sergiotarxz/nuttx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Tiva I2C: Fix how I2C transactions are started and some I2C error reporting

Browse Source
This commit is contained in:
Gregory Nutt 2014-12-11 12:31:42 -06:00
parent a190aeeeba
commit b818691a3a
2 changed files with 119 additions and 102 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

209
arch/arm/src/tiva/tiva_i2c.c
View File

@ -154,8 +154,7 @@
enum tiva_intstate_e
{
INTSTATE_IDLE = 0, /* No I2C activity */
INTSTATE_ADDRESS, /* Address sent, waiting for completion */
INTSTATE_XFRWAIT, /* Waiting for data transfer to complete */
INTSTATE_WAITING, /* Waiting for data transfer to complete */
INTSTATE_DONE /* Interrupt activity complete */
};
@ -209,11 +208,11 @@ struct tiva_i2c_config_s
struct tiva_i2c_priv_s
{
const struct tiva_i2c_config_s *config; /* Port configuration */
int refs; /* Reference count */
sem_t exclsem; /* Mutual exclusion semaphore */
#ifndef CONFIG_I2C_POLLED
sem_t waitsem; /* Interrupt wait semaphore */
#endif
uint8_t refs; /* Reference count */
volatile uint8_t intstate; /* Interrupt handshake (see enum tiva_intstate_e) */
uint8_t msgc; /* Message count */
@ -293,8 +292,8 @@ static void tiva_i2c_traceevent(struct tiva_i2c_priv_s *priv,
static void tiva_i2c_tracedump(struct tiva_i2c_priv_s *priv);
#endif /* CONFIG_I2C_TRACE */
static void tiva_i2c_sendaddress(struct tiva_i2c_priv_s *priv);
static void tiva_i2c_nextxfr(struct tiva_i2c_priv_s *priv);
static void tiva_i2c_startxfr(struct tiva_i2c_priv_s *priv);
static void tiva_i2c_nextxfr(struct tiva_i2c_priv_s *priv, uint32_t cmd);
static int tiva_i2c_interrupt(struct tiva_i2c_priv_s * priv, uint32_t status);
#ifndef CONFIG_I2C_POLLED
@ -888,7 +887,7 @@ static void tiva_i2c_tracenew(struct tiva_i2c_priv_s *priv, uint32_t status)
if (priv->tndx >= (CONFIG_I2C_NTRACE-1))
{
i2cdbg("ERROR: Trace table overflow\n");
i2cdbg("I2C%d: ERROR: Trace table overflow\n", priv->config->devno);
return;
}
@ -937,7 +936,7 @@ static void tiva_i2c_traceevent(struct tiva_i2c_priv_s *priv,
if (priv->tndx >= (CONFIG_I2C_NTRACE-1))
{
i2cdbg("ERROR: Trace table overflow\n");
i2cdbg("I2C%d: ERROR: Trace table overflow\n", priv->config->devno);
return;
}
@ -946,7 +945,7 @@ static void tiva_i2c_traceevent(struct tiva_i2c_priv_s *priv,
tiva_i2c_traceclear(priv);
trace = &priv->trace[priv->tndx];
trace->status = priv->status;
trace->status = priv->tstatus;
trace->count = priv->tcount;
trace->time = clock_systimer();
}
@ -977,14 +976,14 @@ static void tiva_i2c_tracedump(struct tiva_i2c_priv_s *priv)
#endif /* CONFIG_I2C_TRACE */
/************************************************************************************
* Name: tiva_i2c_sendaddress
* Name: tiva_i2c_startxfr
*
* Description:
* Send the START conditions/force Master mode
*
************************************************************************************/
static void tiva_i2c_sendaddress(struct tiva_i2c_priv_s *priv)
static void tiva_i2c_startxfr(struct tiva_i2c_priv_s *priv)
{
struct i2c_msg_s *msg;
uint32_t regval;
@ -1007,24 +1006,11 @@ static void tiva_i2c_sendaddress(struct tiva_i2c_priv_s *priv)
}
tiva_i2c_putreg(priv, TIVA_I2CM_SA_OFFSET, regval);
/* Write the command to the control register */
regval = I2CM_CS_RUN;
if ((msg->flags & I2C_M_NORESTART) == 0)
{
regval |= I2CM_CS_START;
}
if (priv->dcnt < 1)
{
regval |= I2CM_CS_STOP;
}
tiva_i2c_putreg(priv, TIVA_I2CM_CS_OFFSET, regval);
tiva_i2c_traceevent(priv, I2CEVENT_SENDADDRESS, msg->addr);
priv->intstate = INTSTATE_ADDRESS;
/* Then initiate the transfer */
tiva_i2c_nextxfr(priv, I2CM_CS_START);
}
/************************************************************************************
@ -1035,15 +1021,13 @@ static void tiva_i2c_sendaddress(struct tiva_i2c_priv_s *priv)
*
************************************************************************************/
static void tiva_i2c_nextxfr(struct tiva_i2c_priv_s *priv)
static void tiva_i2c_nextxfr(struct tiva_i2c_priv_s *priv, uint32_t cmd)
{
uint32_t cmd;
/* Set up the basic command. The STOP bit should be set on the last transfer
* UNLESS this there is a repeated start.
*/
cmd = I2CM_CS_RUN;
cmd |= I2CM_CS_RUN;
if (priv->msgc < 2 && priv->dcnt < 2)
{
/* This is the last byte of the last message... add the STOP bit */
@ -1081,7 +1065,7 @@ static void tiva_i2c_nextxfr(struct tiva_i2c_priv_s *priv)
tiva_i2c_traceevent(priv, I2CEVENT_SENDBYTE, priv->dcnt);
}
priv->intstate = INTSTATE_XFRWAIT;
priv->intstate = INTSTATE_WAITING;
}
/************************************************************************************
@ -1136,7 +1120,11 @@ static int tiva_i2c_interrupt(struct tiva_i2c_priv_s *priv, uint32_t status)
/* Check for errors, in which case, stop the transfer and return. */
else if ((mcs & I2CM_CS_ERROR) != 0)
#if 0 /* I2CM_CS_CLKTO */
else if ((mcs & (I2CM_CS_ERROR | I2CM_CS_ARBLST | I2CM_CS_CLKTO)) != 0)
#else
else if ((mcs & (I2CM_CS_ERROR | I2CM_CS_ARBLST)) != 0)
#endif
{
tiva_i2c_traceevent(priv, I2CEVENT_ERROR, mcs);
@ -1189,7 +1177,7 @@ static int tiva_i2c_interrupt(struct tiva_i2c_priv_s *priv, uint32_t status)
DEBUGASSERT(priv->dcnt > 0);
if (priv->intstate == INTSTATE_XFRWAIT)
if (priv->intstate == INTSTATE_WAITING)
{
/* Data transfer completed. Are we sending or receiving data? */
@ -1213,7 +1201,7 @@ static int tiva_i2c_interrupt(struct tiva_i2c_priv_s *priv, uint32_t status)
{
/* Send the next byte */
tiva_i2c_nextxfr(priv);
tiva_i2c_nextxfr(priv, 0);
}
else
{
@ -1232,7 +1220,7 @@ static int tiva_i2c_interrupt(struct tiva_i2c_priv_s *priv, uint32_t status)
*/
tiva_i2c_traceevent(priv, I2CEVENT_NEXTMSG, priv->msgc);
if (priv->msgv->flags & I2C_M_NORESTART)
if ((priv->msgv->flags & I2C_M_NORESTART) != 0)
{
/* Just continue transferring data. In this case,
* no STOP was sent at the end of the last message
@ -1243,7 +1231,7 @@ static int tiva_i2c_interrupt(struct tiva_i2c_priv_s *priv, uint32_t status)
* change
*/
tiva_i2c_nextxfr(priv);
tiva_i2c_nextxfr(priv, 0);
}
else
{
@ -1251,7 +1239,7 @@ static int tiva_i2c_interrupt(struct tiva_i2c_priv_s *priv, uint32_t status)
* end of the previous message.
*/
tiva_i2c_sendaddress(priv);
tiva_i2c_startxfr(priv);
}
}
else
@ -1277,11 +1265,11 @@ static int tiva_i2c_interrupt(struct tiva_i2c_priv_s *priv, uint32_t status)
*/
sem_post(&priv->waitsem);
priv->status = mcs;
priv->status = 0;
priv->intstate = INTSTATE_DONE;
}
#else
priv->status = mcs;
priv->status = 0;
priv->intstate = INTSTATE_DONE;
#endif
}
@ -1465,39 +1453,45 @@ static int tiva_i2c5_interrupt(int irq, void *context)
static int tiva_i2c_initialize(struct tiva_i2c_priv_s *priv)
{
const struct tiva_i2c_config_s *config = priv->config;
uint32_t regval;
int ret;
i2cvdbg("I2C%d:\n", priv->config->devno);
i2cvdbg("I2C%d: refs=%d\n", config->devno, priv->refs);
/* Enable clocking to the I2C peripheral */
#ifdef TIVA_SYSCON_RCGCI2C
modifyreg32(TIVA_SYSCON_RCGCI2C, 0, SYSCON_RCGCI2C(priv->config->devno));
modifyreg32(TIVA_SYSCON_RCGCI2C, 0, SYSCON_RCGCI2C(config->devno));
i2cvdbg("I2C%d: RCGI2C[%08x]=%08lx\n",
priv->config->devno, TIVA_SYSCON_RCGCI2C,
(unsigned long)getreg32(TIVA_SYSCON_RCGCI2C));
i2cvdbg("I2C%d: RCGI2C[%08x]=%08x\n",
config->devno, TIVA_SYSCON_RCGCI2C, getreg32(TIVA_SYSCON_RCGCI2C));
#else
modifyreg32(TIVA_SYSCON_RCGC1, 0, priv->rcgbit);
i2cvdbg("I2C%d: RCGC1[%08x]=%08lx\n",
priv->config->devno, TIVA_SYSCON_RCGC1,
(unsigned long)getreg32(TIVA_SYSCON_RCGC1));
i2cvdbg("I2C%d: RCGC1[%08x]=%08x\n",
config->devno, TIVA_SYSCON_RCGC1, getreg32(TIVA_SYSCON_RCGC1));
#endif
/* Configure pins */
ret = tiva_configgpio(priv->config->scl_pin);
i2cvdbg("I2C%d: SCL=%08x SDA=%08x\n",
config->devno, config->scl_pin, config->sda_pin);
ret = tiva_configgpio(config->scl_pin);
if (ret < 0)
{
i2cvdbg("I2C%d: tiva_configgpio(%08x) failed: %d\n",
config->scl_pin, ret);
return ret;
}
ret = tiva_configgpio(priv->config->sda_pin);
ret = tiva_configgpio(config->sda_pin);
if (ret < 0)
{
tiva_configgpio(MKI2C_INPUT(priv->config->scl_pin));
i2cvdbg("I2C%d: tiva_configgpio(%08x) failed: %d\n",
config->sda_pin, ret);
tiva_configgpio(MKI2C_INPUT(config->scl_pin));
return ret;
}
@ -1516,8 +1510,8 @@ static int tiva_i2c_initialize(struct tiva_i2c_priv_s *priv)
*/
#ifndef CONFIG_I2C_POLLED
irq_attach(priv->config->irq, priv->config->isr);
up_enable_irq(priv->config->irq);
irq_attach(config->irq, config->isr);
up_enable_irq(config->irq);
#endif
return OK;
}
@ -1534,7 +1528,7 @@ static int tiva_i2c_uninitialize(struct tiva_i2c_priv_s *priv)
{
uint32_t regval;
i2cvdbg("I2C%d:\n", priv->config->devno);
i2cvdbg("I2C%d: refs=%d\n", priv->config->devno, priv->refs);
/* Disable I2C */
@ -1578,7 +1572,7 @@ static uint32_t tiva_i2c_setclock(struct tiva_i2c_priv_s *priv, uint32_t frequen
uint32_t regval;
uint32_t tmp;
i2cvdbg("I2C%d: frequency: %lu\n", priv->config->devno, (unsigned long)frequency);
i2cvdbg("I2C%d: frequency: %u\n", priv->config->devno, frequency);
/* Calculate the clock divider that results in the highest frequency that
* is than or equal to the desired speed.
@ -1623,7 +1617,7 @@ static uint32_t tiva_i2c_setfrequency(struct i2c_dev_s *dev, uint32_t frequency)
DEBUGASSERT(inst && inst->priv);
priv = inst->priv;
i2cvdbg("I2C%d: frequency: %lu\n", inst->priv->config->devno, (unsigned long)frequency);
i2cvdbg("I2C%d: frequency: %u\n", inst->priv->config->devno, frequency);
/* Get exclusive access to the I2C device */
@ -1674,6 +1668,7 @@ static int tiva_i2c_process(struct i2c_dev_s *dev, struct i2c_msg_s *msgs,
{
struct tiva_i2c_inst_s *inst = (struct tiva_i2c_inst_s *)dev;
struct tiva_i2c_priv_s *priv = inst->priv;
uint32_t regval;
int errval = 0;
ASSERT(count);
@ -1705,7 +1700,7 @@ static int tiva_i2c_process(struct i2c_dev_s *dev, struct i2c_msg_s *msgs,
* interrupts will be enabled within tiva_i2c_waitdone().
*/
tiva_i2c_sendaddress(priv);
tiva_i2c_startxfr(priv);
/* Wait for an ISR, if there was a timeout, fetch latest status to get
* the BUSY flag.
@ -1713,15 +1708,18 @@ static int tiva_i2c_process(struct i2c_dev_s *dev, struct i2c_msg_s *msgs,
if (tiva_i2c_sem_waitdone(priv) < 0)
{
i2cdbg("ERROR: Timed out\n");
i2cdbg("I2C%d: ERROR: Timed out\n", priv->config->devno);
errval = ETIMEDOUT;
}
#ifdef I2CM_CS_CLKTO
#if 0 /* I2CM_CS_CLKTO */
else if ((priv->status & (I2CM_CS_ERROR | I2CM_CS_ARBLST | I2CM_CS_CLKTO)) != 0)
#else
else if ((priv->status & (I2CM_CS_ERROR | I2CM_CS_ARBLST)) != 0)
#endif
{
i2cdbg("I2C%d: ERROR: I2C error status: %08x\n",
priv->config->devno, priv->status);
if ((priv->status & I2CM_CS_ARBLST) != 0)
{
/* Arbitration Lost */
@ -1734,7 +1732,7 @@ static int tiva_i2c_process(struct i2c_dev_s *dev, struct i2c_msg_s *msgs,
errval = ENXIO;
}
#ifdef I2CM_CS_CLKTO
#if 0 /* I2CM_CS_CLKTO */
else if ((priv->status & I2CM_CS_CLKTO) != 0)
{
/* Timeout */
@ -1750,18 +1748,26 @@ static int tiva_i2c_process(struct i2c_dev_s *dev, struct i2c_msg_s *msgs,
}
}
/* This is not an error, but should not happen. The BUSY signal can hang,
* however, if there are unhealthy devices on the bus that need to be reset.
* NOTE: We will only see this busy indication if tiva_i2c_sem_waitdone()
* fails above; Otherwise it is cleared.
/* This is not an error, but should not happen. The I2CM_CS_BUSBSY signal
* can hang, however, if there are unhealthy devices on the bus that need
* to be reset.
*/
if ((tiva_i2c_getreg(priv, TIVA_I2CM_CS_OFFSET) & (I2CM_CS_BUSY | I2CM_CS_BUSBSY)) != 0)
regval = tiva_i2c_getreg(priv, TIVA_I2CM_CS_OFFSET);
/* The status bits are not valid if BUSY is set. We will just have to
* assume that everything went OK.
*/
if ((regval & I2CM_CS_BUSY) != 0 && (regval & I2CM_CS_BUSBSY) != 0)
{
/* I2C Bus is for some reason busy. If I2CM_CS_BUSY then none of the
* other bits are valid.
*/
i2cdbg("I2C%d: ERROR: I2C still busy: %08x\n",
priv->config->devno, regval);
errval = EBUSY;
}
@ -1772,7 +1778,7 @@ static int tiva_i2c_process(struct i2c_dev_s *dev, struct i2c_msg_s *msgs,
/* Ensure that any ISR happening after we finish can't overwrite any user data */
priv->dcnt = 0;
priv->ptr = NULL;
priv->ptr = NULL;
tiva_i2c_sem_post(dev);
@ -1855,9 +1861,9 @@ static int tiva_i2c_writeread(struct i2c_dev_s *dev,
},
{
.addr = inst->address,
.flags = inst->flags | ((buflen>0) ? I2C_M_READ : I2C_M_NORESTART),
.flags = inst->flags | ((buflen > 0) ? I2C_M_READ : I2C_M_NORESTART),
.buffer = buffer,
.length = (buflen>0) ? buflen : -buflen
.length = (buflen > 0) ? buflen : -buflen
}
};
@ -1906,12 +1912,12 @@ static int tiva_i2c_transfer(struct i2c_dev_s *dev, struct i2c_msg_s *msgs,
struct i2c_dev_s *up_i2cinitialize(int port)
{
struct tiva_i2c_priv_s * priv = NULL; /* Private data of device with multiple instances */
struct tiva_i2c_inst_s * inst = NULL; /* Device, single instance */
struct tiva_i2c_priv_s *priv = NULL; /* Private data of device with multiple instances */
struct tiva_i2c_inst_s *inst = NULL; /* Device, single instance */
const struct tiva_i2c_config_s *config; /* Constant configuration */
int irqs;
i2cvdbg("I2C%d: port=%d\n", port, port);
i2cvdbg("I2C%d: Initialize\n", port);
/* Get I2C private structure */
@ -1954,6 +1960,7 @@ struct i2c_dev_s *up_i2cinitialize(int port)
break;
#endif
default:
i2cdbg("I2C%d: ERROR: Not supported\n", port);
return NULL;
}
@ -1964,10 +1971,6 @@ struct i2c_dev_s *up_i2cinitialize(int port)
return NULL;
}
/* Make sure that the device structure is inialized */
priv->config = config;
/* Initialize instance */
inst->ops = &tiva_i2c_ops;
@ -1982,9 +1985,16 @@ struct i2c_dev_s *up_i2cinitialize(int port)
irqs = irqsave();
if ((volatile int)priv->refs++ == 0)
priv->refs++;
if (priv->refs == 1)
{
/* Initialize the device structure */
priv->config = config;
tiva_i2c_sem_init((struct i2c_dev_s *)inst);
/* Initialize the I2C hardware */
tiva_i2c_initialize(priv);
}
@ -2003,38 +2013,43 @@ struct i2c_dev_s *up_i2cinitialize(int port)
int up_i2cuninitialize(struct i2c_dev_s *dev)
{
struct tiva_i2c_inst_s *inst = (struct tiva_i2c_inst_s *)dev;
struct tiva_i2c_priv_s *priv ;
int irqs;
DEBUGASSERT(inst && inst->priv && inst->priv->config);
i2cvdbg("I2C%d:\n", inst->priv->config->devno);
DEBUGASSERT(inst && inst->priv);
priv = inst->priv;
DEBUGASSERT(priv->config && priv->refs > 0);
i2cvdbg("I2C%d: Uninitialize\n", priv->config->devno);
/* Decrement reference count and check for underflow */
if (inst->priv->refs == 0)
{
return ERROR;
}
irqs = irqsave();
if (--inst->priv->refs)
/* Free this instance */
kmm_free(inst);
/* Check if the reference count will decrement to zero */
if (priv->refs < 2)
{
irqrestore(irqs);
kmm_free(dev);
return OK;
/* Yes.. Disable power and other HW resource (GPIO's) */
tiva_i2c_uninitialize(priv);
/* Release unused resources */
tiva_i2c_sem_destroy(dev);
}
else
{
/* No.. just decrement the number of references to the device */
priv->refs--;
}
irqrestore(irqs);
/* Disable power and other HW resource (GPIO's) */
tiva_i2c_uninitialize(inst->priv);
/* Release unused resources */
tiva_i2c_sem_destroy((struct i2c_dev_s *)dev);
kmm_free(dev);
return OK;
}

12
configs/tm4c123g-launchpad/README.txt
View File

@ -40,7 +40,7 @@ PIN SIGNAL(S) LanchPad Function
45 PB0/T2CCP0/U1Rx GPIO, J1 pin 3
46 PB1/T2CCP1/U1Tx GPIO, J1 pin 4
47 PB2/I2C0SCL/T3CCP0 GPIO, J2, pin 3
47 PB2/I2C0SCL/T3CCP0 GPIO, J2 pin 2
48 PB3/I2C0SDA/T3CCP1 GPIO, J4 pin 3
58 PB4/AIN10/CAN0Rx/SSI2CLK/T1CCP0 GPIO, J1 pin 7
57 PB5/AIN11/CAN0Tx/SSI2FSS/T1CCP1 GPIO, J1 pin 2
@ -94,10 +94,12 @@ AT24 Serial EEPROM
The Serial EEPROM was mounted on an external adaptor board and connected
to the LaunchPad thusly:
- VCC -- VCC
- GND -- GND
- PB2 -- SCL
- PB3 -- SDA
- VCC J1 pin 1 3.3V
J3 pin 1 5.0V
- GND J2 pin 1 GND
J3 pin 2 GND
- PB2 J2 pin 2 SCL
- PB3 J4 pin 3 SDA
Configuration Settings
----------------------