stub of SPI write cmd, multicast cmd

gex.mk

@@ -11,6 +11,7 @@ GEX_SRC_DIR = \
     User/units/digital_out \
     User/units/digital_in \
     User/units/i2c \
+    User/units/spi \
     User/TinyFrame \
     User/CWPack \
     User/tasks

platform/platform.c

@@ -13,6 +13,7 @@
 #include "units/neopixel/unit_neopixel.h"
 #include "units/i2c/unit_i2c.h"
 #include "units/test/unit_test.h"
+#include "units/spi/unit_spi.h"
 
 void plat_init_resources(void)
 {
@@ -77,6 +78,7 @@ void plat_init_resources(void)
     ureg_add_type(&UNIT_DIN);
     ureg_add_type(&UNIT_NEOPIXEL);
     ureg_add_type(&UNIT_I2C);
+    ureg_add_type(&UNIT_SPI);
 
     // Free all present resources
     {

units/spi/unit_spi.c

@@ -417,27 +417,72 @@ static void USPI_deInit(Unit *unit)
 
 // ------------------------------------------------------------------------
 
+
+error_t UU_SPI_Multicast(Unit *unit, uint16_t slaves,
+                     const uint8_t *request,
+                     uint32_t req_len)
+{
+    //
+
+    return E_NOT_IMPLEMENTED;
+}
+
+error_t UU_SPI_Write(Unit *unit, uint8_t slave_num,
+                     const uint8_t *request,
+                     uint8_t *response,
+                     uint32_t req_len,
+                     uint32_t resp_skip,
+                     uint32_t resp_len)
+{
+    //
+
+    return E_NOT_IMPLEMENTED;
+}
+
+
 enum PinCmd_ {
     CMD_WRITE = 0,
+    CMD_MULTICAST = 1,
 };
 
 /** Handle a request message */
 static error_t USPI_handleRequest(Unit *unit, TF_ID frame_id, uint8_t command, PayloadParser *pp)
 {
-    uint16_t addr;
+    uint8_t slave;
-    uint32_t len;
+    uint16_t slaves;
-    uint8_t regnum;
+    uint16_t req_len;
-    uint32_t size;
+    uint16_t resp_skip;
+    uint16_t resp_len;
+    const uint8_t *bb;
 
-    // NOTE: 10-bit addresses must have the highest bit set to 1 for indication (0x8000 | addr)
+    uint32_t len;
 
     switch (command) {
-        /** Write byte(s) - addr:u16, byte(s)  */
+        /** Write and read byte(s) - slave_num:u8, req_len:u16, resp_skip:u16, resp_len:u16, byte(s)  */
         case CMD_WRITE:
-            addr = pp_u16(pp);
+            slave = pp_u8(pp);
-            const uint8_t *bb = pp_tail(pp, &len);
+            req_len = pp_u16(pp);
+            resp_skip = pp_u16(pp);
+            resp_len = pp_u16(pp);
+
+            bb = pp_tail(pp, &len);
+
+            TRY(UU_SPI_Write(unit, slave,
+                             bb, (uint8_t *) unit_tmp512,
+                             req_len, resp_skip, resp_len));
 
-            return UU_SPI_Write(unit, addr, bb, len); // TODo implement function + SPI pins mapping
+            com_respond_buf(frame_id, MSG_SUCCESS, (uint8_t *) unit_tmp512, resp_len);
+            return E_SUCCESS;
+
+        /** Write byte(s) to multiple slaves - slaves:u16, req_len:u16, byte(s)  */
+        case CMD_MULTICAST:
+            slaves = pp_u16(pp);
+            req_len = pp_u16(pp);
+
+            bb = pp_tail(pp, &len);
+
+            TRY(UU_SPI_Multicast(unit, slaves, bb, req_len));
+            return E_SUCCESS;
 
         default:
             return E_UNKNOWN_COMMAND;

units/spi/unit_spi.h

@@ -30,7 +30,7 @@ extern const UnitDriver UNIT_SPI;
  * |<-- resp_len -->|
  *
  * @param unit - SPI unit
- * @param slave_num - slave number (SS pin index)
+ * @param slave_num - slave number (SS pin index, counted from least significant bit)
  * @param request - request bytes buffer
  * @param response - response bytes buffer
  * @param req_len - number of bytes in the request. Will be right-padded with zeros.
@@ -45,4 +45,19 @@ error_t UU_SPI_Write(Unit *unit, uint8_t slave_num,
                      uint32_t resp_skip,
                      uint32_t resp_len);
 
+/**
+ * Write to multiple slaves at once.
+ * This is similar to UU_SPI_Write, but performs no read and works only if the device
+ * is configured as tx-only.
+ *
+ * @param unit - SPI unit
+ * @param slaves - bitmap of slaves to write (packed bits representing the SSN pins)
+ * @param request - request bytes buffer
+ * @param req_len - length of the request buffer
+ * @return success
+ */
+error_t UU_SPI_Multicast(Unit *unit, uint16_t slaves,
+                         const uint8_t *request,
+                         uint32_t req_len);
+
 #endif //GEX_F072_UNIT_SPI_H

utils/error.h

@@ -42,6 +42,7 @@
     X(OVERRUN, NULL) /* used in bulk transfer */ \
     X(PROTOCOL_BREACH, NULL) /* eating with the wrong spoon */  \
     X(BAD_UNIT_TYPE, NULL) \
+    X(NOT_IMPLEMENTED, NULL) \
     \
     /* VFS user errors (those are meant to be shown to user) */ \
     X(ERROR_DURING_TRANSFER, "Error during transfer") \