Clean up. Use cpu_relax for while loop. Rename check_i2cStatus to wait_event.

git-svn-id: https://src.develer.com/svnoss/bertos/branches/i2c@4081 38d2e660-2303-0410-9eaa-f027e97ec537

diff --git a/bertos/cpu/cortex-m3/drv/i2c_stm32.c b/bertos/cpu/cortex-m3/drv/i2c_stm32.c
index b48d251281b64bd5eee4a6e0804a82a502d496ab..9807de1194fef81a0c39d16eb3d3381994ecdbca 100644 (file)
--- a/bertos/cpu/cortex-m3/drv/i2c_stm32.c
+++ b/bertos/cpu/cortex-m3/drv/i2c_stm32.c
@@ -45,6 +45,7 @@
 #include <cfg/macros.h> // BV()
 #include <cfg/module.h>
 
+#include <cpu/power.h>
 #include <drv/gpio_stm32.h>
 #include <drv/irq_cm3.h>
 #include <drv/clock_stm32.h>
@@ -63,8 +64,17 @@ struct I2cHardware
        bool cached;
 };
 
-#define WAIT_BTF(base)        while( !(base->SR1 & BV(SR1_BTF)) )
-#define WAIT_RXNE(base)        while( !(base->SR1 & BV(SR1_RXNE)) )
+#define WAIT_BTF(base) \
+       do { \
+               while (!(base->SR1 & BV(SR1_BTF))) \
+                       cpu_relax(); \
+       } while (0)
+
+#define WAIT_RXNE(base) \
+       do { \
+               while (!(base->SR1 & BV(SR1_RXNE))) \
+                       cpu_relax(); \
+       } while (0)
 
 INLINE uint32_t get_status(struct stm32_i2c *base)
 {
@@ -72,7 +82,7 @@ INLINE uint32_t get_status(struct stm32_i2c *base)
 }
 
 
-INLINE bool check_i2cStatus(I2c *i2c, uint32_t event)
+INLINE bool wait_event(I2c *i2c, uint32_t event)
 {
        while (true)
        {
@@ -84,39 +94,13 @@ INLINE bool check_i2cStatus(I2c *i2c, uint32_t event)
                if (stat & SR1_ERR_MASK)
                {
                        i2c->hw->base->SR1 &= ~SR1_ERR_MASK;
-                       i2c->hw->base->CR1 |= CR1_START_SET;
                        return false;
                }
-
+               cpu_relax();
        }
-
        return true;
 }
 
-/**
- * Send START condition on the bus.
- *
- * \return true on success, false otherwise.
- */
-INLINE bool i2c_hw_restart(I2c *i2c)
-{
-
-       i2c->hw->base->CR1 |= CR1_ACK_SET | CR1_START_SET;
-
-       if(check_i2cStatus(i2c, I2C_EVENT_MASTER_MODE_SELECT))
-               return true;
-
-       return false;
-}
-
-/**
- * Send STOP condition.
- */
-static void i2c_hw_stop(I2c *i2c)
-{
-       i2c->hw->base->CR1 |= CR1_STOP_SET;
-}
-
 static void i2c_stm32_start(struct I2c *i2c, uint16_t slave_addr)
 {
        i2c->hw->cached = false;
@@ -130,32 +114,41 @@ static void i2c_stm32_start(struct I2c *i2c, uint16_t slave_addr)
                 * keep trying until the eeprom responds with an ACK.
                 */
                ticks_t start = timer_clock();
-               while (i2c_hw_restart(i2c))
+               while (true)
                {
+                       i2c->hw->base->CR1 |= CR1_ACK_SET | CR1_START_SET;
+
+                       if(!wait_event(i2c, I2C_EVENT_MASTER_MODE_SELECT))
+                       {
+                               LOG_ERR("ARBIT lost\n");
+                               i2c->errors |= I2C_ARB_LOST;
+                               break;
+                       }
+
                        i2c->hw->base->DR = slave_addr & OAR1_ADD0_RESET;
 
-                       if(check_i2cStatus(i2c, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED))
+                       if(wait_event(i2c, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED))
                                break;
 
                        if (timer_clock() - start > ms_to_ticks(CONFIG_I2C_START_TIMEOUT))
                        {
                                LOG_ERR("Timeout on I2C START\n");
-                               i2c->errors |= I2C_NO_ACK;
-                               i2c_hw_stop(i2c);
+                               i2c->errors |= I2C_START_TIMEOUT;
+                               i2c->hw->base->CR1 |= CR1_STOP_SET;
                                break;
                        }
                }
 
        }
-       else if (I2C_TEST_START(i2c->flags) == I2C_START_R)
+       else /* (I2C_TEST_START(i2c->flags) == I2C_START_R) */
        {
                i2c->hw->base->CR1 |= CR1_START_SET;
 
-               if(!check_i2cStatus(i2c, I2C_EVENT_MASTER_MODE_SELECT))
+               if(!wait_event(i2c, I2C_EVENT_MASTER_MODE_SELECT))
                {
                        LOG_ERR("ARBIT lost\n");
                        i2c->errors |= I2C_ARB_LOST;
-                       i2c_hw_stop(i2c);
+                       i2c->hw->base->CR1 |= CR1_STOP_SET;
                        return;
                }
 
@@ -164,15 +157,14 @@ static void i2c_stm32_start(struct I2c *i2c, uint16_t slave_addr)
                if (i2c->xfer_size == 2)
                        i2c->hw->base->CR1 |= CR1_ACK_SET | CR1_POS_SET;
 
-               if(!check_i2cStatus(i2c, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED))
+               if(!wait_event(i2c, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED))
                {
                        LOG_ERR("SLAR NACK:%08lx\n", get_status(i2c->hw->base));
                        i2c->errors |= I2C_NO_ACK;
-                       i2c_hw_stop(i2c);
+                       i2c->hw->base->CR1 |= CR1_STOP_SET;
                        return;
                }
 
-
                if (i2c->xfer_size == 1)
                {
                        i2c->hw->base->CR1 &= CR1_ACK_RESET;
@@ -229,11 +221,6 @@ static void i2c_stm32_start(struct I2c *i2c, uint16_t slave_addr)
                        i2c->hw->base->CR1 |= CR1_ACK_SET;
                }
        }
-       else
-       {
-               ASSERT(0);
-       }
-
 }
 
 static void i2c_stm32_put(I2c *i2c, const uint8_t data)
@@ -242,12 +229,11 @@ static void i2c_stm32_put(I2c *i2c, const uint8_t data)
 
        WAIT_BTF(i2c->hw->base);
 
-
        /* Generate the stop if we finish to send all programmed bytes */
-       if ((i2c->xfer_size == 1) &&(I2C_TEST_STOP(i2c->flags) == I2C_STOP))
+       if ((i2c->xfer_size == 1) && (I2C_TEST_STOP(i2c->flags) == I2C_STOP))
        {
-                       check_i2cStatus(i2c, I2C_EVENT_MASTER_BYTE_TRANSMITTED);
-                       i2c_hw_stop(i2c);
+                       wait_event(i2c, I2C_EVENT_MASTER_BYTE_TRANSMITTED);
+                       i2c->hw->base->CR1 |= CR1_STOP_SET;
        }
 }