comm_usb_serial.c

// NOTE: this file is created from the USB_CDC testhal example

#include "ch.h"
#include "hal.h"
#include "stm32f4xx_conf.h"

/*
 * Endpoints to be used for USBD2.
 */
#define USBD2_DATA_REQUEST_EP           1
#define USBD2_DATA_AVAILABLE_EP         1
#define USBD2_INTERRUPT_REQUEST_EP      2

/*
 * Serial over USB Driver structure.
 */
SerialUSBDriver SDU1;

/*
 * USB Device Descriptor.
 */
static const uint8_t vcom_device_descriptor_data[18] = {
		USB_DESC_DEVICE       (0x0110,        /* bcdUSB (1.1).     */
				0x02,          /* bDeviceClass (CDC).              */
				0x00,          /* bDeviceSubClass.                 */
				0x00,          /* bDeviceProtocol.                 */
				0x40,          /* bMaxPacketSize.                  */
				0x0483,        /* idVendor (ST).                   */
				0x5740,        /* idProduct.                       */
				0x0200,        /* bcdDevice.                       */
				1,             /* iManufacturer.                   */
				2,             /* iProduct.                        */
				3,             /* iSerialNumber.                   */
				1)             /* bNumConfigurations.              */
};

/*
 * Device Descriptor wrapper.
 */
static const USBDescriptor vcom_device_descriptor = {
		sizeof vcom_device_descriptor_data,
		vcom_device_descriptor_data
};

/* Configuration Descriptor tree for a CDC.*/
static const uint8_t vcom_configuration_descriptor_data[67] = {
		/* Configuration Descriptor.*/
		USB_DESC_CONFIGURATION(67,            /* wTotalLength.                    */
				0x02,          /* bNumInterfaces.                  */
				0x01,          /* bConfigurationValue.             */
				0,             /* iConfiguration.                  */
				0xC0,          /* bmAttributes (self powered).     */
				50),           /* bMaxPower (100mA).               */
				/* Interface Descriptor.*/
				USB_DESC_INTERFACE    (0x00,          /* bInterfaceNumber.                */
						0x00,          /* bAlternateSetting.               */
						0x01,          /* bNumEndpoints.                   */
						0x02,          /* bInterfaceClass (Communications
                                           Interface Class, CDC section
                                           4.2).                            */
						0x02,          /* bInterfaceSubClass (Abstract
                                         Control Model, CDC section 4.3).   */
						0x01,          /* bInterfaceProtocol (AT commands,
                                           CDC section 4.4).                */
						0),            /* iInterface.                      */
						/* Header Functional Descriptor (CDC section 5.2.3).*/
						USB_DESC_BYTE         (5),            /* bLength.                         */
						USB_DESC_BYTE         (0x24),         /* bDescriptorType (CS_INTERFACE).  */
						USB_DESC_BYTE         (0x00),         /* bDescriptorSubtype (Header
                                           Functional Descriptor.           */
						USB_DESC_BCD          (0x0110),       /* bcdCDC.                          */
						/* Call Management Functional Descriptor. */
						USB_DESC_BYTE         (5),            /* bFunctionLength.                 */
						USB_DESC_BYTE         (0x24),         /* bDescriptorType (CS_INTERFACE).  */
						USB_DESC_BYTE         (0x01),         /* bDescriptorSubtype (Call Management
                                           Functional Descriptor).          */
						USB_DESC_BYTE         (0x00),         /* bmCapabilities (D0+D1).          */
						USB_DESC_BYTE         (0x01),         /* bDataInterface.                  */
						/* ACM Functional Descriptor.*/
						USB_DESC_BYTE         (4),            /* bFunctionLength.                 */
						USB_DESC_BYTE         (0x24),         /* bDescriptorType (CS_INTERFACE).  */
						USB_DESC_BYTE         (0x02),         /* bDescriptorSubtype (Abstract
                                           Control Management Descriptor).  */
						USB_DESC_BYTE         (0x02),         /* bmCapabilities.                  */
						/* Union Functional Descriptor.*/
						USB_DESC_BYTE         (5),            /* bFunctionLength.                 */
						USB_DESC_BYTE         (0x24),         /* bDescriptorType (CS_INTERFACE).  */
						USB_DESC_BYTE         (0x06),         /* bDescriptorSubtype (Union
                                           Functional Descriptor).          */
						USB_DESC_BYTE         (0x00),         /* bMasterInterface (Communication
                                           Class Interface).                */
						USB_DESC_BYTE         (0x01),         /* bSlaveInterface0 (Data Class
                                           Interface).                      */
						/* Endpoint 2 Descriptor.*/
						USB_DESC_ENDPOINT     (USBD2_INTERRUPT_REQUEST_EP|0x80,
								0x03,          /* bmAttributes (Interrupt).        */
								0x0008,        /* wMaxPacketSize.                  */
								0xFF),         /* bInterval.                       */
								/* Interface Descriptor.*/
								USB_DESC_INTERFACE    (0x01,          /* bInterfaceNumber.                */
										0x00,          /* bAlternateSetting.               */
										0x02,          /* bNumEndpoints.                   */
										0x0A,          /* bInterfaceClass (Data Class
                                           Interface, CDC section 4.5).     */
										0x00,          /* bInterfaceSubClass (CDC section
                                           4.6).                            */
										0x00,          /* bInterfaceProtocol (CDC section
                                           4.7).                            */
										0x00),         /* iInterface.                      */
										/* Endpoint 3 Descriptor.*/
										USB_DESC_ENDPOINT     (USBD2_DATA_AVAILABLE_EP,       /* bEndpointAddress.*/
												0x02,          /* bmAttributes (Bulk).             */
												0x0040,        /* wMaxPacketSize.                  */
												0x00),         /* bInterval.                       */
												/* Endpoint 1 Descriptor.*/
												USB_DESC_ENDPOINT     (USBD2_DATA_REQUEST_EP|0x80,    /* bEndpointAddress.*/
														0x02,          /* bmAttributes (Bulk).             */
														0x0040,        /* wMaxPacketSize.                  */
														0x00)          /* bInterval.                       */
};

/*
 * Configuration Descriptor wrapper.
 */
static const USBDescriptor vcom_configuration_descriptor = {
		sizeof vcom_configuration_descriptor_data,
		vcom_configuration_descriptor_data
};

/*
 * U.S. English language identifier.
 */
static const uint8_t vcom_string0[] = {
		USB_DESC_BYTE(4),                     /* bLength.                         */
		USB_DESC_BYTE(USB_DESCRIPTOR_STRING), /* bDescriptorType.                 */
		USB_DESC_WORD(0x0409)                 /* wLANGID (U.S. English).          */
};

/*
 * Vendor string.
 */
static const uint8_t vcom_string1[] = {
		USB_DESC_BYTE(38),                    /* bLength.                         */
		USB_DESC_BYTE(USB_DESCRIPTOR_STRING), /* bDescriptorType.                 */
		'S', 0, 'T', 0, 'M', 0, 'i', 0, 'c', 0, 'r', 0, 'o', 0, 'e', 0,
		'l', 0, 'e', 0, 'c', 0, 't', 0, 'r', 0, 'o', 0, 'n', 0, 'i', 0,
		'c', 0, 's', 0
};

/*
 * Device Description string.
 */
static const uint8_t vcom_string2[] = {
		USB_DESC_BYTE(56),                    /* bLength.                         */
		USB_DESC_BYTE(USB_DESCRIPTOR_STRING), /* bDescriptorType.                 */
		'C', 0, 'h', 0, 'i', 0, 'b', 0, 'i', 0, 'O', 0, 'S', 0, '/', 0,
		'R', 0, 'T', 0, ' ', 0, 'V', 0, 'i', 0, 'r', 0, 't', 0, 'u', 0,
		'a', 0, 'l', 0, ' ', 0, 'C', 0, 'O', 0, 'M', 0, ' ', 0, 'P', 0,
		'o', 0, 'r', 0, 't', 0
};

/*
 * Serial Number string.
 */
static const uint8_t vcom_string3[] = {
		USB_DESC_BYTE(8),                     /* bLength.                         */
		USB_DESC_BYTE(USB_DESCRIPTOR_STRING), /* bDescriptorType.                 */
		'0' + CH_KERNEL_MAJOR, 0,
		'0' + CH_KERNEL_MINOR, 0,
		'0' + CH_KERNEL_PATCH, 0
};

/*
 * Strings wrappers array.
 */
static const USBDescriptor vcom_strings[] = {
		{sizeof vcom_string0, vcom_string0},
		{sizeof vcom_string1, vcom_string1},
		{sizeof vcom_string2, vcom_string2},
		{sizeof vcom_string3, vcom_string3}
};

/*
 * Handles the GET_DESCRIPTOR callback. All required descriptors must be
 * handled here.
 */
static const USBDescriptor *get_descriptor(USBDriver *usbp,
		uint8_t dtype,
		uint8_t dindex,
		uint16_t lang) {

	(void)usbp;
	(void)lang;
	switch (dtype) {
	case USB_DESCRIPTOR_DEVICE:
		return &vcom_device_descriptor;
	case USB_DESCRIPTOR_CONFIGURATION:
		return &vcom_configuration_descriptor;
	case USB_DESCRIPTOR_STRING:
		if (dindex < 4)
			return &vcom_strings[dindex];
	}
	return NULL;
}

/**
 * @brief   IN EP1 state.
 */
static USBInEndpointState ep1instate;

/**
 * @brief   OUT EP1 state.
 */
static USBOutEndpointState ep1outstate;

/**
 * @brief   EP1 initialization structure (both IN and OUT).
 */
static const USBEndpointConfig ep1config = {
		USB_EP_MODE_TYPE_BULK,
		NULL,
		sduDataTransmitted,
		sduDataReceived,
		0x0040,
		0x0040,
		&ep1instate,
		&ep1outstate,
		2,
		NULL
};

/**
 * @brief   IN EP2 state.
 */
static USBInEndpointState ep2instate;

/**
 * @brief   EP2 initialization structure (IN only).
 */
static const USBEndpointConfig ep2config = {
		USB_EP_MODE_TYPE_INTR,
		NULL,
		sduInterruptTransmitted,
		NULL,
		0x0010,
		0x0000,
		&ep2instate,
		NULL,
		1,
		NULL
};

static volatile int configured_cnt = 0;

/*
 * Handles the USB driver global events.
 */
static void usb_event(USBDriver *usbp, usbevent_t event) {
	switch (event) {
	case USB_EVENT_RESET:
		return;
	case USB_EVENT_ADDRESS:
		return;
	case USB_EVENT_CONFIGURED:
		chSysLockFromISR();

		/* Enables the endpoints specified into the configuration.
       Note, this callback is invoked from an ISR so I-Class functions
       must be used.*/
		usbInitEndpointI(usbp, USBD2_DATA_REQUEST_EP, &ep1config);
		usbInitEndpointI(usbp, USBD2_INTERRUPT_REQUEST_EP, &ep2config);

		/* Resetting the state of the CDC subsystem.*/
		sduConfigureHookI(&SDU1);

		chSysUnlockFromISR();
		configured_cnt++;
		return;
	case USB_EVENT_SUSPEND:
		return;
	case USB_EVENT_WAKEUP:
		return;
	case USB_EVENT_STALLED:
		return;
	}
	return;
}

/*
 * USB driver configuration.
 */
static const USBConfig usbcfg = {
		usb_event,
		get_descriptor,
		sduRequestsHook,
		NULL
};

/*
 * Serial over USB driver configuration.
 */
const SerialUSBConfig serusbcfg = {
		&USBD1,
		USBD2_DATA_REQUEST_EP,
		USBD2_DATA_AVAILABLE_EP,
		USBD2_INTERRUPT_REQUEST_EP
};

void comm_usb_serial_init(void) {
	palSetPadMode(GPIOA, 11,
			PAL_MODE_ALTERNATE(GPIO_AF_OTG_FS) |
			PAL_STM32_OTYPE_PUSHPULL |
			PAL_STM32_OSPEED_MID1);
	palSetPadMode(GPIOA, 12,
			PAL_MODE_ALTERNATE(GPIO_AF_OTG_FS) |
			PAL_STM32_OTYPE_PUSHPULL |
			PAL_STM32_OSPEED_MID1);

	sduObjectInit(&SDU1);
	sduStart(&SDU1, &serusbcfg);

	/*
	 * Activates the USB driver and then the USB bus pull-up on D+.
	 * Note, a delay is inserted in order to not have to disconnect the cable
	 * after a reset.
	 */
	usbDisconnectBus(serusbcfg.usbp);
	chThdSleepMilliseconds(1500);
	usbStart(serusbcfg.usbp, &usbcfg);
	usbConnectBus(serusbcfg.usbp);
}

int comm_usb_serial_is_active(void) {
	return SDU1.config->usbp->state == USB_ACTIVE;
}

// Every time the USB cable is plugged in a configuration is done. Unfortunately
// I haven't found a way to detect when the USB cable gets unplugged.
int comm_usb_serial_configured_cnt(void) {
	return configured_cnt;
}