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

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

@ -154,8 +154,7 @@
enum tiva_intstate_e enum tiva_intstate_e
{ {
INTSTATE_IDLE = 0, /* No I2C activity */ INTSTATE_IDLE = 0, /* No I2C activity */
INTSTATE_ADDRESS, /* Address sent, waiting for completion */ INTSTATE_WAITING, /* Waiting for data transfer to complete */
INTSTATE_XFRWAIT, /* Waiting for data transfer to complete */
INTSTATE_DONE /* Interrupt activity complete */ INTSTATE_DONE /* Interrupt activity complete */
}; };
@ -209,11 +208,11 @@ struct tiva_i2c_config_s
struct tiva_i2c_priv_s struct tiva_i2c_priv_s
{ {
const struct tiva_i2c_config_s *config; /* Port configuration */ const struct tiva_i2c_config_s *config; /* Port configuration */
int refs; /* Reference count */
sem_t exclsem; /* Mutual exclusion semaphore */ sem_t exclsem; /* Mutual exclusion semaphore */
#ifndef CONFIG_I2C_POLLED #ifndef CONFIG_I2C_POLLED
sem_t waitsem; /* Interrupt wait semaphore */ sem_t waitsem; /* Interrupt wait semaphore */
#endif #endif
uint8_t refs; /* Reference count */
volatile uint8_t intstate; /* Interrupt handshake (see enum tiva_intstate_e) */ volatile uint8_t intstate; /* Interrupt handshake (see enum tiva_intstate_e) */
uint8_t msgc; /* Message count */ 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); static void tiva_i2c_tracedump(struct tiva_i2c_priv_s *priv);
#endif /* CONFIG_I2C_TRACE */ #endif /* CONFIG_I2C_TRACE */
static void tiva_i2c_sendaddress(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); 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); static int tiva_i2c_interrupt(struct tiva_i2c_priv_s * priv, uint32_t status);
#ifndef CONFIG_I2C_POLLED #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)) 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; return;
} }
@ -937,7 +936,7 @@ static void tiva_i2c_traceevent(struct tiva_i2c_priv_s *priv,
if (priv->tndx >= (CONFIG_I2C_NTRACE-1)) 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; return;
} }
@ -946,7 +945,7 @@ static void tiva_i2c_traceevent(struct tiva_i2c_priv_s *priv,
tiva_i2c_traceclear(priv); tiva_i2c_traceclear(priv);
trace = &priv->trace[priv->tndx]; trace = &priv->trace[priv->tndx];
trace->status = priv->status; trace->status = priv->tstatus;
trace->count = priv->tcount; trace->count = priv->tcount;
trace->time = clock_systimer(); trace->time = clock_systimer();
} }
@ -977,14 +976,14 @@ static void tiva_i2c_tracedump(struct tiva_i2c_priv_s *priv)
#endif /* CONFIG_I2C_TRACE */ #endif /* CONFIG_I2C_TRACE */
/************************************************************************************ /************************************************************************************
* Name: tiva_i2c_sendaddress * Name: tiva_i2c_startxfr
* *
* Description: * Description:
* Send the START conditions/force Master mode * 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; struct i2c_msg_s *msg;
uint32_t regval; 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); 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); 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 /* Set up the basic command. The STOP bit should be set on the last transfer
* UNLESS this there is a repeated start. * UNLESS this there is a repeated start.
*/ */
cmd = I2CM_CS_RUN; cmd |= I2CM_CS_RUN;
if (priv->msgc < 2 && priv->dcnt < 2) if (priv->msgc < 2 && priv->dcnt < 2)
{ {
/* This is the last byte of the last message... add the STOP bit */ /* 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); 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. */ /* 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); 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); DEBUGASSERT(priv->dcnt > 0);
if (priv->intstate == INTSTATE_XFRWAIT) if (priv->intstate == INTSTATE_WAITING)
{ {
/* Data transfer completed. Are we sending or receiving data? */ /* 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 */ /* Send the next byte */
tiva_i2c_nextxfr(priv); tiva_i2c_nextxfr(priv, 0);
} }
else 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); 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, /* Just continue transferring data. In this case,
* no STOP was sent at the end of the last message * 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 * change
*/ */
tiva_i2c_nextxfr(priv); tiva_i2c_nextxfr(priv, 0);
} }
else else
{ {
@ -1251,7 +1239,7 @@ static int tiva_i2c_interrupt(struct tiva_i2c_priv_s *priv, uint32_t status)
* end of the previous message. * end of the previous message.
*/ */
tiva_i2c_sendaddress(priv); tiva_i2c_startxfr(priv);
} }
} }
else else
@ -1277,11 +1265,11 @@ static int tiva_i2c_interrupt(struct tiva_i2c_priv_s *priv, uint32_t status)
*/ */
sem_post(&priv->waitsem); sem_post(&priv->waitsem);
priv->status = mcs; priv->status = 0;
priv->intstate = INTSTATE_DONE; priv->intstate = INTSTATE_DONE;
} }
#else #else
priv->status = mcs; priv->status = 0;
priv->intstate = INTSTATE_DONE; priv->intstate = INTSTATE_DONE;
#endif #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) static int tiva_i2c_initialize(struct tiva_i2c_priv_s *priv)
{ {
const struct tiva_i2c_config_s *config = priv->config;
uint32_t regval; uint32_t regval;
int ret; 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 */ /* Enable clocking to the I2C peripheral */
#ifdef TIVA_SYSCON_RCGCI2C #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", i2cvdbg("I2C%d: RCGI2C[%08x]=%08x\n",
priv->config->devno, TIVA_SYSCON_RCGCI2C, config->devno, TIVA_SYSCON_RCGCI2C, getreg32(TIVA_SYSCON_RCGCI2C));
(unsigned long)getreg32(TIVA_SYSCON_RCGCI2C));
#else #else
modifyreg32(TIVA_SYSCON_RCGC1, 0, priv->rcgbit); modifyreg32(TIVA_SYSCON_RCGC1, 0, priv->rcgbit);
i2cvdbg("I2C%d: RCGC1[%08x]=%08lx\n", i2cvdbg("I2C%d: RCGC1[%08x]=%08x\n",
priv->config->devno, TIVA_SYSCON_RCGC1, config->devno, TIVA_SYSCON_RCGC1, getreg32(TIVA_SYSCON_RCGC1));
(unsigned long)getreg32(TIVA_SYSCON_RCGC1));
#endif #endif
/* Configure pins */ /* 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) if (ret < 0)
{ {
i2cvdbg("I2C%d: tiva_configgpio(%08x) failed: %d\n",
config->scl_pin, ret);
return ret; return ret;
} }
ret = tiva_configgpio(priv->config->sda_pin); ret = tiva_configgpio(config->sda_pin);
if (ret < 0) 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; return ret;
} }
@ -1516,8 +1510,8 @@ static int tiva_i2c_initialize(struct tiva_i2c_priv_s *priv)
*/ */
#ifndef CONFIG_I2C_POLLED #ifndef CONFIG_I2C_POLLED
irq_attach(priv->config->irq, priv->config->isr); irq_attach(config->irq, config->isr);
up_enable_irq(priv->config->irq); up_enable_irq(config->irq);
#endif #endif
return OK; return OK;
} }
@ -1534,7 +1528,7 @@ static int tiva_i2c_uninitialize(struct tiva_i2c_priv_s *priv)
{ {
uint32_t regval; uint32_t regval;
i2cvdbg("I2C%d:\n", priv->config->devno); i2cvdbg("I2C%d: refs=%d\n", priv->config->devno, priv->refs);
/* Disable I2C */ /* 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 regval;
uint32_t tmp; 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 /* Calculate the clock divider that results in the highest frequency that
* is than or equal to the desired speed. * 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); DEBUGASSERT(inst && inst->priv);
priv = 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 */ /* 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_inst_s *inst = (struct tiva_i2c_inst_s *)dev;
struct tiva_i2c_priv_s *priv = inst->priv; struct tiva_i2c_priv_s *priv = inst->priv;
uint32_t regval;
int errval = 0; int errval = 0;
ASSERT(count); 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(). * 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 /* Wait for an ISR, if there was a timeout, fetch latest status to get
* the BUSY flag. * 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) if (tiva_i2c_sem_waitdone(priv) < 0)
{ {
i2cdbg("ERROR: Timed out\n"); i2cdbg("I2C%d: ERROR: Timed out\n", priv->config->devno);
errval = ETIMEDOUT; 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 if ((priv->status & (I2CM_CS_ERROR | I2CM_CS_ARBLST | I2CM_CS_CLKTO)) != 0)
#else #else
else if ((priv->status & (I2CM_CS_ERROR | I2CM_CS_ARBLST)) != 0) else if ((priv->status & (I2CM_CS_ERROR | I2CM_CS_ARBLST)) != 0)
#endif #endif
{ {
i2cdbg("I2C%d: ERROR: I2C error status: %08x\n",
priv->config->devno, priv->status);
if ((priv->status & I2CM_CS_ARBLST) != 0) if ((priv->status & I2CM_CS_ARBLST) != 0)
{ {
/* Arbitration Lost */ /* Arbitration Lost */
@ -1734,7 +1732,7 @@ static int tiva_i2c_process(struct i2c_dev_s *dev, struct i2c_msg_s *msgs,
errval = ENXIO; errval = ENXIO;
} }
#ifdef I2CM_CS_CLKTO #if 0 /* I2CM_CS_CLKTO */
else if ((priv->status & I2CM_CS_CLKTO) != 0) else if ((priv->status & I2CM_CS_CLKTO) != 0)
{ {
/* Timeout */ /* 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, /* This is not an error, but should not happen. The I2CM_CS_BUSBSY signal
* however, if there are unhealthy devices on the bus that need to be reset. * can hang, however, if there are unhealthy devices on the bus that need
* NOTE: We will only see this busy indication if tiva_i2c_sem_waitdone() * to be reset.
* fails above; Otherwise it is cleared.
*/ */
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 /* I2C Bus is for some reason busy. If I2CM_CS_BUSY then none of the
* other bits are valid. * other bits are valid.
*/ */
i2cdbg("I2C%d: ERROR: I2C still busy: %08x\n",
priv->config->devno, regval);
errval = EBUSY; 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 */ /* Ensure that any ISR happening after we finish can't overwrite any user data */
priv->dcnt = 0; priv->dcnt = 0;
priv->ptr = NULL; priv->ptr = NULL;
tiva_i2c_sem_post(dev); tiva_i2c_sem_post(dev);
@ -1855,9 +1861,9 @@ static int tiva_i2c_writeread(struct i2c_dev_s *dev,
}, },
{ {
.addr = inst->address, .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, .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 i2c_dev_s *up_i2cinitialize(int port)
{ {
struct tiva_i2c_priv_s * priv = NULL; /* Private data of device with multiple instances */ 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_inst_s *inst = NULL; /* Device, single instance */
const struct tiva_i2c_config_s *config; /* Constant configuration */ const struct tiva_i2c_config_s *config; /* Constant configuration */
int irqs; int irqs;
i2cvdbg("I2C%d: port=%d\n", port, port); i2cvdbg("I2C%d: Initialize\n", port);
/* Get I2C private structure */ /* Get I2C private structure */
@ -1954,6 +1960,7 @@ struct i2c_dev_s *up_i2cinitialize(int port)
break; break;
#endif #endif
default: default:
i2cdbg("I2C%d: ERROR: Not supported\n", port);
return NULL; return NULL;
} }
@ -1964,10 +1971,6 @@ struct i2c_dev_s *up_i2cinitialize(int port)
return NULL; return NULL;
} }
/* Make sure that the device structure is inialized */
priv->config = config;
/* Initialize instance */ /* Initialize instance */
inst->ops = &tiva_i2c_ops; inst->ops = &tiva_i2c_ops;
@ -1982,9 +1985,16 @@ struct i2c_dev_s *up_i2cinitialize(int port)
irqs = irqsave(); 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); tiva_i2c_sem_init((struct i2c_dev_s *)inst);
/* Initialize the I2C hardware */
tiva_i2c_initialize(priv); tiva_i2c_initialize(priv);
} }
@ -2003,38 +2013,43 @@ struct i2c_dev_s *up_i2cinitialize(int port)
int up_i2cuninitialize(struct i2c_dev_s *dev) int up_i2cuninitialize(struct i2c_dev_s *dev)
{ {
struct tiva_i2c_inst_s *inst = (struct tiva_i2c_inst_s *)dev; struct tiva_i2c_inst_s *inst = (struct tiva_i2c_inst_s *)dev;
struct tiva_i2c_priv_s *priv ;
int irqs; int irqs;
DEBUGASSERT(inst && inst->priv && inst->priv->config); DEBUGASSERT(inst && inst->priv);
i2cvdbg("I2C%d:\n", inst->priv->config->devno); priv = inst->priv;
DEBUGASSERT(priv->config && priv->refs > 0);
i2cvdbg("I2C%d: Uninitialize\n", priv->config->devno);
/* Decrement reference count and check for underflow */ /* Decrement reference count and check for underflow */
if (inst->priv->refs == 0)
{
return ERROR;
}
irqs = irqsave(); 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); /* Yes.. Disable power and other HW resource (GPIO's) */
kmm_free(dev);
return OK; 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); 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; 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 45 PB0/T2CCP0/U1Rx GPIO, J1 pin 3
46 PB1/T2CCP1/U1Tx GPIO, J1 pin 4 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 48 PB3/I2C0SDA/T3CCP1 GPIO, J4 pin 3
58 PB4/AIN10/CAN0Rx/SSI2CLK/T1CCP0 GPIO, J1 pin 7 58 PB4/AIN10/CAN0Rx/SSI2CLK/T1CCP0 GPIO, J1 pin 7
57 PB5/AIN11/CAN0Tx/SSI2FSS/T1CCP1 GPIO, J1 pin 2 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 The Serial EEPROM was mounted on an external adaptor board and connected
to the LaunchPad thusly: to the LaunchPad thusly:
- VCC -- VCC - VCC J1 pin 1 3.3V
- GND -- GND J3 pin 1 5.0V
- PB2 -- SCL - GND J2 pin 1 GND
- PB3 -- SDA J3 pin 2 GND
- PB2 J2 pin 2 SCL
- PB3 J4 pin 3 SDA
Configuration Settings Configuration Settings
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