iio: adc: ad4000: Add support for PulSAR devices

The ADI PulSAR series of single-channel devices comprises differential and
pseudo-differential ADCs that don't require any input data from the host
controller. By not requiring a data input line, PulSAR devices can operate
with a 3-wire only data bus in some setups.

The AD4000 series and the single-channel PulSAR series of devices have
similar SPI transfer specifications and wiring configurations.
Single-channel PulSAR devices are slower than AD4000 and don't have a
configuration register. That taken into account, single-channel PulSARs can
be supported by the ad4000 driver without any increase in code complexity.

Extend the AD4000 driver to also support single-channel PulSAR devices.

Reviewed-by: David Lechner <dlechner@baylibre.com>
Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
Link: https://patch.msgid.link/2bfb904e29914c3dc4905e1c87fcc735575f330d.1733147444.git.marcelo.schmitt@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Author: machschmitt

drivers/iio/adc/ad4000.c

@@ -138,6 +138,48 @@ static const struct ad4000_time_spec ad4020_t_spec = {
 	.t_quiet2_ns = 60,
 };
 
+/* AD7983, AD7984 */
+static const struct ad4000_time_spec ad7983_t_spec = {
+	.t_conv_ns = 500,
+	.t_quiet2_ns = 0,
+};
+
+/* AD7980, AD7982 */
+static const struct ad4000_time_spec ad7980_t_spec = {
+	.t_conv_ns = 800,
+	.t_quiet2_ns = 0,
+};
+
+/* AD7946, AD7686, AD7688, AD7988-5, AD7693 */
+static const struct ad4000_time_spec ad7686_t_spec = {
+	.t_conv_ns = 1600,
+	.t_quiet2_ns = 0,
+};
+
+/* AD7690 */
+static const struct ad4000_time_spec ad7690_t_spec = {
+	.t_conv_ns = 2100,
+	.t_quiet2_ns = 0,
+};
+
+/* AD7942, AD7685, AD7687 */
+static const struct ad4000_time_spec ad7687_t_spec = {
+	.t_conv_ns = 3200,
+	.t_quiet2_ns = 0,
+};
+
+/* AD7691 */
+static const struct ad4000_time_spec ad7691_t_spec = {
+	.t_conv_ns = 3700,
+	.t_quiet2_ns = 0,
+};
+
+/* AD7988-1 */
+static const struct ad4000_time_spec ad7988_1_t_spec = {
+	.t_conv_ns = 9500,
+	.t_quiet2_ns = 0,
+};
+
 struct ad4000_chip_info {
 	const char *dev_name;
 	struct iio_chan_spec chan_spec[2];
@@ -260,6 +302,96 @@ static const struct ad4000_chip_info adaq4003_chip_info = {
 	.has_hardware_gain = true,
 };
 
+static const struct ad4000_chip_info ad7685_chip_info = {
+	.dev_name = "ad7685",
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 0),
+	.time_spec = &ad7687_t_spec,
+};
+
+static const struct ad4000_chip_info ad7686_chip_info = {
+	.dev_name = "ad7686",
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 0),
+	.time_spec = &ad7686_t_spec,
+};
+
+static const struct ad4000_chip_info ad7687_chip_info = {
+	.dev_name = "ad7687",
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 16, 0),
+	.time_spec = &ad7687_t_spec,
+};
+
+static const struct ad4000_chip_info ad7688_chip_info = {
+	.dev_name = "ad7688",
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 16, 0),
+	.time_spec = &ad7686_t_spec,
+};
+
+static const struct ad4000_chip_info ad7690_chip_info = {
+	.dev_name = "ad7690",
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 18, 0),
+	.time_spec = &ad7690_t_spec,
+};
+
+static const struct ad4000_chip_info ad7691_chip_info = {
+	.dev_name = "ad7691",
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 18, 0),
+	.time_spec = &ad7691_t_spec,
+};
+
+static const struct ad4000_chip_info ad7693_chip_info = {
+	.dev_name = "ad7693",
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 16, 0),
+	.time_spec = &ad7686_t_spec,
+};
+
+static const struct ad4000_chip_info ad7942_chip_info = {
+	.dev_name = "ad7942",
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 14, 0),
+	.time_spec = &ad7687_t_spec,
+};
+
+static const struct ad4000_chip_info ad7946_chip_info = {
+	.dev_name = "ad7946",
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 14, 0),
+	.time_spec = &ad7686_t_spec,
+};
+
+static const struct ad4000_chip_info ad7980_chip_info = {
+	.dev_name = "ad7980",
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 0),
+	.time_spec = &ad7980_t_spec,
+};
+
+static const struct ad4000_chip_info ad7982_chip_info = {
+	.dev_name = "ad7982",
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 18, 0),
+	.time_spec = &ad7980_t_spec,
+};
+
+static const struct ad4000_chip_info ad7983_chip_info = {
+	.dev_name = "ad7983",
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 0),
+	.time_spec = &ad7983_t_spec,
+};
+
+static const struct ad4000_chip_info ad7984_chip_info = {
+	.dev_name = "ad7984",
+	.chan_spec = AD4000_DIFF_CHANNELS('s', 18, 0),
+	.time_spec = &ad7983_t_spec,
+};
+
+static const struct ad4000_chip_info ad7988_1_chip_info = {
+	.dev_name = "ad7988-1",
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 0),
+	.time_spec = &ad7988_1_t_spec,
+};
+
+static const struct ad4000_chip_info ad7988_5_chip_info = {
+	.dev_name = "ad7988-5",
+	.chan_spec = AD4000_PSEUDO_DIFF_CHANNELS('u', 16, 0),
+	.time_spec = &ad7686_t_spec,
+};
+
 struct ad4000_state {
 	struct spi_device *spi;
 	struct gpio_desc *cnv_gpio;
@@ -733,6 +865,21 @@ static const struct spi_device_id ad4000_id[] = {
 	{ "ad4022", (kernel_ulong_t)&ad4022_chip_info },
 	{ "adaq4001", (kernel_ulong_t)&adaq4001_chip_info },
 	{ "adaq4003", (kernel_ulong_t)&adaq4003_chip_info },
+	{ "ad7685", (kernel_ulong_t)&ad7685_chip_info },
+	{ "ad7686", (kernel_ulong_t)&ad7686_chip_info },
+	{ "ad7687", (kernel_ulong_t)&ad7687_chip_info },
+	{ "ad7688", (kernel_ulong_t)&ad7688_chip_info },
+	{ "ad7690", (kernel_ulong_t)&ad7690_chip_info },
+	{ "ad7691", (kernel_ulong_t)&ad7691_chip_info },
+	{ "ad7693", (kernel_ulong_t)&ad7693_chip_info },
+	{ "ad7942", (kernel_ulong_t)&ad7942_chip_info },
+	{ "ad7946", (kernel_ulong_t)&ad7946_chip_info },
+	{ "ad7980", (kernel_ulong_t)&ad7980_chip_info },
+	{ "ad7982", (kernel_ulong_t)&ad7982_chip_info },
+	{ "ad7983", (kernel_ulong_t)&ad7983_chip_info },
+	{ "ad7984", (kernel_ulong_t)&ad7984_chip_info },
+	{ "ad7988-1", (kernel_ulong_t)&ad7988_1_chip_info },
+	{ "ad7988-5", (kernel_ulong_t)&ad7988_5_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(spi, ad4000_id);
@@ -754,6 +901,21 @@ static const struct of_device_id ad4000_of_match[] = {
 	{ .compatible = "adi,ad4022", .data = &ad4022_chip_info },
 	{ .compatible = "adi,adaq4001", .data = &adaq4001_chip_info },
 	{ .compatible = "adi,adaq4003", .data = &adaq4003_chip_info },
+	{ .compatible = "adi,ad7685", .data = &ad7685_chip_info },
+	{ .compatible = "adi,ad7686", .data = &ad7686_chip_info },
+	{ .compatible = "adi,ad7687", .data = &ad7687_chip_info },
+	{ .compatible = "adi,ad7688", .data = &ad7688_chip_info },
+	{ .compatible = "adi,ad7690", .data = &ad7690_chip_info },
+	{ .compatible = "adi,ad7691", .data = &ad7691_chip_info },
+	{ .compatible = "adi,ad7693", .data = &ad7693_chip_info },
+	{ .compatible = "adi,ad7942", .data = &ad7942_chip_info },
+	{ .compatible = "adi,ad7946", .data = &ad7946_chip_info },
+	{ .compatible = "adi,ad7980", .data = &ad7980_chip_info },
+	{ .compatible = "adi,ad7982", .data = &ad7982_chip_info },
+	{ .compatible = "adi,ad7983", .data = &ad7983_chip_info },
+	{ .compatible = "adi,ad7984", .data = &ad7984_chip_info },
+	{ .compatible = "adi,ad7988-1", .data = &ad7988_1_chip_info },
+	{ .compatible = "adi,ad7988-5", .data = &ad7988_5_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, ad4000_of_match);