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2024-02-20 102a0743326a03cd1a1202ceda21e175b7d3575c

 kernel/drivers/iio/adc/lpc32xx_adc.c
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@@ -1,39 +1,22 @@
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+// SPDX-License-Identifier: GPL-2.0+
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 /*
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  *  lpc32xx_adc.c - Support for ADC in LPC32XX
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  *
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  *  3-channel, 10-bit ADC
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  *
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  *  Copyright (C) 2011, 2012 Roland Stigge <stigge@antcom.de>
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- *
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- *  This program is free software; you can redistribute it and/or modify
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- *  it under the terms of the GNU General Public License as published by
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- *  the Free Software Foundation; either version 2 of the License, or
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- *  (at your option) any later version.
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- *
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- *  This program is distributed in the hope that it will be useful,
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- *  but WITHOUT ANY WARRANTY; without even the implied warranty of
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- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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- *  GNU General Public License for more details.
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- *
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- *  You should have received a copy of the GNU General Public License
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- *  along with this program; if not, write to the Free Software
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- *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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  */
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9
 
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-#include <linux/module.h>
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-#include <linux/platform_device.h>
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-#include <linux/interrupt.h>
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-#include <linux/device.h>
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-#include <linux/kernel.h>
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-#include <linux/slab.h>
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-#include <linux/io.h>
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 #include <linux/clk.h>
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-#include <linux/err.h>
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 #include <linux/completion.h>
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-#include <linux/of.h>
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-
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+#include <linux/err.h>
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 #include <linux/iio/iio.h>
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-#include <linux/iio/sysfs.h>
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+#include <linux/interrupt.h>
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+#include <linux/io.h>
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+#include <linux/module.h>
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+#include <linux/mod_devicetable.h>
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+#include <linux/platform_device.h>
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+#include <linux/regulator/consumer.h>
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20
 
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 /*
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  * LPC32XX registers definitions
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@@ -65,6 +48,7 @@
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 	void __iomem *adc_base;
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 	struct clk *clk;
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 	struct completion completion;
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+	struct regulator *vref;
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 	u32 value;
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 };
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@@ -77,7 +61,9 @@
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 {
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 	struct lpc32xx_adc_state *st = iio_priv(indio_dev);
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 	int ret;
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-	if (mask == IIO_CHAN_INFO_RAW) {
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+
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+	switch (mask) {
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+	case IIO_CHAN_INFO_RAW:
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 		mutex_lock(&indio_dev->mlock);
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 		ret = clk_prepare_enable(st->clk);
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 		if (ret) {
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@@ -97,28 +83,48 @@
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 		mutex_unlock(&indio_dev->mlock);
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 		return IIO_VAL_INT;
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-	}
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-	return -EINVAL;
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+	case IIO_CHAN_INFO_SCALE:
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+		*val = regulator_get_voltage(st->vref) / 1000;
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+		*val2 =  10;
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+
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+		return IIO_VAL_FRACTIONAL_LOG2;
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+	default:
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+		return -EINVAL;
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+	}
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 }
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 static const struct iio_info lpc32xx_adc_iio_info = {
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 	.read_raw = &lpc32xx_read_raw,
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 };
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-#define LPC32XX_ADC_CHANNEL(_index) {			\
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+#define LPC32XX_ADC_CHANNEL_BASE(_index)		\
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 	.type = IIO_VOLTAGE,				\
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 	.indexed = 1,					\
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 	.channel = _index,				\
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 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
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 	.address = LPC32XXAD_IN * _index,		\
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-	.scan_index = _index,				\
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+	.scan_index = _index,
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+
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+#define LPC32XX_ADC_CHANNEL(_index) {		\
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+	LPC32XX_ADC_CHANNEL_BASE(_index)	\
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+}
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+
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+#define LPC32XX_ADC_SCALE_CHANNEL(_index) {			\
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+	LPC32XX_ADC_CHANNEL_BASE(_index)			\
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+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE)	\
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 }
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 static const struct iio_chan_spec lpc32xx_adc_iio_channels[] = {
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 	LPC32XX_ADC_CHANNEL(0),
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 	LPC32XX_ADC_CHANNEL(1),
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 	LPC32XX_ADC_CHANNEL(2),
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+};
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+
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+static const struct iio_chan_spec lpc32xx_adc_iio_scale_channels[] = {
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+	LPC32XX_ADC_SCALE_CHANNEL(0),
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+	LPC32XX_ADC_SCALE_CHANNEL(1),
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+	LPC32XX_ADC_SCALE_CHANNEL(2),
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 };
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 static irqreturn_t lpc32xx_adc_isr(int irq, void *dev_id)
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@@ -167,10 +173,8 @@
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 	}
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 	irq = platform_get_irq(pdev, 0);
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-	if (irq <= 0) {
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-		dev_err(&pdev->dev, "failed getting interrupt resource\n");
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+	if (irq <= 0)
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 		return -ENXIO;
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-	}
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 	retval = devm_request_irq(&pdev->dev, irq, lpc32xx_adc_isr, 0,
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 				  LPC32XXAD_NAME, st);
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@@ -179,15 +183,22 @@
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 		return retval;
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 	}
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+	st->vref = devm_regulator_get(&pdev->dev, "vref");
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+	if (IS_ERR(st->vref)) {
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+		iodev->channels = lpc32xx_adc_iio_channels;
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+		dev_info(&pdev->dev,
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+			 "Missing vref regulator: No scaling available\n");
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+	} else {
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+		iodev->channels = lpc32xx_adc_iio_scale_channels;
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+	}
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+
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 	platform_set_drvdata(pdev, iodev);
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 	init_completion(&st->completion);
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 	iodev->name = LPC32XXAD_NAME;
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-	iodev->dev.parent = &pdev->dev;
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 	iodev->info = &lpc32xx_adc_iio_info;
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 	iodev->modes = INDIO_DIRECT_MODE;
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-	iodev->channels = lpc32xx_adc_iio_channels;
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 	iodev->num_channels = ARRAY_SIZE(lpc32xx_adc_iio_channels);
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 	retval = devm_iio_device_register(&pdev->dev, iodev);
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@@ -199,19 +210,17 @@
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 	return 0;
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 }
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-#ifdef CONFIG_OF
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 static const struct of_device_id lpc32xx_adc_match[] = {
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 	{ .compatible = "nxp,lpc3220-adc" },
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 	{},
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 };
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 MODULE_DEVICE_TABLE(of, lpc32xx_adc_match);
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-#endif
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 static struct platform_driver lpc32xx_adc_driver = {
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 	.probe		= lpc32xx_adc_probe,
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 	.driver		= {
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 		.name	= LPC32XXAD_NAME,
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-		.of_match_table = of_match_ptr(lpc32xx_adc_match),
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+		.of_match_table = lpc32xx_adc_match,
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 	},
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 };
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