iio: adc: ad7606: move software functions into common file

BugLink: https://bugs.launchpad.net/bugs/2115266

[ Upstream commit d2477887f6677de0675e600f1590378a5fb52909 ]

Since the register are always the same, whatever bus is used, moving the
software functions into the main file avoids the code to be duplicated
in both SPI and parallel version of the driver.

Signed-off-by: Guillaume Stols <gstols@baylibre.com>
Co-developed-by: Angelo Dureghello <adureghello@baylibre.com>
Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
Link: https://patch.msgid.link/20250210-wip-bl-ad7606_add_backend_sw_mode-v4-3-160df18b1da7@baylibre.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Stable-dep-of: 5257d80e22bf ("iio: adc: ad7606: check for NULL before calling sw_mode_config()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Manuel Diewald <manuel.diewald@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

Author: gstols

drivers/iio/adc/ad7606.c

@@ -85,6 +85,10 @@ static const unsigned int ad7606_oversampling_avail[7] = {
 	1, 2, 4, 8, 16, 32, 64,
 };
 
+static const unsigned int ad7606b_oversampling_avail[9] = {
+	1, 2, 4, 8, 16, 32, 64, 128, 256,
+};
+
 static const unsigned int ad7616_oversampling_avail[8] = {
 	1, 2, 4, 8, 16, 32, 64, 128,
 };
@@ -187,6 +191,8 @@ static int ad7608_chan_scale_setup(struct iio_dev *indio_dev,
 				   struct iio_chan_spec *chan, int ch);
 static int ad7609_chan_scale_setup(struct iio_dev *indio_dev,
 				   struct iio_chan_spec *chan, int ch);
+static int ad7616_sw_mode_setup(struct iio_dev *indio_dev);
+static int ad7606b_sw_mode_setup(struct iio_dev *indio_dev);
 
 const struct ad7606_chip_info ad7605_4_info = {
 	.channels = ad7605_channels,
@@ -239,6 +245,7 @@ const struct ad7606_chip_info ad7606b_info = {
 	.oversampling_avail = ad7606_oversampling_avail,
 	.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
 	.scale_setup_cb = ad7606_16bit_chan_scale_setup,
+	.sw_setup_cb = ad7606b_sw_mode_setup,
 };
 EXPORT_SYMBOL_NS_GPL(ad7606b_info, "IIO_AD7606");
 
@@ -250,6 +257,7 @@ const struct ad7606_chip_info ad7606c_16_info = {
 	.oversampling_avail = ad7606_oversampling_avail,
 	.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
 	.scale_setup_cb = ad7606c_16bit_chan_scale_setup,
+	.sw_setup_cb = ad7606b_sw_mode_setup,
 };
 EXPORT_SYMBOL_NS_GPL(ad7606c_16_info, "IIO_AD7606");
 
@@ -294,6 +302,7 @@ const struct ad7606_chip_info ad7606c_18_info = {
 	.oversampling_avail = ad7606_oversampling_avail,
 	.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
 	.scale_setup_cb = ad7606c_18bit_chan_scale_setup,
+	.sw_setup_cb = ad7606b_sw_mode_setup,
 };
 EXPORT_SYMBOL_NS_GPL(ad7606c_18_info, "IIO_AD7606");
 
@@ -307,6 +316,7 @@ const struct ad7606_chip_info ad7616_info = {
 	.oversampling_num = ARRAY_SIZE(ad7616_oversampling_avail),
 	.os_req_reset = true,
 	.scale_setup_cb = ad7606_16bit_chan_scale_setup,
+	.sw_setup_cb = ad7616_sw_mode_setup,
 };
 EXPORT_SYMBOL_NS_GPL(ad7616_info, "IIO_AD7606");
 
@@ -1138,16 +1148,118 @@ static const struct iio_trigger_ops ad7606_trigger_ops = {
 	.validate_device = iio_trigger_validate_own_device,
 };
 
-static int ad7606_sw_mode_setup(struct iio_dev *indio_dev)
+static int ad7606_write_mask(struct ad7606_state *st, unsigned int addr,
+			     unsigned long mask, unsigned int val)
+{
+	int readval;
+
+	readval = st->bops->reg_read(st, addr);
+	if (readval < 0)
+		return readval;
+
+	readval &= ~mask;
+	readval |= val;
+
+	return st->bops->reg_write(st, addr, readval);
+}
+
+static int ad7616_write_scale_sw(struct iio_dev *indio_dev, int ch, int val)
 {
 	struct ad7606_state *st = iio_priv(indio_dev);
+	unsigned int ch_addr, mode, ch_index;
 
-	st->sw_mode_en = st->bops->sw_mode_config &&
-			 device_property_present(st->dev, "adi,sw-mode");
-	if (!st->sw_mode_en)
-		return 0;
+	/*
+	 * Ad7616 has 16 channels divided in group A and group B.
+	 * The range of channels from A are stored in registers with address 4
+	 * while channels from B are stored in register with address 6.
+	 * The last bit from channels determines if it is from group A or B
+	 * because the order of channels in iio is 0A, 0B, 1A, 1B...
+	 */
+	ch_index = ch >> 1;
+
+	ch_addr = AD7616_RANGE_CH_ADDR(ch_index);
+
+	if ((ch & 0x1) == 0) /* channel A */
+		ch_addr += AD7616_RANGE_CH_A_ADDR_OFF;
+	else	/* channel B */
+		ch_addr += AD7616_RANGE_CH_B_ADDR_OFF;
+
+	/* 0b01 for 2.5v, 0b10 for 5v and 0b11 for 10v */
+	mode = AD7616_RANGE_CH_MODE(ch_index, ((val + 1) & 0b11));
 
-	indio_dev->info = &ad7606_info_sw_mode;
+	return ad7606_write_mask(st, ch_addr, AD7616_RANGE_CH_MSK(ch_index),
+				 mode);
+}
+
+static int ad7616_write_os_sw(struct iio_dev *indio_dev, int val)
+{
+	struct ad7606_state *st = iio_priv(indio_dev);
+
+	return ad7606_write_mask(st, AD7616_CONFIGURATION_REGISTER,
+				 AD7616_OS_MASK, val << 2);
+}
+
+static int ad7606_write_scale_sw(struct iio_dev *indio_dev, int ch, int val)
+{
+	struct ad7606_state *st = iio_priv(indio_dev);
+
+	return ad7606_write_mask(st, AD7606_RANGE_CH_ADDR(ch),
+				 AD7606_RANGE_CH_MSK(ch),
+				 AD7606_RANGE_CH_MODE(ch, val));
+}
+
+static int ad7606_write_os_sw(struct iio_dev *indio_dev, int val)
+{
+	struct ad7606_state *st = iio_priv(indio_dev);
+
+	return st->bops->reg_write(st, AD7606_OS_MODE, val);
+}
+
+static int ad7616_sw_mode_setup(struct iio_dev *indio_dev)
+{
+	struct ad7606_state *st = iio_priv(indio_dev);
+	int ret;
+
+	/*
+	 * Scale can be configured individually for each channel
+	 * in software mode.
+	 */
+
+	st->write_scale = ad7616_write_scale_sw;
+	st->write_os = &ad7616_write_os_sw;
+
+	ret = st->bops->sw_mode_config(indio_dev);
+	if (ret)
+		return ret;
+
+	/* Activate Burst mode and SEQEN MODE */
+	return ad7606_write_mask(st, AD7616_CONFIGURATION_REGISTER,
+				 AD7616_BURST_MODE | AD7616_SEQEN_MODE,
+				 AD7616_BURST_MODE | AD7616_SEQEN_MODE);
+}
+
+static int ad7606b_sw_mode_setup(struct iio_dev *indio_dev)
+{
+	struct ad7606_state *st = iio_priv(indio_dev);
+	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
+	 * in the device tree, then they need to be set to high,
+	 * otherwise, they must be hardwired to VDD
+	 */
+	if (st->gpio_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 */
+	st->oversampling_avail = ad7606b_oversampling_avail;
+	st->num_os_ratios = ARRAY_SIZE(ad7606b_oversampling_avail);
+
+	st->write_scale = ad7606_write_scale_sw;
+	st->write_os = &ad7606_write_os_sw;
 
 	return st->bops->sw_mode_config(indio_dev);
 }
@@ -1326,9 +1438,12 @@ int ad7606_probe(struct device *dev, int irq, void __iomem *base_address,
 	st->write_scale = ad7606_write_scale_hw;
 	st->write_os = ad7606_write_os_hw;
 
-	ret = ad7606_sw_mode_setup(indio_dev);
-	if (ret)
-		return ret;
+	st->sw_mode_en = st->chip_info->sw_setup_cb &&
+			 device_property_present(st->dev, "adi,sw-mode");
+	if (st->sw_mode_en) {
+		indio_dev->info = &ad7606_info_sw_mode;
+		st->chip_info->sw_setup_cb(indio_dev);
+	}
 
 	ret = ad7606_chan_scales_setup(indio_dev);
 	if (ret)

drivers/iio/adc/ad7606.h

@@ -10,6 +10,36 @@
 
 #define AD760X_MAX_CHANNELS	16
 
+#define AD7616_CONFIGURATION_REGISTER	0x02
+#define AD7616_OS_MASK			GENMASK(4, 2)
+#define AD7616_BURST_MODE		BIT(6)
+#define AD7616_SEQEN_MODE		BIT(5)
+#define AD7616_RANGE_CH_A_ADDR_OFF	0x04
+#define AD7616_RANGE_CH_B_ADDR_OFF	0x06
+/*
+ * Range of channels from a group are stored in 2 registers.
+ * 0, 1, 2, 3 in a register followed by 4, 5, 6, 7 in second register.
+ * For channels from second group(8-15) the order is the same, only with
+ * an offset of 2 for register address.
+ */
+#define AD7616_RANGE_CH_ADDR(ch)	((ch) >> 2)
+/* The range of the channel is stored in 2 bits */
+#define AD7616_RANGE_CH_MSK(ch)		(0b11 << (((ch) & 0b11) * 2))
+#define AD7616_RANGE_CH_MODE(ch, mode)	((mode) << ((((ch) & 0b11)) * 2))
+
+#define AD7606_CONFIGURATION_REGISTER	0x02
+#define AD7606_SINGLE_DOUT		0x00
+
+/*
+ * Range for AD7606B channels are stored in registers starting with address 0x3.
+ * Each register stores range for 2 channels(4 bits per channel).
+ */
+#define AD7606_RANGE_CH_MSK(ch)		(GENMASK(3, 0) << (4 * ((ch) & 0x1)))
+#define AD7606_RANGE_CH_MODE(ch, mode)	\
+	((GENMASK(3, 0) & (mode)) << (4 * ((ch) & 0x1)))
+#define AD7606_RANGE_CH_ADDR(ch)	(0x03 + ((ch) >> 1))
+#define AD7606_OS_MODE			0x08
+
 #define AD760X_CHANNEL(num, mask_sep, mask_type, mask_all, bits) {	\
 		.type = IIO_VOLTAGE,				\
 		.indexed = 1,					\
@@ -71,6 +101,7 @@ struct ad7606_state;
 
 typedef int (*ad7606_scale_setup_cb_t)(struct iio_dev *indio_dev,
 				       struct iio_chan_spec *chan, int ch);
+typedef int (*ad7606_sw_setup_cb_t)(struct iio_dev *indio_dev);
 
 /**
  * struct ad7606_chip_info - chip specific information
@@ -80,6 +111,7 @@ typedef int (*ad7606_scale_setup_cb_t)(struct iio_dev *indio_dev,
  * @num_channels:	number of channels
  * @num_adc_channels	the number of channels the ADC actually inputs.
  * @scale_setup_cb:	callback to setup the scales for each channel
+ * @sw_setup_cb:	callback to setup the software mode if available.
  * @oversampling_avail	pointer to the array which stores the available
  *			oversampling ratios.
  * @oversampling_num	number of elements stored in oversampling_avail array
@@ -94,6 +126,7 @@ struct ad7606_chip_info {
 	unsigned int			num_adc_channels;
 	unsigned int			num_channels;
 	ad7606_scale_setup_cb_t		scale_setup_cb;
+	ad7606_sw_setup_cb_t		sw_setup_cb;
 	const unsigned int		*oversampling_avail;
 	unsigned int			oversampling_num;
 	bool				os_req_reset;
@@ -206,10 +239,6 @@ struct ad7606_bus_ops {
 	int (*reg_write)(struct ad7606_state *st,
 				unsigned int addr,
 				unsigned int val);
-	int (*write_mask)(struct ad7606_state *st,
-				 unsigned int addr,
-				 unsigned long mask,
-				 unsigned int val);
 	int (*update_scan_mode)(struct iio_dev *indio_dev, const unsigned long *scan_mask);
 	u16 (*rd_wr_cmd)(int addr, char isWriteOp);
 };