Add last_abort_reason

Fixes #1049

Author: peterharperuk

src/rp2_common/hardware_i2c/i2c.c

@@ -235,6 +235,7 @@ static int i2c_write_blocking_internal(i2c_inst_t *i2c, uint8_t addr, const uint
 
     // nostop means we are now at the end of a *message* but not the end of a *transfer*
     i2c->restart_on_next = nostop;
+    i2c->last_abort_reason = abort_reason;
     return rval;
 }
 
@@ -315,6 +316,7 @@ static int i2c_read_blocking_internal(i2c_inst_t *i2c, uint8_t addr, uint8_t *ds
     }
 
     i2c->restart_on_next = nostop;
+    i2c->last_abort_reason = abort_reason;
     return rval;
 }
 

src/rp2_common/hardware_i2c/include/hardware/i2c.h

@@ -135,6 +135,7 @@ void i2c_set_slave_mode(i2c_inst_t *i2c, bool slave, uint8_t addr);
 struct i2c_inst {
     i2c_hw_t *hw;
     bool restart_on_next;
+    uint32_t last_abort_reason;
 };
 
 /*! \brief Convert I2C instance to hardware instance number