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I2C. Merge patch from ahaczewski. 

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@4497 35acf78f-673a-0410-8e92-d51de3d6d3f4
master
barthess 2012-08-02 18:30:22 +00:00
parent e737b65a33
commit 660670bb6c
1 changed files with 16 additions and 3 deletions
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19
os/hal/platforms/STM32/I2Cv1/i2c_lld.c
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@ -290,6 +290,9 @@ static void i2c_lld_set_opmode(I2CDriver *i2cp) {
* @details Important but implicit destination of this function is
* clearing interrupts flags.
* @note Internal use only.
* @note Function reads SR2 <b>before</b> SR1. This is workaround, not a bug.
* ADDR was not cleared and it was possible to clear ADDR after
* transfer is properly setup (enabled DMA stream).
*
* @param[in] i2cp pointer to the @p I2CDriver object
*
@ -297,8 +300,8 @@ static void i2c_lld_set_opmode(I2CDriver *i2cp) {
*/
static uint32_t i2c_get_event(I2CDriver *i2cp) {
I2C_TypeDef *dp = i2cp->i2c;
uint16_t regSR1 = dp->SR1;
uint16_t regSR2 = dp->SR2;
uint16_t regSR1 = dp->SR1;
#if CH_DBG_ENABLE_ASSERTS
dbgSR1 = regSR1;
@ -319,15 +322,21 @@ static uint32_t i2c_get_event(I2CDriver *i2cp) {
*/
static void i2c_lld_serve_event_interrupt(I2CDriver *i2cp) {
I2C_TypeDef *dp = i2cp->i2c;
uint32_t event = i2c_get_event(i2cp);
uint32_t rxlen = dmaStreamGetTransactionSize(i2cp->dmarx);
/* Interrupts are disabled just before dmaStreamEnable() because there
is no need of interrupts until next transaction begin. All the work is
done by the DMA.*/
switch (i2c_get_event(i2cp)) {
switch (event) {
case I2C_EV5_MASTER_MODE_SELECT:
dp->DR = i2cp->addr;
break;
case I2C_EV6_MASTER_REC_MODE_SELECTED:
if (rxlen <= 2)
dp->CR1 &= ~I2C_CR1_ACK;
if (rxlen == 2)
dp->CR1 |= I2C_CR1_POS;
dp->CR2 &= ~I2C_CR2_ITEVTEN;
dmaStreamEnable(i2cp->dmarx);
dp->CR2 |= I2C_CR2_LAST; /* Needed in receiver mode. */
@ -338,7 +347,7 @@ static void i2c_lld_serve_event_interrupt(I2CDriver *i2cp) {
break;
case I2C_EV8_2_MASTER_BYTE_TRANSMITTED:
/* Catches BTF event after the end of transmission.*/
if (dmaStreamGetTransactionSize(i2cp->dmarx) > 0) {
if (rxlen > 0) {
/* Starts "read after write" operation, LSB = 1 -> receive.*/
i2cp->addr |= 0x01;
dp->CR1 |= I2C_CR1_START | I2C_CR1_ACK;
@ -351,6 +360,10 @@ static void i2c_lld_serve_event_interrupt(I2CDriver *i2cp) {
default:
break;
}
/* Clear ADDR flag. Last part of workaround
(see comments to i2c_get_event() function). */
if (event & (I2C_SR1_ADDR | I2C_SR1_ADD10))
if (dp->SR2){;}
}
/**