Linux-libre 4.2-gnu

1 files changed, 378 insertions, 0 deletions

diff --git a/drivers/iio/adc/berlin2-adc.c b/drivers/iio/adc/berlin2-adc.c
new file mode 100644
index 000000000..aecc9ad99
--- /dev/null
+++ b/drivers/iio/adc/berlin2-adc.c
@@ -0,0 +1,378 @@
+/*
+ * Marvell Berlin2 ADC driver
+ *
+ * Copyright (C) 2015 Marvell Technology Group Ltd.
+ *
+ * Antoine Tenart <antoine.tenart@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/iio/iio.h>
+#include <linux/iio/driver.h>
+#include <linux/iio/machine.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+
+#define BERLIN2_SM_CTRL				0x14
+#define  BERLIN2_SM_CTRL_SM_SOC_INT		BIT(1)
+#define  BERLIN2_SM_CTRL_SOC_SM_INT		BIT(2)
+#define  BERLIN2_SM_CTRL_ADC_SEL(x)		(BIT(x) << 5)	/* 0-15 */
+#define  BERLIN2_SM_CTRL_ADC_SEL_MASK		(0xf << 5)
+#define  BERLIN2_SM_CTRL_ADC_POWER		BIT(9)
+#define  BERLIN2_SM_CTRL_ADC_CLKSEL_DIV2	(0x0 << 10)
+#define  BERLIN2_SM_CTRL_ADC_CLKSEL_DIV3	(0x1 << 10)
+#define  BERLIN2_SM_CTRL_ADC_CLKSEL_DIV4	(0x2 << 10)
+#define  BERLIN2_SM_CTRL_ADC_CLKSEL_DIV8	(0x3 << 10)
+#define  BERLIN2_SM_CTRL_ADC_CLKSEL_MASK	(0x3 << 10)
+#define  BERLIN2_SM_CTRL_ADC_START		BIT(12)
+#define  BERLIN2_SM_CTRL_ADC_RESET		BIT(13)
+#define  BERLIN2_SM_CTRL_ADC_BANDGAP_RDY	BIT(14)
+#define  BERLIN2_SM_CTRL_ADC_CONT_SINGLE	(0x0 << 15)
+#define  BERLIN2_SM_CTRL_ADC_CONT_CONTINUOUS	(0x1 << 15)
+#define  BERLIN2_SM_CTRL_ADC_BUFFER_EN		BIT(16)
+#define  BERLIN2_SM_CTRL_ADC_VREF_EXT		(0x0 << 17)
+#define  BERLIN2_SM_CTRL_ADC_VREF_INT		(0x1 << 17)
+#define  BERLIN2_SM_CTRL_ADC_ROTATE		BIT(19)
+#define  BERLIN2_SM_CTRL_TSEN_EN		BIT(20)
+#define  BERLIN2_SM_CTRL_TSEN_CLK_SEL_125	(0x0 << 21)	/* 1.25 MHz */
+#define  BERLIN2_SM_CTRL_TSEN_CLK_SEL_250	(0x1 << 21)	/* 2.5 MHz */
+#define  BERLIN2_SM_CTRL_TSEN_MODE_0_125	(0x0 << 22)	/* 0-125 C */
+#define  BERLIN2_SM_CTRL_TSEN_MODE_10_50	(0x1 << 22)	/* 10-50 C */
+#define  BERLIN2_SM_CTRL_TSEN_RESET		BIT(29)
+#define BERLIN2_SM_ADC_DATA			0x20
+#define  BERLIN2_SM_ADC_MASK			0x3ff
+#define BERLIN2_SM_ADC_STATUS			0x1c
+#define  BERLIN2_SM_ADC_STATUS_DATA_RDY(x)	BIT(x)		/* 0-15 */
+#define  BERLIN2_SM_ADC_STATUS_DATA_RDY_MASK	0xf
+#define  BERLIN2_SM_ADC_STATUS_INT_EN(x)	(BIT(x) << 16)	/* 0-15 */
+#define  BERLIN2_SM_ADC_STATUS_INT_EN_MASK	(0xf << 16)
+#define BERLIN2_SM_TSEN_STATUS			0x24
+#define  BERLIN2_SM_TSEN_STATUS_DATA_RDY	BIT(0)
+#define  BERLIN2_SM_TSEN_STATUS_INT_EN		BIT(1)
+#define BERLIN2_SM_TSEN_DATA			0x28
+#define  BERLIN2_SM_TSEN_MASK			0xfff
+#define BERLIN2_SM_TSEN_CTRL			0x74
+#define  BERLIN2_SM_TSEN_CTRL_START		BIT(8)
+#define  BERLIN2_SM_TSEN_CTRL_SETTLING_4	(0x0 << 21)	/* 4 us */
+#define  BERLIN2_SM_TSEN_CTRL_SETTLING_12	(0x1 << 21)	/* 12 us */
+#define  BERLIN2_SM_TSEN_CTRL_SETTLING_MASK	(0x1 << 21)
+#define  BERLIN2_SM_TSEN_CTRL_TRIM(x)		((x) << 22)
+#define  BERLIN2_SM_TSEN_CTRL_TRIM_MASK		(0xf << 22)
+
+struct berlin2_adc_priv {
+	struct regmap		*regmap;
+	struct mutex		lock;
+	wait_queue_head_t	wq;
+	bool			data_available;
+	int			data;
+};
+
+#define BERLIN2_ADC_CHANNEL(n, t)					\
+		{							\
+			.channel	= n,				\
+			.datasheet_name	= "channel"#n,			\
+			.type		= t,				\
+			.indexed	= 1,				\
+			.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
+		}
+
+static struct iio_chan_spec berlin2_adc_channels[] = {
+	BERLIN2_ADC_CHANNEL(0, IIO_VOLTAGE),	/* external input */
+	BERLIN2_ADC_CHANNEL(1, IIO_VOLTAGE),	/* external input */
+	BERLIN2_ADC_CHANNEL(2, IIO_VOLTAGE),	/* external input */
+	BERLIN2_ADC_CHANNEL(3, IIO_VOLTAGE),	/* external input */
+	BERLIN2_ADC_CHANNEL(4, IIO_VOLTAGE),	/* reserved */
+	BERLIN2_ADC_CHANNEL(5, IIO_VOLTAGE),	/* reserved */
+	{					/* temperature sensor */
+		.channel		= 6,
+		.datasheet_name		= "channel6",
+		.type			= IIO_TEMP,
+		.indexed		= 0,
+		.info_mask_separate	= BIT(IIO_CHAN_INFO_PROCESSED),
+	},
+	BERLIN2_ADC_CHANNEL(7, IIO_VOLTAGE),	/* reserved */
+	IIO_CHAN_SOFT_TIMESTAMP(8),		/* timestamp */
+};
+#define BERLIN2_N_CHANNELS	ARRAY_SIZE(berlin2_adc_channels)
+
+static int berlin2_adc_read(struct iio_dev *indio_dev, int channel)
+{
+	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
+	int data, ret;
+
+	mutex_lock(&priv->lock);
+
+	/* Configure the ADC */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
+			BERLIN2_SM_CTRL_ADC_RESET | BERLIN2_SM_CTRL_ADC_SEL_MASK
+			| BERLIN2_SM_CTRL_ADC_START,
+			BERLIN2_SM_CTRL_ADC_SEL(channel) | BERLIN2_SM_CTRL_ADC_START);
+
+	ret = wait_event_interruptible_timeout(priv->wq, priv->data_available,
+			msecs_to_jiffies(1000));
+
+	/* Disable the interrupts */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_ADC_STATUS,
+			BERLIN2_SM_ADC_STATUS_INT_EN(channel), 0);
+
+	if (ret == 0)
+		ret = -ETIMEDOUT;
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
+
+	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
+			BERLIN2_SM_CTRL_ADC_START, 0);
+
+	data = priv->data;
+	priv->data_available = false;
+
+	mutex_unlock(&priv->lock);
+
+	return data;
+}
+
+static int berlin2_adc_tsen_read(struct iio_dev *indio_dev)
+{
+	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
+	int data, ret;
+
+	mutex_lock(&priv->lock);
+
+	/* Configure the ADC */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
+			BERLIN2_SM_CTRL_TSEN_RESET | BERLIN2_SM_CTRL_ADC_ROTATE,
+			BERLIN2_SM_CTRL_ADC_ROTATE);
+
+	/* Configure the temperature sensor */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_TSEN_CTRL,
+			BERLIN2_SM_TSEN_CTRL_TRIM_MASK | BERLIN2_SM_TSEN_CTRL_SETTLING_MASK
+			| BERLIN2_SM_TSEN_CTRL_START,
+			BERLIN2_SM_TSEN_CTRL_TRIM(3) | BERLIN2_SM_TSEN_CTRL_SETTLING_12
+			| BERLIN2_SM_TSEN_CTRL_START);
+
+	ret = wait_event_interruptible_timeout(priv->wq, priv->data_available,
+			msecs_to_jiffies(1000));
+
+	/* Disable interrupts */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_TSEN_STATUS,
+			BERLIN2_SM_TSEN_STATUS_INT_EN, 0);
+
+	if (ret == 0)
+		ret = -ETIMEDOUT;
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
+
+	regmap_update_bits(priv->regmap, BERLIN2_SM_TSEN_CTRL,
+			BERLIN2_SM_TSEN_CTRL_START, 0);
+
+	data = priv->data;
+	priv->data_available = false;
+
+	mutex_unlock(&priv->lock);
+
+	return data;
+}
+
+static int berlin2_adc_read_raw(struct iio_dev *indio_dev,
+		struct iio_chan_spec const *chan, int *val, int *val2,
+		long mask)
+{
+	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
+	int temp;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		if (chan->type != IIO_VOLTAGE)
+			return -EINVAL;
+
+		/* Enable the interrupts */
+		regmap_write(priv->regmap, BERLIN2_SM_ADC_STATUS,
+				BERLIN2_SM_ADC_STATUS_INT_EN(chan->channel));
+
+		*val = berlin2_adc_read(indio_dev, chan->channel);
+		if (*val < 0)
+			return *val;
+
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_PROCESSED:
+		if (chan->type != IIO_TEMP)
+			return -EINVAL;
+
+		/* Enable interrupts */
+		regmap_write(priv->regmap, BERLIN2_SM_TSEN_STATUS,
+				BERLIN2_SM_TSEN_STATUS_INT_EN);
+
+		temp = berlin2_adc_tsen_read(indio_dev);
+		if (temp < 0)
+			return temp;
+
+		if (temp > 2047)
+			temp = -(4096 - temp);
+
+		/* Convert to milli Celsius */
+		*val = ((temp * 100000) / 264 - 270000);
+		return IIO_VAL_INT;
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static irqreturn_t berlin2_adc_irq(int irq, void *private)
+{
+	struct berlin2_adc_priv *priv = iio_priv(private);
+	unsigned val;
+
+	regmap_read(priv->regmap, BERLIN2_SM_ADC_STATUS, &val);
+	if (val & BERLIN2_SM_ADC_STATUS_DATA_RDY_MASK) {
+		regmap_read(priv->regmap, BERLIN2_SM_ADC_DATA, &priv->data);
+		priv->data &= BERLIN2_SM_ADC_MASK;
+
+		val &= ~BERLIN2_SM_ADC_STATUS_DATA_RDY_MASK;
+		regmap_write(priv->regmap, BERLIN2_SM_ADC_STATUS, val);
+
+		priv->data_available = true;
+		wake_up_interruptible(&priv->wq);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t berlin2_adc_tsen_irq(int irq, void *private)
+{
+	struct berlin2_adc_priv *priv = iio_priv(private);
+	unsigned val;
+
+	regmap_read(priv->regmap, BERLIN2_SM_TSEN_STATUS, &val);
+	if (val & BERLIN2_SM_TSEN_STATUS_DATA_RDY) {
+		regmap_read(priv->regmap, BERLIN2_SM_TSEN_DATA, &priv->data);
+		priv->data &= BERLIN2_SM_TSEN_MASK;
+
+		val &= ~BERLIN2_SM_TSEN_STATUS_DATA_RDY;
+		regmap_write(priv->regmap, BERLIN2_SM_TSEN_STATUS, val);
+
+		priv->data_available = true;
+		wake_up_interruptible(&priv->wq);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static const struct iio_info berlin2_adc_info = {
+	.driver_module	= THIS_MODULE,
+	.read_raw	= berlin2_adc_read_raw,
+};
+
+static int berlin2_adc_probe(struct platform_device *pdev)
+{
+	struct iio_dev *indio_dev;
+	struct berlin2_adc_priv *priv;
+	struct device_node *parent_np = of_get_parent(pdev->dev.of_node);
+	int irq, tsen_irq;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&pdev->dev,
+					  sizeof(struct berlin2_adc_priv));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	priv = iio_priv(indio_dev);
+	platform_set_drvdata(pdev, indio_dev);
+
+	priv->regmap = syscon_node_to_regmap(parent_np);
+	of_node_put(parent_np);
+	if (IS_ERR(priv->regmap))
+		return PTR_ERR(priv->regmap);
+
+	irq = platform_get_irq_byname(pdev, "adc");
+	if (irq < 0)
+		return -ENODEV;
+
+	tsen_irq = platform_get_irq_byname(pdev, "tsen");
+	if (tsen_irq < 0)
+		return -ENODEV;
+
+	ret = devm_request_irq(&pdev->dev, irq, berlin2_adc_irq, 0,
+			pdev->dev.driver->name, indio_dev);
+	if (ret)
+		return ret;
+
+	ret = devm_request_irq(&pdev->dev, tsen_irq, berlin2_adc_tsen_irq,
+			0, pdev->dev.driver->name, indio_dev);
+	if (ret)
+		return ret;
+
+	init_waitqueue_head(&priv->wq);
+	mutex_init(&priv->lock);
+
+	indio_dev->dev.parent = &pdev->dev;
+	indio_dev->name = dev_name(&pdev->dev);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->info = &berlin2_adc_info;
+
+	indio_dev->num_channels = BERLIN2_N_CHANNELS;
+	indio_dev->channels = berlin2_adc_channels;
+
+	/* Power up the ADC */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
+			BERLIN2_SM_CTRL_ADC_POWER, BERLIN2_SM_CTRL_ADC_POWER);
+
+	ret = iio_device_register(indio_dev);
+	if (ret) {
+		/* Power down the ADC */
+		regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
+				BERLIN2_SM_CTRL_ADC_POWER, 0);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int berlin2_adc_remove(struct platform_device *pdev)
+{
+	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+
+	/* Power down the ADC */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
+			BERLIN2_SM_CTRL_ADC_POWER, 0);
+
+	return 0;
+}
+
+static const struct of_device_id berlin2_adc_match[] = {
+	{ .compatible = "marvell,berlin2-adc", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, berlin2_adc_match);
+
+static struct platform_driver berlin2_adc_driver = {
+	.driver	= {
+		.name		= "berlin2-adc",
+		.of_match_table	= berlin2_adc_match,
+	},
+	.probe	= berlin2_adc_probe,
+	.remove	= berlin2_adc_remove,
+};
+module_platform_driver(berlin2_adc_driver);
+
+MODULE_AUTHOR("Antoine Tenart <antoine.tenart@free-electrons.com>");
+MODULE_DESCRIPTION("Marvell Berlin2 ADC driver");
+MODULE_LICENSE("GPL v2");