FTDI Latency timer Getter/setter

cdcftdi.cpp

@@ -86,8 +86,7 @@ uint8_t FTDI::Init(uint8_t parent, uint8_t port, bool lowspeed) {
         if(rcode) {
                 goto FailGetDevDescr;
         }
-        if(udd->idVendor != FTDI_VID || udd->idProduct != wIdProduct)
+        if(udd->idVendor != FTDI_VID || udd->idProduct != wIdProduct) {
-        {
                 USBTRACE("FTDI Init: Product not supported\r\n");
                 USBTRACE2("Expected VID:", FTDI_VID);
                 USBTRACE2("Found VID:", udd->idVendor);
@@ -108,6 +107,9 @@ uint8_t FTDI::Init(uint8_t parent, uint8_t port, bool lowspeed) {
 
         // Extract Max Packet Size from the device descriptor
         epInfo[0].maxPktSize = udd->bMaxPacketSize0;
+        // Some devices set endpoint lengths to zero, which is incorrect.
+        // we should check them, and if zero, set them to 64.
+        if(epInfo[0].maxPktSize == 0) epInfo[0].maxPktSize = 64;
 
         // Assign new address to the device
         rcode = pUsb->setAddr(0, 0, bAddress);
@@ -175,6 +177,12 @@ uint8_t FTDI::Init(uint8_t parent, uint8_t port, bool lowspeed) {
         if(rcode)
                 goto FailSetConfDescr;
 
+        // default latency is 16ms on-chip, reduce it to 1
+        rcode = SetLatency(1);
+        if(rcode)
+                goto FailOnLatency;
+
+
         rcode = pAsync->OnInit(this);
 
         if(rcode)
@@ -185,6 +193,12 @@ uint8_t FTDI::Init(uint8_t parent, uint8_t port, bool lowspeed) {
         ready = true;
         return 0;
 
+FailOnLatency:
+#ifdef DEBUG_USB_HOST
+        USBTRACE("SetLatency: ");
+        goto Fail;
+#endif
+
 FailGetDevDescr:
 #ifdef DEBUG_USB_HOST
         NotifyFailGetDevDescr();
@@ -241,6 +255,9 @@ void FTDI::EndpointXtract(uint8_t conf, uint8_t iface, uint8_t alt, uint8_t prot
         epInfo[index].maxPktSize = (uint8_t)pep->wMaxPacketSize;
         epInfo[index].bmSndToggle = 0;
         epInfo[index].bmRcvToggle = 0;
+        // Some device vendors set endpoint lengths to zero, which is incorrect.
+        // Check, and if zero, set to 64.
+        if(epInfo[index].maxPktSize == 0) epInfo[index].maxPktSize = 64;
 
         bNumEP++;
 
@@ -313,6 +330,26 @@ uint8_t FTDI::SetBaudRate(uint32_t baud) {
         return rv;
 }
 
+// No docs on if this is 8 or 16 bit, so play it safe, make maximum 255ms
+
+uint8_t FTDI::SetLatency(uint8_t l) {
+        uint8_t rv = pUsb->ctrlReq(bAddress, 0, bmREQ_FTDI_OUT, FTDI_SIO_SET_LATENCY_TIMER, l, 0, 0, 0, 0, NULL, NULL);
+        if(rv && rv != hrNAK) {
+                Release();
+        }
+        return rv;
+}
+
+// No docs on if this is 8 or 16 bit, so play it safe, make maximum 255ms
+
+uint8_t FTDI::GetLatency(uint8_t *l) {
+        uint8_t rv = pUsb->ctrlReq(bAddress, 0, bmREQ_FTDI_OUT, FTDI_SIO_GET_LATENCY_TIMER, 0, 0, 0, 0, 1, (uint8_t *)l, NULL);
+        if(rv && rv != hrNAK) {
+                Release();
+        }
+        return rv;
+}
+
 uint8_t FTDI::SetModemControl(uint16_t signal) {
         uint8_t rv = pUsb->ctrlReq(bAddress, 0, bmREQ_FTDI_OUT, FTDI_SIO_MODEM_CTRL, signal & 0xff, signal >> 8, 0, 0, 0, NULL, NULL);
         if(rv && rv != hrNAK) {

cdcftdi.h

@@ -42,6 +42,8 @@ e-mail   :  support@circuitsathome.com
 #define FTDI_SIO_GET_MODEM_STATUS       5  /* Retrieve current value of modem status register */
 #define FTDI_SIO_SET_EVENT_CHAR         6  /* Set the event character */
 #define FTDI_SIO_SET_ERROR_CHAR         7  /* Set the error character */
+#define FTDI_SIO_SET_LATENCY_TIMER      9  /* Set the latency timer */
+#define FTDI_SIO_GET_LATENCY_TIMER      10 /* Get the latency timer */
 
 #define FTDI_SIO_RESET_SIO              0
 #define FTDI_SIO_RESET_PURGE_RX         1
@@ -121,8 +123,10 @@ public:
         uint8_t SetModemControl(uint16_t control);
         uint8_t SetFlowControl(uint8_t protocol, uint8_t xon = 0x11, uint8_t xoff = 0x13);
         uint8_t SetData(uint16_t databm);
+        uint8_t SetLatency(uint8_t l);
+        uint8_t GetLatency(uint8_t *l);
 
-        // Methods for recieving and sending data
+        // Methods for receiving and sending data
         uint8_t RcvData(uint16_t *bytes_rcvd, uint8_t *dataptr);
         uint8_t SndData(uint16_t nbytes, uint8_t *dataptr);
 
@@ -139,7 +143,7 @@ public:
         void EndpointXtract(uint8_t conf, uint8_t iface, uint8_t alt, uint8_t proto, const USB_ENDPOINT_DESCRIPTOR *ep);
 
         virtual bool VIDPIDOK(uint16_t vid, uint16_t pid) {
-                return (vid == FTDI_VID && pid == wIdProduct);
+                return (vid == FTDI_VID && pid == FTDI_PID);
         }
         virtual bool isReady() {
                 return ready;