[PATCH] iio:adc:ad7923: Add support for the ad7908/ad7918/ad7928

[Daniel Junho <djunho@gmail.com>]

The ad7928 is software compatible with the ad7923. The ad7908 and ad7918 are the
8 and 10 bit version of the ad7928.

Signed-off-by: Daniel Junho <djunho@gmail.com>
---
 drivers/iio/adc/Kconfig  |  3 +-
 drivers/iio/adc/ad7923.c | 96 +++++++++++++++++++++++++++++++---------
 2 files changed, 78 insertions(+), 21 deletions(-)

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 976567d4dbef..40aa05fbf85e 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -205,7 +205,8 @@ config AD7923
 	select IIO_TRIGGERED_BUFFER
 	help
 	  Say yes here to build support for Analog Devices
-	  AD7904, AD7914, AD7923, AD7924 4 Channel ADCs.
+	  AD7904, AD7914, AD7923, AD7924 4 Channel ADCs, and
+	  AD7908, AD7918, AD7928 8 Channels ADCs.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called ad7923.
diff --git a/drivers/iio/adc/ad7923.c b/drivers/iio/adc/ad7923.c
index 3212eb4c0f25..f08a5218dad1 100644
--- a/drivers/iio/adc/ad7923.c
+++ b/drivers/iio/adc/ad7923.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * AD7904/AD7914/AD7923/AD7924 SPI ADC driver
+ * AD7904/AD7914/AD7923/AD7924/AD7908/AD7918/AD7928 SPI ADC driver
  *
  * Copyright 2011 Analog Devices Inc (from AD7923 Driver)
  * Copyright 2012 CS Systemes d'Information
@@ -26,23 +26,32 @@
 #define AD7923_WRITE_CR		BIT(11)		/* write control register */
 #define AD7923_RANGE		BIT(1)		/* range to REFin */
 #define AD7923_CODING		BIT(0)		/* coding is straight binary */
+
 #define AD7923_PM_MODE_AS	(1)		/* auto shutdown */
 #define AD7923_PM_MODE_FS	(2)		/* full shutdown */
 #define AD7923_PM_MODE_OPS	(3)		/* normal operation */
+
 #define AD7923_CHANNEL_0	(0)		/* analog input 0 */
 #define AD7923_CHANNEL_1	(1)		/* analog input 1 */
 #define AD7923_CHANNEL_2	(2)		/* analog input 2 */
 #define AD7923_CHANNEL_3	(3)		/* analog input 3 */
-#define AD7923_SEQUENCE_OFF	(0)		/* no sequence fonction */
-#define AD7923_SEQUENCE_PROTECT	(2)		/* no interrupt write cycle */
-#define AD7923_SEQUENCE_ON	(3)		/* continuous sequence */
-
-#define AD7923_MAX_CHAN		4
+#define AD7923_CHANNEL_4	(4)		/* analog input 4 */
+#define AD7923_CHANNEL_5	(5)		/* analog input 5 */
+#define AD7923_CHANNEL_6	(6)		/* analog input 6 */
+#define AD7923_CHANNEL_7	(7)		/* analog input 7 */
+
+#define AD7923_SEQUENCE_OFF	(0x00)		/* no sequence function */
+#define AD7923_SEQUENCE_SHADOW	(0x01)		/* use the shadow register
+						 * for programming
+						 * (only AD7908/7918/7928)
+						 */
+#define AD7923_SEQUENCE_PROTECT	(0x10)		/* no interrupt write cycle */
+#define AD7923_SEQUENCE_ON	(0x11)		/* continuous sequence */
 
 #define AD7923_PM_MODE_WRITE(mode)	((mode) << 4)	 /* write mode */
 #define AD7923_CHANNEL_WRITE(channel)	((channel) << 6) /* write channel */
-#define AD7923_SEQUENCE_WRITE(sequence)	((((sequence) & 1) << 3) \
-					+ (((sequence) & 2) << 9))
+#define AD7923_SEQUENCE_WRITE(sequence)	((((sequence) & 0x01) << 3) \
+					+ (((sequence) & 0x10) << 9))
 						/* write sequence fonction */
 /* left shift for CR : bit 11 transmit in first */
 #define AD7923_SHIFT_REGISTER	4
@@ -78,6 +87,9 @@ enum ad7923_id {
 	AD7904,
 	AD7914,
 	AD7924,
+	AD7908,
+	AD7918,
+	AD7928
 };
 
 #define AD7923_V_CHAN(index, bits)					\
@@ -97,7 +109,7 @@ enum ad7923_id {
 		},							\
 	}
 
-#define DECLARE_AD7923_CHANNELS(name, bits) \
+#define DECLARE_AD7923_4CHANNELS(name, bits) \
 const struct iio_chan_spec name ## _channels[] = { \
 	AD7923_V_CHAN(0, bits), \
 	AD7923_V_CHAN(1, bits), \
@@ -106,9 +118,25 @@ const struct iio_chan_spec name ## _channels[] = { \
 	IIO_CHAN_SOFT_TIMESTAMP(4), \
 }
 
-static DECLARE_AD7923_CHANNELS(ad7904, 8);
-static DECLARE_AD7923_CHANNELS(ad7914, 10);
-static DECLARE_AD7923_CHANNELS(ad7924, 12);
+#define DECLARE_AD7923_8CHANNELS(name, bits) \
+const struct iio_chan_spec name ## _channels[] = { \
+	AD7923_V_CHAN(0, bits), \
+	AD7923_V_CHAN(1, bits), \
+	AD7923_V_CHAN(2, bits), \
+	AD7923_V_CHAN(3, bits), \
+	AD7923_V_CHAN(4, bits), \
+	AD7923_V_CHAN(5, bits), \
+	AD7923_V_CHAN(6, bits), \
+	AD7923_V_CHAN(7, bits), \
+	IIO_CHAN_SOFT_TIMESTAMP(8), \
+}
+
+static DECLARE_AD7923_4CHANNELS(ad7904, 8);
+static DECLARE_AD7923_4CHANNELS(ad7914, 10);
+static DECLARE_AD7923_4CHANNELS(ad7924, 12);
+static DECLARE_AD7923_8CHANNELS(ad7908, 8);
+static DECLARE_AD7923_8CHANNELS(ad7918, 10);
+static DECLARE_AD7923_8CHANNELS(ad7928, 12);
 
 static const struct ad7923_chip_info ad7923_chip_info[] = {
 	[AD7904] = {
@@ -123,6 +151,18 @@ static const struct ad7923_chip_info ad7923_chip_info[] = {
 		.channels = ad7924_channels,
 		.num_channels = ARRAY_SIZE(ad7924_channels),
 	},
+	[AD7908] = {
+		.channels = ad7908_channels,
+		.num_channels = ARRAY_SIZE(ad7908_channels),
+	},
+	[AD7918] = {
+		.channels = ad7918_channels,
+		.num_channels = ARRAY_SIZE(ad7918_channels),
+	},
+	[AD7928] = {
+		.channels = ad7928_channels,
+		.num_channels = ARRAY_SIZE(ad7928_channels),
+	},
 };
 
 /**
@@ -135,10 +175,10 @@ static int ad7923_update_scan_mode(struct iio_dev *indio_dev,
 	int i, cmd, len;
 
 	len = 0;
-	for_each_set_bit(i, active_scan_mask, AD7923_MAX_CHAN) {
+	for_each_set_bit(i, active_scan_mask, indio_dev->num_channels - 1) {
 		cmd = AD7923_WRITE_CR | AD7923_CHANNEL_WRITE(i) |
-			AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) |
-			st->settings;
+		      AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) |
+		      st->settings;
 		cmd <<= AD7923_SHIFT_REGISTER;
 		st->tx_buf[len++] = cpu_to_be16(cmd);
 	}
@@ -188,13 +228,13 @@ static irqreturn_t ad7923_trigger_handler(int irq, void *p)
 	return IRQ_HANDLED;
 }
 
-static int ad7923_scan_direct(struct ad7923_state *st, unsigned ch)
+static int ad7923_scan_direct(struct ad7923_state *st, unsigned int ch)
 {
 	int ret, cmd;
 
 	cmd = AD7923_WRITE_CR | AD7923_CHANNEL_WRITE(ch) |
-		AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) |
-		st->settings;
+	      AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) |
+	      st->settings;
 	cmd <<= AD7923_SHIFT_REGISTER;
 	st->tx_buf[0] = cpu_to_be16(cmd);
 
@@ -280,7 +320,7 @@ static int ad7923_probe(struct spi_device *spi)
 
 	st->spi = spi;
 	st->settings = AD7923_CODING | AD7923_RANGE |
-			AD7923_PM_MODE_WRITE(AD7923_PM_MODE_OPS);
+		       AD7923_PM_MODE_WRITE(AD7923_PM_MODE_OPS);
 
 	info = &ad7923_chip_info[spi_get_device_id(spi)->driver_data];
 
@@ -348,13 +388,29 @@ static const struct spi_device_id ad7923_id[] = {
 	{"ad7914", AD7914},
 	{"ad7923", AD7924},
 	{"ad7924", AD7924},
+	{"ad7908", AD7908},
+	{"ad7918", AD7918},
+	{"ad7928", AD7928},
 	{}
 };
 MODULE_DEVICE_TABLE(spi, ad7923_id);
 
+static const struct of_device_id ad7923_of_match[] = {
+	{ .compatible = "adi,ad7904", },
+	{ .compatible = "adi,ad7914", },
+	{ .compatible = "adi,ad7923", },
+	{ .compatible = "adi,ad7924", },
+	{ .compatible = "adi,ad7908", },
+	{ .compatible = "adi,ad7918", },
+	{ .compatible = "adi,ad7928", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, ad7923_of_match);
+
 static struct spi_driver ad7923_driver = {
 	.driver = {
 		.name	= "ad7923",
+		.of_match_table = ad7923_of_match,
 	},
 	.probe		= ad7923_probe,
 	.remove		= ad7923_remove,
@@ -364,5 +420,5 @@ module_spi_driver(ad7923_driver);
 
 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
 MODULE_AUTHOR("Patrick Vasseur <patrick.vasseur@c-s.fr>");
-MODULE_DESCRIPTION("Analog Devices AD7904/AD7914/AD7923/AD7924 ADC");
+MODULE_DESCRIPTION("Analog Devices AD7904/AD7914/AD7923/AD7924/AD7908/AD7918/AD7928 ADC");
 MODULE_LICENSE("GPL v2");
-- 
2.24.0