Merge branch 'master' of https://github.com/microsoft/jacdac-tiny

stm32/i2c.c

@@ -10,6 +10,14 @@
 #endif
 
 #ifdef STM32F0
+#if 1
+// 22.4.10 I2C_TIMINGR register configuration examples
+#if I2C_FAST_MODE
+#define I2C_TIMING 0x00310309
+#else
+#define I2C_TIMING 0x00420F13
+#endif
+#else
 // rise 100ns, fall 10ns
 #if I2C_FAST_MODE
 #define I2C_TIMING 0x0010020A
@@ -17,6 +25,7 @@
 #define I2C_TIMING 0x00201D2B
 #endif
 #endif
+#endif
 
 static void setup_pin(uint8_t pin) {
     pin_setup_output_af(pin, I2C_AF);
@@ -53,13 +62,17 @@ int i2c_write_reg_buf(uint8_t addr, uint8_t reg, const void *src, unsigned len)
         return -1;
 
     const uint8_t *p = src - 1;
-    while (!LL_I2C_IsActiveFlag_STOP(I2Cx)) {
+    const uint8_t *end = (const uint8_t *)src + len;
+    while (p < end) {
         if (LL_I2C_IsActiveFlag_TXIS(I2Cx)) {
             LL_I2C_TransmitData8(I2Cx, p == src - 1 ? reg : *p);
             p++;
         }
     }
 
+    while (!LL_I2C_IsActiveFlag_STOP(I2Cx))
+        ;
+
     LL_I2C_ClearFlag_STOP(I2Cx);
 
     return 0;
@@ -70,6 +83,8 @@ int i2c_write_buf(uint8_t addr, const void *src, unsigned len) {
     return i2c_write_reg_buf(addr, *p, p + 1, len - 1);
 }
 
+#define MAXREP 10000
+
 int i2c_read_buf(uint8_t addr, uint8_t reg, void *dst, unsigned len) {
     addr <<= 1;
     LL_I2C_HandleTransfer(I2Cx, addr, LL_I2C_ADDRSLAVE_7BIT, 1, LL_I2C_MODE_SOFTEND,
@@ -86,11 +101,21 @@ int i2c_read_buf(uint8_t addr, uint8_t reg, void *dst, unsigned len) {
     LL_I2C_HandleTransfer(I2Cx, addr, LL_I2C_ADDRSLAVE_7BIT, len, LL_I2C_MODE_AUTOEND,
                           LL_I2C_GENERATE_RESTART_7BIT_READ);
     uint8_t *p = dst;
-    while (!LL_I2C_IsActiveFlag_STOP(I2Cx)) {
-        if (LL_I2C_IsActiveFlag_RXNE(I2Cx)) {
-            *p++ = LL_I2C_ReceiveData8(I2Cx);
-        }
+    uint8_t *end = p + len;
+    while (p < end) {
+        unsigned i;
+        for (i = 0; i < MAXREP; ++i)
+            if (LL_I2C_IsActiveFlag_RXNE(I2Cx))
+                break;
+
+        if (i >= MAXREP)
+            return -1;
+
+        *p++ = LL_I2C_ReceiveData8(I2Cx);
     }
+
+    while (!LL_I2C_IsActiveFlag_STOP(I2Cx))
+        ;
     LL_I2C_ClearFlag_STOP(I2Cx);
 
     return 0;