Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 328 insertions, 0 deletions

diff --git a/drivers/iio/adc/mt6577_auxadc.c b/drivers/iio/adc/mt6577_auxadc.c
new file mode 100644
index 000000000..95d76abb6
--- /dev/null
+++ b/drivers/iio/adc/mt6577_auxadc.c
@@ -0,0 +1,328 @@
+/*
+ * Copyright (c) 2016 MediaTek Inc.
+ * Author: Zhiyong Tao <zhiyong.tao@mediatek.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/iopoll.h>
+#include <linux/io.h>
+#include <linux/iio/iio.h>
+
+/* Register definitions */
+#define MT6577_AUXADC_CON0                    0x00
+#define MT6577_AUXADC_CON1                    0x04
+#define MT6577_AUXADC_CON2                    0x10
+#define MT6577_AUXADC_STA                     BIT(0)
+
+#define MT6577_AUXADC_DAT0                    0x14
+#define MT6577_AUXADC_RDY0                    BIT(12)
+
+#define MT6577_AUXADC_MISC                    0x94
+#define MT6577_AUXADC_PDN_EN                  BIT(14)
+
+#define MT6577_AUXADC_DAT_MASK                0xfff
+#define MT6577_AUXADC_SLEEP_US                1000
+#define MT6577_AUXADC_TIMEOUT_US              10000
+#define MT6577_AUXADC_POWER_READY_MS          1
+#define MT6577_AUXADC_SAMPLE_READY_US         25
+
+struct mt6577_auxadc_device {
+	void __iomem *reg_base;
+	struct clk *adc_clk;
+	struct mutex lock;
+};
+
+#define MT6577_AUXADC_CHANNEL(idx) {				    \
+		.type = IIO_VOLTAGE,				    \
+		.indexed = 1,					    \
+		.channel = (idx),				    \
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \
+}
+
+static const struct iio_chan_spec mt6577_auxadc_iio_channels[] = {
+	MT6577_AUXADC_CHANNEL(0),
+	MT6577_AUXADC_CHANNEL(1),
+	MT6577_AUXADC_CHANNEL(2),
+	MT6577_AUXADC_CHANNEL(3),
+	MT6577_AUXADC_CHANNEL(4),
+	MT6577_AUXADC_CHANNEL(5),
+	MT6577_AUXADC_CHANNEL(6),
+	MT6577_AUXADC_CHANNEL(7),
+	MT6577_AUXADC_CHANNEL(8),
+	MT6577_AUXADC_CHANNEL(9),
+	MT6577_AUXADC_CHANNEL(10),
+	MT6577_AUXADC_CHANNEL(11),
+	MT6577_AUXADC_CHANNEL(12),
+	MT6577_AUXADC_CHANNEL(13),
+	MT6577_AUXADC_CHANNEL(14),
+	MT6577_AUXADC_CHANNEL(15),
+};
+
+static inline void mt6577_auxadc_mod_reg(void __iomem *reg,
+					 u32 or_mask, u32 and_mask)
+{
+	u32 val;
+
+	val = readl(reg);
+	val |= or_mask;
+	val &= ~and_mask;
+	writel(val, reg);
+}
+
+static int mt6577_auxadc_read(struct iio_dev *indio_dev,
+			      struct iio_chan_spec const *chan)
+{
+	u32 val;
+	void __iomem *reg_channel;
+	int ret;
+	struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev);
+
+	reg_channel = adc_dev->reg_base + MT6577_AUXADC_DAT0 +
+		      chan->channel * 0x04;
+
+	mutex_lock(&adc_dev->lock);
+
+	mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_CON1,
+			      0, 1 << chan->channel);
+
+	/* read channel and make sure old ready bit == 0 */
+	ret = readl_poll_timeout(reg_channel, val,
+				 ((val & MT6577_AUXADC_RDY0) == 0),
+				 MT6577_AUXADC_SLEEP_US,
+				 MT6577_AUXADC_TIMEOUT_US);
+	if (ret < 0) {
+		dev_err(indio_dev->dev.parent,
+			"wait for channel[%d] ready bit clear time out\n",
+			chan->channel);
+		goto err_timeout;
+	}
+
+	/* set bit to trigger sample */
+	mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_CON1,
+			      1 << chan->channel, 0);
+
+	/* we must delay here for hardware sample channel data */
+	udelay(MT6577_AUXADC_SAMPLE_READY_US);
+
+	/* check MTK_AUXADC_CON2 if auxadc is idle */
+	ret = readl_poll_timeout(adc_dev->reg_base + MT6577_AUXADC_CON2, val,
+				 ((val & MT6577_AUXADC_STA) == 0),
+				 MT6577_AUXADC_SLEEP_US,
+				 MT6577_AUXADC_TIMEOUT_US);
+	if (ret < 0) {
+		dev_err(indio_dev->dev.parent,
+			"wait for auxadc idle time out\n");
+		goto err_timeout;
+	}
+
+	/* read channel and make sure ready bit == 1 */
+	ret = readl_poll_timeout(reg_channel, val,
+				 ((val & MT6577_AUXADC_RDY0) != 0),
+				 MT6577_AUXADC_SLEEP_US,
+				 MT6577_AUXADC_TIMEOUT_US);
+	if (ret < 0) {
+		dev_err(indio_dev->dev.parent,
+			"wait for channel[%d] data ready time out\n",
+			chan->channel);
+		goto err_timeout;
+	}
+
+	/* read data */
+	val = readl(reg_channel) & MT6577_AUXADC_DAT_MASK;
+
+	mutex_unlock(&adc_dev->lock);
+
+	return val;
+
+err_timeout:
+
+	mutex_unlock(&adc_dev->lock);
+
+	return -ETIMEDOUT;
+}
+
+static int mt6577_auxadc_read_raw(struct iio_dev *indio_dev,
+				  struct iio_chan_spec const *chan,
+				  int *val,
+				  int *val2,
+				  long info)
+{
+	switch (info) {
+	case IIO_CHAN_INFO_PROCESSED:
+		*val = mt6577_auxadc_read(indio_dev, chan);
+		if (*val < 0) {
+			dev_err(indio_dev->dev.parent,
+				"failed to sample data on channel[%d]\n",
+				chan->channel);
+			return *val;
+		}
+		return IIO_VAL_INT;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_info mt6577_auxadc_info = {
+	.read_raw = &mt6577_auxadc_read_raw,
+};
+
+static int __maybe_unused mt6577_auxadc_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev);
+	int ret;
+
+	ret = clk_prepare_enable(adc_dev->adc_clk);
+	if (ret) {
+		pr_err("failed to enable auxadc clock\n");
+		return ret;
+	}
+
+	mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC,
+			      MT6577_AUXADC_PDN_EN, 0);
+	mdelay(MT6577_AUXADC_POWER_READY_MS);
+
+	return 0;
+}
+
+static int __maybe_unused mt6577_auxadc_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev);
+
+	mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC,
+			      0, MT6577_AUXADC_PDN_EN);
+	clk_disable_unprepare(adc_dev->adc_clk);
+
+	return 0;
+}
+
+static int mt6577_auxadc_probe(struct platform_device *pdev)
+{
+	struct mt6577_auxadc_device *adc_dev;
+	unsigned long adc_clk_rate;
+	struct resource *res;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc_dev));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	adc_dev = iio_priv(indio_dev);
+	indio_dev->dev.parent = &pdev->dev;
+	indio_dev->name = dev_name(&pdev->dev);
+	indio_dev->info = &mt6577_auxadc_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = mt6577_auxadc_iio_channels;
+	indio_dev->num_channels = ARRAY_SIZE(mt6577_auxadc_iio_channels);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	adc_dev->reg_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(adc_dev->reg_base)) {
+		dev_err(&pdev->dev, "failed to get auxadc base address\n");
+		return PTR_ERR(adc_dev->reg_base);
+	}
+
+	adc_dev->adc_clk = devm_clk_get(&pdev->dev, "main");
+	if (IS_ERR(adc_dev->adc_clk)) {
+		dev_err(&pdev->dev, "failed to get auxadc clock\n");
+		return PTR_ERR(adc_dev->adc_clk);
+	}
+
+	ret = clk_prepare_enable(adc_dev->adc_clk);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to enable auxadc clock\n");
+		return ret;
+	}
+
+	adc_clk_rate = clk_get_rate(adc_dev->adc_clk);
+	if (!adc_clk_rate) {
+		ret = -EINVAL;
+		dev_err(&pdev->dev, "null clock rate\n");
+		goto err_disable_clk;
+	}
+
+	mutex_init(&adc_dev->lock);
+
+	mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC,
+			      MT6577_AUXADC_PDN_EN, 0);
+	mdelay(MT6577_AUXADC_POWER_READY_MS);
+
+	platform_set_drvdata(pdev, indio_dev);
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to register iio device\n");
+		goto err_power_off;
+	}
+
+	return 0;
+
+err_power_off:
+	mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC,
+			      0, MT6577_AUXADC_PDN_EN);
+err_disable_clk:
+	clk_disable_unprepare(adc_dev->adc_clk);
+	return ret;
+}
+
+static int mt6577_auxadc_remove(struct platform_device *pdev)
+{
+	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+	struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+
+	mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC,
+			      0, MT6577_AUXADC_PDN_EN);
+
+	clk_disable_unprepare(adc_dev->adc_clk);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(mt6577_auxadc_pm_ops,
+			 mt6577_auxadc_suspend,
+			 mt6577_auxadc_resume);
+
+static const struct of_device_id mt6577_auxadc_of_match[] = {
+	{ .compatible = "mediatek,mt2701-auxadc", },
+	{ .compatible = "mediatek,mt2712-auxadc", },
+	{ .compatible = "mediatek,mt7622-auxadc", },
+	{ .compatible = "mediatek,mt8173-auxadc", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, mt6577_auxadc_of_match);
+
+static struct platform_driver mt6577_auxadc_driver = {
+	.driver = {
+		.name   = "mt6577-auxadc",
+		.of_match_table = mt6577_auxadc_of_match,
+		.pm = &mt6577_auxadc_pm_ops,
+	},
+	.probe	= mt6577_auxadc_probe,
+	.remove	= mt6577_auxadc_remove,
+};
+module_platform_driver(mt6577_auxadc_driver);
+
+MODULE_AUTHOR("Zhiyong Tao <zhiyong.tao@mediatek.com>");
+MODULE_DESCRIPTION("MTK AUXADC Device Driver");
+MODULE_LICENSE("GPL v2");