C source added for STM32L0/F0 USB device

readme.md

@@ -1,4 +1,4 @@
-### Lightweight USB Device Stack ###
+### Lightweight USB Device Stack ###
 
 + Lightweight and fast
 + Event-driven process workflow
@@ -9,7 +9,8 @@
 
 | MCU series | Driver Name | Written on | Endpoints (1) | Internal S/N | Doublebuffered transfer   |
 | ---------- | ----------- | ---------- | ------------- |------------- | ------------------------- |
-| STM32L0    | usb_stml0a  | GCC ASM    |             8 | FNV1A 32bit  | ISO, BULK OUT, BULK IN (2)|
+| STM32L0/F0 | usb_stml0a  | GCC ASM    |             8 | FNV1A 32bit  | ISO, BULK OUT, BULK IN (2)|
+| STM32L0/F0 | usb_stmv0   | C          |             8 | FNV1A 32bit  | ISO, BULK OUT, BULK IN (2)|
 
 
 1. Single physicsl endpoint can be used to implement

src/usb_32v0.c

@@ -0,0 +1,455 @@
+#include <stdint.h>
+#include "stm32.h"
+#include "usb.h"
+
+
+#ifndef USB_PMASIZE
+    #warning PMA memory size is not defined. Use 1k by default
+    #define USB_PMASIZE 0x400
+#endif
+
+#define USB_EP_SWBUF_TX     USB_EP_DTOG_RX
+#define USB_EP_SWBUF_RX     USB_EP_DTOG_TX
+
+
+#define EP_TOGGLE_SET(epr, bits, mask) *(epr) = (*(epr) ^ (bits)) & (USB_EPREG_MASK | (mask))
+
+#define EP_TX_STALL(epr)    EP_TOGGLE_SET((epr), USB_EP_TX_STALL,                   USB_EPTX_STAT)
+#define EP_RX_STALL(epr)    EP_TOGGLE_SET((epr), USB_EP_RX_STALL,                   USB_EPRX_STAT)
+#define EP_TX_UNSTALL(epr)  EP_TOGGLE_SET((epr), USB_EP_TX_NAK,                     USB_EPTX_STAT | USB_EP_DTOG_TX)
+#define EP_RX_UNSTALL(epr)  EP_TOGGLE_SET((epr), USB_EP_RX_VALID,                   USB_EPRX_STAT | USB_EP_DTOG_RX)
+#define EP_DTX_UNSTALL(epr) EP_TOGGLE_SET((epr), USB_EP_TX_VALID,                   USB_EPTX_STAT | USB_EP_DTOG_TX | USB_EP_SWBUF_TX)
+#define EP_DRX_UNSTALL(epr) EP_TOGGLE_SET((epr), USB_EP_RX_VALID | USB_EP_SWBUF_RX, USB_EPRX_STAT | USB_EP_DTOG_RX | USB_EP_SWBUF_RX)
+#define EP_TX_VALID(epr)    EP_TOGGLE_SET((epr), USB_EP_TX_VALID,                   USB_EPTX_STAT)
+#define EP_RX_VALID(epr)    EP_TOGGLE_SET((epr), USB_EP_RX_VALID,                   USB_EPRX_STAT)
+
+
+
+typedef union pma_table {
+    struct {
+    uint16_t    txadr;
+    uint16_t    txcnt;
+    uint16_t    rxadr;
+    uint16_t    rxcnt;
+    };
+    struct {
+    uint16_t    txadr0;
+    uint16_t    txcnt0;
+    uint16_t    txadr1;
+    uint16_t    txcnt1;
+    };
+    struct {
+    uint16_t    rxadr0;
+    uint16_t    rxcnt0;
+    uint16_t    rxadr1;
+    uint16_t    rxcnt1;
+    };
+} pma_table;
+
+
+/** \brief Helper function. Returns pointer to the buffer descriptor table.
+ */
+inline static pma_table *EPT(uint8_t ep) {
+    return (pma_table*)((ep & 0x07) * 8 + USB_PMAADDR);
+
+}
+
+/** \brief Helper function. Returns pointer to the endpoint control register.
+ */
+inline static volatile uint16_t *EPR(uint8_t ep) {
+    return (uint16_t*)((ep & 0x07) * 4 + USB_BASE);
+}
+
+
+/** \brief Helper function. Returns next available PMA buffer.
+ *
+ * \param sz uint16_t Requested buffer size.
+ * \return uint16_t Buffer address for PMA table.
+ * \note PMA buffers grown from top to bottom like stack.
+ */
+static uint16_t get_next_pma(uint16_t sz) {
+    unsigned _result = USB_PMASIZE;
+    for (int i = 0; i < 8; i++) {
+        pma_table *tbl = EPT(i);
+        if ((tbl->rxadr) && (tbl->rxadr < _result)) _result = tbl->rxadr;
+        if ((tbl->txadr) && (tbl->txadr < _result)) _result = tbl->txadr;
+    }
+    if ( _result < (8 * sizeof(pma_table) + sz)) {
+        return 0;
+    } else {
+        return _result - sz;
+    }
+}
+
+void ep_setstall(uint8_t ep, bool stall) {
+    volatile uint16_t *reg = EPR(ep);
+    /* ISOCHRONOUS endpoint can't be stalled or unstalled */
+    if (USB_EP_ISOCHRONOUS == (*reg & USB_EP_T_FIELD)) return;
+    /* If it's an IN endpoint */
+    if (ep & 0x80) {
+        /* DISABLED endpoint can't be stalled or unstalled */
+        if (USB_EP_TX_DIS == (*reg & USB_EPTX_STAT)) return;
+        if (stall) {
+            EP_TX_STALL(reg);
+        } else {
+            /* if it's a doublebuffered endpoint */
+            if ((USB_EP_KIND | USB_EP_BULK) == (*reg & (USB_EP_T_FIELD | USB_EP_KIND))) {
+                /* set endpoint to VALID and clear DTOG_TX & SWBUF_TX */
+                EP_DTX_UNSTALL(reg);
+            } else {
+                /* set endpoint to NAKED and clear DTOG_TX */
+                EP_TX_UNSTALL(reg);
+            }
+        }
+    } else {
+        if (USB_EP_RX_DIS == (*reg & USB_EPRX_STAT)) return;
+        if (stall) {
+            EP_RX_STALL(reg);
+        } else {
+            /* if it's a doublebuffered endpoint */
+            if ((USB_EP_KIND | USB_EP_BULK) == (*reg & (USB_EP_T_FIELD | USB_EP_KIND))) {
+                /* set endpoint to VALID, clear DTOG_RX, set SWBUF_RX */
+                EP_DRX_UNSTALL(reg);
+            } else {
+                /* set endpoint to VALID and clear DTOG_RX */
+                EP_RX_UNSTALL(reg);
+            }
+        }
+    }
+}
+
+bool ep_isstalled(uint8_t ep) {
+    if (ep & 0x80) {
+        return (USB_EP_TX_STALL == (USB_EPTX_STAT & *EPR(ep)));
+    } else {
+        return (USB_EP_RX_STALL == (USB_EPRX_STAT & *EPR(ep)));
+    }
+}
+
+void enable(bool enable) {
+    if (enable) {
+        RCC->APB1ENR  |=  RCC_APB1ENR_USBEN;
+        RCC->APB1RSTR |= RCC_APB1RSTR_USBRST;
+        RCC->APB1RSTR &= ~RCC_APB1RSTR_USBRST;
+        USB->CNTR = USB_CNTR_CTRM | USB_CNTR_RESETM | USB_CNTR_SOFM | USB_CNTR_ESOFM | USB_CNTR_ERRM | USB_CNTR_SUSPM | USB_CNTR_WKUPM;
+    } else if (RCC->APB1ENR & RCC_APB1ENR_USBEN) {
+        USB->BCDR = 0;
+        RCC->APB1RSTR |= RCC_APB1RSTR_USBRST;
+        RCC->APB1ENR &= ~RCC_APB1ENR_USBEN;
+    }
+}
+
+void reset (void) {
+    USB->CNTR |= USB_CNTR_FRES;
+    USB->CNTR &= ~USB_CNTR_FRES;
+}
+
+void connect(bool connect) {
+    USB->BCDR = (connect) ? USB_BCDR_DPPU : 0;
+}
+
+void setaddr (uint8_t addr) {
+    USB->DADDR = USB_DADDR_EF | addr;
+}
+
+
+bool ep_config(uint8_t ep, uint8_t eptype, uint16_t epsize) {
+    volatile uint16_t *reg = EPR(ep);
+    pma_table *tbl = EPT(ep);
+    /* epsize should be 16-bit aligned */
+    if (epsize & 0x01) epsize++;
+
+    switch (eptype) {
+    case USB_EPTYPE_CONTROL:
+        *reg = USB_EP_CONTROL | (ep & 0x07);
+        break;
+    case USB_EPTYPE_ISOCHRONUS:
+        *reg = USB_EP_ISOCHRONOUS | (ep & 0x07);
+        break;
+    case USB_EPTYPE_BULK:
+        *reg = USB_EP_BULK | (ep & 0x07);
+        break;
+    case USB_EPTYPE_BULK | USB_EPTYPE_DBLBUF:
+        *reg = USB_EP_BULK | USB_EP_KIND | (ep & 0x07);
+        break;
+    default:
+        *reg = USB_EP_INTERRUPT | (ep & 0x07);
+        break;
+    }
+    /* if it TX or CONTROL endpoint */
+    if ((ep & 0x80) || (eptype == USB_EPTYPE_CONTROL)) {
+        uint16_t _pma;
+        _pma = get_next_pma(epsize);
+        if (_pma == 0) return false;
+        if ((eptype == USB_EPTYPE_ISOCHRONUS) ||
+            (eptype == (USB_EPTYPE_BULK | USB_EPTYPE_DBLBUF))) {
+            tbl->txadr0 = _pma;
+            _pma = get_next_pma(epsize);
+            if (_pma == 0) return false;
+            tbl->txadr1 = _pma;
+            tbl->txcnt0 = 0;
+            tbl->txcnt1 = 0;
+            EP_DTX_UNSTALL(reg);
+        } else {
+            tbl->txadr = _pma;
+            tbl->txcnt = 0;
+            EP_TX_UNSTALL(reg);
+        }
+    }
+    if (!(ep & 0x80)) {
+        uint16_t _rxcnt;
+        uint16_t _pma;
+        if (epsize > 62) {
+            if (epsize & 0x1F) {
+                epsize &= 0x1F;
+            } else {
+                epsize -= 0x20;
+            }
+            _rxcnt = 0x8000 | (epsize << 5);
+            epsize += 0x20;
+        } else {
+            _rxcnt = epsize << 9;
+        }
+        _pma = get_next_pma(epsize);
+        if (_pma == 0) return false;
+        if ((eptype == USB_EPTYPE_ISOCHRONUS) ||
+            (eptype == (USB_EPTYPE_BULK | USB_EPTYPE_DBLBUF))) {
+            tbl->rxadr0 = _pma;
+            _pma = get_next_pma(epsize);
+            if (_pma == 0) return false;
+            tbl->rxadr1 = _pma;
+            tbl->rxcnt0 = _rxcnt;
+            tbl->rxcnt1 = _rxcnt;
+            EP_DRX_UNSTALL(reg);
+        } else {
+            tbl->rxadr = _pma;
+            tbl->rxcnt = _rxcnt;
+            EP_RX_UNSTALL(reg);
+        }
+    }
+    return true;
+}
+
+static void ep_deconfig(uint8_t ep) {
+    pma_table *ept = EPT(ep);
+    *EPR(ep) &= ~USB_EPREG_MASK;
+    ept->rxadr = 0;
+    ept->rxcnt = 0;
+    ept->txadr = 0;
+    ept->txcnt = 0;
+}
+
+
+
+static void pma_write(const uint16_t txadr, const uint8_t *buf, uint16_t blen) {
+    uint16_t *pma = (void*)(USB_PMAADDR + txadr);
+    while (blen > 1) {
+        *pma++ = buf[1] << 8 | buf[0];
+        buf += 2;
+        blen -= 2;
+    }
+    if (blen) *pma = *buf;
+}
+
+static void pma_read (const uint16_t rxadr, uint8_t *buf, uint16_t blen, uint16_t rxlen) {
+    uint16_t *pma = (void*)(USB_PMAADDR + rxadr);
+    if (blen > rxlen) blen = rxlen;
+    while (blen) {
+        uint16_t _t = *pma;
+        *buf++ = _t & 0xFF;
+        if (--blen) {
+            *buf++ = _t >> 8;
+            pma++;
+            blen--;
+        } else break;
+    }
+}
+
+uint16_t ep_read(uint8_t ep, void *buf, uint16_t blen) {
+    pma_table *tbl = EPT(ep);
+    volatile uint16_t *reg = EPR(ep);
+    uint16_t rxlen, rxbuf;
+
+    switch (*reg & (USB_EP_T_FIELD | USB_EP_KIND)) {
+    case (USB_EP_BULK | USB_EP_KIND):
+        if (*reg & USB_EP_SWBUF_RX) {
+            rxbuf = tbl->rxadr1;
+            rxlen = tbl->rxcnt1 & 0x03FF;
+        } else {
+            rxbuf = tbl->rxadr0;
+            rxlen = tbl->rxcnt0 & 0x03FF;
+        }
+        pma_read(rxbuf, buf, blen, rxlen);
+        break;
+    case USB_EP_ISOCHRONOUS:
+        if (*reg & USB_EP_DTOG_RX) {
+            rxbuf = tbl->rxadr0;
+            rxlen = tbl->rxcnt0 & 0x03FF;
+        } else {
+            rxbuf = tbl->rxadr1;
+            rxlen = tbl->rxcnt1 & 0x03FF;
+        }
+        pma_read(rxbuf, buf, blen, rxlen);
+        break;
+    default:
+        rxbuf = tbl->rxadr;
+        rxlen = tbl->rxcnt & 0x03FF;
+        pma_read(rxbuf, buf, blen, rxlen);
+        /* setting endpoint to VALID state */
+        EP_RX_VALID(reg);
+        break;
+    }
+    return rxlen;
+}
+
+
+
+uint16_t ep_write(uint8_t ep, void *buf, uint16_t blen) {
+    pma_table *tbl = EPT(ep);
+    volatile uint16_t *reg = EPR(ep);
+    uint16_t txbuf;
+    switch (*reg & (USB_EP_T_FIELD | USB_EP_KIND)) {
+    case (USB_EP_BULK | USB_EP_KIND):
+        if (*reg & USB_EP_SWBUF_TX) {
+            tbl->txcnt1 = blen;
+            txbuf = tbl->txadr1;
+        } else {
+            tbl->txcnt0 = blen;
+            txbuf = tbl->txadr0;
+        }
+        break;
+    case USB_EP_ISOCHRONOUS:
+        if (*reg & USB_EP_DTOG_TX) {
+            tbl->txcnt0 = blen;
+            txbuf = tbl->txadr0;
+        } else {
+            tbl->txcnt1 = blen;
+            txbuf = tbl->txadr1;
+        }
+        break;
+    default:
+        tbl->txcnt = blen;
+        txbuf = tbl->txadr;
+        break;
+    }
+    pma_write(txbuf, buf, blen);
+
+    switch (*reg & (USB_EP_T_FIELD | USB_EP_KIND)) {
+    case (USB_EP_BULK | USB_EP_KIND):
+        /* switching buffer if doublebuffered bulk endpoint */
+        *reg = (*reg & USB_EPREG_MASK) | USB_EP_SWBUF_TX;
+        break;
+    case USB_EP_ISOCHRONOUS:
+        break;
+    default:
+        /* set TX valid to start transfer */
+        EP_TX_VALID(reg);
+    }
+    return blen;
+
+}
+
+uint16_t get_frame (void) {
+    return USB->FNR & USB_FNR_FN;
+}
+
+
+
+void evt_poll(usbd_device *dev, usbd_evt_callback callback) {
+    uint8_t _ev, _ep;
+    uint16_t _istr = USB->ISTR;
+    _ep = _istr & USB_ISTR_EP_ID;
+
+    if (_istr & USB_ISTR_CTR) {
+        volatile uint16_t *reg = EPR(_ep);
+        if (*reg & USB_EP_CTR_TX) {
+            *reg &= (USB_EPREG_MASK ^ USB_EP_CTR_TX);
+            _ep |= 0x80;
+            _ev = usbd_evt_eptx;
+        } else {
+            /* clearing CTR */
+            if ((*reg & (USB_EP_T_FIELD | USB_EP_KIND)) == (USB_EP_BULK | USB_EP_KIND)) {
+                /* switching RX buffer and if doublebuffered bulk endpoint */
+                *reg = (*reg & (USB_EPREG_MASK ^ USB_EP_CTR_RX)) | USB_EP_SWBUF_RX;
+            } else {
+                *reg &= (USB_EPREG_MASK ^ USB_EP_CTR_RX);
+            }
+            _ev = (*reg & USB_EP_SETUP) ? usbd_evt_epsetup : usbd_evt_eprx;
+        }
+    } else if (_istr & USB_ISTR_RESET) {
+        USB->ISTR &= ~USB_ISTR_RESET;
+        USB->BTABLE = 0;
+        for (int i = 0; i < 8; i++) {
+            ep_deconfig(i);
+        }
+        _ev = usbd_evt_reset;
+    } else if (_istr & USB_ISTR_SOF) {
+        _ev = usbd_evt_sof;
+        USB->ISTR &= ~USB_ISTR_SOF;
+    } else if (_istr & USB_ISTR_WKUP) {
+        _ev = usbd_evt_wkup;
+        USB->CNTR &= ~USB_CNTR_FSUSP;
+        USB->ISTR &= ~USB_ISTR_WKUP;
+    } else if (_istr & USB_ISTR_SUSP) {
+        _ev = usbd_evt_susp;
+        USB->CNTR |= USB_CNTR_FSUSP;
+        USB->ISTR &= ~USB_ISTR_SUSP;
+    } else if (_istr & USB_ISTR_ESOF) {
+        USB->ISTR &= ~USB_ISTR_ESOF;
+        _ev = usbd_evt_esof;
+    } else if (_istr & USB_ISTR_ERR) {
+        USB->ISTR &= ~USB_ISTR_ERR;
+        _ev = usbd_evt_error;
+    } else {
+        return;
+    }
+    callback(dev, _ev, _ep);
+}
+
+static uint32_t fnv1a32_turn (uint32_t fnv, uint32_t data ) {
+    for (int i = 0; i < 4 ; i++) {
+        fnv ^= (data & 0xFF);
+        fnv *= 16777619;
+        data >>= 8;
+    }
+    return fnv;
+}
+
+static uint16_t get_serialno_desc(void *buffer) {
+    struct  usb_string_descriptor *dsc = buffer;
+    uint16_t *str = dsc->wString;
+    uint32_t fnv = 2166136261;
+    fnv = fnv1a32_turn(fnv, *(uint32_t*)(UID_BASE + 0x00));
+    fnv = fnv1a32_turn(fnv, *(uint32_t*)(UID_BASE + 0x04));
+    fnv = fnv1a32_turn(fnv, *(uint32_t*)(UID_BASE + 0x14));
+    for (int i = 28; i >= 0; i -= 4 ) {
+        uint16_t c = (fnv >> i) & 0x0F;
+        c += (c < 10) ? '0' : ('A' - 10);
+        *str++ = c;
+    }
+    dsc->bDescriptorType = USB_DTYPE_STRING;
+    dsc->bLength = 18;
+    return 18;
+}
+
+
+
+
+
+const struct usbd_driver usb_stmv0 = {
+    enable,
+    reset,
+    connect,
+    setaddr,
+    ep_config,
+    ep_deconfig,
+    ep_read,
+    ep_write,
+    ep_setstall,
+    ep_isstalled,
+    evt_poll,
+    get_frame,
+    get_serialno_desc,
+};
+
+