From 98eb98b118f4274745b41ad99833c3f08938e60c Mon Sep 17 00:00:00 2001
From: asterix <asterix@38d2e660-2303-0410-9eaa-f027e97ec537>
Date: Tue, 27 Jul 2010 15:45:00 +0000
Subject: [PATCH] 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
---
bertos/cpu/cortex-m3/drv/i2c_stm32.c | 84 ++++++++++++----------------
1 file changed, 35 insertions(+), 49 deletions(-)
diff --git a/bertos/cpu/cortex-m3/drv/i2c_stm32.c b/bertos/cpu/cortex-m3/drv/i2c_stm32.c
index b48d2512..9807de11 100644
--- 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;
}
}
--
2.34.1