I/O Expander: Encode and extend I/O expander options to include interrupt configuration.

drivers/ioexpander/pca9555.c

@@ -369,15 +369,21 @@ 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)((intptr_t)val);
   int ret = -EINVAL;
 
-  if (opt == IOEXPANDER_OPTION_INVERT)
+  if ((opt & IOEXPANDER_OPTION_INVVAL) != 0)
     {
+      unsigned int ival = (unsigned int)((uintptr_t)val);
+      int setting;
+
+      /* Set or clear the bit */
+
+      setting = ((ival & IOEXPANDER_OPTION_INVMASK) == IOEXPANDER_OPTION_INVERT);
+
       /* Get exclusive access to the PCA555 */
 
       pca9555_lock(pca);
-      ret = pca9555_setbit(pca, PCA9555_REG_POLINV, pin, ival);
+      ret = pca9555_setbit(pca, PCA9555_REG_POLINV, pin, setting);
       pca9555_unlock(pca);
     }
 

drivers/ioexpander/skeleton.c

@@ -735,6 +735,7 @@ FAR struct ioexpander_dev_s *skel_initialize(void)
   priv = (FAR struct skel_dev_s *)kmm_zalloc(sizeof(struct skel_dev_s));
   if (!priv)
     {
+      gpioerr("ERROR: Failed to allocate driver instance\n");
       return NULL;
     }
 #else

include/nuttx/ioexpander/ioexpander.h

@@ -66,7 +66,18 @@
 
 /* Pin options */
 
-#define IOEXPANDER_OPTION_INVERT 1 /* Set the "active" level for the line */
+#define IOEXPANDER_OPTION_INVMASK   (3  << 0) /* Bits 0-1: Normal vs Inverted */
+#  define IOEXPANDER_OPTION_INVVAL  (1  << 0) /*   x1: Inversion valid */
+#  define IOEXPANDER_OPTION_INVNONE (1  << 0) /*   01: No inversion */
+#  define IOEXPANDER_OPTION_INVERT  (3  << 0) /*   11: Inverted */
+#define IOEXPANDER_OPTION_INTMASK   (15 << 2) /* Bits 2-5: Interrupt settings */
+#  define IOEXPANDER_OPTION_INTVAL  (1  << 2) /*   xxx1 Interrupt valid */
+#  define IOEXPANDER_OPTION_LEVEL   (2  << 2) /*   xx1x Interrupt on level (vs. edge) */
+#  define IOEXPANDER_OPTION_HIGH    (3  << 2) /*   0011 Interrupt on high level */
+#  define IOEXPANDER_OPTION_LOW     (7  << 2) /*   0111 Interrupt on low level */
+#  define IOEXPANDER_OPTION_RISING  (5  << 2) /*   0101 Interrupt rising edge */
+#  define IOEXPANDER_OPTION_FALLING (9  << 2) /*   1001 Interrupt falling edge */
+#  define IOEXPANDER_OPTION_BOTH    (13 << 2) /*   1101 Interrupt both edges */
 
 /* Access macros ************************************************************/
 
@@ -267,6 +278,7 @@ typedef uint16_t ioe_pinset_t;
 typedef uint32_t ioe_pinset_t;
 #else /* if CONFIG_IOEXPANDER_NPINS <= 64 */
 typedef uint64_t ioe_pinset_t;
+#endif
 
 #ifdef CONFIG_IOEXPANDER_INT_ENABLE
 /* This type represents a pin interrupt callback function */

include/nuttx/ioexpander/pca9555.h

@@ -69,12 +69,11 @@ struct pca9555_config_s
   uint8_t address;     /* 7-bit I2C address (only bits 0-6 used) */
   uint32_t frequency;  /* I2C or SPI frequency */
 
+#ifdef CONFIG_IOEXPANDER_INT_ENABLE
   /* If multiple PCA9555 devices are supported, then an IRQ number must
    * be provided for each so that their interrupts can be distinguished.
    */
 
-#ifndef CONFIG_PCA9555_INT_DISABLE
-
 #ifdef CONFIG_PCA9555_MULTIPLE
   int irq;             /* IRQ number received by interrupt handler. */
 #endif