pios_usbhook.c

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/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, see <http://www.gnu.org/licenses/>
 */

#include "pios.h"
#include "pios_usb.h"           /* PIOS_USB_* */
#include "pios_usbhook.h"
#include "pios_usb_defs.h"      /* struct usb_* */
#include "pios_usb_cdc_priv.h"  /* PIOS_USB_CDC_* */
#include "pios_usb_board_data.h" /* PIOS_USB_BOARD_* */


/* STM32 USB Library Definitions */
#include "usb_core.h"           /* USBD_Class_cb_TypeDef */
#include "usbd_core.h"          /* USBD_Init USBD_OK*/
#include "usbd_ioreq.h"         /* USBD_CtlPrepareRx, USBD_CtlSendData */
#include "usbd_req.h"           /* USBD_CtlError */
#include "usb_dcd_int.h"        /* USBD_OTG_ISR_Handler */

/*
 * External API
 */
static struct pios_usbhook_descriptor Device_Descriptor;

void PIOS_USBHOOK_RegisterDevice(const uint8_t * desc, uint16_t length)
{
        Device_Descriptor.descriptor = desc;
        Device_Descriptor.length     = length;
}

static struct pios_usbhook_descriptor String_Descriptor[4];

void PIOS_USBHOOK_RegisterString(enum usb_string_desc string_id, const uint8_t * desc, uint16_t desc_size)
{
        if (string_id < NELEMENTS(String_Descriptor)) {
                String_Descriptor[string_id].descriptor = desc;
                String_Descriptor[string_id].length     = desc_size;
        }
}

static struct pios_usbhook_descriptor Config_Descriptor;

void PIOS_USBHOOK_RegisterConfig(uint8_t config_id, const uint8_t * desc, uint16_t desc_size)
{
        Config_Descriptor.descriptor = desc;
        Config_Descriptor.length     = desc_size;
}

static USB_OTG_CORE_HANDLE pios_usb_otg_core_handle;
static USBD_Class_cb_TypeDef class_callbacks;
static USBD_DEVICE device_callbacks;
static USBD_Usr_cb_TypeDef user_callbacks;

void PIOS_USBHOOK_Activate(void)
{
        USBD_Init(&pios_usb_otg_core_handle,
                USB_OTG_FS_CORE_ID,
                &device_callbacks,
                &class_callbacks,
                &user_callbacks);
}

void PIOS_USBHOOK_Deactivate(void)
{
        DCD_DevDisconnect(&pios_usb_otg_core_handle);
        USBD_DeInit(&pios_usb_otg_core_handle);
        USB_OTG_StopDevice(&pios_usb_otg_core_handle);
}

void OTG_FS_IRQHandler(void)
{
        PIOS_IRQ_Prologue();

        if(!USBD_OTG_ISR_Handler(&pios_usb_otg_core_handle)) {
                /* spurious interrupt, disable IRQ */

        }

        PIOS_IRQ_Epilogue();
}

struct usb_if_entry {
        struct pios_usb_ifops *ifops;
        uintptr_t context;
};
static struct usb_if_entry usb_if_table[3];
void PIOS_USBHOOK_RegisterIfOps(uint8_t ifnum, struct pios_usb_ifops * ifops, uintptr_t context)
{
        PIOS_Assert(ifnum < NELEMENTS(usb_if_table));
        PIOS_Assert(ifops);

        usb_if_table[ifnum].ifops   = ifops;
        usb_if_table[ifnum].context = context;
}

struct usb_ep_entry {
        pios_usbhook_epcb cb;
        uintptr_t context;
        uint16_t max_len;
};
static struct usb_ep_entry usb_epin_table[6];
void PIOS_USBHOOK_RegisterEpInCallback(uint8_t epnum, uint16_t max_len, pios_usbhook_epcb cb, uintptr_t context)
{
        PIOS_Assert(epnum < NELEMENTS(usb_epin_table));
        PIOS_Assert(cb);

        usb_epin_table[epnum].cb      = cb;
        usb_epin_table[epnum].context = context;
        usb_epin_table[epnum].max_len = max_len;

        DCD_EP_Open(&pios_usb_otg_core_handle,
                epnum | 0x80,
                max_len,
                USB_OTG_EP_INT);
        /*
         * FIXME do not hardcode endpoint type
         */
}

extern void PIOS_USBHOOK_DeRegisterEpInCallback(uint8_t epnum)
{
        PIOS_Assert(epnum < NELEMENTS(usb_epin_table));

        usb_epin_table[epnum].cb = NULL;

        DCD_EP_Close(&pios_usb_otg_core_handle, epnum | 0x80);
}

static struct usb_ep_entry usb_epout_table[6];
void PIOS_USBHOOK_RegisterEpOutCallback(uint8_t epnum, uint16_t max_len, pios_usbhook_epcb cb, uintptr_t context)
{
        PIOS_Assert(epnum < NELEMENTS(usb_epout_table));
        PIOS_Assert(cb);

        usb_epout_table[epnum].cb      = cb;
        usb_epout_table[epnum].context = context;
        usb_epout_table[epnum].max_len = max_len;

        DCD_EP_Open(&pios_usb_otg_core_handle,
                epnum,
                max_len,
                USB_OTG_EP_INT);
        /*
         * FIXME do not hardcode endpoint type
         */

        /*
         * Make sure we refuse OUT transactions until we explicitly
         * connect a receive buffer with PIOS_USBHOOK_EndpointRx().
         *
         * Without this, the ST USB code will receive on this endpoint
         * and blindly write the data to a NULL pointer which will
         * have the side effect of placing the internal flash into an
         * errored state.  Address 0x0000_0000 is aliased into internal
         * flash via the "Section 2.4 Boot configuration" BOOT0/1 pins.
         */
        DCD_SetEPStatus(&pios_usb_otg_core_handle,
                        epnum,
                        USB_OTG_EP_RX_NAK);
}

extern void PIOS_USBHOOK_DeRegisterEpOutCallback(uint8_t epnum)
{
        PIOS_Assert(epnum < NELEMENTS(usb_epout_table));

        usb_epout_table[epnum].cb = NULL;

        DCD_EP_Close(&pios_usb_otg_core_handle, epnum);
}

void PIOS_USBHOOK_CtrlTx(const uint8_t *buf, uint16_t len)
{
        USBD_CtlSendData(&pios_usb_otg_core_handle, buf, len);
}

void PIOS_USBHOOK_CtrlRx(uint8_t *buf, uint16_t len)
{
        USBD_CtlPrepareRx(&pios_usb_otg_core_handle, buf, len);
}

void PIOS_USBHOOK_EndpointTx(uint8_t epnum, const uint8_t *buf, uint16_t len)
{
        if (pios_usb_otg_core_handle.dev.device_status == USB_OTG_CONFIGURED) {
                DCD_EP_Tx(&pios_usb_otg_core_handle, epnum, buf, len);
        }
}

void PIOS_USBHOOK_EndpointRx(uint8_t epnum, uint8_t *buf, uint16_t len)
{
        DCD_EP_PrepareRx(&pios_usb_otg_core_handle, epnum, buf, len);
}

/*
 * Device level hooks into STM USB library
 */

static const uint8_t * PIOS_USBHOOK_DEV_GetDeviceDescriptor(uint8_t speed, uint16_t *length)
{
        *length = Device_Descriptor.length;
        return Device_Descriptor.descriptor;
}

static const uint8_t * PIOS_USBHOOK_DEV_GetLangIDStrDescriptor(uint8_t speed, uint16_t *length)
{
        *length = String_Descriptor[USB_STRING_DESC_LANG].length;
        return String_Descriptor[USB_STRING_DESC_LANG].descriptor;
}

static const uint8_t * PIOS_USBHOOK_DEV_GetManufacturerStrDescriptor(uint8_t speed, uint16_t *length)
{
        *length = String_Descriptor[USB_STRING_DESC_VENDOR].length;
        return String_Descriptor[USB_STRING_DESC_VENDOR].descriptor;
}

static const uint8_t * PIOS_USBHOOK_DEV_GetProductStrDescriptor(uint8_t speed, uint16_t *length)
{
        *length = String_Descriptor[USB_STRING_DESC_PRODUCT].length;
        return String_Descriptor[USB_STRING_DESC_PRODUCT].descriptor;
}

static const uint8_t * PIOS_USBHOOK_DEV_GetSerialStrDescriptor(uint8_t speed, uint16_t *length)
{
        *length = String_Descriptor[USB_STRING_DESC_SERIAL].length;
        return String_Descriptor[USB_STRING_DESC_SERIAL].descriptor;
}

static const uint8_t * PIOS_USBHOOK_DEV_GetConfigurationStrDescriptor(uint8_t speed, uint16_t *length)
{
        return NULL;
}

static const uint8_t * PIOS_USBHOOK_DEV_GetInterfaceStrDescriptor(uint8_t speed, uint16_t *length)
{
        return NULL;
}

static USBD_DEVICE device_callbacks = {
        .GetDeviceDescriptor           = PIOS_USBHOOK_DEV_GetDeviceDescriptor,
        .GetLangIDStrDescriptor        = PIOS_USBHOOK_DEV_GetLangIDStrDescriptor,
        .GetManufacturerStrDescriptor  = PIOS_USBHOOK_DEV_GetManufacturerStrDescriptor,
        .GetProductStrDescriptor       = PIOS_USBHOOK_DEV_GetProductStrDescriptor,
        .GetSerialStrDescriptor        = PIOS_USBHOOK_DEV_GetSerialStrDescriptor,
        .GetConfigurationStrDescriptor = PIOS_USBHOOK_DEV_GetConfigurationStrDescriptor,
        .GetInterfaceStrDescriptor     = PIOS_USBHOOK_DEV_GetInterfaceStrDescriptor,
};

static void PIOS_USBHOOK_USR_Init(void)
{
        PIOS_USB_ChangeConnectionState(false);

#if 1
        /* Force a physical disconnect/reconnect */
        DCD_DevDisconnect(&pios_usb_otg_core_handle);
        DCD_DevConnect(&pios_usb_otg_core_handle);
#endif
}

static void PIOS_USBHOOK_USR_DeviceReset(uint8_t speed)
{
        PIOS_USB_ChangeConnectionState(false);
}

static void PIOS_USBHOOK_USR_DeviceConfigured(void)
{
        PIOS_USB_ChangeConnectionState(true);
}

static void PIOS_USBHOOK_USR_DeviceSuspended(void)
{
        /* Unhandled */
}

static void PIOS_USBHOOK_USR_DeviceResumed(void)
{
        /* Unhandled */
}

static void PIOS_USBHOOK_USR_DeviceConnected(void)
{
        /* NOP */
}

static void PIOS_USBHOOK_USR_DeviceDisconnected(void)
{
        PIOS_USB_ChangeConnectionState(false);
}

static USBD_Usr_cb_TypeDef user_callbacks = {
        .Init               = PIOS_USBHOOK_USR_Init,
        .DeviceReset        = PIOS_USBHOOK_USR_DeviceReset,
        .DeviceConfigured   = PIOS_USBHOOK_USR_DeviceConfigured,
        .DeviceSuspended    = PIOS_USBHOOK_USR_DeviceSuspended,
        .DeviceResumed      = PIOS_USBHOOK_USR_DeviceResumed,
        .DeviceConnected    = PIOS_USBHOOK_USR_DeviceConnected,
        .DeviceDisconnected = PIOS_USBHOOK_USR_DeviceDisconnected,
};

static uint8_t PIOS_USBHOOK_CLASS_Init(void *pdev, uint8_t cfgidx)
{
        /* Call all of the registered init callbacks */
        for (uint8_t i = 0; i < NELEMENTS(usb_if_table); i++) {
                struct usb_if_entry * usb_if = &(usb_if_table[i]);
                if (usb_if->ifops && usb_if->ifops->init) {
                        usb_if->ifops->init(usb_if->context);
                }
        }
        return USBD_OK;
}

static uint8_t PIOS_USBHOOK_CLASS_DeInit(void *pdev, uint8_t cfgidx)
{
        /* Call all of the registered deinit callbacks */
        for (uint8_t i = 0; i < NELEMENTS(usb_if_table); i++) {
                struct usb_if_entry * usb_if = &(usb_if_table[i]);
                if (usb_if->ifops && usb_if->ifops->deinit) {
                        usb_if->ifops->deinit(usb_if->context);
                }
        }
        return USBD_OK;
}

static struct usb_setup_request usb_ep0_active_req;
static uint8_t PIOS_USBHOOK_CLASS_Setup(void *pdev, USB_SETUP_REQ *req)
{
        switch (req->bmRequest & (USB_REQ_TYPE_MASK | USB_REQ_RECIPIENT_MASK)) {
        case (USB_REQ_TYPE_STANDARD | USB_REQ_RECIPIENT_INTERFACE):
        case (USB_REQ_TYPE_CLASS    | USB_REQ_RECIPIENT_INTERFACE):
        {
                uint8_t ifnum = LOBYTE(req->wIndex);
                if ((ifnum < NELEMENTS(usb_if_table)) &&
                    (usb_if_table[ifnum].ifops && usb_if_table[ifnum].ifops->setup)) {
                        usb_if_table[ifnum].ifops->setup(usb_if_table[ifnum].context, 
                                                         (struct usb_setup_request *)req);
                        if (!(req->bmRequest & 0x80) && req->wLength > 0) {
                                /* Request is a host-to-device data setup packet, keep track of the request details for the EP0_RxReady call */
                                usb_ep0_active_req.bmRequestType = req->bmRequest;
                                usb_ep0_active_req.bRequest      = req->bRequest;
                                usb_ep0_active_req.wValue        = req->wValue;
                                usb_ep0_active_req.wIndex        = req->wIndex;
                                usb_ep0_active_req.wLength       = req->wLength;
                        }
                } else {
                        /* No Setup handler or Setup handler failed */
                        USBD_CtlError (&pios_usb_otg_core_handle, req);
                }
                break;
        }
        default:
                /* Unhandled Setup */
                USBD_CtlError (&pios_usb_otg_core_handle, req);
                break;
        }

        return USBD_OK;
}

static uint8_t PIOS_USBHOOK_CLASS_EP0_TxSent(void *pdev)
{
        return USBD_OK;
}

static uint8_t PIOS_USBHOOK_CLASS_EP0_RxReady(void *pdev)
{
        uint8_t ifnum = LOBYTE(usb_ep0_active_req.wIndex);

        if ((ifnum < NELEMENTS(usb_if_table)) &&
            (usb_if_table[ifnum].ifops && usb_if_table[ifnum].ifops->ctrl_data_out)) {
                usb_if_table[ifnum].ifops->ctrl_data_out(usb_if_table[ifnum].context, 
                                                        &usb_ep0_active_req);
        }

        return USBD_OK;
}

static uint8_t PIOS_USBHOOK_CLASS_DataIn(void *pdev, uint8_t epnum)
{
        /* Remove the direction bit so we can use this as an index */
        uint8_t epnum_idx = epnum & 0x7F;

        if ((epnum_idx < NELEMENTS(usb_epin_table)) && usb_epin_table[epnum_idx].cb) {
                struct usb_ep_entry *ep = &(usb_epin_table[epnum_idx]);
                if (!ep->cb(ep->context, epnum_idx, ep->max_len)) {
                        /* NOTE: use real endpoint number including direction bit */
                        DCD_SetEPStatus(pdev, epnum, USB_OTG_EP_TX_NAK);
                }
        }

        return USBD_OK;
}

static uint8_t PIOS_USBHOOK_CLASS_DataOut(void *pdev, uint8_t epnum)
{
        /* Remove the direction bit so we can use this as an index */
        uint8_t epnum_idx = epnum & 0x7F;

        if ((epnum_idx < NELEMENTS(usb_epout_table)) && usb_epout_table[epnum_idx].cb) {
                struct usb_ep_entry *ep = &(usb_epout_table[epnum_idx]);
                if (!ep->cb(ep->context, epnum_idx, USBD_GetRxCount(pdev, epnum))) {
                        /* NOTE: use real endpoint number including direction bit */
                        DCD_SetEPStatus(pdev, epnum, USB_OTG_EP_RX_NAK);
                }
        }

        return USBD_OK;
}

static uint8_t PIOS_USBHOOK_CLASS_SOF(void *pdev)
{
        return USBD_OK;
}

static uint8_t PIOS_USBHOOK_CLASS_IsoINIncomplete(void *pdev)
{
        return USBD_OK;
}

static uint8_t PIOS_USBHOOK_CLASS_IsoOUTIncomplete(void *pdev)
{
        return USBD_OK;
}

static const uint8_t * PIOS_USBHOOK_CLASS_GetConfigDescriptor(uint8_t speed, uint16_t *length)
{
        *length = Config_Descriptor.length;
        return Config_Descriptor.descriptor;
}

#ifdef USB_OTG_HS_CORE
static const uint8_t * PIOS_USBHOOK_CLASS_GetOtherConfigDescriptor(uint8_t speed, uint16_t *length)
{
        return PIOS_USBHOOK_CLASS_GetConfigDescriptor(speed, length);
}
#endif  /* USB_OTG_HS_CORE */

#ifdef USB_SUPPORT_USER_STRING_DESC
static const uint8_t * PIOS_USBHOOK_CLASS_GetUsrStrDescriptor(uint8_t speed, uint8_t index, uint16_t *length)
{
        return NULL;
}
#endif  /* USB_SUPPORT_USER_STRING_DESC */

static USBD_Class_cb_TypeDef class_callbacks = {
        .Init                     = PIOS_USBHOOK_CLASS_Init,
        .DeInit                   = PIOS_USBHOOK_CLASS_DeInit,
        .Setup                    = PIOS_USBHOOK_CLASS_Setup,
        .EP0_TxSent               = PIOS_USBHOOK_CLASS_EP0_TxSent,
        .EP0_RxReady              = PIOS_USBHOOK_CLASS_EP0_RxReady,
        .DataIn                   = PIOS_USBHOOK_CLASS_DataIn,
        .DataOut                  = PIOS_USBHOOK_CLASS_DataOut,
        .SOF                      = PIOS_USBHOOK_CLASS_SOF,
        .IsoINIncomplete          = PIOS_USBHOOK_CLASS_IsoINIncomplete,
        .IsoOUTIncomplete         = PIOS_USBHOOK_CLASS_IsoOUTIncomplete,
        .GetConfigDescriptor      = PIOS_USBHOOK_CLASS_GetConfigDescriptor,
#ifdef USB_OTG_HS_CORE
        .GetOtherConfigDescriptor = PIOS_USBHOOK_CLASS_GetOtherConfigDescriptor,
#endif  /* USB_OTG_HS_CORE */
#ifdef USB_SUPPORT_USER_STRING_DESC
        .GetUsrStrDescriptor      = PIOS_USBHOOK_CLASS_GetUsrStrDescriptor,
#endif  /* USB_SUPPORT_USER_STRING_DESC */
};