iio: adc: ad7380: add support for ad738x-4 4 channels variants

Add support for ad7380/1/2/3-4 parts which are 4 channels
variants from ad7380/1/2/3
Signed-off-by: Julien Stephan <jstephan@baylibre.com>
Link: https://lore.kernel.org/r/20240528-adding-new-ad738x-driver-v7-7-4cd70a4c12c8@baylibre.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/adc/ad7380.c

@@ -8,6 +8,9 @@
  * Datasheets of supported parts:
  * ad7380/1 : https://www.analog.com/media/en/technical-documentation/data-sheets/AD7380-7381.pdf
  * ad7383/4 : https://www.analog.com/media/en/technical-documentation/data-sheets/ad7383-7384.pdf
+ * ad7380-4 : https://www.analog.com/media/en/technical-documentation/data-sheets/ad7380-4.pdf
+ * ad7381-4 : https://www.analog.com/media/en/technical-documentation/data-sheets/ad7381-4.pdf
+ * ad7383/4-4 : https://www.analog.com/media/en/technical-documentation/data-sheets/ad7383-4-ad7384-4.pdf
  */
 
 #include <linux/bitfield.h>
@@ -27,7 +30,7 @@
 #include <linux/iio/trigger_consumer.h>
 #include <linux/iio/triggered_buffer.h>
 
-#define MAX_NUM_CHANNELS		2
+#define MAX_NUM_CHANNELS		4
 /* 2.5V internal reference voltage */
 #define AD7380_INTERNAL_REF_MV		2500
 
@@ -104,27 +107,53 @@ static const struct iio_chan_spec name[] = {		\
 	IIO_CHAN_SOFT_TIMESTAMP(2),			\
 }
 
+#define DEFINE_AD7380_4_CHANNEL(name, bits, diff)	\
+static const struct iio_chan_spec name[] = {		\
+	AD7380_CHANNEL(0, bits, diff),			\
+	AD7380_CHANNEL(1, bits, diff),			\
+	AD7380_CHANNEL(2, bits, diff),			\
+	AD7380_CHANNEL(3, bits, diff),			\
+	IIO_CHAN_SOFT_TIMESTAMP(4),			\
+}
+
 /* fully differential */
 DEFINE_AD7380_2_CHANNEL(ad7380_channels, 16, 1);
 DEFINE_AD7380_2_CHANNEL(ad7381_channels, 14, 1);
+DEFINE_AD7380_4_CHANNEL(ad7380_4_channels, 16, 1);
+DEFINE_AD7380_4_CHANNEL(ad7381_4_channels, 14, 1);
 /* pseudo differential */
 DEFINE_AD7380_2_CHANNEL(ad7383_channels, 16, 0);
 DEFINE_AD7380_2_CHANNEL(ad7384_channels, 14, 0);
+DEFINE_AD7380_4_CHANNEL(ad7383_4_channels, 16, 0);
+DEFINE_AD7380_4_CHANNEL(ad7384_4_channels, 14, 0);
 
 static const char * const ad7380_2_channel_vcm_supplies[] = {
 	"aina", "ainb",
 };
 
+static const char * const ad7380_4_channel_vcm_supplies[] = {
+	"aina", "ainb", "ainc", "aind",
+};
+
 /* Since this is simultaneous sampling, we don't allow individual channels. */
 static const unsigned long ad7380_2_channel_scan_masks[] = {
 	GENMASK(1, 0),
 	0
 };
 
+static const unsigned long ad7380_4_channel_scan_masks[] = {
+	GENMASK(3, 0),
+	0
+};
+
 static const struct ad7380_timing_specs ad7380_timing = {
 	.t_csh_ns = 10,
 };
 
+static const struct ad7380_timing_specs ad7380_4_timing = {
+	.t_csh_ns = 20,
+};
+
 static const struct ad7380_chip_info ad7380_chip_info = {
 	.name = "ad7380",
 	.channels = ad7380_channels,
@@ -161,6 +190,42 @@ static const struct ad7380_chip_info ad7384_chip_info = {
 	.timing_specs = &ad7380_timing,
 };
 
+static const struct ad7380_chip_info ad7380_4_chip_info = {
+	.name = "ad7380-4",
+	.channels = ad7380_4_channels,
+	.num_channels = ARRAY_SIZE(ad7380_4_channels),
+	.available_scan_masks = ad7380_4_channel_scan_masks,
+	.timing_specs = &ad7380_4_timing,
+};
+
+static const struct ad7380_chip_info ad7381_4_chip_info = {
+	.name = "ad7381-4",
+	.channels = ad7381_4_channels,
+	.num_channels = ARRAY_SIZE(ad7381_4_channels),
+	.available_scan_masks = ad7380_4_channel_scan_masks,
+	.timing_specs = &ad7380_4_timing,
+};
+
+static const struct ad7380_chip_info ad7383_4_chip_info = {
+	.name = "ad7383-4",
+	.channels = ad7383_4_channels,
+	.num_channels = ARRAY_SIZE(ad7383_4_channels),
+	.vcm_supplies = ad7380_4_channel_vcm_supplies,
+	.num_vcm_supplies = ARRAY_SIZE(ad7380_4_channel_vcm_supplies),
+	.available_scan_masks = ad7380_4_channel_scan_masks,
+	.timing_specs = &ad7380_4_timing,
+};
+
+static const struct ad7380_chip_info ad7384_4_chip_info = {
+	.name = "ad7384-4",
+	.channels = ad7384_4_channels,
+	.num_channels = ARRAY_SIZE(ad7384_4_channels),
+	.vcm_supplies = ad7380_4_channel_vcm_supplies,
+	.num_vcm_supplies = ARRAY_SIZE(ad7380_4_channel_vcm_supplies),
+	.available_scan_masks = ad7380_4_channel_scan_masks,
+	.timing_specs = &ad7380_4_timing,
+};
+
 struct ad7380_state {
 	const struct ad7380_chip_info *chip_info;
 	struct spi_device *spi;
@@ -172,7 +237,7 @@ struct ad7380_state {
 	 * transfer buffers to live in their own cache lines.
 	 * Make the buffer large enough for MAX_NUM_CHANNELS 16-bit samples and one 64-bit
 	 * aligned 64 bit timestamp.
-	 * As MAX_NUM_CHANNELS is 2 the layout of the structure is the same for all parts
+	 * As MAX_NUM_CHANNELS is 4 the layout of the structure is the same for all parts
 	 */
 	struct {
 		u16 raw[MAX_NUM_CHANNELS];
@@ -512,6 +577,10 @@ static const struct of_device_id ad7380_of_match_table[] = {
 	{ .compatible = "adi,ad7381", .data = &ad7381_chip_info },
 	{ .compatible = "adi,ad7383", .data = &ad7383_chip_info },
 	{ .compatible = "adi,ad7384", .data = &ad7384_chip_info },
+	{ .compatible = "adi,ad7380-4", .data = &ad7380_4_chip_info },
+	{ .compatible = "adi,ad7381-4", .data = &ad7381_4_chip_info },
+	{ .compatible = "adi,ad7383-4", .data = &ad7383_4_chip_info },
+	{ .compatible = "adi,ad7384-4", .data = &ad7384_4_chip_info },
 	{ }
 };
 
@@ -520,6 +589,10 @@ static const struct spi_device_id ad7380_id_table[] = {
 	{ "ad7381", (kernel_ulong_t)&ad7381_chip_info },
 	{ "ad7383", (kernel_ulong_t)&ad7383_chip_info },
 	{ "ad7384", (kernel_ulong_t)&ad7384_chip_info },
+	{ "ad7380-4", (kernel_ulong_t)&ad7380_4_chip_info },
+	{ "ad7381-4", (kernel_ulong_t)&ad7381_4_chip_info },
+	{ "ad7383-4", (kernel_ulong_t)&ad7383_4_chip_info },
+	{ "ad7384-4", (kernel_ulong_t)&ad7384_4_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(spi, ad7380_id_table);