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From: Aidan MacDonald <aidanmacdonald.0x0@gmail.com>
To: linus.walleij@linaro.org, brgl@bgdev.pl, robh+dt@kernel.org,
	krzysztof.kozlowski+dt@linaro.org, wens@csie.org,
	jic23@kernel.org, lee.jones@linaro.org, sre@kernel.org,
	broonie@kernel.org, gregkh@linuxfoundation.org,
	lgirdwood@gmail.com
Cc: lars@metafoo.de, rafael@kernel.org, linux-gpio@vger.kernel.org,
	devicetree@vger.kernel.org, linux-iio@vger.kernel.org,
	linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 08/10] iio: adc: axp20x_adc: Add support for AXP192
Date: Fri,  3 Jun 2022 14:57:12 +0100	[thread overview]
Message-ID: <20220603135714.12007-9-aidanmacdonald.0x0@gmail.com> (raw)
In-Reply-To: <20220603135714.12007-1-aidanmacdonald.0x0@gmail.com>

The AXP192 is identical to the AXP20x, except for the addition of
two more GPIO ADC channels.

Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@gmail.com>
---
 drivers/iio/adc/axp20x_adc.c | 289 +++++++++++++++++++++++++++++++++--
 1 file changed, 280 insertions(+), 9 deletions(-)

diff --git a/drivers/iio/adc/axp20x_adc.c b/drivers/iio/adc/axp20x_adc.c
index 53bf7d4899d2..7d2bf9529420 100644
--- a/drivers/iio/adc/axp20x_adc.c
+++ b/drivers/iio/adc/axp20x_adc.c
@@ -21,6 +21,9 @@
 #include <linux/iio/machine.h>
 #include <linux/mfd/axp20x.h>
 
+#define AXP192_ADC_EN1_MASK			GENMASK(7, 0)
+#define AXP192_ADC_EN2_MASK			(BIT(7) | GENMASK(3, 0))
+
 #define AXP20X_ADC_EN1_MASK			GENMASK(7, 0)
 
 #define AXP20X_ADC_EN2_MASK			(GENMASK(3, 2) | BIT(7))
@@ -31,6 +34,15 @@
 #define AXP20X_GPIO10_IN_RANGE_GPIO0_VAL(x)	((x) & BIT(0))
 #define AXP20X_GPIO10_IN_RANGE_GPIO1_VAL(x)	(((x) & BIT(0)) << 1)
 
+#define AXP192_GPIO30_IN_RANGE_GPIO0		BIT(0)
+#define AXP192_GPIO30_IN_RANGE_GPIO1		BIT(1)
+#define AXP192_GPIO30_IN_RANGE_GPIO2		BIT(2)
+#define AXP192_GPIO30_IN_RANGE_GPIO3		BIT(3)
+#define AXP192_GPIO30_IN_RANGE_GPIO0_VAL(x)	((x) & BIT(0))
+#define AXP192_GPIO30_IN_RANGE_GPIO1_VAL(x)	(((x) & BIT(0)) << 1)
+#define AXP192_GPIO30_IN_RANGE_GPIO2_VAL(x)	(((x) & BIT(0)) << 2)
+#define AXP192_GPIO30_IN_RANGE_GPIO3_VAL(x)	(((x) & BIT(0)) << 3)
+
 #define AXP20X_ADC_RATE_MASK			GENMASK(7, 6)
 #define AXP813_V_I_ADC_RATE_MASK		GENMASK(5, 4)
 #define AXP813_ADC_RATE_MASK			(AXP20X_ADC_RATE_MASK | AXP813_V_I_ADC_RATE_MASK)
@@ -70,6 +82,25 @@ struct axp20x_adc_iio {
 	const struct axp_data	*data;
 };
 
+enum axp192_adc_channel_v {
+	AXP192_ACIN_V = 0,
+	AXP192_VBUS_V,
+	AXP192_TS_IN,
+	AXP192_GPIO0_V,
+	AXP192_GPIO1_V,
+	AXP192_GPIO2_V,
+	AXP192_GPIO3_V,
+	AXP192_IPSOUT_V,
+	AXP192_BATT_V,
+};
+
+enum axp192_adc_channel_i {
+	AXP192_ACIN_I = 0,
+	AXP192_VBUS_I,
+	AXP192_BATT_CHRG_I,
+	AXP192_BATT_DISCHRG_I,
+};
+
 enum axp20x_adc_channel_v {
 	AXP20X_ACIN_V = 0,
 	AXP20X_VBUS_V,
@@ -157,6 +188,43 @@ static struct iio_map axp22x_maps[] = {
  * The only exception is for the battery. batt_v will be in_voltage6_raw and
  * charge current in_current6_raw and discharge current will be in_current7_raw.
  */
+static const struct iio_chan_spec axp192_adc_channels[] = {
+	AXP20X_ADC_CHANNEL(AXP192_ACIN_V, "acin_v", IIO_VOLTAGE,
+			   AXP20X_ACIN_V_ADC_H),
+	AXP20X_ADC_CHANNEL(AXP192_ACIN_I, "acin_i", IIO_CURRENT,
+			   AXP20X_ACIN_I_ADC_H),
+	AXP20X_ADC_CHANNEL(AXP192_VBUS_V, "vbus_v", IIO_VOLTAGE,
+			   AXP20X_VBUS_V_ADC_H),
+	AXP20X_ADC_CHANNEL(AXP192_VBUS_I, "vbus_i", IIO_CURRENT,
+			   AXP20X_VBUS_I_ADC_H),
+	{
+		.type = IIO_TEMP,
+		.address = AXP20X_TEMP_ADC_H,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_SCALE) |
+				      BIT(IIO_CHAN_INFO_OFFSET),
+		.datasheet_name = "pmic_temp",
+	},
+	AXP20X_ADC_CHANNEL_OFFSET(AXP192_GPIO0_V, "gpio0_v", IIO_VOLTAGE,
+				  AXP20X_GPIO0_V_ADC_H),
+	AXP20X_ADC_CHANNEL_OFFSET(AXP192_GPIO1_V, "gpio1_v", IIO_VOLTAGE,
+				  AXP20X_GPIO1_V_ADC_H),
+	AXP20X_ADC_CHANNEL_OFFSET(AXP192_GPIO2_V, "gpio2_v", IIO_VOLTAGE,
+				  AXP192_GPIO2_V_ADC_H),
+	AXP20X_ADC_CHANNEL_OFFSET(AXP192_GPIO3_V, "gpio3_v", IIO_VOLTAGE,
+				  AXP192_GPIO3_V_ADC_H),
+	AXP20X_ADC_CHANNEL(AXP192_IPSOUT_V, "ipsout_v", IIO_VOLTAGE,
+			   AXP20X_IPSOUT_V_HIGH_H),
+	AXP20X_ADC_CHANNEL(AXP192_BATT_V, "batt_v", IIO_VOLTAGE,
+			   AXP20X_BATT_V_H),
+	AXP20X_ADC_CHANNEL(AXP192_BATT_CHRG_I, "batt_chrg_i", IIO_CURRENT,
+			   AXP20X_BATT_CHRG_I_H),
+	AXP20X_ADC_CHANNEL(AXP192_BATT_DISCHRG_I, "batt_dischrg_i", IIO_CURRENT,
+			   AXP20X_BATT_DISCHRG_I_H),
+	AXP20X_ADC_CHANNEL(AXP192_TS_IN, "ts_v", IIO_VOLTAGE,
+			   AXP20X_TS_IN_H),
+};
+
 static const struct iio_chan_spec axp20x_adc_channels[] = {
 	AXP20X_ADC_CHANNEL(AXP20X_ACIN_V, "acin_v", IIO_VOLTAGE,
 			   AXP20X_ACIN_V_ADC_H),
@@ -277,6 +345,44 @@ static int axp813_adc_raw(struct iio_dev *indio_dev,
 	return IIO_VAL_INT;
 }
 
+static int axp192_adc_scale_voltage(int channel, int *val, int *val2)
+{
+	switch (channel) {
+	case AXP192_ACIN_V:
+	case AXP192_VBUS_V:
+		*val = 1;
+		*val2 = 700000;
+		return IIO_VAL_INT_PLUS_MICRO;
+
+	case AXP192_GPIO0_V:
+	case AXP192_GPIO1_V:
+	case AXP192_GPIO2_V:
+	case AXP192_GPIO3_V:
+		*val = 0;
+		*val2 = 500000;
+		return IIO_VAL_INT_PLUS_MICRO;
+
+	case AXP192_BATT_V:
+		*val = 1;
+		*val2 = 100000;
+		return IIO_VAL_INT_PLUS_MICRO;
+
+	case AXP192_IPSOUT_V:
+		*val = 1;
+		*val2 = 400000;
+		return IIO_VAL_INT_PLUS_MICRO;
+
+	case AXP192_TS_IN:
+		/* 0.8 mV per LSB */
+		*val = 0;
+		*val2 = 800000;
+		return IIO_VAL_INT_PLUS_MICRO;
+
+	default:
+		return -EINVAL;
+	}
+}
+
 static int axp20x_adc_scale_voltage(int channel, int *val, int *val2)
 {
 	switch (channel) {
@@ -380,6 +486,29 @@ static int axp20x_adc_scale_current(int channel, int *val, int *val2)
 	}
 }
 
+static int axp192_adc_scale(struct iio_chan_spec const *chan, int *val,
+			    int *val2)
+{
+	switch (chan->type) {
+	case IIO_VOLTAGE:
+		return axp192_adc_scale_voltage(chan->channel, val, val2);
+
+	case IIO_CURRENT:
+		/*
+		 * AXP192 current channels are identical to the AXP20x,
+		 * therefore we can re-use the scaling function.
+		 */
+		return axp20x_adc_scale_current(chan->channel, val, val2);
+
+	case IIO_TEMP:
+		*val = 100;
+		return IIO_VAL_INT;
+
+	default:
+		return -EINVAL;
+	}
+}
+
 static int axp20x_adc_scale(struct iio_chan_spec const *chan, int *val,
 			    int *val2)
 {
@@ -439,6 +568,42 @@ static int axp813_adc_scale(struct iio_chan_spec const *chan, int *val,
 	}
 }
 
+static int axp192_adc_offset_voltage(struct iio_dev *indio_dev, int channel,
+				     int *val)
+{
+	struct axp20x_adc_iio *info = iio_priv(indio_dev);
+	int ret;
+
+	ret = regmap_read(info->regmap, AXP192_GPIO30_IN_RANGE, val);
+	if (ret < 0)
+		return ret;
+
+	switch (channel) {
+	case AXP192_GPIO0_V:
+		*val &= AXP192_GPIO30_IN_RANGE_GPIO0;
+		break;
+
+	case AXP192_GPIO1_V:
+		*val &= AXP192_GPIO30_IN_RANGE_GPIO1;
+		break;
+
+	case AXP192_GPIO2_V:
+		*val &= AXP192_GPIO30_IN_RANGE_GPIO2;
+		break;
+
+	case AXP192_GPIO3_V:
+		*val &= AXP192_GPIO30_IN_RANGE_GPIO3;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	*val = *val ? 700000 : 0;
+
+	return IIO_VAL_INT;
+}
+
 static int axp20x_adc_offset_voltage(struct iio_dev *indio_dev, int channel,
 				     int *val)
 {
@@ -467,6 +632,22 @@ static int axp20x_adc_offset_voltage(struct iio_dev *indio_dev, int channel,
 	return IIO_VAL_INT;
 }
 
+static int axp192_adc_offset(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan, int *val)
+{
+	switch (chan->type) {
+	case IIO_VOLTAGE:
+		return axp192_adc_offset_voltage(indio_dev, chan->channel, val);
+
+	case IIO_TEMP:
+		*val = -1447;
+		return IIO_VAL_INT;
+
+	default:
+		return -EINVAL;
+	}
+}
+
 static int axp20x_adc_offset(struct iio_dev *indio_dev,
 			     struct iio_chan_spec const *chan, int *val)
 {
@@ -483,6 +664,25 @@ static int axp20x_adc_offset(struct iio_dev *indio_dev,
 	}
 }
 
+static int axp192_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan, int *val,
+			   int *val2, long mask)
+{
+	switch (mask) {
+	case IIO_CHAN_INFO_OFFSET:
+		return axp192_adc_offset(indio_dev, chan, val);
+
+	case IIO_CHAN_INFO_SCALE:
+		return axp192_adc_scale(chan, val, val2);
+
+	case IIO_CHAN_INFO_RAW:
+		return axp20x_adc_raw(indio_dev, chan, val);
+
+	default:
+		return -EINVAL;
+	}
+}
+
 static int axp20x_read_raw(struct iio_dev *indio_dev,
 			   struct iio_chan_spec const *chan, int *val,
 			   int *val2, long mask)
@@ -543,6 +743,54 @@ static int axp813_read_raw(struct iio_dev *indio_dev,
 	}
 }
 
+static int axp192_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan, int val, int val2,
+			    long mask)
+{
+	struct axp20x_adc_iio *info = iio_priv(indio_dev);
+	unsigned int reg, regval;
+
+	/*
+	 * The AXP192 PMIC allows the user to choose between 0V and 0.7V offsets
+	 * for (independently) GPIO0-3 when in ADC mode.
+	 */
+	if (mask != IIO_CHAN_INFO_OFFSET)
+		return -EINVAL;
+
+	if (val != 0 && val != 700000)
+		return -EINVAL;
+
+	val = val ? 1 : 0;
+
+	switch (chan->channel) {
+	case AXP192_GPIO0_V:
+		reg = AXP192_GPIO30_IN_RANGE_GPIO0;
+		regval = AXP192_GPIO30_IN_RANGE_GPIO0_VAL(val);
+		break;
+
+	case AXP192_GPIO1_V:
+		reg = AXP192_GPIO30_IN_RANGE_GPIO1;
+		regval = AXP192_GPIO30_IN_RANGE_GPIO1_VAL(val);
+		break;
+
+	case AXP192_GPIO2_V:
+		reg = AXP192_GPIO30_IN_RANGE_GPIO2;
+		regval = AXP192_GPIO30_IN_RANGE_GPIO2_VAL(val);
+		break;
+
+	case AXP192_GPIO3_V:
+		reg = AXP192_GPIO30_IN_RANGE_GPIO3;
+		regval = AXP192_GPIO30_IN_RANGE_GPIO3_VAL(val);
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return regmap_update_bits(info->regmap, AXP192_GPIO30_IN_RANGE, reg,
+				  regval);
+}
+
 static int axp20x_write_raw(struct iio_dev *indio_dev,
 			    struct iio_chan_spec const *chan, int val, int val2,
 			    long mask)
@@ -581,6 +829,18 @@ static int axp20x_write_raw(struct iio_dev *indio_dev,
 				  regval);
 }
 
+static int axp192_read_label(struct iio_dev *iio_dev,
+			     const struct iio_chan_spec *chan, char *label)
+{
+	return snprintf(label, PAGE_SIZE, "%s\n", chan->datasheet_name);
+}
+
+static const struct iio_info axp192_adc_iio_info = {
+	.read_raw = axp192_read_raw,
+	.write_raw = axp192_write_raw,
+	.read_label = axp192_read_label,
+};
+
 static const struct iio_info axp20x_adc_iio_info = {
 	.read_raw = axp20x_read_raw,
 	.write_raw = axp20x_write_raw,
@@ -620,19 +880,29 @@ struct axp_data {
 	int				num_channels;
 	struct iio_chan_spec const	*channels;
 	unsigned long			adc_en1_mask;
+	unsigned long			adc_en2_mask;
 	int				(*adc_rate)(struct axp20x_adc_iio *info,
 						    int rate);
-	bool				adc_en2;
 	struct iio_map			*maps;
 };
 
+static const struct axp_data axp192_data = {
+	.iio_info = &axp192_adc_iio_info,
+	.num_channels = ARRAY_SIZE(axp192_adc_channels),
+	.channels = axp192_adc_channels,
+	.adc_en1_mask = AXP192_ADC_EN1_MASK,
+	.adc_en2_mask = AXP192_ADC_EN2_MASK,
+	.adc_rate = axp20x_adc_rate,
+	.maps = axp20x_maps,
+};
+
 static const struct axp_data axp20x_data = {
 	.iio_info = &axp20x_adc_iio_info,
 	.num_channels = ARRAY_SIZE(axp20x_adc_channels),
 	.channels = axp20x_adc_channels,
 	.adc_en1_mask = AXP20X_ADC_EN1_MASK,
+	.adc_en2_mask = AXP20X_ADC_EN2_MASK,
 	.adc_rate = axp20x_adc_rate,
-	.adc_en2 = true,
 	.maps = axp20x_maps,
 };
 
@@ -642,7 +912,6 @@ static const struct axp_data axp22x_data = {
 	.channels = axp22x_adc_channels,
 	.adc_en1_mask = AXP22X_ADC_EN1_MASK,
 	.adc_rate = axp22x_adc_rate,
-	.adc_en2 = false,
 	.maps = axp22x_maps,
 };
 
@@ -652,11 +921,11 @@ static const struct axp_data axp813_data = {
 	.channels = axp813_adc_channels,
 	.adc_en1_mask = AXP22X_ADC_EN1_MASK,
 	.adc_rate = axp813_adc_rate,
-	.adc_en2 = false,
 	.maps = axp22x_maps,
 };
 
 static const struct of_device_id axp20x_adc_of_match[] = {
+	{ .compatible = "x-powers,axp192-adc", .data = (void *)&axp192_data, },
 	{ .compatible = "x-powers,axp209-adc", .data = (void *)&axp20x_data, },
 	{ .compatible = "x-powers,axp221-adc", .data = (void *)&axp22x_data, },
 	{ .compatible = "x-powers,axp813-adc", .data = (void *)&axp813_data, },
@@ -665,6 +934,7 @@ static const struct of_device_id axp20x_adc_of_match[] = {
 MODULE_DEVICE_TABLE(of, axp20x_adc_of_match);
 
 static const struct platform_device_id axp20x_adc_id_match[] = {
+	{ .name = "axp192-adc", .driver_data = (kernel_ulong_t)&axp192_data, },
 	{ .name = "axp20x-adc", .driver_data = (kernel_ulong_t)&axp20x_data, },
 	{ .name = "axp22x-adc", .driver_data = (kernel_ulong_t)&axp22x_data, },
 	{ .name = "axp813-adc", .driver_data = (kernel_ulong_t)&axp813_data, },
@@ -710,10 +980,11 @@ static int axp20x_probe(struct platform_device *pdev)
 	/* Enable the ADCs on IP */
 	regmap_write(info->regmap, AXP20X_ADC_EN1, info->data->adc_en1_mask);
 
-	if (info->data->adc_en2)
-		/* Enable GPIO0/1 and internal temperature ADCs */
+	if (info->data->adc_en2_mask)
+		/* Enable GPIO and internal temperature ADCs */
 		regmap_update_bits(info->regmap, AXP20X_ADC_EN2,
-				   AXP20X_ADC_EN2_MASK, AXP20X_ADC_EN2_MASK);
+				   info->data->adc_en2_mask,
+				   info->data->adc_en2_mask);
 
 	/* Configure ADCs rate */
 	info->data->adc_rate(info, 100);
@@ -738,7 +1009,7 @@ static int axp20x_probe(struct platform_device *pdev)
 fail_map:
 	regmap_write(info->regmap, AXP20X_ADC_EN1, 0);
 
-	if (info->data->adc_en2)
+	if (info->data->adc_en2_mask)
 		regmap_write(info->regmap, AXP20X_ADC_EN2, 0);
 
 	return ret;
@@ -754,7 +1025,7 @@ static int axp20x_remove(struct platform_device *pdev)
 
 	regmap_write(info->regmap, AXP20X_ADC_EN1, 0);
 
-	if (info->data->adc_en2)
+	if (info->data->adc_en2_mask)
 		regmap_write(info->regmap, AXP20X_ADC_EN2, 0);
 
 	return 0;
-- 
2.35.1


  parent reply	other threads:[~2022-06-03 13:57 UTC|newest]

Thread overview: 36+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-06-03 13:57 [PATCH 00/10] Add support for AXP192 PMIC Aidan MacDonald
2022-06-03 13:57 ` [PATCH 01/10] regmap-irq: Add get_irq_reg to support unusual register layouts Aidan MacDonald
2022-06-06 17:43   ` Guru Das Srinagesh
2022-06-07 10:46     ` Aidan MacDonald
2022-06-03 13:57 ` [PATCH 02/10] dt-bindings: mfd: add bindings for AXP192 MFD device Aidan MacDonald
2022-06-05 22:49   ` Rob Herring
2022-06-27 11:47   ` Lee Jones
2022-06-03 13:57 ` [PATCH 03/10] dt-bindings: iio: adc: axp209: Add AXP192 compatible Aidan MacDonald
2022-06-03 16:34   ` Jonathan Cameron
2022-06-04 11:33     ` Aidan MacDonald
2022-06-05 22:50   ` Rob Herring
2022-06-03 13:57 ` [PATCH 04/10] dt-bindings: power: supply: axp20x: " Aidan MacDonald
2022-06-05 22:50   ` Rob Herring
2022-06-03 13:57 ` [PATCH 05/10] dt-bindings: gpio: Add AXP192 GPIO bindings Aidan MacDonald
2022-06-05 22:55   ` Rob Herring
2022-06-07 10:34     ` Aidan MacDonald
2022-06-07 15:17       ` Rob Herring
2022-06-07 15:40         ` Aidan MacDonald
2022-06-03 13:57 ` [PATCH 06/10] mfd: axp20x: Add support for AXP192 Aidan MacDonald
2022-06-27 11:54   ` Lee Jones
2022-06-27 13:02     ` Aidan MacDonald
2022-06-03 13:57 ` [PATCH 07/10] regulator: " Aidan MacDonald
2022-06-06 14:36   ` Mark Brown
2022-06-03 13:57 ` Aidan MacDonald [this message]
2022-06-03 16:47   ` [PATCH 08/10] iio: adc: axp20x_adc: " Jonathan Cameron
2022-06-04 11:47     ` Aidan MacDonald
2022-06-04 14:27       ` Jonathan Cameron
2022-06-07 10:49         ` Aidan MacDonald
2022-06-03 13:57 ` [PATCH 09/10] power: supply: axp20x_usb_power: " Aidan MacDonald
2022-06-05 15:13   ` kernel test robot
2022-06-03 13:57 ` [PATCH 10/10] pinctrl: Add AXP192 pin control driver Aidan MacDonald
2022-06-15 13:44   ` Linus Walleij
2022-06-15 18:06     ` Michael Walle
2022-06-15 14:51   ` Andy Shevchenko
2022-06-17 12:15     ` Aidan MacDonald
2022-06-17 16:08       ` Andy Shevchenko

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