--- /dev/null
+// 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))
+ WATCHDOG_RESET();
+
+ 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;
+
+ WATCHDOG_RESET();
+ }
+
+ 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);
+}
projects / u-boot.git / commitdiff
