[PATCH v2 00/10] iio: adc: ad7606: Improvements

@@ -11,6 +11,7 @@ maintainers:
 
 description: |
   Analog Devices AD7606 Simultaneous Sampling ADC
+  https://www.analog.com/media/en/technical-documentation/data-sheets/AD7605-4.pdf
   https://www.analog.com/media/en/technical-documentation/data-sheets/ad7606_7606-6_7606-4.pdf
   https://www.analog.com/media/en/technical-documentation/data-sheets/AD7606B.pdf
   https://www.analog.com/media/en/technical-documentation/data-sheets/AD7616.pdf

@@ -20,9 +20,9 @@ properties:
   compatible:
     enum:
       - adi,ad7605-4
-      - adi,ad7606-8
-      - adi,ad7606-6
       - adi,ad7606-4
+      - adi,ad7606-6
+      - adi,ad7606-8  # Referred to as AD7606 (without -8) in the datasheet
       - adi,ad7606b
       - adi,ad7616
 

@@ -40,60 +40,58 @@ properties:
 
   adi,conversion-start-gpios:
     description:
-      Must be the device tree identifier of the CONVST pin.
-      This logic input is used to initiate conversions on the analog
-      input channels. As the line is active high, it should be marked
-      GPIO_ACTIVE_HIGH.
+      Must be the device tree identifier of the CONVST pin. This logic input is
+      used to initiate conversions on the analog input channels. As the line is
+      active high, it should be marked GPIO_ACTIVE_HIGH.
     maxItems: 1
 
   reset-gpios:
     description:
-      Must be the device tree identifier of the RESET pin. If specified,
-      it will be asserted during driver probe. As the line is active high,
-      it should be marked GPIO_ACTIVE_HIGH.
+      Must be the device tree identifier of the RESET pin. If specified, it will
+      be asserted during driver probe. As the line is active high, it should be
+      marked GPIO_ACTIVE_HIGH.
     maxItems: 1
 
   standby-gpios:
     description:
-      Must be the device tree identifier of the STBY pin. This pin is used
-      to place the AD7606 into one of two power-down modes, Standby mode or
+      Must be the device tree identifier of the STBY pin. This pin is used to
+      place the AD7606 into one of two power-down modes, Standby mode or
       Shutdown mode. As the line is active low, it should be marked
       GPIO_ACTIVE_LOW.
     maxItems: 1
 
   adi,first-data-gpios:
     description:
-      Must be the device tree identifier of the FRSTDATA pin.
-      The FRSTDATA output indicates when the first channel, V1, is
-      being read back on either the parallel, byte or serial interface.
-      As the line is active high, it should be marked GPIO_ACTIVE_HIGH.
+      Must be the device tree identifier of the FRSTDATA pin.  The FRSTDATA
+      output indicates when the first channel, V1, is being read back on either
+      the parallel, byte or serial interface.  As the line is active high, it
+      should be marked GPIO_ACTIVE_HIGH.
     maxItems: 1
 
   adi,range-gpios:
     description:
-      Must be the device tree identifier of the RANGE pin. The polarity on
-      this pin determines the input range of the analog input channels. If
-      this pin is tied to a logic high, the analog input range is ±10V for
-      all channels. If this pin is tied to a logic low, the analog input range
-      is ±5V for all channels. As the line is active high, it should be marked
+      Must be the device tree identifier of the RANGE pin. The polarity on this
+      pin determines the input range of the analog input channels. If this pin
+      is tied to a logic high, the analog input range is ±10V for all channels.
+      If this pin is tied to a logic low, the analog input range is ±5V for all
+      channels. As the line is active high, it should be marked
       GPIO_ACTIVE_HIGH.
     maxItems: 1
 
   adi,oversampling-ratio-gpios:
     description:
-      Must be the device tree identifier of the over-sampling
-      mode pins. As the line is active high, it should be marked
-      GPIO_ACTIVE_HIGH.
+      Must be the device tree identifier of the over-sampling mode pins. As the
+      line is active high, it should be marked GPIO_ACTIVE_HIGH.
     maxItems: 3
 
   adi,sw-mode:
     description:
       Software mode of operation, so far available only for ad7616 and ad7606b.
-      It is enabled when all three oversampling mode pins are connected to
-      high level. The device is configured by the corresponding registers. If the
-      adi,oversampling-ratio-gpios property is defined, then the driver will set the
-      oversampling gpios to high. Otherwise, it is assumed that the pins are hardwired
-      to VDD.
+      It is enabled when all three oversampling mode pins are connected to high
+      level. The device is configured by the corresponding registers. If the
+      adi,oversampling-ratio-gpios property is defined, then the driver will set
+      the oversampling gpios to high. Otherwise, it is assumed that the pins are
+      hardwired to VDD.
     type: boolean
 
 required:

@@ -36,6 +36,9 @@ properties:
   avcc-supply: true
 
   interrupts:
+    description:
+      The BUSY pin falling edge indicates that the conversion is over, and thus
+      new data is available.
     maxItems: 1
 
   adi,conversion-start-gpios:

@@ -48,8 +51,9 @@ properties:
   reset-gpios:
     description:
       Must be the device tree identifier of the RESET pin. If specified, it will
-      be asserted during driver probe. As the line is active high, it should be
-      marked GPIO_ACTIVE_HIGH.
+      be asserted during driver probe. On the AD7606x, as the line is active
+      high, it should be marked GPIO_ACTIVE_HIGH. On the AD7616, as the line is
+      active low, it should be marked GPIO_ACTIVE_LOW.
     maxItems: 1
 
   standby-gpios:

@@ -62,36 +66,39 @@ properties:
 
   adi,first-data-gpios:
     description:
-      Must be the device tree identifier of the FRSTDATA pin.  The FRSTDATA
+      Must be the device tree identifier of the FRSTDATA pin. The FRSTDATA
       output indicates when the first channel, V1, is being read back on either
-      the parallel, byte or serial interface.  As the line is active high, it
+      the parallel, byte or serial interface. As the line is active high, it
       should be marked GPIO_ACTIVE_HIGH.
     maxItems: 1
 
   adi,range-gpios:
     description:
-      Must be the device tree identifier of the RANGE pin. The polarity on this
+      Must be the device tree identifier of the RANGE pin. The state on this
       pin determines the input range of the analog input channels. If this pin
       is tied to a logic high, the analog input range is ±10V for all channels.
-      If this pin is tied to a logic low, the analog input range is ±5V for all
-      channels. As the line is active high, it should be marked
+      On the AD760X, if this pin is tied to a logic low, the analog input range
+      is ±5V for all channels. As the line is active high, it should be marked
       GPIO_ACTIVE_HIGH.
     maxItems: 1
 
   adi,oversampling-ratio-gpios:
     description:
       Must be the device tree identifier of the over-sampling mode pins. As the
-      line is active high, it should be marked GPIO_ACTIVE_HIGH.
+      line is active high, it should be marked GPIO_ACTIVE_HIGH. On the AD7606X
+      parts that support it, if all 3 pins are tied to a logic high, software
+      mode is enabled.
     maxItems: 3
 
   adi,sw-mode:
     description:
-      Software mode of operation, so far available only for ad7616 and ad7606b.
+      Software mode of operation, so far available only for AD7616 and AD7606b.
       It is enabled when all three oversampling mode pins are connected to high
-      level. The device is configured by the corresponding registers. If the
-      adi,oversampling-ratio-gpios property is defined, then the driver will set
-      the oversampling gpios to high. Otherwise, it is assumed that the pins are
-      hardwired to VDD.
+      level for the AD7606B, or all two range selection pins are connected to
+      high level for the AD7616. The device is configured by the corresponding
+      registers. If the adi,oversampling-ratio-gpios property is defined, then
+      the driver will set the oversampling gpios to high. Otherwise, it is
+      assumed that the pins are hardwired to VDD.
     type: boolean
 
 required:

@@ -153,7 +153,6 @@ examples:
                                            <&gpio 23 GPIO_ACTIVE_HIGH>,
                                            <&gpio 26 GPIO_ACTIVE_HIGH>;
             standby-gpios = <&gpio 24 GPIO_ACTIVE_LOW>;
-            adi,sw-mode;
         };
     };
 ...

@@ -35,6 +35,15 @@ properties:
 
   avcc-supply: true
 
+  vdrive-supply:
+    description:
+      Determines the voltage level at which the interface logic pins will
+      operate.
+
+  refin-supply:
+    description:
+      The voltage supply for optional external reference voltage.
+
   interrupts:
     description:
       The BUSY pin falling edge indicates that the conversion is over, and thus

@@ -106,9 +115,11 @@ required:
   - reg
   - spi-cpha
   - avcc-supply
+  - vdrive-supply
   - interrupts
   - adi,conversion-start-gpios
 
+
 allOf:
   - $ref: /schemas/spi/spi-peripheral-props.yaml#
 

@@ -130,6 +141,7 @@ examples:
             spi-cpha;
 
             avcc-supply = <&adc_vref>;
+            vdrive-supply = <&vdd_supply>;
 
             interrupts = <25 IRQ_TYPE_EDGE_FALLING>;
             interrupt-parent = <&gpio>;

@@ -52,10 +52,11 @@ properties:
 
   adi,conversion-start-gpios:
     description:
-      Must be the device tree identifier of the CONVST pin. This logic input is
-      used to initiate conversions on the analog input channels. As the line is
-      active high, it should be marked GPIO_ACTIVE_HIGH.
-    maxItems: 1
+      Must be the device tree identifier of the CONVST pin(s). This logic input
+      is used to initiate conversions on the analog input channels. As the line
+      is active high, it should be marked GPIO_ACTIVE_HIGH.
+    minItems: 1
+    maxItems: 2
 
   reset-gpios:
     description:

@@ -88,8 +89,11 @@ properties:
       is tied to a logic high, the analog input range is ±10V for all channels.
       On the AD760X, if this pin is tied to a logic low, the analog input range
       is ±5V for all channels. As the line is active high, it should be marked
-      GPIO_ACTIVE_HIGH.
-    maxItems: 1
+      GPIO_ACTIVE_HIGH. On the AD7616, there are 2 pins, and if the 2 pins are
+      tied to a logic high, software mode is enabled, otherwise one of the 3
+      possible range values is selected.
+    minItems: 1
+    maxItems: 2
 
   adi,oversampling-ratio-gpios:
     description:

@@ -123,6 +127,50 @@ required:
 allOf:
   - $ref: /schemas/spi/spi-peripheral-props.yaml#
 
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: adi,ad7616
+    then:
+      properties:
+        adi,first-data-gpios: false
+        standby-gpios: false
+        adi,range-gpios:
+          maxItems: 2
+    else:
+      properties:
+        adi,range-gpios:
+          maxItems: 1
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - adi,ad7605-4
+              - adi,ad7616
+    then:
+      properties:
+        adi,oversampling-ratio-gpios: false
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - adi,ad7605-4
+              - adi,ad7606-4
+              - adi,ad7606-6
+              - adi,ad7606-8
+    then:
+      properties:
+        adi,sw-mode: false
+    else:
+      properties:
+        adi,conversion-start-gpios:
+          maxItems: 1
+
 unevaluatedProperties: false
 
 examples:

@@ -236,9 +236,9 @@ static int ad7606_write_os_hw(struct iio_dev *indio_dev, int val)
 	struct ad7606_state *st = iio_priv(indio_dev);
 	DECLARE_BITMAP(values, 3);
 
-	values[0] = val;
+	values[0] = val & GENMASK(2, 0);
 
-	gpiod_set_array_value(ARRAY_SIZE(values), st->gpio_os->desc,
+	gpiod_set_array_value(st->gpio_os->ndescs, st->gpio_os->desc,
 			      st->gpio_os->info, values);
 
 	/* AD7616 requires a reset to update value */

@@ -249,8 +249,9 @@ static int ad7616_sw_mode_config(struct iio_dev *indio_dev)
 static int ad7606B_sw_mode_config(struct iio_dev *indio_dev)
 {
 	struct ad7606_state *st = iio_priv(indio_dev);
-	unsigned long os[3] = {1};
+	DECLARE_BITMAP(os, 3);
 
+	bitmap_fill(os, 3);
 	/*
 	 * Software mode is enabled when all three oversampling
 	 * pins are set to high. If oversampling gpios are defined

@@ -258,7 +259,7 @@ static int ad7606B_sw_mode_config(struct iio_dev *indio_dev)
 	 * otherwise, they must be hardwired to VDD
 	 */
 	if (st->gpio_os) {
-		gpiod_set_array_value(ARRAY_SIZE(os),
+		gpiod_set_array_value(st->gpio_os->ndescs,
 				      st->gpio_os->desc, st->gpio_os->info, os);
 	}
 	/* OS of 128 and 256 are available only in software mode */

@@ -443,7 +443,7 @@ static int ad7606_request_gpios(struct ad7606_state *st)
 		return PTR_ERR(st->gpio_range);
 
 	st->gpio_standby = devm_gpiod_get_optional(dev, "standby",
-						   GPIOD_OUT_HIGH);
+						   GPIOD_OUT_LOW);
 	if (IS_ERR(st->gpio_standby))
 		return PTR_ERR(st->gpio_standby);
 

@@ -686,7 +686,7 @@ static int ad7606_suspend(struct device *dev)
 
 	if (st->gpio_standby) {
 		gpiod_set_value(st->gpio_range, 1);
-		gpiod_set_value(st->gpio_standby, 0);
+		gpiod_set_value(st->gpio_standby, 1);
 	}
 
 	return 0;

@@ -69,19 +69,17 @@ static int ad7606_reg_access(struct iio_dev *indio_dev,
 	struct ad7606_state *st = iio_priv(indio_dev);
 	int ret;
 
-	mutex_lock(&st->lock);
+	guard(mutex)(&st->lock);
+
 	if (readval) {
 		ret = st->bops->reg_read(st, reg);
 		if (ret < 0)
-			goto err_unlock;
+			return ret;
 		*readval = ret;
-		ret = 0;
+		return 0;
 	} else {
-		ret = st->bops->reg_write(st, reg, writeval);
+		return st->bops->reg_write(st, reg, writeval);
 	}
-err_unlock:
-	mutex_unlock(&st->lock);
-	return ret;
 }
 
 static int ad7606_read_samples(struct ad7606_state *st)

@@ -124,18 +122,18 @@ static irqreturn_t ad7606_trigger_handler(int irq, void *p)
 	struct ad7606_state *st = iio_priv(indio_dev);
 	int ret;
 
-	mutex_lock(&st->lock);
+	scoped_guard(mutex, &st->lock) {
+		ret = ad7606_read_samples(st);
+		if (ret)
+			goto error_ret;
 
-	ret = ad7606_read_samples(st);
-	if (ret == 0)
 		iio_push_to_buffers_with_timestamp(indio_dev, st->data,
 						   iio_get_time_ns(indio_dev));
-
-	iio_trigger_notify_done(indio_dev->trig);
-	/* The rising edge of the CONVST signal starts a new conversion. */
-	gpiod_set_value(st->gpio_convst, 1);
-
-	mutex_unlock(&st->lock);
+error_ret:
+		iio_trigger_notify_done(indio_dev->trig);
+		/* The rising edge of the CONVST signal starts a new conversion. */
+		gpiod_set_value(st->gpio_convst, 1);
+	}
 
 	return IRQ_HANDLED;
 }

@@ -259,17 +257,15 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
 
 	switch (mask) {
 	case IIO_CHAN_INFO_SCALE:
-		mutex_lock(&st->lock);
-		i = find_closest(val2, st->scale_avail, st->num_scales);
-		if (st->sw_mode_en)
-			ch = chan->address;
-		ret = st->write_scale(indio_dev, ch, i);
-		if (ret < 0) {
-			mutex_unlock(&st->lock);
-			return ret;
+		scoped_guard(mutex, &st->lock) {
+			i = find_closest(val2, st->scale_avail, st->num_scales);
+			if (st->sw_mode_en)
+				ch = chan->address;
+			ret = st->write_scale(indio_dev, ch, i);
+			if (ret < 0)
+				return ret;
+			st->range[ch] = i;
 		}
-		st->range[ch] = i;
-		mutex_unlock(&st->lock);
 
 		return 0;
 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:

@@ -277,14 +273,12 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
 			return -EINVAL;
 		i = find_closest(val, st->oversampling_avail,
 				 st->num_os_ratios);
-		mutex_lock(&st->lock);
-		ret = st->write_os(indio_dev, i);
-		if (ret < 0) {
-			mutex_unlock(&st->lock);
-			return ret;
+		scoped_guard(mutex, &st->lock) {
+			ret = st->write_os(indio_dev, i);
+			if (ret < 0)
+				return ret;
+			st->oversampling = st->oversampling_avail[i];
 		}
-		st->oversampling = st->oversampling_avail[i];
-		mutex_unlock(&st->lock);
 
 		return 0;
 	default: