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PCA9555 I/O expander: Fix an error in addressing noted by Stefan Kolb; convert to use I2C_TRANSFER instead of I2C_WRITEREAD which is not thread safe

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This commit is contained in:
Gregory Nutt 2016-01-26 07:59:36 -06:00
parent 26d40fa80c
commit f74fbecf52
2 changed files with 75 additions and 30 deletions
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1
drivers/ioexpander/Kconfig
View file

@ -15,6 +15,7 @@ if IOEXPANDER_PCA9555
config PCA9555_MULTIPLE
bool "Multiple PCA9555 Devices"
default n
depends on EXPERIMENTAL
---help---
Can be defined to support multiple PCA9555 devices on board.

104
drivers/ioexpander/pca9555.c
View file

@ -1,7 +1,7 @@
/****************************************************************************
* drivers/ioexpander/pca9555.c
*
* Copyright (C) 2015 Gregory Nutt. All rights reserved.
* Copyright (C) 2015, 2016 Gregory Nutt. All rights reserved.
* Author: Sebastien Lorquet <sebastien@lorquet.fr>
*
* References:
@ -64,14 +64,17 @@
# warning I2C support is required (CONFIG_I2C)
#endif
#ifndef CONFIG_I2C_WRITEREAD
# warning Support of the I2C writeread() method is required (CONFIG_I2C_WRITEREAD)
#ifndef CONFIG_I2C_TRANSFER
# warning Support of the I2C transfer() method is required (CONFIG_I2C_TRANSFER)
#endif
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int pca9555_writeread(FAR struct pca9555_dev_s *pca,
FAR const uint8_t *wbuffer, int wbuflen, FAR uint8_t *rbuffer,
int rbuflen);
static int pca9555_direction(FAR struct ioexpander_dev_s *dev, uint8_t pin,
int dir);
static int pca9555_option(FAR struct ioexpander_dev_s *dev, uint8_t pin,
@ -126,6 +129,51 @@ static const struct ioexpander_ops_s g_pca9555_ops =
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: pca9555_writeread
*
* Description:
* Write to then read from the I2C device.
*
****************************************************************************/
static int pca9555_writeread(FAR struct pca9555_dev_s *pca,
FAR const uint8_t *wbuffer, int wbuflen,
FAR uint8_t *rbuffer, int rbuflen)
{
struct i2c_msg_s msg[2];
/* Format two messages: The first is a write */
msg[0].addr = pca->config->address;
msg[0].flags = 0;
msg[0].buffer = (uint8_t *)wbuffer; /* Override const */
msg[0].length = wbuflen;
/* The second is either a read (rbuflen > 0) or a write (rbuflen < 0) with
* no restart.
*/
if (rbuflen > 0)
{
msg[1].flags = I2C_M_READ;
}
else
{
msg[1].flags = I2C_M_NORESTART;
rbuflen = -rbuflen;
}
msg[1].addr = pca->config->address;
msg[1].buffer = rbuffer;
msg[1].length = rbuflen;
/* Then perform the transfer */
I2C_SETFREQUENCY(pca->i2c, pca->config->frequency);
return I2C_TRANSFER(pca->i2c, msg, 2);
}
/****************************************************************************
* Name: pca9555_setbit
*
@ -134,12 +182,12 @@ static const struct ioexpander_ops_s g_pca9555_ops =
*
****************************************************************************/
static int pca9555_setbit(FAR struct i2c_dev_s *i2c, uint8_t addr,
static int pca9555_setbit(FAR struct ioexpander_dev_s *dev, uint8_t addr,
uint8_t pin, int bitval)
{
int ret;
FAR struct pca9555_dev_s *pca = (FAR struct pca9555_dev_s *)dev;
uint8_t buf[2];
buf[0] = addr;
int ret;
if (pin > 15)
{
@ -147,11 +195,13 @@ static int pca9555_setbit(FAR struct i2c_dev_s *i2c, uint8_t addr,
}
else if (pin > 7)
{
addr += 1;
addr++;
pin -= 8;
}
ret = I2C_WRITEREAD(i2c, &addr, 1, &buf[1], 1);
buf[0] = addr;
ret = pca9555_writeread(pca, &buf[0], 1, &buf[1], 1);
if (ret < 0)
{
return ret;
@ -166,7 +216,7 @@ static int pca9555_setbit(FAR struct i2c_dev_s *i2c, uint8_t addr,
buf[1] &= ~(1 << pin);
}
return I2C_WRITE(i2c, buf, 2);
return I2C_WRITE(pca->i2c, buf, 2);
}
/****************************************************************************
@ -177,9 +227,10 @@ static int pca9555_setbit(FAR struct i2c_dev_s *i2c, uint8_t addr,
*
****************************************************************************/
static int pca9555_getbit(FAR struct i2c_dev_s *i2c, uint8_t addr,
static int pca9555_getbit(FAR struct ioexpander_dev_s *dev, uint8_t addr,
uint8_t pin, FAR bool *val)
{
FAR struct pca9555_dev_s *pca = (FAR struct pca9555_dev_s *)dev;
uint8_t buf;
int ret;
@ -193,7 +244,7 @@ static int pca9555_getbit(FAR struct i2c_dev_s *i2c, uint8_t addr,
pin -= 8;
}
ret = I2C_WRITEREAD(i2c, &addr, 1, &buf, 1);
ret = pca9555_writeread(pca, &addr, 1, &buf, 1);
if (ret < 0)
{
return ret;
@ -214,8 +265,7 @@ static int pca9555_getbit(FAR struct i2c_dev_s *i2c, uint8_t addr,
static int pca9555_direction(FAR struct ioexpander_dev_s *dev, uint8_t pin,
int direction)
{
FAR struct pca9555_dev_s *pca = (FAR struct pca9555_dev_s *)dev;
return pca9555_setbit(pca->i2c, PCA9555_REG_CONFIG, pin,
return pca9555_setbit(dev, PCA9555_REG_CONFIG, pin,
(direction == IOEXPANDER_DIRECTION_IN));
}
@ -230,12 +280,11 @@ static int pca9555_direction(FAR struct ioexpander_dev_s *dev, uint8_t pin,
static int pca9555_option(FAR struct ioexpander_dev_s *dev, uint8_t pin,
int opt, FAR void *val)
{
FAR struct pca9555_dev_s *pca = (FAR struct pca9555_dev_s *)dev;
int ival = (int)val;
if (opt == IOEXPANDER_OPTION_INVERT)
{
return pca9555_setbit(pca->i2c, PCA9555_REG_POLINV, pin, ival);
return pca9555_setbit(dev, PCA9555_REG_POLINV, pin, ival);
}
return -EINVAL;
@ -252,8 +301,7 @@ static int pca9555_option(FAR struct ioexpander_dev_s *dev, uint8_t pin,
static int pca9555_writepin(FAR struct ioexpander_dev_s *dev, uint8_t pin,
bool value)
{
FAR struct pca9555_dev_s *pca = (FAR struct pca9555_dev_s *)dev;
return pca9555_setbit(pca->i2c, PCA9555_REG_OUTPUT, pin, value);
return pca9555_setbit(dev, PCA9555_REG_OUTPUT, pin, value);
}
/****************************************************************************
@ -267,8 +315,7 @@ static int pca9555_writepin(FAR struct ioexpander_dev_s *dev, uint8_t pin,
static int pca9555_readpin(FAR struct ioexpander_dev_s *dev, uint8_t pin,
FAR bool *value)
{
FAR struct pca9555_dev_s *pca = (FAR struct pca9555_dev_s *)dev;
return pca9555_getbit(pca->i2c, PCA9555_REG_INPUT, pin, value);
return pca9555_getbit(dev, PCA9555_REG_INPUT, pin, value);
}
/****************************************************************************
@ -282,8 +329,7 @@ static int pca9555_readpin(FAR struct ioexpander_dev_s *dev, uint8_t pin,
static int pca9555_readbuf(FAR struct ioexpander_dev_s *dev, uint8_t pin,
FAR bool *value)
{
FAR struct pca9555_dev_s *pca = (FAR struct pca9555_dev_s *)dev;
return pca9555_getbit(pca->i2c, PCA9555_REG_OUTPUT, pin, value);
return pca9555_getbit(dev, PCA9555_REG_OUTPUT, pin, value);
}
#ifdef CONFIG_IOEXPANDER_MULTIPIN
@ -296,18 +342,18 @@ static int pca9555_readbuf(FAR struct ioexpander_dev_s *dev, uint8_t pin,
*
****************************************************************************/
static int pca9555_getmultibits(FAR struct i2c_dev_s *i2c, uint8_t addr,
static int pca9555_getmultibits(FAR struct ioexpander_dev_s *dev, uint8_t addr,
FAR uint8_t *pins, FAR bool *values,
int count)
{
FAR struct pca9555_dev_s *pca = (FAR struct pca9555_dev_s *)dev;
uint8_t buf[2];
int ret = OK;
int i;
int index;
int pin;
ret = I2C_WRITEREAD(i2c, &addr, 1, buf, 2);
ret = pca9555_writeread(pca, &addr, 1, buf, 2);
if (ret < 0)
{
return ret;
@ -359,7 +405,7 @@ static int pca9555_multiwritepin(FAR struct ioexpander_dev_s *dev,
* attempt to read one port only if all pins were on the same port, but
* this would not save much. */
ret = I2C_WRITEREAD(pca->i2c, &addr, 1, &buf[1], 2);
ret = pca9555_writeread(pca, &addr, 1, &buf[1], 2);
if (ret < 0)
{
return ret;
@ -409,8 +455,7 @@ static int pca9555_multireadpin(FAR struct ioexpander_dev_s *dev,
FAR uint8_t *pins, FAR bool *values,
int count)
{
FAR struct pca9555_dev_s *pca = (FAR struct pca9555_dev_s *)dev;
return pca9555_getmultibits(pca->i2c, PCA9555_REG_INPUT,
return pca9555_getmultibits(dev, PCA9555_REG_INPUT,
pins, values, count);
}
@ -426,8 +471,7 @@ static int pca9555_multireadbuf(FAR struct ioexpander_dev_s *dev,
FAR uint8_t *pins, FAR bool *values,
int count)
{
FAR struct pca9555_dev_s *pca = (FAR struct pca9555_dev_s *)dev;
return pca9555_getmultibits(pca->i2c, PCA9555_REG_OUTPUT,
return pca9555_getmultibits(dev, PCA9555_REG_OUTPUT,
pins, values, count);
}
@ -453,7 +497,7 @@ static void pca9555_irqworker(void *arg)
/* Read inputs */
ret = I2C_WRITEREAD(pca->i2c, &addr, 1, buf, 2);
ret = pca9555_writeread(pca, &addr, 1, buf, 2);
if (ret != OK)
{
return;