1 files changed, 142 insertions, 173 deletions

diff --git a/drivers/staging/iio/adc/spear_adc.c b/drivers/staging/iio/adc/spear_adc.c
index 970d9edc73b6..c5492ba50751 100644
--- a/drivers/staging/iio/adc/spear_adc.c
+++ b/drivers/staging/iio/adc/spear_adc.c
@@ -22,39 +22,36 @@
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
 
-/*
- * SPEAR registers definitions
- */
-
-#define SCAN_RATE_LO(x)		((x) & 0xFFFF)
-#define SCAN_RATE_HI(x)		(((x) >> 0x10) & 0xFFFF)
-#define CLK_LOW(x)		(((x) & 0xf) << 0)
-#define CLK_HIGH(x)		(((x) & 0xf) << 4)
+/* 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 START_CONVERSION	(1 << 0)
-#define CHANNEL_NUM(x)		((x) << 1)
-#define ADC_ENABLE		(1 << 4)
-#define AVG_SAMPLE(x)		((x) << 5)
-#define VREF_INTERNAL		(1 << 9)
+#define SPEAR_ADC_STATUS_START_CONVERSION	(1 << 0)
+#define SPEAR_ADC_STATUS_CHANNEL_NUM(x)		((x) << 1)
+#define SPEAR_ADC_STATUS_ADC_ENABLE		(1 << 4)
+#define SPEAR_ADC_STATUS_AVG_SAMPLE(x)		((x) << 5)
+#define SPEAR_ADC_STATUS_VREF_INTERNAL		(1 << 9)
 
-#define DATA_MASK		0x03ff
-#define DATA_BITS		10
+#define SPEAR_ADC_DATA_MASK		0x03ff
+#define SPEAR_ADC_DATA_BITS		10
 
-#define MOD_NAME "spear-adc"
+#define SPEAR_ADC_MOD_NAME "spear-adc"
 
-#define ADC_CHANNEL_NUM		8
+#define SPEAR_ADC_CHANNEL_NUM		8
 
-#define CLK_MIN			2500000
-#define CLK_MAX			20000000
+#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[ADC_CHANNEL_NUM];
-	u32 ch_data[ADC_CHANNEL_NUM];
+	u32 ch_ctrl[SPEAR_ADC_CHANNEL_NUM];
+	u32 ch_data[SPEAR_ADC_CHANNEL_NUM];
 };
 
 struct chan_data {
@@ -66,14 +63,14 @@ struct adc_regs_spear6xx {
 	u32 status;
 	u32 pad[2];
 	u32 clk;
-	u32 ch_ctrl[ADC_CHANNEL_NUM];
-	struct chan_data ch_data[ADC_CHANNEL_NUM];
+	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_info {
+struct spear_adc_state {
 	struct device_node *np;
 	struct adc_regs_spear3xx __iomem *adc_base_spear3xx;
 	struct adc_regs_spear6xx __iomem *adc_base_spear6xx;
@@ -91,100 +88,129 @@ struct spear_adc_info {
  * 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_info *info, u32 val)
+static void spear_adc_set_status(struct spear_adc_state *st, u32 val)
 {
-	__raw_writel(val, &info->adc_base_spear6xx->status);
+	__raw_writel(val, &st->adc_base_spear6xx->status);
 }
 
-static void spear_adc_set_clk(struct spear_adc_info *info, u32 val)
+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(info->clk);
+	u32 apb_clk = clk_get_rate(st->clk);
 
 	count = (apb_clk + val - 1) / val;
 	clk_low = count / 2;
 	clk_high = count - clk_low;
-	info->current_clk = apb_clk / count;
+	st->current_clk = apb_clk / count;
 
-	__raw_writel(CLK_LOW(clk_low) | CLK_HIGH(clk_high),
-		     &info->adc_base_spear6xx->clk);
+	__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_info *info, int n,
+static void spear_adc_set_ctrl(struct spear_adc_state *st, int n,
 			       u32 val)
 {
-	__raw_writel(val, &info->adc_base_spear6xx->ch_ctrl[n]);
+	__raw_writel(val, &st->adc_base_spear6xx->ch_ctrl[n]);
 }
 
-static u32 spear_adc_get_average(struct spear_adc_info *info)
+static u32 spear_adc_get_average(struct spear_adc_state *st)
 {
-	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
-		return __raw_readl(&info->adc_base_spear6xx->average.msb) &
-			DATA_MASK;
+	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(&info->adc_base_spear3xx->average) &
-			DATA_MASK;
+		return __raw_readl(&st->adc_base_spear3xx->average) &
+			SPEAR_ADC_DATA_MASK;
 	}
 }
 
-static void spear_adc_set_scanrate(struct spear_adc_info *info, u32 rate)
+static void spear_adc_set_scanrate(struct spear_adc_state *st, u32 rate)
 {
-	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
-		__raw_writel(SCAN_RATE_LO(rate),
-			     &info->adc_base_spear6xx->scan_rate_lo);
-		__raw_writel(SCAN_RATE_HI(rate),
-			     &info->adc_base_spear6xx->scan_rate_hi);
+	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, &info->adc_base_spear3xx->scan_rate);
+		__raw_writel(rate, &st->adc_base_spear3xx->scan_rate);
 	}
 }
 
-static int spear_read_raw(struct iio_dev *indio_dev,
-			  struct iio_chan_spec const *chan,
-			  int *val,
-			  int *val2,
-			  long mask)
+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_info *info = iio_priv(indio_dev);
+	struct spear_adc_state *st = iio_priv(indio_dev);
 	u32 status;
 
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
 		mutex_lock(&indio_dev->mlock);
 
-		status = CHANNEL_NUM(chan->channel) |
-			AVG_SAMPLE(info->avg_samples) |
-			START_CONVERSION | ADC_ENABLE;
-		if (info->vref_external == 0)
-			status |= VREF_INTERNAL;
+		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(info, status);
-		wait_for_completion(&info->completion); /* set by ISR */
-		*val = info->value;
+		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 = info->vref_external;
-		*val2 = DATA_BITS;
+		*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,					\
-	.scan_type = {					\
-		.sign = 'u',				\
-		.storagebits = 16,			\
-	},						\
 }
 
 static const struct iio_chan_spec spear_adc_iio_channels[] = {
@@ -200,92 +226,34 @@ static const struct iio_chan_spec spear_adc_iio_channels[] = {
 
 static irqreturn_t spear_adc_isr(int irq, void *dev_id)
 {
-	struct spear_adc_info *info = (struct spear_adc_info *)dev_id;
+	struct spear_adc_state *st = (struct spear_adc_state *)dev_id;
 
 	/* Read value to clear IRQ */
-	info->value = spear_adc_get_average(info);
-	complete(&info->completion);
+	st->value = spear_adc_get_average(st);
+	complete(&st->completion);
 
 	return IRQ_HANDLED;
 }
 
-static int spear_adc_configure(struct spear_adc_info *info)
+static int spear_adc_configure(struct spear_adc_state *st)
 {
 	int i;
 
 	/* Reset ADC core */
-	spear_adc_set_status(info, 0);
-	__raw_writel(0, &info->adc_base_spear6xx->clk);
+	spear_adc_set_status(st, 0);
+	__raw_writel(0, &st->adc_base_spear6xx->clk);
 	for (i = 0; i < 8; i++)
-		spear_adc_set_ctrl(info, i, 0);
-	spear_adc_set_scanrate(info, 0);
+		spear_adc_set_ctrl(st, i, 0);
+	spear_adc_set_scanrate(st, 0);
 
-	spear_adc_set_clk(info, info->sampling_freq);
+	spear_adc_set_clk(st, st->sampling_freq);
 
 	return 0;
 }
 
-static ssize_t spear_adc_read_frequency(struct device *dev,
-					struct device_attribute *attr,
-					char *buf)
-{
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-	struct spear_adc_info *info = iio_priv(indio_dev);
-
-	return sprintf(buf, "%d\n", info->current_clk);
-}
-
-static ssize_t spear_adc_write_frequency(struct device *dev,
-					 struct device_attribute *attr,
-					 const char *buf,
-					 size_t len)
-{
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-	struct spear_adc_info *info = iio_priv(indio_dev);
-	u32 clk_high, clk_low, count;
-	u32 apb_clk = clk_get_rate(info->clk);
-	unsigned long lval;
-	int ret;
-
-	ret = kstrtoul(buf, 10, &lval);
-	if (ret)
-		return ret;
-
-	mutex_lock(&indio_dev->mlock);
-
-	if ((lval < CLK_MIN) || (lval > CLK_MAX)) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	count = (apb_clk + lval - 1) / lval;
-	clk_low = count / 2;
-	clk_high = count - clk_low;
-	info->current_clk = apb_clk / count;
-	spear_adc_set_clk(info, lval);
-
-out:
-	mutex_unlock(&indio_dev->mlock);
-
-	return ret ? ret : len;
-}
-
-static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
-			      spear_adc_read_frequency,
-			      spear_adc_write_frequency);
-
-static struct attribute *spear_attributes[] = {
-	&iio_dev_attr_sampling_frequency.dev_attr.attr,
-	NULL
-};
-
-static const struct attribute_group spear_attribute_group = {
-	.attrs = spear_attributes,
-};
-
-static const struct iio_info spear_adc_iio_info = {
-	.read_raw = &spear_read_raw,
-	.attrs = &spear_attribute_group,
+static const struct iio_info spear_adc_info = {
+	.read_raw = &spear_adc_read_raw,
+	.write_raw = &spear_adc_write_raw,
 	.driver_module = THIS_MODULE,
 };
 
@@ -293,40 +261,40 @@ 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_info *info;
-	struct iio_dev *iodev = NULL;
+	struct spear_adc_state *st;
+	struct iio_dev *indio_dev = NULL;
 	int ret = -ENODEV;
 	int irq;
 
-	iodev = devm_iio_device_alloc(dev, sizeof(struct spear_adc_info));
-	if (!iodev) {
+	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;
 	}
 
-	info = iio_priv(iodev);
-	info->np = np;
+	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.
 	 */
-	info->adc_base_spear6xx = of_iomap(np, 0);
-	if (!info->adc_base_spear6xx) {
+	st->adc_base_spear6xx = of_iomap(np, 0);
+	if (!st->adc_base_spear6xx) {
 		dev_err(dev, "failed mapping memory\n");
 		return -ENOMEM;
 	}
-	info->adc_base_spear3xx =
-		(struct adc_regs_spear3xx __iomem *)info->adc_base_spear6xx;
+	st->adc_base_spear3xx =
+		(struct adc_regs_spear3xx __iomem *)st->adc_base_spear6xx;
 
-	info->clk = clk_get(dev, NULL);
-	if (IS_ERR(info->clk)) {
+	st->clk = clk_get(dev, NULL);
+	if (IS_ERR(st->clk)) {
 		dev_err(dev, "failed getting clock\n");
 		goto errout1;
 	}
 
-	ret = clk_prepare_enable(info->clk);
+	ret = clk_prepare_enable(st->clk);
 	if (ret) {
 		dev_err(dev, "failed enabling clock\n");
 		goto errout2;
@@ -339,14 +307,15 @@ static int spear_adc_probe(struct platform_device *pdev)
 		goto errout3;
 	}
 
-	ret = devm_request_irq(dev, irq, spear_adc_isr, 0, MOD_NAME, info);
+	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 errout3;
 	}
 
 	if (of_property_read_u32(np, "sampling-frequency",
-				 &info->sampling_freq)) {
+				 &st->sampling_freq)) {
 		dev_err(dev, "sampling-frequency missing in DT\n");
 		ret = -EINVAL;
 		goto errout3;
@@ -356,28 +325,28 @@ static int spear_adc_probe(struct platform_device *pdev)
 	 * Optional avg_samples defaults to 0, resulting in single data
 	 * conversion
 	 */
-	of_property_read_u32(np, "average-samples", &info->avg_samples);
+	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", &info->vref_external);
+	of_property_read_u32(np, "vref-external", &st->vref_external);
 
-	spear_adc_configure(info);
+	spear_adc_configure(st);
 
-	platform_set_drvdata(pdev, iodev);
+	platform_set_drvdata(pdev, indio_dev);
 
-	init_completion(&info->completion);
+	init_completion(&st->completion);
 
-	iodev->name = MOD_NAME;
-	iodev->dev.parent = dev;
-	iodev->info = &spear_adc_iio_info;
-	iodev->modes = INDIO_DIRECT_MODE;
-	iodev->channels = spear_adc_iio_channels;
-	iodev->num_channels = ARRAY_SIZE(spear_adc_iio_channels);
+	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(iodev);
+	ret = iio_device_register(indio_dev);
 	if (ret)
 		goto errout3;
 
@@ -386,23 +355,23 @@ static int spear_adc_probe(struct platform_device *pdev)
 	return 0;
 
 errout3:
-	clk_disable_unprepare(info->clk);
+	clk_disable_unprepare(st->clk);
 errout2:
-	clk_put(info->clk);
+	clk_put(st->clk);
 errout1:
-	iounmap(info->adc_base_spear6xx);
+	iounmap(st->adc_base_spear6xx);
 	return ret;
 }
 
 static int spear_adc_remove(struct platform_device *pdev)
 {
-	struct iio_dev *iodev = platform_get_drvdata(pdev);
-	struct spear_adc_info *info = iio_priv(iodev);
+	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+	struct spear_adc_state *st = iio_priv(indio_dev);
 
-	iio_device_unregister(iodev);
-	clk_disable_unprepare(info->clk);
-	clk_put(info->clk);
-	iounmap(info->adc_base_spear6xx);
+	iio_device_unregister(indio_dev);
+	clk_disable_unprepare(st->clk);
+	clk_put(st->clk);
+	iounmap(st->adc_base_spear6xx);
 
 	return 0;
 }
@@ -419,7 +388,7 @@ static struct platform_driver spear_adc_driver = {
 	.probe		= spear_adc_probe,
 	.remove		= spear_adc_remove,
 	.driver		= {
-		.name	= MOD_NAME,
+		.name	= SPEAR_ADC_MOD_NAME,
 		.owner	= THIS_MODULE,
 		.of_match_table = of_match_ptr(spear_adc_dt_ids),
 	},