clean up multi I2C GPIO expander detection

Signed-off-by: Michel-FK <michel.stempin@funkey-project.com>
This commit is contained in:
Michel-FK 2021-03-16 08:28:05 +01:00
parent 44035d48c2
commit 87d400a345

View File

@ -26,12 +26,26 @@
#define DEBUG_PRINTF(...)
#endif
/****************************************************************
* Structures
****************************************************************/
typedef struct {
unsigned int address;
char *name;
} i2c_expander_t;
/****************************************************************
* Static variables
****************************************************************/
static int fd_i2c_expander;
static unsigned int i2c_expander_addr;
static char i2c0_sysfs_filename[] = "/dev/i2c-0";
static i2c_expander_t i2c_chip[] = {
{PCAL9539A_I2C_ADDR, "PCAL9539A"},
{PCAL6416A_I2C_ADDR, "PCAL6416A"},
{0, NULL}
};
/****************************************************************
* Static functions
@ -41,32 +55,25 @@ static char i2c0_sysfs_filename[] = "/dev/i2c-0";
* Public functions
****************************************************************/
bool pcal6416a_init(void) {
int i;
if ((fd_i2c_expander = open(i2c0_sysfs_filename,O_RDWR)) < 0) {
printf("Failed to open the I2C bus %s", i2c0_sysfs_filename);
// ERROR HANDLING; you can check errno to see what went wrong
return false;
}
for (i = 0, i2c_expander_addr = 0; i2c_chip[i].address; i++) {
i2c_expander_addr = 0;
/// Probing PCAL9539A chip
if (ioctl(fd_i2c_expander, I2C_SLAVE_FORCE, PCAL9539A_I2C_ADDR) < 0 ||
pcal6416a_read_mask_interrupts() < 0) {
printf("In %s - Failed to acquire bus access and/or talk to slave PCAL9539A_I2C_ADDR 0x%02X.\n",
__func__, PCAL9539A_I2C_ADDR);
/// Probing PCAL6416A chip
if (ioctl(fd_i2c_expander, I2C_SLAVE_FORCE, PCAL6416A_I2C_ADDR) < 0 ||
/// Probing I2C GPIO expander chip
if (ioctl(fd_i2c_expander, I2C_SLAVE_FORCE, i2c_chip[i]) < 0 ||
pcal6416a_read_mask_interrupts() < 0) {
printf("In %s - Failed to acquire bus access and/or talk to slave PCAL6416A_I2C_ADDR 0x%02X.\n",
__func__, PCAL6416A_I2C_ADDR);
printf("In %s - Failed to acquire bus access and/or talk to slave %s at address 0x%02X.\n",
__func__, i2c_chip[i].name, i2c_chip[i].address);
} else {
DEBUG_PRINTF("Found I2C gpio expander chip: PCAL6416A\n");
i2c_expander_addr = PCAL6416A_I2C_ADDR;
DEBUG_PRINTF("Found I2C gpio expander chip %s at address 0x%02X\n",
i2c_chip[i].name, i2c_chip[i].address);
i2c_expander_addr = i2c_chip[i].address;
}
} else{
DEBUG_PRINTF("Found I2C gpio expander chip: PCAL9539A\n");
i2c_expander_addr = PCAL9539A_I2C_ADDR;
}
/// GPIO expander chip found?