altos: stm: share i2c_stop code between send and recv

This waits for the stop signal to appear on the bus, necessary before
starting another transaction.

Signed-off-by: Keith Packard <keithp@keithp.com>

diff --git a/src/stm/ao_i2c_stm.c b/src/stm/ao_i2c_stm.c
index e46211cd004e15c2c6c495abb9b2143d32e00ecc..763ae6cd5c0ec0fefa7074912c19bada14134175 100644 (file)
--- a/src/stm/ao_i2c_stm.c
+++ b/src/stm/ao_i2c_stm.c
@@ -191,7 +191,6 @@ ao_i2c_start(uint8_t index, uint16_t addr)
 
        ao_i2c_state[index] = I2C_IDLE;
        ao_i2c_addr[index] = addr;
-       printf ("start sr1: %x\n", stm_i2c->sr1);
        out_cr2("start", stm_i2c, AO_STM_I2C_CR2);
        out_cr1("start", stm_i2c,
                AO_STM_I2C_CR1 | (1 << STM_I2C_CR1_START));
@@ -208,20 +207,17 @@ ao_i2c_start(uint8_t index, uint16_t addr)
 }
 
 static void
-ao_i2c_stop(uint8_t index)
+ao_i2c_wait_stop(uint8_t index)
 {
        struct stm_i2c  *stm_i2c = ao_i2c_stm_info[index].stm_i2c;
-       
-       ao_i2c_state[index] = I2C_IDLE;
-       out_cr2("enable isr", stm_i2c,
-               AO_STM_I2C_CR2 | (1 << STM_I2C_CR2_ITEVTEN) | (1 << STM_I2C_CR2_ITERREN));
-       ev_count = 0;
-       out_cr1("stop", stm_i2c, AO_STM_I2C_CR1 | (1 << STM_I2C_CR1_STOP));
+       int     t;
 
-       /* XXX check to see if there is an interrupt here */
-       while (in_cr1("stop", stm_i2c) & (1 << STM_I2C_CR1_STOP))
+       for (t = 0; t < I2C_TIMEOUT; t++) {
+               if (!(in_cr1("wait stop", stm_i2c) & (1 << STM_I2C_CR1_STOP)))
+                       break;
                ao_yield();
-       printf ("ev_count in stop: %d\n", ev_count);
+       }
+       ao_i2c_state[index] = I2C_IDLE;
 }
 
 uint8_t
@@ -266,8 +262,10 @@ ao_i2c_send(void *block, uint16_t len, uint8_t index, uint8_t stop)
                        break;
        out_cr2("send disable isr", stm_i2c, AO_STM_I2C_CR2);
        sei();
-       if (stop)
-               ao_i2c_stop(index);
+       if (stop) {
+               out_cr1("stop", stm_i2c, AO_STM_I2C_CR1 | (1 << STM_I2C_CR1_STOP));
+               ao_i2c_wait_stop(index);
+       }
        return TRUE;
 }
 
@@ -356,15 +354,8 @@ ao_i2c_recv(void *block, uint16_t len, uint8_t index, uint8_t stop)
                ao_dma_done_transfer(rx_dma_index);
                out_cr1("stop recv > 1", stm_i2c, AO_STM_I2C_CR1 | (1 << STM_I2C_CR1_STOP));
        }
-       if (stop) {
-               for (t = 0; t < I2C_TIMEOUT; t++) {
-                       if (!(in_cr1("recv stop", stm_i2c) & (1 << STM_I2C_CR1_STOP)))
-                               break;
-                       ao_yield();
-               }
-               if (t == I2C_TIMEOUT)
-                       return FALSE;
-       }
+       if (stop)
+               ao_i2c_wait_stop(index);
        return ret;
 }