Add configurable option to choose at compile time which i2c backend to use.

[bertos.git] / bertos / drv / i2c_bitbang.c

diff --git a/bertos/drv/i2c_bitbang.c b/bertos/drv/i2c_bitbang.c
index 7124389854430433cd2fcc2ef88fa472e2d92943..07dd2c04f32ba888305abc0bd14b022cd4e9e87b 100644 (file)
--- a/bertos/drv/i2c_bitbang.c
+++ b/bertos/drv/i2c_bitbang.c
@@ -37,51 +37,64 @@
  */
 
 #include "i2c.h"
-#include "timer.h"
-#include "hw/hw_i2c_bitbang.h"
+#include "cfg/cfg_i2c.h"
+
+#define LOG_LEVEL  I2C_LOG_LEVEL
+#define LOG_FORMAT I2C_LOG_FORMAT
+
+#include <cfg/log.h>
+#include <cfg/macros.h>
+#include <cfg/module.h>
+
+#include <drv/timer.h>
+#include <cpu/irq.h>
 
-#define I2C_PERIOD DIV_ROUND(500000UL / CONFIG_I2C_FREQ)
+#include "hw/hw_i2c_bitbang.h"
 
-INLINE bool i2c_start(void)
+INLINE bool i2c_bitbang_start(void)
 {
        SDA_HI;
        SCL_HI;
-       timer_udelay(I2C_PERIOD);
-       SDA_LOW;
-       timer_udelay(I2C_PERIOD);
-       return !SDA;
+       I2C_HALFBIT_DELAY();
+       SDA_LO;
+       I2C_HALFBIT_DELAY();
+       ASSERT(!SDA_IN);
+       return !SDA_IN;
 }
 
-INLINE void i2c_stop(void)
+void i2c_bitbang_stop(void)
 {
+       SDA_LO;
        SCL_HI;
-       timer_udelay(I2C_PERIOD);
+       I2C_HALFBIT_DELAY();
        SDA_HI;
 }
 
-bool i2c_put(uint8_t _data)
+bool i2c_bitbang_put(uint8_t _data)
 {
+       /* Add ACK bit */
        uint16_t data = (_data << 1) | 1;
-       for (uint16_t i = 0x100; i >= 0; i >>= 1)
+
+       for (uint16_t i = 0x100; i != 0; i >>= 1)
        {
                SCL_LO;
-               timer_udelay(I2C_PERIOD);
                if (data & i)
                        SDA_HI;
                else
                        SDA_LO;
+               I2C_HALFBIT_DELAY();
+
                SCL_HI;
-               timer_udelay(I2C_PERIOD);
-               ASSERT(SDA == (data & i));
+               I2C_HALFBIT_DELAY();
        }
-       bool ack = !SDA;
-       ASSERT(ack);
+
+       bool ack = !SDA_IN;
        SCL_LO;
-       timer_udelay(I2C_PERIOD);
+       I2C_HALFBIT_DELAY();
        return ack;
 }
 
-bool i2c_start_w(uint8_t id)
+bool i2c_bitbang_start_w(uint8_t id)
 {
        id &= ~I2C_READBIT;
        /*
@@ -91,26 +104,27 @@ bool i2c_start_w(uint8_t id)
         * keep trying until the deveice responds with an ACK.
         */
        ticks_t start = timer_clock();
-       while (i2c_start())
+       while (i2c_bitbang_start())
        {
-               if (i2c_put(id))
+               if (i2c_bitbang_put(id))
                        return true;
-               else if (timer_clock() - start > ms_to_ticks(CONFIG_TWI_START_TIMEOUT))
+               else if (timer_clock() - start > ms_to_ticks(CONFIG_I2C_START_TIMEOUT))
                {
                        LOG_ERR("Timeout on I2C start write\n");
                        break;
                }
+               //LOG_INFO("Rep start\n");
        }
 
        return false;
 }
 
-bool i2c_start_r(uint8_t id)
+bool i2c_bitbang_start_r(uint8_t id)
 {
        id |= I2C_READBIT;
-       if (i2c_start())
+       if (i2c_bitbang_start())
        {
-               if (i2c_put(id))
+               if (i2c_bitbang_put(id))
                        return true;
 
                LOG_ERR("NACK on I2c start read\n");
@@ -119,79 +133,48 @@ bool i2c_start_r(uint8_t id)
        return false;
 }
 
-int i2c_get(bool ack)
+int i2c_bitbang_get(bool ack)
 {
        uint8_t data = 0;
-       for (uint8_t i = 0x80; i >= 0; i >>= 1)
+       for (uint8_t i = 0x80; i != 0; i >>= 1)
        {
                SCL_LO;
-               timer_udelay(I2C_PERIOD);
+               I2C_HALFBIT_DELAY();
                SCL_HI;
-               timer_udelay(I2C_PERIOD);
-               if (SDA)
+               if (SDA_IN)
                        data |= i;
+               else
+                       data &= ~i;
+
+               I2C_HALFBIT_DELAY();
        }
        SCL_LO;
-       timer_udelay(I2C_PERIOD);
 
        if (ack)
                SDA_LO;
        else
                SDA_HI;
 
+       I2C_HALFBIT_DELAY();
        SCL_HI;
+       I2C_HALFBIT_DELAY();
+       SCL_LO;
+       SDA_HI;
        /* avoid sign extension */
        return (int)(uint8_t)data;
 }
 
-/**
- * Send a sequence of bytes in master transmitter mode
- * to the selected slave device through the I2C bus.
- *
- * \return true on success, false on error.
- */
-bool i2c_send(const void *_buf, size_t count)
-{
-       const uint8_t *buf = (const uint8_t *)_buf;
-
-       while (count--)
-       {
-               if (!i2c_put(*buf++))
-                       return false;
-       }
-       return true;
-}
+MOD_DEFINE(i2c);
 
 /**
- * Receive a sequence of one or more bytes from the
- * selected slave device in master receive mode through
- * the I2C bus.
- *
- * Received data is placed in \c buf.
- *
- * \note a NACK is automatically given on the last received
- *         byte.
- *
- * \return true on success, false on error
+ * Initialize i2c module.
  */
-bool i2c_recv(void *_buf, size_t count)
+void i2c_bitbang_init(void)
 {
-       uint8_t *buf = (uint8_t *)_buf;
-
-       while (count--)
-       {
-               /*
-                * The last byte read does not has an ACK
-                * to stop communication.
-                */
-               int c = i2c_get(count);
-
-               if (c == EOF)
-                       return false;
-               else
-                       *buf++ = c;
-       }
-
-       return true;
+       MOD_CHECK(timer);
+       I2C_BITBANG_HW_INIT;
+       SDA_HI;
+       SCL_HI;
+       MOD_INIT(i2c);
 }