trezorhal: add cdc vcp tx

TODO: rx support
TODO: buffering
TODO: cleanup

micropython/firmware/main.c

@@ -33,19 +33,29 @@ int usb_init_all(void) {
         .configuration_str = (uint8_t *)"configuration_str",
         .interface_str     = (uint8_t *)"interface_str",
     };
-    static uint8_t rx_buffer[64];
+    static uint8_t hid_rx_buffer[64];
     static const usb_hid_info_t hid_info = {
-        .iface_num = 0,
+        .iface_num        = 0x00,
         .ep_in            = 0x81,
         .ep_out           = 0x01,
         .subclass         = 0,
         .protocol         = 0,
-        .rx_buffer = rx_buffer,
+        .rx_buffer        = hid_rx_buffer,
-        .max_packet_len = sizeof(rx_buffer),
+        .max_packet_len   = sizeof(hid_rx_buffer),
         .polling_interval = 1,
         .report_desc_len  = 34,
         .report_desc      = (uint8_t*)"\x06\x00\xff\x09\x01\xa1\x01\x09\x20\x15\x00\x26\xff\x00\x75\x08\x95\x40\x81\x02\x09\x21\x15\x00\x26\xff\x00\x75\x08\x95\x40\x91\x02\xc0",
     };
+    static const usb_vcp_info_t vcp_info = {
+        .iface_num           = 0x01,
+        .data_iface_num      = 0x02,
+        .ep_cmd              = 0x82,
+        .ep_in               = 0x83,
+        .ep_out              = 0x03,
+        .polling_interval    = 1,
+        .max_cmd_packet_len  = 8,
+        .max_data_packet_len = 64,
+    };
 
     if (0 != usb_init(&dev_info)) {
         __fatal_error("usb_init failed");
@@ -53,6 +63,9 @@ int usb_init_all(void) {
     if (0 != usb_hid_add(&hid_info)) {
         __fatal_error("usb_hid_add failed");
     }
+    if (0 != usb_vcp_add(&vcp_info)) {
+        __fatal_error("usb_vcp_add failed");
+    }
     if (0 != usb_start()) {
         __fatal_error("usb_start failed");
     }

micropython/firmware/mphalport.c

@@ -1,17 +1,15 @@
 #include "py/mphal.h"
+#include "usb.h"
 
-// void USBD_CDC_TxAlways(const uint8_t *buf, uint32_t len);
+#define VCP_IFACE         0x01
-// int USBD_CDC_Rx(uint8_t *buf, uint32_t len, uint32_t timeout);
+#define VCP_WRITE_TIMEOUT 25
 
 int mp_hal_stdin_rx_chr(void) {
     for (;;) {
-    //     byte c;
+
-    //     if (USBD_CDC_Rx(&c, 1, 0) != 0) {
-    //         return c;
-    //     }
     }
 }
 
 void mp_hal_stdout_tx_strn(const char *str, size_t len) {
-    // USBD_CDC_TxAlways((const uint8_t*)str, len);
+    usb_vcp_write_blocking(VCP_IFACE, (const uint8_t *)str, len, VCP_WRITE_TIMEOUT);
 }

micropython/trezorhal/usb.h

@@ -47,6 +47,17 @@ typedef struct __attribute__((packed)) {
     uint8_t iInterface;
 } usb_interface_descriptor_t;
 
+typedef struct __attribute__((packed)) {
+    uint8_t bLength;
+    uint8_t bDescriptorType;
+    uint8_t bFirstInterface;
+    uint8_t bInterfaceCount;
+    uint8_t bFunctionClass;
+    uint8_t bFunctionSubClass;
+    uint8_t bFunctionProtocol;
+    uint8_t iFunction;
+} usb_interface_assoc_descriptor_t;
+
 typedef struct __attribute__((packed)) {
     uint8_t bLength;
     uint8_t bDescriptorType;

micropython/trezorhal/usb_vcp-defs.h

@@ -1,23 +1,79 @@
 typedef struct __attribute__((packed)) {
-} usb_vcp_descriptor_t;
+    uint8_t bFunctionLength;
+    uint8_t bDescriptorType;
+    uint8_t bDescriptorSubtype;
+    uint16_t bcdCDC;
+} usb_vcp_header_descriptor_t;
 
 typedef struct __attribute__((packed)) {
-    usb_interface_descriptor_t iface;
+    uint8_t bFunctionLength;
-    usb_vcp_descriptor_t vcp;
+    uint8_t bDescriptorType;
+    uint8_t bDescriptorSubtype;
+    uint8_t bmCapabilities;
+    uint8_t bDataInterface;
+} usb_vcp_cm_descriptor_t;
+
+typedef struct __attribute__((packed)) {
+    uint8_t bFunctionLength;
+    uint8_t bDescriptorType;
+    uint8_t bDescriptorSubtype;
+    uint8_t bmCapabilities;
+} usb_vcp_acm_descriptor_t;
+
+typedef struct __attribute__((packed)) {
+    uint8_t bFunctionLength;
+    uint8_t bDescriptorType;
+    uint8_t bDescriptorSubtype;
+    uint8_t bControlInterface;
+    uint8_t bSubordinateInterface0;
+} usb_vcp_union_descriptor_t;
+
+typedef struct __attribute__((packed)) {
+    usb_interface_assoc_descriptor_t assoc;
+    usb_interface_descriptor_t iface_cdc;
+    usb_vcp_header_descriptor_t fheader; // Class-Specific Descriptor Header Format
+    usb_vcp_cm_descriptor_t fcm;         // Call Management Functional Descriptor
+    usb_vcp_acm_descriptor_t facm;       // Abstract Control Management Functional Descriptor
+    usb_vcp_union_descriptor_t funion;   // Union Interface Functional Descriptor
+    usb_endpoint_descriptor_t ep_cmd;
+    usb_interface_descriptor_t iface_data;
     usb_endpoint_descriptor_t ep_in;
     usb_endpoint_descriptor_t ep_out;
-    usb_endpoint_descriptor_t ep_cmd;
 } usb_vcp_descriptor_block_t;
 
 typedef struct {
-    // Interface configuration
     uint8_t iface_num;           // Address of this VCP interface
+    uint8_t data_iface_num;      // Address of data interface of the VCP interface association
+    uint8_t ep_cmd;              // Address of IN CMD endpoint (with the highest bit set)
     uint8_t ep_in;               // Address of IN endpoint (with the highest bit set)
     uint8_t ep_out;              // Address of OUT endpoint
-    uint8_t ep_cmd;     // Address of CMD endpoint
+    uint8_t polling_interval;    // In units of 1ms
+    uint8_t max_cmd_packet_len;
+    uint8_t max_data_packet_len;
 } usb_vcp_info_t;
 
+// typedef struct {
+//     uint32_t cap;
+//     uint32_t read;
+//     uint32_t write;
+//     uint8_t *buf;
+// } ring_buffer_t;
+
 typedef struct {
+    uint8_t is_connected;
+    uint8_t in_idle;
+    // uint8_t cmd_op_code;
+    // uint8_t cmd_length;
+
+    // Configuration (copied from usb_vcp_info_t on init)
+    uint8_t data_iface_num;
+    uint8_t ep_cmd;
+    uint8_t ep_in;
+    uint8_t ep_out;
+    uint8_t polling_interval;
+    uint8_t max_cmd_packet_len;
+    uint8_t max_data_packet_len;
+
     const usb_vcp_descriptor_block_t *desc_block;
 } usb_vcp_state_t;
 

micropython/trezorhal/usb_vcp-impl.h

@@ -1,6 +1,183 @@
+#define USB_LEN_ASSOC_DESC              (0x08)
+
+#define USB_DESC_TYPE_ASSOCIATION       (0x0b)
+#define USB_DESC_TYPE_HEADER            (0x00)
+#define USB_DESC_TYPE_CALL_MANAGEMENT   (0x01)
+#define USB_DESC_TYPE_ACM               (0x02)
+#define USB_DESC_TYPE_UNION             (0x06)
+
+#define USB_CDC_GET_LINE_CODING         (0x21)
+#define USB_CDC_SET_CONTROL_LINE_STATE  (0x22)
+
+// static int ring_init(ring_buffer_t *b, uint8_t *buf, size_t cap) {
+//     if (cap == 0 || (cap & (cap - 1)) != 0) {
+//         return 1; // Capacity needs to be a power of 2
+//     }
+//     b->buf = buf;
+//     b->cap = cap;
+//     b->read = 0;
+//     b->write = 0;
+//     return 0;
+// }
+
+// static inline size_t ring_length(ring_buffer_t *b) {
+//     return (b->write - b->read);
+// }
+
+// static inline int ring_empty(ring_buffer_t *b) {
+//     return ring_length(b) == 0;
+// }
+
+// static inline int ring_full(ring_buffer_t *b) {
+//     return ring_length(b) == b->cap;
+// }
+
+// uint32_t ring_read(ring_buffer_t *b, uint8_t *buf, uint32_t len) {
+//     const uint32_t mask = b->cap - 1;
+//     uint32_t i;
+//     for (i = 0; (i < len) && !ring_empty(b); i++) {
+//         buf[i] = b->buf[b->read & mask];
+//         b->read++;
+//     }
+//     return i;
+// }
+
+// uint32_t ring_write(ring_buffer_t *b, const uint8_t *buf, uint32_t len) {
+//     const uint32_t mask = b->cap - 1;
+//     uint32_t i;
+//     for (i = 0; (i < len) && !ring_full(b); i++) {
+//         b->buf[b->write & mask] = buf[i];
+//         b->write++;
+//     }
+//     return i;
+// }
+
 /* usb_vcp_add adds and configures new USB VCP interface according to
  * configuration options passed in `info`. */
 int usb_vcp_add(const usb_vcp_info_t *info) {
+
+    usb_iface_t *iface = usb_get_iface(info->iface_num);
+
+    if (iface == NULL) {
+        return 1; // Invalid interface number
+    }
+    if (iface->type != USB_IFACE_TYPE_DISABLED) {
+        return 1; // Interface is already enabled
+    }
+
+    usb_vcp_descriptor_block_t *d = usb_desc_alloc_iface(sizeof(usb_vcp_descriptor_block_t));
+
+    if (d == NULL) {
+        return 1; // Not enough space in the configuration descriptor
+    }
+
+    if ((info->ep_cmd & USB_EP_DIR_MSK) != USB_EP_DIR_IN) {
+        return 1; // CMD EP is invalid
+    }
+    if ((info->ep_in & USB_EP_DIR_MSK) != USB_EP_DIR_IN) {
+        return 1; // IN EP is invalid
+    }
+    if ((info->ep_out & USB_EP_DIR_MSK) != USB_EP_DIR_OUT) {
+        return 1; // OUT EP is invalid
+    }
+
+    // Interface association descriptor
+    d->assoc.bLength           = USB_LEN_ASSOC_DESC;
+    d->assoc.bDescriptorType   = USB_DESC_TYPE_ASSOCIATION;
+    d->assoc.bFirstInterface   = info->iface_num;
+    d->assoc.bInterfaceCount   = 2;
+    d->assoc.bFunctionClass    = 0x02; // Communication Interface Class
+    d->assoc.bFunctionSubClass = 0x02; // Abstract Control Model
+    d->assoc.bFunctionProtocol = 0x01; // Common AT commands
+    d->assoc.iFunction         = 0x00; // Index of string descriptor describing the function
+
+    // Interface descriptor
+    d->iface_cdc.bLength            = USB_LEN_IF_DESC;
+    d->iface_cdc.bDescriptorType    = USB_DESC_TYPE_INTERFACE;
+    d->iface_cdc.bInterfaceNumber   = info->iface_num;
+    d->iface_cdc.bAlternateSetting  = 0x00;
+    d->iface_cdc.bNumEndpoints      = 1;
+    d->iface_cdc.bInterfaceClass    = 0x02; // Communication Interface Class
+    d->iface_cdc.bInterfaceSubClass = 0x02; // Abstract Control Model
+    d->iface_cdc.bInterfaceProtocol = 0x01; // Common AT commands
+    d->iface_cdc.iInterface         = 0x00; // Index of string descriptor describing the interface
+
+    // Header Functional Descriptor
+    d->fheader.bFunctionLength    = sizeof(usb_vcp_header_descriptor_t);
+    d->fheader.bDescriptorType    = 0x24;   // CS_INTERFACE
+    d->fheader.bDescriptorSubtype = 0x00;   // Header Func desc
+    d->fheader.bcdCDC             = 0x1001; // Spec release number
+
+    // Call Management Functional Descriptor
+    d->fcm.bFunctionLength    = sizeof(usb_vcp_cm_descriptor_t);
+    d->fcm.bDescriptorType    = 0x24; // CS_INTERFACE
+    d->fcm.bDescriptorSubtype = 0x01; // Call Management Func desc
+    d->fcm.bmCapabilities     = 0x00; // D0+D1
+    d->fcm.bDataInterface     = info->data_iface_num;
+
+    // ACM Functional Descriptor
+    d->facm.bFunctionLength    = sizeof(usb_vcp_acm_descriptor_t);
+    d->facm.bDescriptorType    = 0x24; // CS_INTERFACE
+    d->facm.bDescriptorSubtype = 0x02; // Abstract Control Management desc
+    d->facm.bmCapabilities     = 0x02;
+
+    // Union Functional Descriptor
+    d->funion.bFunctionLength        = sizeof(usb_vcp_union_descriptor_t);
+    d->funion.bDescriptorType        = 0x24; // CS_INTERFACE
+    d->funion.bDescriptorSubtype     = 0x06; // Union Func desc
+    d->funion.bControlInterface      = info->iface_num;
+    d->funion.bSubordinateInterface0 = info->data_iface_num;
+
+    // IN CMD endpoint (control)
+    d->ep_cmd.bLength          = USB_LEN_EP_DESC;
+    d->ep_cmd.bDescriptorType  = USB_DESC_TYPE_ENDPOINT;
+    d->ep_cmd.bEndpointAddress = info->ep_cmd;
+    d->ep_cmd.bmAttributes     = USBD_EP_TYPE_INTR;
+    d->ep_cmd.wMaxPacketSize   = info->max_cmd_packet_len;
+    d->ep_cmd.bInterval        = info->polling_interval;
+
+    // Interface descriptor
+    d->iface_data.bLength            = USB_LEN_IF_DESC;
+    d->iface_data.bDescriptorType    = USB_DESC_TYPE_INTERFACE;
+    d->iface_data.bInterfaceNumber   = info->data_iface_num;
+    d->iface_data.bAlternateSetting  = 0x00;
+    d->iface_data.bNumEndpoints      = 2;
+    d->iface_data.bInterfaceClass    = 0x0A; // CDC
+    d->iface_data.bInterfaceSubClass = 0x00;
+    d->iface_data.bInterfaceProtocol = 0x00;
+    d->iface_data.iInterface         = 0x00; // Index of string descriptor describing the interface
+
+    // OUT endpoint (receiving)
+    d->ep_out.bLength          = USB_LEN_EP_DESC;
+    d->ep_out.bDescriptorType  = USB_DESC_TYPE_ENDPOINT;
+    d->ep_out.bEndpointAddress = info->ep_out;
+    d->ep_out.bmAttributes     = USBD_EP_TYPE_BULK;
+    d->ep_out.wMaxPacketSize   = info->max_data_packet_len;
+    d->ep_out.bInterval        = 0x00; // Ignored for bulk endpoints
+
+    // IN endpoint (sending)
+    d->ep_in.bLength          = USB_LEN_EP_DESC;
+    d->ep_in.bDescriptorType  = USB_DESC_TYPE_ENDPOINT;
+    d->ep_in.bEndpointAddress = info->ep_in;
+    d->ep_in.bmAttributes     = USBD_EP_TYPE_BULK;
+    d->ep_in.wMaxPacketSize   = info->max_data_packet_len;
+    d->ep_in.bInterval        = 0x00; // Ignored for bulk endpoints
+
+    // Config descriptor
+    // TODO: do this in a clean way
+    usb_desc_add_iface(sizeof(usb_vcp_descriptor_block_t));
+    usb_config_desc->bNumInterfaces++;
+
+    // Interface state
+    iface->type = USB_IFACE_TYPE_VCP;
+    iface->vcp.data_iface_num = info->data_iface_num;
+    iface->vcp.ep_cmd = info->ep_cmd;
+    iface->vcp.ep_in = info->ep_in;
+    iface->vcp.ep_out = info->ep_out;
+    iface->vcp.max_cmd_packet_len = info->max_cmd_packet_len;
+    iface->vcp.max_data_packet_len = info->max_data_packet_len;
+    iface->vcp.desc_block = d;
+
     return 0;
 }
 
@@ -9,17 +186,56 @@ int usb_vcp_can_read(uint8_t iface_num) {
 }
 
 int usb_vcp_can_write(uint8_t iface_num) {
-    return 0;
+    usb_iface_t *iface = usb_get_iface(iface_num);
+    if (iface == NULL) {
+        return 0; // Invalid interface number
+    }
+    if (iface->type != USB_IFACE_TYPE_VCP) {
+        return 0; // Invalid interface type
+    }
+    if (iface->vcp.in_idle == 0) {
+        return 0; // Last transmission is not over yet
+    }
+    if (usb_dev_handle.dev_state != USBD_STATE_CONFIGURED) {
+        return 0; // Device is not configured
+    }
+    return 1;
 }
 
 int usb_vcp_read(uint8_t iface_num, uint8_t *buf, uint32_t len) {
+    usb_iface_t *iface = usb_get_iface(iface_num);
+    if (iface == NULL) {
+        return -1; // Invalid interface number
+    }
+    if (iface->type != USB_IFACE_TYPE_VCP) {
+        return -2; // Interface interface type
+    }
+    // usb_vcp_state_t *state = &iface->vcp;
+    // TODO
+
     return 0;
 }
 
 int usb_vcp_write(uint8_t iface_num, const uint8_t *buf, uint32_t len) {
+    usb_iface_t *iface = usb_get_iface(iface_num);
+    if (iface == NULL) {
+        return -1; // Invalid interface number
+    }
+    if (iface->type != USB_IFACE_TYPE_VCP) {
+        return -2; // Interface interface type
+    }
+    usb_vcp_state_t *state = &iface->vcp;
+
+    if (!state->is_connected) {
         return 0;
     }
 
+    state->in_idle = 0;
+    USBD_LL_Transmit(&usb_dev_handle, state->ep_in, UNCONST(buf), (uint16_t)len);
+
+    return len;
+}
+
 int usb_vcp_read_blocking(uint8_t iface_num, uint8_t *buf, uint32_t len, uint32_t timeout) {
     uint32_t start = HAL_GetTick();
     while (!usb_vcp_can_read(iface_num)) {
@@ -43,21 +259,69 @@ int usb_vcp_write_blocking(uint8_t iface_num, const uint8_t *buf, uint32_t len,
 }
 
 static int usb_vcp_class_init(USBD_HandleTypeDef *dev, usb_vcp_state_t *state, uint8_t cfg_idx) {
+    // Open endpoints
+    USBD_LL_OpenEP(dev, state->ep_in, USBD_EP_TYPE_BULK, state->max_data_packet_len);
+    USBD_LL_OpenEP(dev, state->ep_out, USBD_EP_TYPE_BULK, state->max_data_packet_len);
+    USBD_LL_OpenEP(dev, state->ep_cmd, USBD_EP_TYPE_INTR, state->max_cmd_packet_len);
+
+    // Reset the state
+    state->in_idle = 1;
+
+    // TODO
+    // Prepare the OUT EP to receive next packet
+    // USBD_LL_PrepareReceive(dev, state->ep_out, state->rx_buffer, state->max_data_packet_len);
+
     return USBD_OK;
 }
 
 static int usb_vcp_class_deinit(USBD_HandleTypeDef *dev, usb_vcp_state_t *state, uint8_t cfg_idx) {
+    // Close endpoints
+    USBD_LL_CloseEP(dev, state->ep_in);
+    USBD_LL_CloseEP(dev, state->ep_out);
+    USBD_LL_CloseEP(dev, state->ep_cmd);
+
     return USBD_OK;
 }
 
 static int usb_vcp_class_setup(USBD_HandleTypeDef *dev, usb_vcp_state_t *state, USBD_SetupReqTypedef *req) {
+    static const uint8_t line_coding[] = {
+        (uint8_t)(115200 >> 0),
+        (uint8_t)(115200 >> 8),
+        (uint8_t)(115200 >> 16),
+        (uint8_t)(115200 >> 24),
+        0, // Stop bits
+        0, // Parity
+        8, // Number of bits
+    };
+
+    switch (req->bmRequest & USB_REQ_TYPE_MASK) {
+
+    // Class request
+    case USB_REQ_TYPE_CLASS :
+        switch (req->bRequest) {
+
+        case USB_CDC_GET_LINE_CODING:
+            USBD_CtlSendData(dev, UNCONST(line_coding), sizeof(line_coding));
+            break;
+
+        case USB_CDC_SET_CONTROL_LINE_STATE:
+            state->is_connected = req->wLength & 1;
+            break;
+        }
+        break;
+    }
+
     return USBD_OK;
 }
 
 static uint8_t usb_vcp_class_data_in(USBD_HandleTypeDef *dev, usb_vcp_state_t *state, uint8_t ep_num) {
+    if ((ep_num | USB_EP_DIR_IN) == state->ep_in) {
+        state->in_idle = 1;
+    }
     return USBD_OK;
 }
 
 static uint8_t usb_vcp_class_data_out(USBD_HandleTypeDef *dev, usb_vcp_state_t *state, uint8_t ep_num) {
+    // TODO: process received data
     return USBD_OK;
 }

micropython/trezorhal/usbd_conf.c

@@ -290,13 +290,10 @@ void HAL_PCD_DataInStageCallback(PCD_HandleTypeDef *hpcd, uint8_t epnum)
   * @param  hpcd: PCD handle
   * @retval None
   */
-/*
-This is now handled by the USB CDC interface.
 void HAL_PCD_SOFCallback(PCD_HandleTypeDef *hpcd)
 {
   USBD_LL_SOF(hpcd->pData);
 }
-*/
 
 /**
   * @brief  Reset callback.