diff options
Diffstat (limited to 'libmaple/usb/usb_cdcacm.c')
| -rw-r--r-- | libmaple/usb/usb_cdcacm.c | 742 |
1 files changed, 742 insertions, 0 deletions
diff --git a/libmaple/usb/usb_cdcacm.c b/libmaple/usb/usb_cdcacm.c new file mode 100644 index 0000000..1a3b4e6 --- /dev/null +++ b/libmaple/usb/usb_cdcacm.c @@ -0,0 +1,742 @@ +/****************************************************************************** + * The MIT License + * + * Copyright (c) 2011 LeafLabs LLC. + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + *****************************************************************************/ + +/** + * @file usb_cdcacm.c + * + * @brief USB CDC ACM (a.k.a. virtual serial terminal, VCOM) state and + * routines. + */ + +#include "usb_cdcacm.h" + +#include "nvic.h" + +#include "usb.h" +#include "usb_config.h" +#include "descriptors.h" +#include "usb_lib_globals.h" +#include "usb_reg_map.h" + +#include "usb_type.h" +#include "usb_core.h" +#include "usb_def.h" + +/****************************************************************************** + ****************************************************************************** + *** + *** HACK ALERT! FIXME FIXME FIXME FIXME! + *** + *** A bunch of LeafLabs-specific configuration lives in here for + *** now. This mess REALLY needs to get teased apart, with + *** appropriate pieces moved into Wirish. + *** + ****************************************************************************** + *****************************************************************************/ + +#if !(defined(BOARD_maple) || defined(BOARD_maple_RET6) || \ + defined(BOARD_maple_mini) || defined(BOARD_maple_native)) + +#warning ("Warning! USB VCOM relies on LeafLabs board-specific " \ + "configuration right now. If you want, you can pretend " \ + "you're one of our boards; i.e., #define BOARD_maple, " \ + "BOARD_maple_mini, etc. according to what matches your MCU " \ + "best." +#endif + +/* + * VCOM config + */ + +#define VCOM_ID_VENDOR 0x1EAF +#define VCOM_ID_PRODUCT 0x0004 + +#define VCOM_CTRL_EPNUM 0x00 +#define VCOM_CTRL_RX_ADDR 0x40 +#define VCOM_CTRL_TX_ADDR 0x80 +#define VCOM_CTRL_EPSIZE 0x40 + +#define VCOM_TX_ENDP 1 +#define VCOM_TX_EPNUM 0x01 +#define VCOM_TX_ADDR 0xC0 +#define VCOM_TX_EPSIZE 0x40 + +#define VCOM_NOTIFICATION_ENDP 2 +#define VCOM_NOTIFICATION_EPNUM 0x02 +#define VCOM_NOTIFICATION_ADDR 0x100 +#define VCOM_NOTIFICATION_EPSIZE 0x40 + +#define VCOM_RX_ENDP 3 +#define VCOM_RX_EPNUM 0x03 +#define VCOM_RX_ADDR 0x110 +#define VCOM_RX_EPSIZE 0x40 +#define VCOM_RX_BUFLEN (VCOM_RX_EPSIZE*3) + +#define USB_DEVICE_CLASS_CDC 0x02 +#define USB_DEVICE_SUBCLASS_CDC 0x00 + +#define SET_LINE_CODING 0x20 +#define GET_LINE_CODING 0x21 +#define SET_COMM_FEATURE 0x02 +#define SET_CONTROL_LINE_STATE 0x22 +#define CONTROL_LINE_DTR (0x01) +#define CONTROL_LINE_RTS (0x02) + +typedef struct { + uint32 bitrate; + uint8 format; + uint8 paritytype; + uint8 datatype; +} USB_Line_Coding; + +typedef enum { + DTR_UNSET, + DTR_HIGH, + DTR_NEGEDGE, + DTR_LOW +} RESET_STATE; + +const USB_Descriptor_Device usbVcomDescriptor_Device = { + .bLength = sizeof(USB_Descriptor_Device), + .bDescriptorType = USB_DESCRIPTOR_TYPE_DEVICE, + .bcdUSB = 0x0200, + .bDeviceClass = USB_DEVICE_CLASS_CDC, + .bDeviceSubClass = USB_DEVICE_SUBCLASS_CDC, + .bDeviceProtocol = 0x00, + .bMaxPacketSize0 = 0x40, + .idVendor = VCOM_ID_VENDOR, + .idProduct = VCOM_ID_PRODUCT, + .bcdDevice = 0x0200, + .iManufacturer = 0x01, + .iProduct = 0x02, + .iSerialNumber = 0x00, + .bNumConfigurations = 0x01, +}; + +const USB_Descriptor_Config usbVcomDescriptor_Config = { + .Config_Header = { + .bLength = sizeof(USB_Descriptor_Config_Header), + .bDescriptorType = USB_DESCRIPTOR_TYPE_CONFIGURATION, + .wTotalLength = sizeof(USB_Descriptor_Config), + .bNumInterfaces = 0x02, + .bConfigurationValue = 0x01, + .iConfiguration = 0x00, + .bmAttributes = (USB_CONFIG_ATTR_BUSPOWERED | + USB_CONFIG_ATTR_SELF_POWERED), + .bMaxPower = USB_CONFIG_MAX_POWER, + }, + + .CCI_Interface = { + .bLength = sizeof(USB_Descriptor_Interface), + .bDescriptorType = USB_DESCRIPTOR_TYPE_INTERFACE, + .bInterfaceNumber = 0x00, + .bAlternateSetting = 0x00, + .bNumEndpoints = 0x01, + .bInterfaceClass = USB_INTERFACE_CLASS_CDC, + .bInterfaceSubClass = USB_INTERFACE_SUBCLASS_CDC_ACM, + .bInterfaceProtocol = 0x01, /* Common AT Commands */ + .iInterface = 0x00, + }, + + .CDC_Functional_IntHeader = { + .bLength = CDC_FUNCTIONAL_DESCRIPTOR_SIZE(2), + .bDescriptorType = 0x24, + .SubType = 0x00, + .Data = {0x01, 0x10}, + }, + + .CDC_Functional_CallManagement = { + .bLength = CDC_FUNCTIONAL_DESCRIPTOR_SIZE(2), + .bDescriptorType = 0x24, + .SubType = 0x01, + .Data = {0x03, 0x01}, + }, + + .CDC_Functional_ACM = { + .bLength = CDC_FUNCTIONAL_DESCRIPTOR_SIZE(1), + .bDescriptorType = 0x24, + .SubType = 0x02, + .Data = {0x06}, + }, + + .CDC_Functional_Union = { + .bLength = CDC_FUNCTIONAL_DESCRIPTOR_SIZE(2), + .bDescriptorType = 0x24, + .SubType = 0x06, + .Data = {0x00, 0x01}, + }, + + .ManagementEndpoint = { + .bLength = sizeof(USB_Descriptor_Endpoint), + .bDescriptorType = USB_DESCRIPTOR_TYPE_ENDPOINT, + .bEndpointAddress = (USB_DESCRIPTOR_ENDPOINT_IN | + VCOM_NOTIFICATION_EPNUM), + .bmAttributes = EP_TYPE_INTERRUPT, + .wMaxPacketSize = VCOM_NOTIFICATION_EPSIZE, + .bInterval = 0xFF, + }, + + .DCI_Interface = { + .bLength = sizeof(USB_Descriptor_Interface), + .bDescriptorType = USB_DESCRIPTOR_TYPE_INTERFACE, + .bInterfaceNumber = 0x01, + .bAlternateSetting = 0x00, + .bNumEndpoints = 0x02, + .bInterfaceClass = USB_INTERFACE_CLASS_DIC, + .bInterfaceSubClass = 0x00, /* None */ + .bInterfaceProtocol = 0x00, /* None */ + .iInterface = 0x00, + }, + + .DataOutEndpoint = { + .bLength = sizeof(USB_Descriptor_Endpoint), + .bDescriptorType = USB_DESCRIPTOR_TYPE_ENDPOINT, + .bEndpointAddress = (USB_DESCRIPTOR_ENDPOINT_OUT | VCOM_RX_EPNUM), + .bmAttributes = EP_TYPE_BULK, + .wMaxPacketSize = VCOM_RX_EPSIZE, + .bInterval = 0x00, + }, + + .DataInEndpoint = { + .bLength = sizeof(USB_Descriptor_Endpoint), + .bDescriptorType = USB_DESCRIPTOR_TYPE_ENDPOINT, + .bEndpointAddress = (USB_DESCRIPTOR_ENDPOINT_IN | VCOM_TX_EPNUM), + .bmAttributes = EP_TYPE_BULK, + .wMaxPacketSize = VCOM_TX_EPSIZE, + .bInterval = 0x00, + }, +}; + +/* + String Identifiers: + + we may choose to specify any or none of the following string + identifiers: + + iManufacturer: LeafLabs + iProduct: Maple + iSerialNumber: NONE + iConfiguration: NONE + iInterface(CCI): NONE + iInterface(DCI): NONE + + additionally we must provide the unicode language identifier, + which is 0x0409 for US English +*/ + +const uint8 usbVcomDescriptor_LangID[USB_DESCRIPTOR_STRING_LEN(1)] = { + USB_DESCRIPTOR_STRING_LEN(1), + USB_DESCRIPTOR_TYPE_STRING, + 0x09, + 0x04, +}; + +const uint8 usbVcomDescriptor_iManufacturer[USB_DESCRIPTOR_STRING_LEN(8)] = { + USB_DESCRIPTOR_STRING_LEN(8), + USB_DESCRIPTOR_TYPE_STRING, + 'L', 0, 'e', 0, 'a', 0, 'f', 0, + 'L', 0, 'a', 0, 'b', 0, 's', 0, +}; + +const uint8 usbVcomDescriptor_iProduct[USB_DESCRIPTOR_STRING_LEN(8)] = { + USB_DESCRIPTOR_STRING_LEN(8), + USB_DESCRIPTOR_TYPE_STRING, + 'M', 0, 'a', 0, 'p', 0, 'l', 0, + 'e', 0, ' ', 0, ' ', 0, ' ', 0 +}; + +ONE_DESCRIPTOR Device_Descriptor = { + (uint8*)&usbVcomDescriptor_Device, + sizeof(USB_Descriptor_Device) +}; + +ONE_DESCRIPTOR Config_Descriptor = { + (uint8*)&usbVcomDescriptor_Config, + sizeof(USB_Descriptor_Config) +}; + +ONE_DESCRIPTOR String_Descriptor[3] = { + {(uint8*)&usbVcomDescriptor_LangID, USB_DESCRIPTOR_STRING_LEN(1)}, + {(uint8*)&usbVcomDescriptor_iManufacturer,USB_DESCRIPTOR_STRING_LEN(8)}, + {(uint8*)&usbVcomDescriptor_iProduct, USB_DESCRIPTOR_STRING_LEN(8)} +}; + +uint8 last_request = 0; + +USB_Line_Coding line_coding = { + .bitrate = 115200, + .format = 0x00, /* stop bits-1 */ + .paritytype = 0x00, + .datatype = 0x08 +}; + +uint8 vcomBufferRx[VCOM_RX_BUFLEN]; +volatile uint32 countTx = 0; +volatile uint32 recvBufIn = 0; +volatile uint32 recvBufOut = 0; +volatile uint32 maxNewBytes = VCOM_RX_BUFLEN; +volatile uint32 newBytes = 0; +RESET_STATE reset_state = DTR_UNSET; +uint8 line_dtr_rts = 0; + +/* + * VCOM callbacks + */ + +void vcomDataTxCb(void) { + /* assumes tx transactions are atomic 64 bytes (nearly certain they are) */ + countTx = 0; +} + +#define EXC_RETURN 0xFFFFFFF9 +#define DEFAULT_CPSR 0x61000000 +void vcomDataRxCb(void) { + /* FIXME this is mad buggy */ + + /* setEPRxCount on the previous cycle should garuntee + we havnt received more bytes than we can fit */ + newBytes = usb_get_ep_rx_count(VCOM_RX_ENDP); + usb_set_ep_rx_stat(VCOM_RX_ENDP, USB_EP_STAT_RX_NAK); + + /* magic number, {0x31, 0x45, 0x41, 0x46} is "1EAF" */ + uint8 chkBuf[4]; + uint8 cmpBuf[4] = {0x31, 0x45, 0x41, 0x46}; + if (reset_state == DTR_NEGEDGE) { + reset_state = DTR_LOW; + + if (newBytes >= 4) { + unsigned int target = (unsigned int)usbWaitReset | 0x1; + + usb_copy_from_pma(chkBuf, 4, VCOM_RX_ADDR); + + int i; + USB_Bool cmpMatch = TRUE; + for (i = 0; i < 4; i++) { + if (chkBuf[i] != cmpBuf[i]) { + cmpMatch = FALSE; + } + } + + if (cmpMatch) { + asm volatile("mov r0, %[stack_top] \n\t" // Reset stack + "mov sp, r0 \n\t" + "mov r0, #1 \n\t" + "mov r1, %[target_addr] \n\t" + "mov r2, %[cpsr] \n\t" + "push {r2} \n\t" // Fake xPSR + "push {r1} \n\t" // PC target addr + "push {r0} \n\t" // Fake LR + "push {r0} \n\t" // Fake R12 + "push {r0} \n\t" // Fake R3 + "push {r0} \n\t" // Fake R2 + "push {r0} \n\t" // Fake R1 + "push {r0} \n\t" // Fake R0 + "mov lr, %[exc_return] \n\t" + "bx lr" + : + : [stack_top] "r" (STACK_TOP), + [target_addr] "r" (target), + [exc_return] "r" (EXC_RETURN), + [cpsr] "r" (DEFAULT_CPSR) + : "r0", "r1", "r2"); + /* should never get here */ + } + } + } + + usb_copy_from_pma(vcomBufferRx, newBytes, VCOM_RX_ADDR); +} + +void vcomManagementCb(void) { + /* unused. This enpoint would callback if we had sent a linestate + changed notification */ +} + +u8* vcomGetSetLineCoding(uint16 length) { + if (length == 0) { + pInformation->Ctrl_Info.Usb_wLength = sizeof(USB_Line_Coding); + } + return (uint8*)&line_coding; +} + +void vcomSetLineState(void) { +} + +RESULT usbPowerOn(void) { + USB_BASE->CNTR = USB_CNTR_FRES; + + wInterrupt_Mask = 0; + USB_BASE->CNTR = wInterrupt_Mask; + USB_BASE->ISTR = 0; + wInterrupt_Mask = USB_CNTR_RESETM | USB_CNTR_SUSPM | USB_CNTR_WKUPM; + USB_BASE->CNTR = wInterrupt_Mask; + + return USB_SUCCESS; +} + +void usbInit(void) { + pInformation->Current_Configuration = 0; + usbPowerOn(); + + USB_BASE->ISTR = 0; + wInterrupt_Mask = ISR_MSK; + USB_BASE->CNTR = wInterrupt_Mask; + + nvic_irq_enable(NVIC_USB_LP_CAN_RX0); + bDeviceState = UNCONNECTED; +} + +void usbReset(void) { + pInformation->Current_Configuration = 0; + + /* current feature is current bmAttributes */ + pInformation->Current_Feature = (USB_CONFIG_ATTR_BUSPOWERED | + USB_CONFIG_ATTR_SELF_POWERED); + + USB_BASE->BTABLE = USB_BTABLE_ADDRESS; + + /* setup control endpoint 0 */ + usb_set_ep_type(USB_EP0, USB_EP_EP_TYPE_CONTROL); + usb_set_ep_tx_stat(USB_EP0, USB_EP_STAT_TX_STALL); + usb_set_ep_rx_addr(USB_EP0, VCOM_CTRL_RX_ADDR); + usb_set_ep_tx_addr(USB_EP0, VCOM_CTRL_TX_ADDR); + usb_clear_status_out(USB_EP0); + + usb_set_ep_rx_count(USB_EP0, pProperty->MaxPacketSize); + usb_set_ep_rx_stat(USB_EP0, USB_EP_STAT_RX_VALID); + + /* setup management endpoint 1 */ + usb_set_ep_type(VCOM_NOTIFICATION_ENDP, USB_EP_EP_TYPE_INTERRUPT); + usb_set_ep_tx_addr(VCOM_NOTIFICATION_ENDP, VCOM_NOTIFICATION_ADDR); + usb_set_ep_tx_stat(VCOM_NOTIFICATION_ENDP, USB_EP_STAT_TX_NAK); + usb_set_ep_rx_stat(VCOM_NOTIFICATION_ENDP, USB_EP_STAT_RX_DISABLED); + + /* TODO figure out differences in style between RX/TX EP setup */ + + /* set up data endpoint OUT (RX) */ + usb_set_ep_type(VCOM_RX_ENDP, USB_EP_EP_TYPE_BULK); + usb_set_ep_rx_addr(VCOM_RX_ENDP, 0x110); + usb_set_ep_rx_count(VCOM_RX_ENDP, 64); + usb_set_ep_rx_stat(VCOM_RX_ENDP, USB_EP_STAT_RX_VALID); + + /* set up data endpoint IN (TX) */ + usb_set_ep_type(VCOM_TX_ENDP, USB_EP_EP_TYPE_BULK); + usb_set_ep_tx_addr(VCOM_TX_ENDP, VCOM_TX_ADDR); + usb_set_ep_tx_stat(VCOM_TX_ENDP, USB_EP_STAT_TX_NAK); + usb_set_ep_rx_stat(VCOM_TX_ENDP, USB_EP_STAT_RX_DISABLED); + + bDeviceState = ATTACHED; + SetDeviceAddress(0); + + /* reset the rx fifo */ + recvBufIn = 0; + recvBufOut = 0; + maxNewBytes = VCOM_RX_EPSIZE; + countTx = 0; +} + +void usbStatusIn(void) { + /* adjust the usart line coding + if we wish to couple the CDC line coding + with the real usart port */ +} + +void usbStatusOut(void) { +} + +RESULT usbDataSetup(uint8 request) { + uint8 *(*CopyRoutine)(uint16); + CopyRoutine = NULL; + + if (Type_Recipient == (CLASS_REQUEST | INTERFACE_RECIPIENT)) { + switch (request) { + case (GET_LINE_CODING): + CopyRoutine = vcomGetSetLineCoding; + last_request = GET_LINE_CODING; + break; + case (SET_LINE_CODING): + CopyRoutine = vcomGetSetLineCoding; + last_request = SET_LINE_CODING; + break; + default: + break; + } + } + + if (CopyRoutine == NULL) { + return USB_UNSUPPORT; + } + + pInformation->Ctrl_Info.CopyData = CopyRoutine; + pInformation->Ctrl_Info.Usb_wOffset = 0; + (*CopyRoutine)(0); + return USB_SUCCESS; +} + +RESULT usbNoDataSetup(u8 request) { + uint8 new_signal; + + /* we support set com feature but dont handle it */ + if (Type_Recipient == (CLASS_REQUEST | INTERFACE_RECIPIENT)) { + + switch (request) { + case (SET_COMM_FEATURE): + return USB_SUCCESS; + case (SET_CONTROL_LINE_STATE): + /* to reset the board, pull both dtr and rts low + then pulse dtr by itself */ + new_signal = (pInformation->USBwValues.bw.bb0 & + (CONTROL_LINE_DTR | CONTROL_LINE_RTS)); + line_dtr_rts = new_signal & 0x03; + + switch (reset_state) { + /* no default, covered enum */ + case DTR_UNSET: + if ((new_signal & CONTROL_LINE_DTR) == 0 ) { + reset_state = DTR_LOW; + } else { + reset_state = DTR_HIGH; + } + break; + + case DTR_HIGH: + if ((new_signal & CONTROL_LINE_DTR) == 0 ) { + reset_state = DTR_NEGEDGE; + } else { + reset_state = DTR_HIGH; + } + break; + + case DTR_NEGEDGE: + if ((new_signal & CONTROL_LINE_DTR) == 0 ) { + reset_state = DTR_LOW; + } else { + reset_state = DTR_HIGH; + } + break; + + case DTR_LOW: + if ((new_signal & CONTROL_LINE_DTR) == 0 ) { + reset_state = DTR_LOW; + } else { + reset_state = DTR_HIGH; + } + break; + } + + return USB_SUCCESS; + } + } + return USB_UNSUPPORT; +} + +RESULT usbGetInterfaceSetting(uint8 interface, uint8 alt_setting) { + if (alt_setting > 0) { + return USB_UNSUPPORT; + } else if (interface > 1) { + return USB_UNSUPPORT; + } + + return USB_SUCCESS; +} + +u8* usbGetDeviceDescriptor(u16 length) { + return Standard_GetDescriptorData(length, &Device_Descriptor); +} + +u8* usbGetConfigDescriptor(u16 length) { + return Standard_GetDescriptorData(length, &Config_Descriptor); +} + +u8* usbGetStringDescriptor(u16 length) { + uint8 wValue0 = pInformation->USBwValue0; + + if (wValue0 > 2) { + return NULL; + } + return Standard_GetDescriptorData(length, &String_Descriptor[wValue0]); +} + +/* internal callbacks to respond to standard requests */ +void usbSetConfiguration(void) { + if (pInformation->Current_Configuration != 0) { + bDeviceState = CONFIGURED; + } +} + +void usbSetDeviceAddress(void) { + bDeviceState = ADDRESSED; +} + +/* + * Globals required by usb_lib/ + */ + +DEVICE Device_Table = + {NUM_ENDPTS, + 1}; + +DEVICE_PROP Device_Property = + {usbInit, + usbReset, + usbStatusIn, + usbStatusOut, + usbDataSetup, + usbNoDataSetup, + usbGetInterfaceSetting, + usbGetDeviceDescriptor, + usbGetConfigDescriptor, + usbGetStringDescriptor, + 0, + bMaxPacketSize}; + +USER_STANDARD_REQUESTS User_Standard_Requests = + {NOP_Process, + usbSetConfiguration, + NOP_Process, + NOP_Process, + NOP_Process, + NOP_Process, + NOP_Process, + NOP_Process, + usbSetDeviceAddress}; + +void (*pEpInt_IN[7])(void) = + {vcomDataTxCb, + vcomManagementCb, + NOP_Process, + NOP_Process, + NOP_Process, + NOP_Process, + NOP_Process}; + +void (*pEpInt_OUT[7])(void) = + {NOP_Process, + NOP_Process, + vcomDataRxCb, + NOP_Process, + NOP_Process, + NOP_Process, + NOP_Process}; + +/* + * CDC ACM routines + */ + +void usb_cdcacm_enable(gpio_dev *disc_dev, uint8 disc_bit) { + /* Present ourselves to the host */ + gpio_set_mode(disc_dev, disc_bit, GPIO_OUTPUT_PP); + gpio_write_bit(disc_dev, disc_bit, 0); // presents us to the host + + /* initialize USB peripheral */ + usb_init_usblib(&Device_Property, &User_Standard_Requests); +} + +void usb_cdcacm_disable(gpio_dev *disc_dev, uint8 disc_bit) { + // These are just guesses about how to do this, but it seems to work. + // TODO: verify this with USB spec + nvic_irq_disable(NVIC_USB_LP_CAN_RX0); + gpio_write_bit(disc_dev, disc_bit, 1); +} + +void usb_cdcacm_putc(char ch) { + while (!usb_cdcacm_tx((uint8*)&ch, 1)) + ; +} + +/* This function is non-blocking. + * + * It copies data from a usercode buffer into the USB peripheral TX + * buffer and return the number placed in that buffer. + */ +uint32 usb_cdcacm_tx(const uint8* buf, uint32 len) { + /* Last transmission hasn't finished, abort */ + if (countTx) { + return 0; + } + + // We can only put VCOM_TX_EPSIZE bytes in the buffer + /* FIXME then why are we only copying half as many? */ + if (len > VCOM_TX_EPSIZE / 2) { + len = VCOM_TX_EPSIZE / 2; + } + + // Try to load some bytes if we can + if (len) { + usb_copy_to_pma(buf, len, VCOM_TX_ADDR); + usb_set_ep_tx_count(VCOM_TX_ENDP, len); + countTx += len; + usb_set_ep_tx_stat(VCOM_TX_ENDP, USB_EP_STAT_TX_VALID); + } + + return len; +} + +/* returns the number of available bytes are in the recv FIFO */ +uint32 usb_cdcacm_data_available(void) { + return newBytes; +} + +uint16 usb_cdcacm_get_pending() { + return countTx; +} + +/* Nonblocking byte receive. + * + * Copies up to len bytes from our private data buffer (*NOT* the PMA) + * into buf and deq's the FIFO. */ +uint32 usb_cdcacm_rx(uint8* buf, uint32 len) { + static int offset = 0; + int i; + + if (len > newBytes) { + len = newBytes; + } + + for (i = 0; i < len; i++) { + buf[i] = vcomBufferRx[i + offset]; + } + + newBytes -= len; + offset += len; + + /* Re-enable the RX endpoint, which we had set to receive 0 bytes */ + if (newBytes == 0) { + usb_set_ep_rx_count(VCOM_RX_ENDP, VCOM_RX_EPSIZE); + usb_set_ep_rx_stat(VCOM_RX_ENDP, USB_EP_STAT_RX_VALID); + offset = 0; + } + + return len; +} + +uint8 usb_cdcacm_get_dtr() { + return ((line_dtr_rts & CONTROL_LINE_DTR) != 0); +} + +uint8 usb_cdcacm_get_rts() { + return ((line_dtr_rts & CONTROL_LINE_RTS) != 0); +} |