drivers/adcxx1c: add error checking from i2c

drivers/adcxx1c/adcxx1c.c

@@ -37,6 +37,7 @@
 int adcxx1c_init(adcxx1c_t *dev, const adcxx1c_params_t *params)
 {
     assert(dev && params);
+    int status;
 
     dev->params = *params;
     dev->cb = NULL;
@@ -45,24 +46,28 @@ int adcxx1c_init(adcxx1c_t *dev, const adcxx1c_params_t *params)
     uint8_t reg = 0;
 
     /* Test communication write and read configuration register */
-    i2c_write_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, CONF_TEST_VALUE, 0);
-    i2c_read_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, &reg, 0);
+    status = i2c_write_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, CONF_TEST_VALUE, 0);
+    status += i2c_read_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, &reg, 0);
 
-    if (reg != CONF_TEST_VALUE) {
+    if (status < 0 || reg != CONF_TEST_VALUE) {
         i2c_release(I2C);
-        DEBUG("[adcxx1c] init - error: unable to communicate with the device (reg=%x)\n", reg);
+        DEBUG("[adcxx1c] init - error: unable to communicate with the device "
+              "(reg=%x)\n", reg);
         return ADCXX1C_NODEV;
     }
 
     reg = dev->params.cycle << 5;
-    i2c_write_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, reg, 0);
+    status = i2c_write_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, reg, 0);
     i2c_release(I2C);
+    if (status < 0) {
+        DEBUG("[adcxx1c] init - error: unable to communicate with the device "
+              "(err=%x)\n", status);
+        return ADCXX1C_NOI2C;
+    }
 
-    adcxx1c_set_alert_parameters(dev, dev->params.low_limit,
-                                 dev->params.high_limit,
-                                 dev->params.hysteresis);
-
-    return ADCXX1C_OK;
+    return adcxx1c_set_alert_parameters(dev, dev->params.low_limit,
+                                        dev->params.high_limit,
+                                        dev->params.hysteresis);
 }
 
 int adcxx1c_read_raw(const adcxx1c_t *dev, int16_t *raw)
@@ -94,13 +99,19 @@ static void _alert_cb(void *arg)
 int adcxx1c_enable_alert(adcxx1c_t *dev, adcxx1c_cb_t cb, void *arg)
 {
     uint8_t reg;
+    int status;
 
     i2c_acquire(I2C);
     i2c_read_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, &reg, 0);
     reg |= (dev->params.alert_pin != GPIO_UNDEF ? ADCXX1C_CONF_ALERT_PIN_EN : 0)
             | ADCXX1C_CONF_ALERT_FLAG_EN;
-    i2c_write_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, reg, 0);
+    status = i2c_write_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, reg, 0);
     i2c_release(I2C);
+    if (status < 0) {
+        DEBUG("[adcxx1c] enable_alert - error: unable to communicate with the "
+              "device (err=%d)\n", status);
+        return ADCXX1C_NOI2C;
+    }
 
     if (dev->params.alert_pin != GPIO_UNDEF) {
         dev->cb = cb;
@@ -116,23 +127,42 @@ int adcxx1c_set_alert_parameters(const adcxx1c_t *dev, int16_t low_limit,
                                  int16_t high_limit, int16_t hysteresis)
 {
     uint8_t buf[2];
+    int status;
 
     i2c_acquire(I2C);
 
     low_limit <<= (12 - dev->params.bits);
     buf[0] = low_limit >> 8;
     buf[1] = low_limit & 0xFF;
-    i2c_write_regs(I2C, ADDR, ADCXX1C_LOW_LIMIT_ADDR, buf, 2, 0);
+    status = i2c_write_regs(I2C, ADDR, ADCXX1C_LOW_LIMIT_ADDR, buf, 2, 0);
+    if (status < 0) {
+        i2c_release(I2C);
+        DEBUG("[adcxx1c] set_alert (low limit) - error: unable to communicate "
+              "with the device (err=%d)\n", status);
+        return ADCXX1C_NOI2C;
+    }
 
     high_limit <<= (12 - dev->params.bits);
     buf[0] = high_limit >> 8;
     buf[1] = high_limit & 0xFF;
-    i2c_write_regs(I2C, ADDR, ADCXX1C_HIGH_LIMIT_ADDR, buf, 2, 0);
+    status = i2c_write_regs(I2C, ADDR, ADCXX1C_HIGH_LIMIT_ADDR, buf, 2, 0);
+    if (status < 0) {
+        i2c_release(I2C);
+        DEBUG("[adcxx1c] set_alert (high limit) - error: unable to communicate "
+              "with the device (err=%d)\n", status);
+        return ADCXX1C_NOI2C;
+    }
 
     hysteresis <<= (12 - dev->params.bits);
     buf[0] = hysteresis >> 8;
     buf[1] = hysteresis & 0xFF;
-    i2c_write_regs(I2C, ADDR, ADCXX1C_HYSTERESIS_ADDR, buf, 2, 0);
+    status = i2c_write_regs(I2C, ADDR, ADCXX1C_HYSTERESIS_ADDR, buf, 2, 0);
+    if (status < 0) {
+        i2c_release(I2C);
+        DEBUG("[adcxx1c] set_alert (hysteresis) - error: unable to communicate "
+              "with the device (err=%d)\n", status);
+        return ADCXX1C_NOI2C;
+    }
 
     i2c_release(I2C);