--- /dev/null
+/*
+ * 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");
projects / platform / kernel / linux-starfive.git / commitdiff