Added extra ACM interface for serial emulation using USART1.

src/stm32/cdcacm.c

@@ -32,6 +32,7 @@
 #include <libopencm3/usb/cdc.h>
 #include <libopencm3/stm32/scb.h>
 #include <libopencm3/usb/dfu.h>
+#include <libopencm3/stm32/usart.h>
 #include <stdlib.h>
 
 #include "platform.h"
@@ -60,16 +61,16 @@ static const struct usb_device_descriptor dev = {
 /* This notification endpoint isn't implemented. According to CDC spec its 
  * optional, but its absence causes a NULL pointer dereference in Linux cdc_acm 
  * driver. */
-static const struct usb_endpoint_descriptor comm_endp[] = {{
+static const struct usb_endpoint_descriptor gdb_comm_endp[] = {{
 	.bLength = USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType = USB_DT_ENDPOINT,
-	.bEndpointAddress = 0x83,
+	.bEndpointAddress = 0x82,
 	.bmAttributes = USB_ENDPOINT_ATTR_INTERRUPT,
 	.wMaxPacketSize = 16,
 	.bInterval = 255,
 }};
 
-static const struct usb_endpoint_descriptor data_endp[] = {{
+static const struct usb_endpoint_descriptor gdb_data_endp[] = {{
 	.bLength = USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType = USB_DT_ENDPOINT,
 	.bEndpointAddress = 0x01,
@@ -79,7 +80,7 @@ static const struct usb_endpoint_descriptor data_endp[] = {{
 }, {
 	.bLength = USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType = USB_DT_ENDPOINT,
-	.bEndpointAddress = 0x82,
+	.bEndpointAddress = 0x81,
 	.bmAttributes = USB_ENDPOINT_ATTR_BULK,
 	.wMaxPacketSize = 64,
 	.bInterval = 1,
@@ -90,7 +91,7 @@ static const struct {
 	struct usb_cdc_call_management_descriptor call_mgmt;
 	struct usb_cdc_acm_descriptor acm;
 	struct usb_cdc_union_descriptor cdc_union;
-} __attribute__((packed)) cdcacm_functional_descriptors = {
+} __attribute__((packed)) gdb_cdcacm_functional_descriptors = {
 	.header = {
 		.bFunctionLength = sizeof(struct usb_cdc_header_descriptor),
 		.bDescriptorType = CS_INTERFACE,
@@ -120,7 +121,7 @@ static const struct {
 	 }
 };
 
-static const struct usb_interface_descriptor comm_iface[] = {{
+static const struct usb_interface_descriptor gdb_comm_iface[] = {{
 	.bLength = USB_DT_INTERFACE_SIZE,
 	.bDescriptorType = USB_DT_INTERFACE,
 	.bInterfaceNumber = 0,
@@ -131,13 +132,13 @@ static const struct usb_interface_descriptor comm_iface[] = {{
 	.bInterfaceProtocol = USB_CDC_PROTOCOL_AT,
 	.iInterface = 0,
 
-	.endpoint = comm_endp,
+	.endpoint = gdb_comm_endp,
 
-	.extra = &cdcacm_functional_descriptors,
+	.extra = &gdb_cdcacm_functional_descriptors,
-	.extralen = sizeof(cdcacm_functional_descriptors)
+	.extralen = sizeof(gdb_cdcacm_functional_descriptors)
 }};
 
-static const struct usb_interface_descriptor data_iface[] = {{
+static const struct usb_interface_descriptor gdb_data_iface[] = {{
 	.bLength = USB_DT_INTERFACE_SIZE,
 	.bDescriptorType = USB_DT_INTERFACE,
 	.bInterfaceNumber = 1,
@@ -148,9 +149,103 @@ static const struct usb_interface_descriptor data_iface[] = {{
 	.bInterfaceProtocol = 0,
 	.iInterface = 0,
 
-	.endpoint = data_endp,
+	.endpoint = gdb_data_endp,
 }};
 
+#ifdef INCLUDE_UART_INTERFACE
+/* Serial ACM interface */
+static const struct usb_endpoint_descriptor uart_comm_endp[] = {{
+	.bLength = USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType = USB_DT_ENDPOINT,
+	.bEndpointAddress = 0x84,
+	.bmAttributes = USB_ENDPOINT_ATTR_INTERRUPT,
+	.wMaxPacketSize = 16,
+	.bInterval = 255,
+}};
+
+static const struct usb_endpoint_descriptor uart_data_endp[] = {{
+	.bLength = USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType = USB_DT_ENDPOINT,
+	.bEndpointAddress = 0x03,
+	.bmAttributes = USB_ENDPOINT_ATTR_BULK,
+	.wMaxPacketSize = 64,
+	.bInterval = 1,
+}, {
+	.bLength = USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType = USB_DT_ENDPOINT,
+	.bEndpointAddress = 0x83,
+	.bmAttributes = USB_ENDPOINT_ATTR_BULK,
+	.wMaxPacketSize = 64,
+	.bInterval = 1,
+}};
+
+static const struct {
+	struct usb_cdc_header_descriptor header;
+	struct usb_cdc_call_management_descriptor call_mgmt;
+	struct usb_cdc_acm_descriptor acm;
+	struct usb_cdc_union_descriptor cdc_union;
+} __attribute__((packed)) uart_cdcacm_functional_descriptors = {
+	.header = {
+		.bFunctionLength = sizeof(struct usb_cdc_header_descriptor),
+		.bDescriptorType = CS_INTERFACE,
+		.bDescriptorSubtype = USB_CDC_TYPE_HEADER,
+		.bcdCDC = 0x0110,
+	},
+	.call_mgmt = {
+		.bFunctionLength = 
+			sizeof(struct usb_cdc_call_management_descriptor),
+		.bDescriptorType = CS_INTERFACE,
+		.bDescriptorSubtype = USB_CDC_TYPE_CALL_MANAGEMENT,
+		.bmCapabilities = 0,
+		.bDataInterface = 3,
+	},
+	.acm = {
+		.bFunctionLength = sizeof(struct usb_cdc_acm_descriptor),
+		.bDescriptorType = CS_INTERFACE,
+		.bDescriptorSubtype = USB_CDC_TYPE_ACM,
+		.bmCapabilities = 0,
+	},
+	.cdc_union = {
+		.bFunctionLength = sizeof(struct usb_cdc_union_descriptor),
+		.bDescriptorType = CS_INTERFACE,
+		.bDescriptorSubtype = USB_CDC_TYPE_UNION,
+		.bControlInterface = 2,
+		.bSubordinateInterface0 = 3, 
+	 }
+};
+
+static const struct usb_interface_descriptor uart_comm_iface[] = {{
+	.bLength = USB_DT_INTERFACE_SIZE,
+	.bDescriptorType = USB_DT_INTERFACE,
+	.bInterfaceNumber = 2,
+	.bAlternateSetting = 0,
+	.bNumEndpoints = 1,
+	.bInterfaceClass = USB_CLASS_CDC,
+	.bInterfaceSubClass = USB_CDC_SUBCLASS_ACM,
+	.bInterfaceProtocol = USB_CDC_PROTOCOL_AT,
+	.iInterface = 0,
+
+	.endpoint = uart_comm_endp,
+
+	.extra = &uart_cdcacm_functional_descriptors,
+	.extralen = sizeof(uart_cdcacm_functional_descriptors)
+}};
+
+static const struct usb_interface_descriptor uart_data_iface[] = {{
+	.bLength = USB_DT_INTERFACE_SIZE,
+	.bDescriptorType = USB_DT_INTERFACE,
+	.bInterfaceNumber = 3,
+	.bAlternateSetting = 0,
+	.bNumEndpoints = 2,
+	.bInterfaceClass = USB_CLASS_DATA,
+	.bInterfaceSubClass = 0,
+	.bInterfaceProtocol = 0,
+	.iInterface = 0,
+
+	.endpoint = uart_data_endp,
+}};
+#endif
+
 const struct usb_dfu_descriptor dfu_function = {
 	.bLength = sizeof(struct usb_dfu_descriptor),
 	.bDescriptorType = DFU_FUNCTIONAL,
@@ -163,7 +258,7 @@ const struct usb_dfu_descriptor dfu_function = {
 const struct usb_interface_descriptor dfu_iface = {
 	.bLength = USB_DT_INTERFACE_SIZE,
 	.bDescriptorType = USB_DT_INTERFACE,
-	.bInterfaceNumber = 2,
+	.bInterfaceNumber = 4,
 	.bAlternateSetting = 0,
 	.bNumEndpoints = 0,
 	.bInterfaceClass = 0xFE,
@@ -177,11 +272,19 @@ const struct usb_interface_descriptor dfu_iface = {
 
 static const struct usb_interface ifaces[] = {{
 	.num_altsetting = 1,
-	.altsetting = comm_iface,
+	.altsetting = gdb_comm_iface,
 }, {
 	.num_altsetting = 1,
-	.altsetting = data_iface,
+	.altsetting = gdb_data_iface,
 }, {
+#ifdef INCLUDE_UART_INTERFACE
+	.num_altsetting = 1,
+	.altsetting = uart_comm_iface,
+}, {
+	.num_altsetting = 1,
+	.altsetting = uart_data_iface,
+}, {
+#endif
 	.num_altsetting = 1,
 	.altsetting = &dfu_iface,
 }};
@@ -190,7 +293,11 @@ static const struct usb_config_descriptor config = {
 	.bLength = USB_DT_CONFIGURATION_SIZE,
 	.bDescriptorType = USB_DT_CONFIGURATION,
 	.wTotalLength = 0,
+#ifdef INCLUDE_UART_INTERFACE
+	.bNumInterfaces = 5,
+#else
 	.bNumInterfaces = 3,
+#endif
 	.bConfigurationValue = 1,
 	.iConfiguration = 0,
 	.bmAttributes = 0x80,
@@ -228,8 +335,6 @@ static int cdcacm_control_request(struct usb_setup_data *req, uint8_t **buf,
 		uint16_t *len, void (**complete)(struct usb_setup_data *req))
 {
 	(void)complete;
-	(void)buf;
-	(void)len;
 
 	switch(req->bRequest) {
 	case USB_CDC_REQ_SET_CONTROL_LINE_STATE: 
@@ -237,8 +342,45 @@ static int cdcacm_control_request(struct usb_setup_data *req, uint8_t **buf,
 		 * even though it's optional in the CDC spec, and we don't 
 		 * advertise it in the ACM functional descriptor. */
 		return 1;
+#ifdef INLCUDE_UART_INTERFACE
+	case USB_CDC_REQ_SET_LINE_CODING: {
+		if(*len < sizeof(struct usb_cdc_line_coding)) 
+			return 0;
+
+		if(req->wIndex != 2) 
+			return 0;
+
+		struct usb_cdc_line_coding *coding = *buf;
+		usart_set_baudrate(USART1, coding->dwDTERate);
+		usart_set_databits(USART1, coding->bDataBits);
+		switch(coding->bCharFormat) {
+		case 0:
+			usart_set_stopbits(USART1, USART_STOPBITS_1);
+			break;
+		case 1:
+			usart_set_stopbits(USART1, USART_STOPBITS_1_5);
+			break;
+		case 2:
+			usart_set_stopbits(USART1, USART_STOPBITS_2);
+			break;
+		}
+		switch(coding->bParityType) {
+		case 0:
+			usart_set_parity(USART1, USART_PARITY_NONE);
+			break;
+		case 1:
+			usart_set_parity(USART1, USART_PARITY_ODD);
+			break;
+		case 2:
+			usart_set_parity(USART1, USART_PARITY_EVEN);
+			break;
+		}
+
+		return 1;
+		}
+#endif
 	case DFU_DETACH:
-		if(req->wIndex == 2) {
+		if(req->wIndex == 4) {
 			*complete = dfu_detach_complete;
 			return 1;
 		}
@@ -252,13 +394,33 @@ int cdcacm_get_config(void)
 	return configured;
 }
 
+#ifdef INCLUDE_UART_INTERFACE
+static void cdcacm_data_rx_cb(u8 ep)
+{
+	(void)ep;
+
+	char buf[64];
+	int len = usbd_ep_read_packet(0x03, buf, 64);
+	for(int i = 0; i < len; i++)
+		usart_send_blocking(USART1, buf[i]);
+}
+#endif
+
 static void cdcacm_set_config(u16 wValue)
 {
 	configured = wValue;
 
+	/* GDB interface */
 	usbd_ep_setup(0x01, USB_ENDPOINT_ATTR_BULK, 64, NULL);
-	usbd_ep_setup(0x82, USB_ENDPOINT_ATTR_BULK, 64, NULL);
+	usbd_ep_setup(0x81, USB_ENDPOINT_ATTR_BULK, 64, NULL);
-	usbd_ep_setup(0x83, USB_ENDPOINT_ATTR_INTERRUPT, 16, NULL);
+	usbd_ep_setup(0x82, USB_ENDPOINT_ATTR_INTERRUPT, 16, NULL);
+
+#ifdef INCLUDE_UART_INTERFACE
+	/* Serial interface */
+	usbd_ep_setup(0x03, USB_ENDPOINT_ATTR_BULK, 64, cdcacm_data_rx_cb);
+	usbd_ep_setup(0x83, USB_ENDPOINT_ATTR_BULK, 64, NULL);
+	usbd_ep_setup(0x84, USB_ENDPOINT_ATTR_INTERRUPT, 16, NULL);
+#endif
 
 	usbd_register_control_callback(
 			USB_REQ_TYPE_CLASS | USB_REQ_TYPE_INTERFACE, 
@@ -266,11 +428,15 @@ static void cdcacm_set_config(u16 wValue)
 			cdcacm_control_request);
 }
 
+/* We need a special large control buffer for this device: */
+uint8_t usbd_control_buffer[256];
+
 void cdcacm_init(void)
 {
 	get_dev_unique_id(serial_no);
 
 	usbd_init(&stm32f103_usb_driver, &dev, &config, usb_strings);
+	usbd_set_control_buffer_size(sizeof(usbd_control_buffer));
 	usbd_register_set_config_callback(cdcacm_set_config);
 
 	nvic_enable_irq(NVIC_USB_LP_CAN_RX0_IRQ);

src/stm32/gdb_if.c

@@ -39,7 +39,7 @@ void gdb_if_putchar(unsigned char c, int flush)
 {
 	buffer_in[count_in++] = c;
 	if(flush || (count_in == VIRTUAL_COM_PORT_DATA_SIZE)) {
-		while(usbd_ep_write_packet(2, buffer_in, count_in) <= 0);
+		while(usbd_ep_write_packet(1, buffer_in, count_in) <= 0);
 		count_in = 0;
 	}
 }

src/stm32/platform.c

@@ -27,8 +27,10 @@
 #include <libopencm3/stm32/systick.h>
 #include <libopencm3/stm32/scb.h>
 #include <libopencm3/stm32/nvic.h>
+#include <libopencm3/stm32/usart.h>
 
 #include "platform.h"
+#include "jtag_scan.h"
 
 #include <ctype.h>
 
@@ -39,9 +41,9 @@ jmp_buf fatal_error_jmpbuf;
 
 void morse(const char *msg, char repeat);
 static void morse_update(void);
+static void uart_init(void);
 
-int 
+int platform_init(void)
-platform_init(void)
 {
 #ifndef LIGHT
 	rcc_clock_setup_in_hse_8mhz_out_72mhz();
@@ -79,12 +81,12 @@ platform_init(void)
 	systick_interrupt_enable();
 	systick_counter_enable();
 
+#ifdef INCLUDE_UART_INTERFACE
+	uart_init();
+#endif
 #ifndef LIGHT
 	SCB_VTOR = 0x2000;	// Relocate interrupt vector table here
 #endif
-	/* Enable IRQs */
-	nvic_enable_irq(NVIC_TIM2_IRQ);
-
 	cdcacm_init();
 
 	jtag_scan();
@@ -181,3 +183,35 @@ static void morse_update(void)
 	code >>= 1; bits--;
 }
 
+#ifdef INCLUDE_UART_INTERFACE
+void uart_init(void)
+{
+	rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_USART1EN);
+
+	/* UART1 TX to 'alternate function output push-pull' */
+	gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_2_MHZ,
+		      GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO9);
+
+	/* Setup UART parameters. */
+	usart_set_baudrate(USART1, 38400);
+	usart_set_databits(USART1, 8);
+	usart_set_stopbits(USART1, USART_STOPBITS_1);
+	usart_set_mode(USART1, USART_MODE_TX_RX);
+	usart_set_parity(USART1, USART_PARITY_NONE);
+	usart_set_flow_control(USART1, USART_FLOWCONTROL_NONE);
+
+	/* Finally enable the USART. */
+	usart_enable(USART1);
+
+	/* Enable interrupts */
+	USART1_CR1 |= USART_CR1_RXNEIE;
+	nvic_enable_irq(NVIC_USART1_IRQ);
+}
+
+void usart1_isr(void)
+{
+	char c = usart_recv(USART1);
+
+	usbd_ep_write_packet(0x83, &c, 1);
+}
+#endif

src/stm32/platform.h

@@ -30,6 +30,8 @@
 
 #include "gdb_packet.h"
 
+//#define INCLUDE_UART_INTERFACE
+
 /* Important pin mappings for STM32 implementation:
  *
  * LED0 = 	PB2	(Yellow LED : Running)