buf_init(&f_acm->rx_buf, 2048);
buf_init(&f_acm->tx_buf, 2048);
if (!default_acm_function)
default_acm_function = f_acm;
return status;
}
DECLARE_GADGET_BIND_CALLBACK(usb_serial_acm, acm_add);
/* STDIO */
static int acm_stdio_tstc(struct stdio_dev *dev)
{
struct f_acm *f_acm = stdio_to_acm(dev);
usb_gadget_handle_interrupts(f_acm->controller_index);
return (f_acm->rx_buf.size > 0);
}
static int acm_stdio_getc(struct stdio_dev *dev)
{
struct f_acm *f_acm = stdio_to_acm(dev);
char c;
/* Wait for a character to arrive. */
while (!acm_stdio_tstc(dev))
schedule();
buf_pop(&f_acm->rx_buf, &c, 1);
return c;
}
static void acm_stdio_putc(struct stdio_dev *dev, const char c)
{
struct f_acm *f_acm = stdio_to_acm(dev);
if (c == '\n')
buf_push(&f_acm->tx_buf, "\r", 1);
buf_push(&f_acm->tx_buf, &c, 1);
if (!f_acm->connected)
return;
__acm_tx(f_acm);
}
static void acm_stdio_puts(struct stdio_dev *dev, const char *str)
{
struct f_acm *f_acm = stdio_to_acm(dev);
while (*str) {
if (*str == '\n')
buf_push(&f_acm->tx_buf, "\r", 1);
buf_push(&f_acm->tx_buf, str++, 1);
}
if (!f_acm->connected)
return;
__acm_tx(f_acm);
}
static int acm_stdio_start(struct stdio_dev *dev)
{
int ret;
if (dev->priv) { /* function already exist */
return 0;
}
ret = g_dnl_register("usb_serial_acm");
if (ret)
return ret;
if (default_acm_function)
dev->priv = default_acm_function;
else
return -ENODEV;
while (!acm_connected(dev)) {
if (ctrlc())
return -ECANCELED;
schedule();
}
return 0;
}
static int acm_stdio_stop(struct stdio_dev *dev)
{
g_dnl_unregister();
g_dnl_clear_detach();
return 0;
}
int drv_usbacm_init(void)
{
struct stdio_dev stdio;
strcpy(stdio.name, "usbacm");
stdio.flags = DEV_FLAGS_INPUT | DEV_FLAGS_OUTPUT;
stdio.tstc = acm_stdio_tstc;
stdio.getc = acm_stdio_getc;
stdio.putc = acm_stdio_putc;
stdio.puts = acm_stdio_puts;
stdio.start = acm_stdio_start;
stdio.stop = acm_stdio_stop;
stdio.priv = NULL;
stdio.ext = 0;
return stdio_register(&stdio);
}