This patch add an ADC IP found on EXYNOS5 series socs from Samsung.
Also adds the Documentation for device tree bindings.
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@xxxxxxxxxxx>
---
.../bindings/arm/samsung/exynos5-adc.txt | 20 +
drivers/iio/adc/Kconfig | 7 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/exynos5_adc.c | 412 ++++++++++++++++++++
4 files changed, 440 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/samsung/exynos5-adc.txt
create mode 100644 drivers/iio/adc/exynos5_adc.c
diff --git a/Documentation/devicetree/bindings/arm/samsung/exynos5-adc.txt b/Documentation/devicetree/bindings/arm/samsung/exynos5-adc.txt
new file mode 100644
index 0000000..069639e
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/samsung/exynos5-adc.txt
@@ -0,0 +1,20 @@
+Samsung Exynos5 Analog to Digital Converter bindings
+
+Required properties:
+- compatible: Must be "samsung,exynos5250-adc" for exynos5250 controllers.
+- reg: Contains ADC register address range (base address and
+ length).
+- interrupts: Contains the interrupt information for the timer. The
+ format is being dependent on which interrupt controller
+ the Samsung device uses.
+
+Example:
+
+adc@12D10000 {
+ compatible = "samsung,exynos5250-adc";
+ reg = <0x12D10000 0x100>;
+ interrupts = <0 106 0>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+};
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index fe822a1..33ceabf 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -91,6 +91,13 @@ config AT91_ADC
help
Say yes here to build support for Atmel AT91 ADC.
+config EXYNOS5_ADC
+ bool "Exynos5 ADC driver support"
+ help
+ Core support for the ADC block found in the Samsung EXYNOS5 series
+ of SoCs for drivers such as the touchscreen and hwmon to use to share
+ this resource.
+
config LP8788_ADC
bool "LP8788 ADC driver"
depends on MFD_LP8788
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 2d5f100..5b4a4f6 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_AD7791) += ad7791.o
obj-$(CONFIG_AD7793) += ad7793.o
obj-$(CONFIG_AD7887) += ad7887.o
obj-$(CONFIG_AT91_ADC) += at91_adc.o
+obj-$(CONFIG_EXYNOS5_ADC) += exynos5_adc.o
obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
obj-$(CONFIG_MAX1363) += max1363.o
obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
diff --git a/drivers/iio/adc/exynos5_adc.c b/drivers/iio/adc/exynos5_adc.c
new file mode 100644
index 0000000..cd33ea2
--- /dev/null
+++ b/drivers/iio/adc/exynos5_adc.c
@@ -0,0 +1,412 @@
+/*
+ * exynos5_adc.c - Support for ADC in EXYNOS5 SoCs
+ *
+ * 8-channel, 10/12-bit ADC
+ *
+ * Copyright (C) 2013 Naveen Krishna Chatradhi <ch.naveen@xxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/regulator/consumer.h>
+#include <linux/of_platform.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/machine.h>
+#include <linux/iio/driver.h>
+
+/* Samsung ADC registers definitions */
+#define EXYNOS_ADC_CON(x) ((x) + 0x00)
+#define EXYNOS_ADC_DLY(x) ((x) + 0x08)
+#define EXYNOS_ADC_DATX(x) ((x) + 0x0C)
+#define EXYNOS_ADC_INTCLR(x) ((x) + 0x18)
+#define EXYNOS_ADC_MUX(x) ((x) + 0x1c)
+
+/* Bit definitions for EXYNOS_ADC_MUX: */
+#define ADC_RES (1u << 16)
+#define ADC_ECFLG (1u << 15)
+#define ADC_PRSCEN (1u << 14)
+#define ADC_PRSCLV(x) (((x) & 0xFF) << 6)
+#define ADC_PRSCVLMASK (0xFF << 6)
+#define ADC_STANDBY (1u << 2)
+#define ADC_READ_START (1u << 1)
+#define ADC_EN_START (1u << 0)
+
+#define ADC_DATX_MASK 0xFFF
+
+struct exynos5_adc {
+ void __iomem *regs;
+ struct clk *clk;
+ unsigned int irq;
+ struct regulator *vdd;
+
+ struct completion completion;
+
+ struct iio_map *map;
+ u32 value;
+ u32 prescale;
+};
+
+static const struct of_device_id exynos5_adc_match[] = {
+ { .compatible = "samsung,exynos5250-adc" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, exynos5_adc_match);
+
+/* default maps used by iio consumer (ex: ntc-thermistor driver) */
+static struct iio_map exynos5_adc_iio_maps[] = {
+ {
+ .consumer_dev_name = "0.ncp15wb473",
+ .consumer_channel = "adc_user3",
+ .adc_channel_label = "adc3",
+ },
+ {},
+};
+
+static int exynos5_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long mask)
+{
+ struct exynos5_adc *info = iio_priv(indio_dev);
+ u32 con;
+
+ if (mask == IIO_CHAN_INFO_RAW) {
+ mutex_lock(&indio_dev->mlock);
+
+ /* Select the channel to be used */
+ writel(chan->address, EXYNOS_ADC_MUX(info->regs));
+ /* Trigger conversion */
+ con = readl(EXYNOS_ADC_CON(info->regs));
+ writel(con | ADC_EN_START, EXYNOS_ADC_CON(info->regs));
+
+ wait_for_completion(&info->completion);
+ *val = info->value;
+
+ mutex_unlock(&indio_dev->mlock);
+
+ return IIO_VAL_INT;
+ }
+
+ return -EINVAL;
+}
+
+static irqreturn_t exynos5_adc_isr(int irq, void *dev_id)
+{
+ struct exynos5_adc *info = (struct exynos5_adc *)dev_id;
+
+ /* Read value and clear irq */
+ info->value = readl(EXYNOS_ADC_DATX(info->regs)) &
+ ADC_DATX_MASK;
+ writel(0, EXYNOS_ADC_INTCLR(info->regs));
+
+ complete(&info->completion);
+
+ return IRQ_HANDLED;
+}
+
+static int exynos5_adc_reg_access(struct iio_dev *indio_dev,
+ unsigned reg, unsigned writeval,
+ unsigned *readval)
+{
+ struct exynos5_adc *info = iio_priv(indio_dev);
+ u32 ret;
+
+ mutex_lock(&indio_dev->mlock);
+
+ if (readval != NULL) {
+ if (reg == 0x08)
+ ret = readl(EXYNOS_ADC_DLY(info->regs));
+ else if (reg == 0x0C)
+ ret = readl(EXYNOS_ADC_DATX(info->regs));
+ else if (reg == 0x1C)
+ ret = readl(EXYNOS_ADC_MUX(info->regs));
+ else
+ ret = readl(EXYNOS_ADC_CON(info->regs));
+
+ readval = &ret;
+ } else
+ ret = -EINVAL;
+
+ mutex_unlock(&indio_dev->mlock);
+
+ return ret;
+}
+
+static const struct iio_info exynos5_adc_iio_info = {
+ .read_raw = &exynos5_read_raw,
+ .debugfs_reg_access = &exynos5_adc_reg_access,
+ .driver_module = THIS_MODULE,
+};
+
+#define EXYNOS_ADC_CHANNEL(_index, _id) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = _index, \
+ .address = _index, \
+ .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT, \
+ .datasheet_name = _id, \
+}
+
+static const struct iio_chan_spec exynos5_adc_iio_channels[] = {
+ EXYNOS_ADC_CHANNEL(0, "adc0"),
+ EXYNOS_ADC_CHANNEL(1, "adc1"),
+ EXYNOS_ADC_CHANNEL(2, "adc2"),
+ EXYNOS_ADC_CHANNEL(3, "adc3"),
+ EXYNOS_ADC_CHANNEL(4, "adc4"),
+ EXYNOS_ADC_CHANNEL(5, "adc5"),
+ EXYNOS_ADC_CHANNEL(6, "adc6"),
+ EXYNOS_ADC_CHANNEL(7, "adc7"),
+};
+
+static int exynos5_adc_iio_map_register(struct iio_dev *indio_dev,
+ struct exynos5_adc *adc)
+{
+ int ret;
+
+ adc->map = exynos5_adc_iio_maps;
+
+ ret = iio_map_array_register(indio_dev, adc->map);
+ if (ret) {
+ dev_err(&indio_dev->dev, "iio map err: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static inline void exynos5_adc_iio_map_unregister(struct iio_dev *indio_dev,
+ struct exynos5_adc *adc)
+{
+ iio_map_array_unregister(indio_dev, adc->map);
+}
+
+static int exynos5_adc_remove_devices(struct device *dev, void *c)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+
+ platform_device_unregister(pdev);
+
+ return 0;
+}
+
+static int exynos5_adc_probe(struct platform_device *pdev)
+{
+ struct exynos5_adc *info = NULL;
+ struct device_node *np = pdev->dev.of_node;
+ struct iio_dev *iodev = NULL;
+ struct resource *mem;
+ int ret = -ENODEV;
+ int irq;
+ u32 con;
+
+ iodev = iio_device_alloc(sizeof(struct exynos5_adc));
+ if (!iodev) {
+ dev_err(&pdev->dev, "failed allocating iio device\n");
+ return -ENOMEM;
+ }
+
+ info = iio_priv(iodev);
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!mem) {
+ dev_err(&pdev->dev, "no mem resource?\n");
+ goto err_iio;
+ }
+
+ info->regs = devm_request_and_ioremap(&pdev->dev, mem);
+ if (!info->regs) {
+ dev_err(&pdev->dev, "cannot map EXYNOS5 ADC registers\n");
+ ret = -ENOMEM;
+ goto err_iio;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "no irq resource?\n");
+ ret = irq;
+ goto err_iio;
+ }
+
+ info->irq = irq;
+
+ ret = devm_request_irq(&pdev->dev, info->irq, exynos5_adc_isr,
+ 0, dev_name(&pdev->dev), info);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "cannot request Samsung ADC IRQ %d\n",
+ info->irq);
+ goto err_iio;
+ }
+
+ info->clk = devm_clk_get(&pdev->dev, "adc");
+ if (IS_ERR(info->clk)) {
+ dev_err(&pdev->dev, "failed getting clock\n");
+ ret = PTR_ERR(info->clk);
+ goto err_iio;
+ }
+
+ clk_enable(info->clk);
+
+ info->vdd = devm_regulator_get(&pdev->dev, "vdd");
+ if (IS_ERR(info->vdd)) {
+ dev_err(&pdev->dev, "operating without regulator \"vdd\" .\n");
+ ret = PTR_ERR(info->vdd);
+ goto err_iio;
+ }
+
+ platform_set_drvdata(pdev, iodev);
+
+ init_completion(&info->completion);
+
+ iodev->name = dev_name(&pdev->dev);
+ iodev->dev.parent = &pdev->dev;
+ iodev->dev.of_node = pdev->dev.of_node;
+ iodev->info = &exynos5_adc_iio_info;
+ iodev->modes = INDIO_DIRECT_MODE;
+ iodev->channels = exynos5_adc_iio_channels;
+ iodev->num_channels = ARRAY_SIZE(exynos5_adc_iio_channels);
+
+ /* Enable prescaler and set platform default */
+ info->prescale = ADC_PRSCLV(49);
+ con = info->prescale | ADC_PRSCEN;
+
+ /* Enable 12-bit ADC resolution */
+ con |= ADC_RES;
+
+ writel(con, EXYNOS_ADC_CON(info->regs));
+
+ ret = exynos5_adc_iio_map_register(iodev, info);
+ if (ret)
+ goto err_iio;
+
+ ret = iio_device_register(iodev);
+ if (ret)
+ goto err_map;
+
+ ret = regulator_enable(info->vdd);
+ if (ret)
+ goto err_iio_dev;
+
+ ret = of_platform_populate(np, exynos5_adc_match, NULL, &pdev->dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to add child nodes\n");
+ goto err_of_populate;
+ }
+
+ dev_info(&pdev->dev, "EXYNOS5 ADC driver loaded.\n");
+
+ return 0;
+
+err_of_populate:
+ device_for_each_child(&pdev->dev, NULL, exynos5_adc_remove_devices);
+err_iio_dev:
+ iio_device_unregister(iodev);
+err_map:
+ exynos5_adc_iio_map_unregister(iodev, info);
+err_iio:
+ iio_device_free(iodev);
+ return ret;
+}
+
+static int exynos5_adc_remove(struct platform_device *pdev)
+{
+ struct iio_dev *iodev = platform_get_drvdata(pdev);
+ struct exynos5_adc *info = iio_priv(iodev);
+
+ platform_set_drvdata(pdev, NULL);
+ iio_device_unregister(iodev);
+ exynos5_adc_iio_map_unregister(iodev, info);
+ iio_device_free(iodev);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int exynos5_adc_suspend(struct device *dev)
+{
+ struct platform_device *pdev = container_of(dev,
+ struct platform_device, dev);
+ struct exynos5_adc *info = platform_get_drvdata(pdev);
+ u32 con;
+
+ con = readl(EXYNOS_ADC_CON(info->regs));
+ con |= ADC_STANDBY;
+ writel(con, EXYNOS_ADC_CON(info->regs));
+
+ clk_disable(info->clk);
+ regulator_disable(info->vdd);
+
+ return 0;
+}
+
+static int exynos5_adc_resume(struct device *dev)
+{
+ struct platform_device *pdev = container_of(dev,
+ struct platform_device, dev);
+ struct exynos5_adc *info = platform_get_drvdata(pdev);
+ unsigned int con;
+ int ret;
+
+ ret = regulator_enable(info->vdd);
+ if (ret)
+ return ret;
+
+ clk_enable(info->clk);
+
+ /* TODO: Enable prescalar */
+ con = info->prescale | ADC_PRSCEN;
+ writel(con | ADC_RES, EXYNOS_ADC_CON(info->regs));
+
+ return 0;
+}
+
+#else
+#define s3c_adc_suspend NULL
+#define s3c_adc_resume NULL
+#endif
+
+static const struct dev_pm_ops adc_pm_ops = {
+ .suspend = exynos5_adc_suspend,
+ .resume = exynos5_adc_resume,
+};
+
+static struct platform_driver exynos5_adc_driver = {
+ .probe = exynos5_adc_probe,
+ .remove = exynos5_adc_remove,
+ .driver = {
+ .name = "exynos5-adc",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(exynos5_adc_match),
+ .pm = &adc_pm_ops,
+ },
+};
+
+module_platform_driver(exynos5_adc_driver);
+
+MODULE_AUTHOR("Naveen Krishna Chatradhi <ch.naveen@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("Samsung EXYNOS5 ADC driver");
+MODULE_LICENSE("GPL");
--
1.7.9.5
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