staging:iio:adc:spear Move out of staging.

There are some unanswered questions due to disagreements between the code
and various datasheets (including between different datasheets for the same
part).

I don't think that is necessarily a reason to keep it in staging however.
I'm partly posting this patch inorder to reignite debate and with a bit
of luck find someone who has one of these to test!

Signed-off-by: Jonathan Cameron <jic23@kernel.org>

3 files changed, 0 insertions, 406 deletions

diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig
index deff89973d53..0ad5c44042b2 100644
--- a/drivers/staging/iio/adc/Kconfig
+++ b/drivers/staging/iio/adc/Kconfig
@@ -92,14 +92,4 @@ config LPC32XX_ADC
 	  activate only one via device tree selection.  Provides direct access
 	  via sysfs.
 
-config SPEAR_ADC
-	tristate "ST SPEAr ADC"
-	depends on PLAT_SPEAR || COMPILE_TEST
-	depends on HAS_IOMEM
-	help
-	  Say yes here to build support for the integrated ADC inside the
-	  ST SPEAr SoC. Provides direct access via sysfs.
-
-	  To compile this driver as a module, choose M here: the
-	  module will be called spear_adc.
 endmenu
diff --git a/drivers/staging/iio/adc/Makefile b/drivers/staging/iio/adc/Makefile
index ac09485923b6..e7098dedeb75 100644
--- a/drivers/staging/iio/adc/Makefile
+++ b/drivers/staging/iio/adc/Makefile
@@ -11,4 +11,3 @@ obj-$(CONFIG_AD7816) += ad7816.o
 obj-$(CONFIG_AD7192) += ad7192.o
 obj-$(CONFIG_AD7280) += ad7280a.o
 obj-$(CONFIG_LPC32XX_ADC) += lpc32xx_adc.o
-obj-$(CONFIG_SPEAR_ADC) += spear_adc.o
diff --git a/drivers/staging/iio/adc/spear_adc.c b/drivers/staging/iio/adc/spear_adc.c
deleted file mode 100644
index 5dd61f6a57b9..000000000000
--- a/drivers/staging/iio/adc/spear_adc.c
+++ /dev/null
@@ -1,395 +0,0 @@
-/*
- * ST SPEAr ADC driver
- *
- * Copyright 2012 Stefan Roese <sr@denx.de>
- *
- * Licensed under the GPL-2.
- */
-
-#include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/interrupt.h>
-#include <linux/device.h>
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <linux/io.h>
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <linux/completion.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
-
-#include <linux/iio/iio.h>
-#include <linux/iio/sysfs.h>
-
-/* SPEAR registers definitions */
-#define SPEAR600_ADC_SCAN_RATE_LO(x)	((x) & 0xFFFF)
-#define SPEAR600_ADC_SCAN_RATE_HI(x)	(((x) >> 0x10) & 0xFFFF)
-#define SPEAR_ADC_CLK_LOW(x)		(((x) & 0xf) << 0)
-#define SPEAR_ADC_CLK_HIGH(x)		(((x) & 0xf) << 4)
-
-/* Bit definitions for SPEAR_ADC_STATUS */
-#define SPEAR_ADC_STATUS_START_CONVERSION	BIT(0)
-#define SPEAR_ADC_STATUS_CHANNEL_NUM(x)		((x) << 1)
-#define SPEAR_ADC_STATUS_ADC_ENABLE		BIT(4)
-#define SPEAR_ADC_STATUS_AVG_SAMPLE(x)		((x) << 5)
-#define SPEAR_ADC_STATUS_VREF_INTERNAL		BIT(9)
-
-#define SPEAR_ADC_DATA_MASK		0x03ff
-#define SPEAR_ADC_DATA_BITS		10
-
-#define SPEAR_ADC_MOD_NAME "spear-adc"
-
-#define SPEAR_ADC_CHANNEL_NUM		8
-
-#define SPEAR_ADC_CLK_MIN			2500000
-#define SPEAR_ADC_CLK_MAX			20000000
-
-struct adc_regs_spear3xx {
-	u32 status;
-	u32 average;
-	u32 scan_rate;
-	u32 clk;	/* Not avail for 1340 & 1310 */
-	u32 ch_ctrl[SPEAR_ADC_CHANNEL_NUM];
-	u32 ch_data[SPEAR_ADC_CHANNEL_NUM];
-};
-
-struct chan_data {
-	u32 lsb;
-	u32 msb;
-};
-
-struct adc_regs_spear6xx {
-	u32 status;
-	u32 pad[2];
-	u32 clk;
-	u32 ch_ctrl[SPEAR_ADC_CHANNEL_NUM];
-	struct chan_data ch_data[SPEAR_ADC_CHANNEL_NUM];
-	u32 scan_rate_lo;
-	u32 scan_rate_hi;
-	struct chan_data average;
-};
-
-struct spear_adc_state {
-	struct device_node *np;
-	struct adc_regs_spear3xx __iomem *adc_base_spear3xx;
-	struct adc_regs_spear6xx __iomem *adc_base_spear6xx;
-	struct clk *clk;
-	struct completion completion;
-	u32 current_clk;
-	u32 sampling_freq;
-	u32 avg_samples;
-	u32 vref_external;
-	u32 value;
-};
-
-/*
- * Functions to access some SPEAr ADC register. Abstracted into
- * static inline functions, because of different register offsets
- * on different SoC variants (SPEAr300 vs SPEAr600 etc).
- */
-static void spear_adc_set_status(struct spear_adc_state *st, u32 val)
-{
-	__raw_writel(val, &st->adc_base_spear6xx->status);
-}
-
-static void spear_adc_set_clk(struct spear_adc_state *st, u32 val)
-{
-	u32 clk_high, clk_low, count;
-	u32 apb_clk = clk_get_rate(st->clk);
-
-	count = DIV_ROUND_UP(apb_clk, val);
-	clk_low = count / 2;
-	clk_high = count - clk_low;
-	st->current_clk = apb_clk / count;
-
-	__raw_writel(SPEAR_ADC_CLK_LOW(clk_low) | SPEAR_ADC_CLK_HIGH(clk_high),
-		     &st->adc_base_spear6xx->clk);
-}
-
-static void spear_adc_set_ctrl(struct spear_adc_state *st, int n,
-			       u32 val)
-{
-	__raw_writel(val, &st->adc_base_spear6xx->ch_ctrl[n]);
-}
-
-static u32 spear_adc_get_average(struct spear_adc_state *st)
-{
-	if (of_device_is_compatible(st->np, "st,spear600-adc")) {
-		return __raw_readl(&st->adc_base_spear6xx->average.msb) &
-			SPEAR_ADC_DATA_MASK;
-	} else {
-		return __raw_readl(&st->adc_base_spear3xx->average) &
-			SPEAR_ADC_DATA_MASK;
-	}
-}
-
-static void spear_adc_set_scanrate(struct spear_adc_state *st, u32 rate)
-{
-	if (of_device_is_compatible(st->np, "st,spear600-adc")) {
-		__raw_writel(SPEAR600_ADC_SCAN_RATE_LO(rate),
-			     &st->adc_base_spear6xx->scan_rate_lo);
-		__raw_writel(SPEAR600_ADC_SCAN_RATE_HI(rate),
-			     &st->adc_base_spear6xx->scan_rate_hi);
-	} else {
-		__raw_writel(rate, &st->adc_base_spear3xx->scan_rate);
-	}
-}
-
-static int spear_adc_read_raw(struct iio_dev *indio_dev,
-			      struct iio_chan_spec const *chan,
-			      int *val,
-			      int *val2,
-			      long mask)
-{
-	struct spear_adc_state *st = iio_priv(indio_dev);
-	u32 status;
-
-	switch (mask) {
-	case IIO_CHAN_INFO_RAW:
-		mutex_lock(&indio_dev->mlock);
-
-		status = SPEAR_ADC_STATUS_CHANNEL_NUM(chan->channel) |
-			SPEAR_ADC_STATUS_AVG_SAMPLE(st->avg_samples) |
-			SPEAR_ADC_STATUS_START_CONVERSION |
-			SPEAR_ADC_STATUS_ADC_ENABLE;
-		if (st->vref_external == 0)
-			status |= SPEAR_ADC_STATUS_VREF_INTERNAL;
-
-		spear_adc_set_status(st, status);
-		wait_for_completion(&st->completion); /* set by ISR */
-		*val = st->value;
-
-		mutex_unlock(&indio_dev->mlock);
-
-		return IIO_VAL_INT;
-
-	case IIO_CHAN_INFO_SCALE:
-		*val = st->vref_external;
-		*val2 = SPEAR_ADC_DATA_BITS;
-		return IIO_VAL_FRACTIONAL_LOG2;
-	case IIO_CHAN_INFO_SAMP_FREQ:
-		*val = st->current_clk;
-		return IIO_VAL_INT;
-	}
-
-	return -EINVAL;
-}
-
-static int spear_adc_write_raw(struct iio_dev *indio_dev,
-			       struct iio_chan_spec const *chan,
-			       int val,
-			       int val2,
-			       long mask)
-{
-	struct spear_adc_state *st = iio_priv(indio_dev);
-	int ret = 0;
-
-	if (mask != IIO_CHAN_INFO_SAMP_FREQ)
-		return -EINVAL;
-
-	mutex_lock(&indio_dev->mlock);
-
-	if ((val < SPEAR_ADC_CLK_MIN) ||
-	    (val > SPEAR_ADC_CLK_MAX) ||
-	    (val2 != 0)) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	spear_adc_set_clk(st, val);
-
-out:
-	mutex_unlock(&indio_dev->mlock);
-	return ret;
-}
-
-#define SPEAR_ADC_CHAN(idx) {				\
-	.type = IIO_VOLTAGE,				\
-	.indexed = 1,					\
-	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
-	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
-	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
-	.channel = idx,					\
-}
-
-static const struct iio_chan_spec spear_adc_iio_channels[] = {
-	SPEAR_ADC_CHAN(0),
-	SPEAR_ADC_CHAN(1),
-	SPEAR_ADC_CHAN(2),
-	SPEAR_ADC_CHAN(3),
-	SPEAR_ADC_CHAN(4),
-	SPEAR_ADC_CHAN(5),
-	SPEAR_ADC_CHAN(6),
-	SPEAR_ADC_CHAN(7),
-};
-
-static irqreturn_t spear_adc_isr(int irq, void *dev_id)
-{
-	struct spear_adc_state *st = dev_id;
-
-	/* Read value to clear IRQ */
-	st->value = spear_adc_get_average(st);
-	complete(&st->completion);
-
-	return IRQ_HANDLED;
-}
-
-static int spear_adc_configure(struct spear_adc_state *st)
-{
-	int i;
-
-	/* Reset ADC core */
-	spear_adc_set_status(st, 0);
-	__raw_writel(0, &st->adc_base_spear6xx->clk);
-	for (i = 0; i < 8; i++)
-		spear_adc_set_ctrl(st, i, 0);
-	spear_adc_set_scanrate(st, 0);
-
-	spear_adc_set_clk(st, st->sampling_freq);
-
-	return 0;
-}
-
-static const struct iio_info spear_adc_info = {
-	.read_raw = &spear_adc_read_raw,
-	.write_raw = &spear_adc_write_raw,
-	.driver_module = THIS_MODULE,
-};
-
-static int spear_adc_probe(struct platform_device *pdev)
-{
-	struct device_node *np = pdev->dev.of_node;
-	struct device *dev = &pdev->dev;
-	struct spear_adc_state *st;
-	struct resource *res;
-	struct iio_dev *indio_dev = NULL;
-	int ret = -ENODEV;
-	int irq;
-
-	indio_dev = devm_iio_device_alloc(dev, sizeof(struct spear_adc_state));
-	if (!indio_dev) {
-		dev_err(dev, "failed allocating iio device\n");
-		return -ENOMEM;
-	}
-
-	st = iio_priv(indio_dev);
-	st->np = np;
-
-	/*
-	 * SPEAr600 has a different register layout than other SPEAr SoC's
-	 * (e.g. SPEAr3xx). Let's provide two register base addresses
-	 * to support multi-arch kernels.
-	 */
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	st->adc_base_spear6xx = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(st->adc_base_spear6xx))
-		return PTR_ERR(st->adc_base_spear6xx);
-
-	st->adc_base_spear3xx =
-		(struct adc_regs_spear3xx __iomem *)st->adc_base_spear6xx;
-
-	st->clk = devm_clk_get(dev, NULL);
-	if (IS_ERR(st->clk)) {
-		dev_err(dev, "failed getting clock\n");
-		return PTR_ERR(st->clk);
-	}
-
-	ret = clk_prepare_enable(st->clk);
-	if (ret) {
-		dev_err(dev, "failed enabling clock\n");
-		return ret;
-	}
-
-	irq = platform_get_irq(pdev, 0);
-	if (irq <= 0) {
-		dev_err(dev, "failed getting interrupt resource\n");
-		ret = -EINVAL;
-		goto errout2;
-	}
-
-	ret = devm_request_irq(dev, irq, spear_adc_isr, 0, SPEAR_ADC_MOD_NAME,
-			       st);
-	if (ret < 0) {
-		dev_err(dev, "failed requesting interrupt\n");
-		goto errout2;
-	}
-
-	if (of_property_read_u32(np, "sampling-frequency",
-				 &st->sampling_freq)) {
-		dev_err(dev, "sampling-frequency missing in DT\n");
-		ret = -EINVAL;
-		goto errout2;
-	}
-
-	/*
-	 * Optional avg_samples defaults to 0, resulting in single data
-	 * conversion
-	 */
-	of_property_read_u32(np, "average-samples", &st->avg_samples);
-
-	/*
-	 * Optional vref_external defaults to 0, resulting in internal vref
-	 * selection
-	 */
-	of_property_read_u32(np, "vref-external", &st->vref_external);
-
-	spear_adc_configure(st);
-
-	platform_set_drvdata(pdev, indio_dev);
-
-	init_completion(&st->completion);
-
-	indio_dev->name = SPEAR_ADC_MOD_NAME;
-	indio_dev->dev.parent = dev;
-	indio_dev->info = &spear_adc_info;
-	indio_dev->modes = INDIO_DIRECT_MODE;
-	indio_dev->channels = spear_adc_iio_channels;
-	indio_dev->num_channels = ARRAY_SIZE(spear_adc_iio_channels);
-
-	ret = iio_device_register(indio_dev);
-	if (ret)
-		goto errout2;
-
-	dev_info(dev, "SPEAR ADC driver loaded, IRQ %d\n", irq);
-
-	return 0;
-
-errout2:
-	clk_disable_unprepare(st->clk);
-	return ret;
-}
-
-static int spear_adc_remove(struct platform_device *pdev)
-{
-	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
-	struct spear_adc_state *st = iio_priv(indio_dev);
-
-	iio_device_unregister(indio_dev);
-	clk_disable_unprepare(st->clk);
-
-	return 0;
-}
-
-#ifdef CONFIG_OF
-static const struct of_device_id spear_adc_dt_ids[] = {
-	{ .compatible = "st,spear600-adc", },
-	{ /* sentinel */ }
-};
-MODULE_DEVICE_TABLE(of, spear_adc_dt_ids);
-#endif
-
-static struct platform_driver spear_adc_driver = {
-	.probe		= spear_adc_probe,
-	.remove		= spear_adc_remove,
-	.driver		= {
-		.name	= SPEAR_ADC_MOD_NAME,
-		.of_match_table = of_match_ptr(spear_adc_dt_ids),
-	},
-};
-
-module_platform_driver(spear_adc_driver);
-
-MODULE_AUTHOR("Stefan Roese <sr@denx.de>");
-MODULE_DESCRIPTION("SPEAr ADC driver");
-MODULE_LICENSE("GPL");