iio: Minor cleanups to spear ADC driver followed by staging graduation.

Signed-off-by Jonathan Cameron <[email protected]>

Acked-by Stefan Roese <[email protected]>

---
 drivers/staging/iio/adc/spear_adc.c | 73 ++++++++++++++++++-------------------
 1 file changed, 36 insertions(+), 37 deletions(-)

drivers/staging/iio/adc/spear_adc.c +32 -34

index 970d9ed..9234e05 100644
@@ -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 {

@@ -66,8 +63,8 @@ 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;

@@ -106,7 +103,7 @@ static void spear_adc_set_clk(struct spear_adc_info *info, u32 val)
 	clk_high = count - clk_low;
 	info->current_clk = apb_clk / count;
 
-	__raw_writel(CLK_LOW(clk_low) | CLK_HIGH(clk_high),
+	__raw_writel(SPEAR_ADC_CLK_LOW(clk_low) | SPEAR_ADC_CLK_HIGH(clk_high),
 		     &info->adc_base_spear6xx->clk);
 }
 

@@ -120,19 +117,19 @@ static u32 spear_adc_get_average(struct spear_adc_info *info)
 {
 	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
 		return __raw_readl(&info->adc_base_spear6xx->average.msb) &
-			DATA_MASK;
+			SPEAR_ADC_DATA_MASK;
 	} else {
 		return __raw_readl(&info->adc_base_spear3xx->average) &
-			DATA_MASK;
+			SPEAR_ADC_DATA_MASK;
 	}
 }
 
 static void spear_adc_set_scanrate(struct spear_adc_info *info, u32 rate)
 {
 	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
-		__raw_writel(SCAN_RATE_LO(rate),
+		__raw_writel(SPEAR600_ADC_SCAN_RATE_LO(rate),
 			     &info->adc_base_spear6xx->scan_rate_lo);
-		__raw_writel(SCAN_RATE_HI(rate),
+		__raw_writel(SPEAR600_ADC_SCAN_RATE_HI(rate),
 			     &info->adc_base_spear6xx->scan_rate_hi);
 	} else {
 		__raw_writel(rate, &info->adc_base_spear3xx->scan_rate);

@@ -152,11 +149,12 @@ static int spear_read_raw(struct iio_dev *indio_dev,
 	case IIO_CHAN_INFO_RAW:
 		mutex_lock(&indio_dev->mlock);
 
-		status = CHANNEL_NUM(chan->channel) |
-			AVG_SAMPLE(info->avg_samples) |
-			START_CONVERSION | ADC_ENABLE;
+		status = SPEAR_ADC_STATUS_CHANNEL_NUM(chan->channel) |
+			SPEAR_ADC_STATUS_AVG_SAMPLE(info->avg_samples) |
+			SPEAR_ADC_STATUS_START_CONVERSION |
+			SPEAR_ADC_STATUS_ADC_ENABLE;
 		if (info->vref_external == 0)
-			status |= VREF_INTERNAL;
+			status |= SPEAR_ADC_STATUS_VREF_INTERNAL;
 
 		spear_adc_set_status(info, status);
 		wait_for_completion(&info->completion); /* set by ISR */

@@ -168,7 +166,7 @@ static int spear_read_raw(struct iio_dev *indio_dev,
 
 	case IIO_CHAN_INFO_SCALE:
 		*val = info->vref_external;
-		*val2 = DATA_BITS;
+		*val2 = SPEAR_ADC_DATA_BITS;
 		return IIO_VAL_FRACTIONAL_LOG2;
 	}
 

@@ -253,7 +251,7 @@ static ssize_t spear_adc_write_frequency(struct device *dev,
 
 	mutex_lock(&indio_dev->mlock);
 
-	if ((lval < CLK_MIN) || (lval > CLK_MAX)) {
+	if ((lval < SPEAR_ADC_CLK_MIN) || (lval > SPEAR_ADC_CLK_MAX)) {
 		ret = -EINVAL;
 		goto out;
 	}

drivers/staging/iio/adc/spear_adc.c +2 -2

 	if (ret < 0) {
 		dev_err(dev, "failed requesting interrupt\n");
 		goto errout3;

@@ -370,7 +369,7 @@ static int spear_adc_probe(struct platform_device *pdev)
 
 	init_completion(&info->completion);
 
-	iodev->name = MOD_NAME;
+	iodev->name = SPEAR_ADC_MOD_NAME;
 	iodev->dev.parent = dev;
 	iodev->info = &spear_adc_iio_info;
 	iodev->modes = INDIO_DIRECT_MODE;

@@ -419,7 +418,7 @@ 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),
 	},

Quoted 151 lines · Jonathan Cameron

Signed-off-by Jonathan Cameron <[email protected]>

Acked-by Stefan Roese <[email protected]>

---
  drivers/staging/iio/adc/spear_adc.c | 73 ++++++++++++++++++-------------------
  1 file changed, 36 insertions(+), 37 deletions(-)

drivers/staging/iio/adc/spear_adc.c +32 -34

index 970d9ed..9234e05 100644
@@ -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 {

@@ -66,8 +63,8 @@ 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;

@@ -106,7 +103,7 @@ static void spear_adc_set_clk(struct spear_adc_info *info, u32 val)
  	clk_high = count - clk_low;
  	info->current_clk = apb_clk / count;
 
-	__raw_writel(CLK_LOW(clk_low) | CLK_HIGH(clk_high),
+	__raw_writel(SPEAR_ADC_CLK_LOW(clk_low) | SPEAR_ADC_CLK_HIGH(clk_high),
  		     &info->adc_base_spear6xx->clk);
  }
 

@@ -120,19 +117,19 @@ static u32 spear_adc_get_average(struct spear_adc_info *info)
  {
  	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
  		return __raw_readl(&info->adc_base_spear6xx->average.msb) &
-			DATA_MASK;
+			SPEAR_ADC_DATA_MASK;
  	} else {
  		return __raw_readl(&info->adc_base_spear3xx->average) &
-			DATA_MASK;
+			SPEAR_ADC_DATA_MASK;
  	}
  }
 
  static void spear_adc_set_scanrate(struct spear_adc_info *info, u32 rate)
  {
  	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
-		__raw_writel(SCAN_RATE_LO(rate),
+		__raw_writel(SPEAR600_ADC_SCAN_RATE_LO(rate),
  			     &info->adc_base_spear6xx->scan_rate_lo);
-		__raw_writel(SCAN_RATE_HI(rate),
+		__raw_writel(SPEAR600_ADC_SCAN_RATE_HI(rate),
  			     &info->adc_base_spear6xx->scan_rate_hi);
  	} else {
  		__raw_writel(rate, &info->adc_base_spear3xx->scan_rate);

@@ -152,11 +149,12 @@ static int spear_read_raw(struct iio_dev *indio_dev,
  	case IIO_CHAN_INFO_RAW:
  		mutex_lock(&indio_dev->mlock);
 
-		status = CHANNEL_NUM(chan->channel) |
-			AVG_SAMPLE(info->avg_samples) |
-			START_CONVERSION | ADC_ENABLE;
+		status = SPEAR_ADC_STATUS_CHANNEL_NUM(chan->channel) |
+			SPEAR_ADC_STATUS_AVG_SAMPLE(info->avg_samples) |
+			SPEAR_ADC_STATUS_START_CONVERSION |
+			SPEAR_ADC_STATUS_ADC_ENABLE;
  		if (info->vref_external == 0)
-			status |= VREF_INTERNAL;
+			status |= SPEAR_ADC_STATUS_VREF_INTERNAL;
 
  		spear_adc_set_status(info, status);
  		wait_for_completion(&info->completion); /* set by ISR */

@@ -168,7 +166,7 @@ static int spear_read_raw(struct iio_dev *indio_dev,
 
  	case IIO_CHAN_INFO_SCALE:
  		*val = info->vref_external;
-		*val2 = DATA_BITS;
+		*val2 = SPEAR_ADC_DATA_BITS;
  		return IIO_VAL_FRACTIONAL_LOG2;
  	}
 

@@ -253,7 +251,7 @@ static ssize_t spear_adc_write_frequency(struct device *dev,
 
  	mutex_lock(&indio_dev->mlock);
 
-	if ((lval < CLK_MIN) || (lval > CLK_MAX)) {
+	if ((lval < SPEAR_ADC_CLK_MIN) || (lval > SPEAR_ADC_CLK_MAX)) {
  		ret = -EINVAL;
  		goto out;
  	}

@@ -339,7 +337,8 @@ static int spear_adc_probe(struct platform_device *pdev)
  		goto errout3;
  	}
 

drivers/staging/iio/adc/spear_adc.c static int spear_adc_probe(struct platform_device *pdev) · line 341

Quoted 3 lines

drivers/staging/iio/adc/spear_adc.c +2 -1

-	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,
+			info);

Better indent with opening parenthesis.

Quoted 21 lines

drivers/staging/iio/adc/spear_adc.c +2 -2

  	if (ret < 0) {
  		dev_err(dev, "failed requesting interrupt\n");
  		goto errout3;

@@ -370,7 +369,7 @@ static int spear_adc_probe(struct platform_device *pdev)
 
  	init_completion(&info->completion);
 
-	iodev->name = MOD_NAME;
+	iodev->name = SPEAR_ADC_MOD_NAME;
  	iodev->dev.parent = dev;
  	iodev->info = &spear_adc_iio_info;
  	iodev->modes = INDIO_DIRECT_MODE;

@@ -419,7 +418,7 @@ 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),
  	},

Using the core support makes this element available to in kernel users as well as to userspace under exactly the same interface as before. The intent is to move all sampling frequency control to this approach throughout IIO.

Drop unused clk_high and clk_low whilst we are at it.

Signed-off-by Jonathan Cameron <[email protected]>

Acked-by Stefan Roese <[email protected]>

---
 drivers/staging/iio/adc/spear_adc.c | 96 ++++++++++++++-----------------------
 1 file changed, 37 insertions(+), 59 deletions(-)

drivers/staging/iio/adc/spear_adc.c +19 -0

index fa1e2b2..18a0a40 100644
@@ -168,16 +168,52 @@ static int spear_read_raw(struct iio_dev *indio_dev,
 		*val = info->vref_external;
 		*val2 = SPEAR_ADC_DATA_BITS;
 		return IIO_VAL_FRACTIONAL_LOG2;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val = info->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_info *info = iio_priv(indio_dev);
+	u32 count;
+	u32 apb_clk = clk_get_rate(info->clk);
+	int ret = 0;
+
+	if (mask != IIO_CHAN_INFO_SAMP_FREQ)
+		return -EINVAL;
+
+	mutex_lock(&indio_dev->mlock);
+

drivers/staging/iio/adc/spear_adc.c +8 -59

+
+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,					\
 }
 

@@ -219,67 +255,9 @@ static int spear_adc_configure(struct spear_adc_info *info)
 	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 < SPEAR_ADC_CLK_MIN) || (lval > SPEAR_ADC_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,
+	.write_raw = &spear_adc_write_raw,
 	.driver_module = THIS_MODULE,
 };
 

Quoted 52 lines · Jonathan Cameron

Using the core support makes this element available to in kernel users as well as to userspace under exactly the same interface as before. The intent is to move all sampling frequency control to this approach throughout IIO.

Drop unused clk_high and clk_low whilst we are at it.

Signed-off-by Jonathan Cameron <[email protected]>

Acked-by Stefan Roese <[email protected]>

---
  drivers/staging/iio/adc/spear_adc.c | 96 ++++++++++++++-----------------------
  1 file changed, 37 insertions(+), 59 deletions(-)

drivers/staging/iio/adc/spear_adc.c +26 -0

index fa1e2b2..18a0a40 100644
@@ -168,16 +168,52 @@ static int spear_read_raw(struct iio_dev *indio_dev,
  		*val = info->vref_external;
  		*val2 = SPEAR_ADC_DATA_BITS;
  		return IIO_VAL_FRACTIONAL_LOG2;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val = info->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_info *info = iio_priv(indio_dev);
+	u32 count;
+	u32 apb_clk = clk_get_rate(info->clk);
+	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;
+	}
+

drivers/staging/iio/adc/spear_adc.c static int spear_read_raw(struct iio_dev *indio_dev, · line 204

Quoted 3 lines

drivers/staging/iio/adc/spear_adc.c +3 -0

+	count = (apb_clk + val - 1) / val;
+	info->current_clk = apb_clk / count;
+	spear_adc_set_clk(info, val);

It's me again, same spot, but this time on caffeine and sugar ;-) This time I got curious about what spear_adc_set_clk actually does. And guess what (make sure to be seated): it does the same calculation of count and info->current_clk. So these two lines can leave, as well. My thoughts about that function will follow in patch 4.

Quoted 74 lines

drivers/staging/iio/adc/spear_adc.c +7 -55

+
+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,					\
  }
 

@@ -219,67 +255,9 @@ static int spear_adc_configure(struct spear_adc_info *info)
  	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 < SPEAR_ADC_CLK_MIN) || (lval > SPEAR_ADC_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 = {

drivers/staging/iio/adc/spear_adc.c static int spear_adc_configure(struct spear_adc_info *info) · line 263

Quoted 10 lines

drivers/staging/iio/adc/spear_adc.c +1 -4

-	.attrs = spear_attributes,
-};
-
  static const struct iio_info spear_adc_iio_info = {
  	.read_raw = &spear_read_raw,
-	.attrs = &spear_attribute_group,
+	.write_raw = &spear_adc_write_raw,
  	.driver_module = THIS_MODULE,
  };
 

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This simple driver is ready to move out of staging.

Signed-off-by Jonathan Cameron <[email protected]>

Acked-by Stefan Roese <[email protected]>

---
 drivers/iio/adc/Kconfig             |   8 +
 drivers/iio/adc/Makefile            |   1 +
 drivers/iio/adc/spear_adc.c         | 405 ++++++++++++++++++++++++++++++++++++
 drivers/staging/iio/adc/Kconfig     |   8 -
 drivers/staging/iio/adc/Makefile    |   1 -
 drivers/staging/iio/adc/spear_adc.c | 405 ------------------------------------
 6 files changed, 414 insertions(+), 414 deletions(-)

drivers/iio/adc/Kconfig +8 -0

index 5553206..2e3e1b0 100644
@@ -164,6 +164,14 @@ config NAU7802
 	  To compile this driver as a module, choose M here: the
 	  module will be called nau7802.
 
+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.
+
 config TI_ADC081C
 	tristate "Texas Instruments ADC081C021/027"
 	depends on I2C

drivers/iio/adc/Makefile +1 -0

index 89f1216..8378fb2 100644
@@ -18,6 +18,7 @@ obj-$(CONFIG_MAX1363) += max1363.o
 obj-$(CONFIG_MCP320X) += mcp320x.o
 obj-$(CONFIG_MCP3422) += mcp3422.o
 obj-$(CONFIG_NAU7802) += nau7802.o
+obj-$(CONFIG_SPEAR_ADC) += spear_adc.o
 obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
 obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
 obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o

drivers/iio/adc/spear_adc.c new file +0 -0

new file mode 100644
index 0000000..18a0a40

drivers/iio/adc/spear_adc.c new file +32 -0

+ *
+ * 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	(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)

drivers/iio/adc/spear_adc.c new file +29 -0

+
+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_info {
+	struct device_node *np;
+	struct adc_regs_spear3xx __iomem *adc_base_spear3xx;

drivers/iio/adc/spear_adc.c new file +7 -0

+	} else {
+		return __raw_readl(&info->adc_base_spear3xx->average) &
+			SPEAR_ADC_DATA_MASK;
+	}
+}
+
+static void spear_adc_set_scanrate(struct spear_adc_info *info, u32 rate)

drivers/iio/adc/spear_adc.c new file +21 -0

+
+static int spear_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);
+	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(info->avg_samples) |
+			SPEAR_ADC_STATUS_START_CONVERSION |
+			SPEAR_ADC_STATUS_ADC_ENABLE;
+		if (info->vref_external == 0)
+			status |= SPEAR_ADC_STATUS_VREF_INTERNAL;
+

drivers/iio/adc/spear_adc.c new file +6 -0

+}
+
+static int spear_adc_write_raw(struct iio_dev *indio_dev,
+			       struct iio_chan_spec const *chan,
+			       int val,
+			       int val2,

drivers/iio/adc/spear_adc.c new file +30 -0

+
+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_info *info = (struct spear_adc_info *)dev_id;
+

drivers/iio/adc/spear_adc.c new file +88 -0

+	int ret = -ENODEV;
+	int irq;
+
+	iodev = devm_iio_device_alloc(dev, sizeof(struct spear_adc_info));
+	if (!iodev) {
+		dev_err(dev, "failed allocating iio device\n");
+		return -ENOMEM;
+	}
+
+	info = iio_priv(iodev);
+	info->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) {
+		dev_err(dev, "failed mapping memory\n");
+		return -ENOMEM;
+	}
+	info->adc_base_spear3xx =
+		(struct adc_regs_spear3xx __iomem *)info->adc_base_spear6xx;
+
+	info->clk = clk_get(dev, NULL);
+	if (IS_ERR(info->clk)) {
+		dev_err(dev, "failed getting clock\n");
+		goto errout1;
+	}
+
+	ret = clk_prepare_enable(info->clk);
+	if (ret) {
+		dev_err(dev, "failed enabling clock\n");
+		goto errout2;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq <= 0) {
+		dev_err(dev, "failed getting interrupt resource\n");
+		ret = -EINVAL;
+		goto errout3;
+	}
+
+	ret = devm_request_irq(dev, irq, spear_adc_isr, 0, SPEAR_ADC_MOD_NAME,
+			info);
+	if (ret < 0) {
+		dev_err(dev, "failed requesting interrupt\n");
+		goto errout3;
+	}
+
+	if (of_property_read_u32(np, "sampling-frequency",
+				 &info->sampling_freq)) {
+		dev_err(dev, "sampling-frequency missing in DT\n");
+		ret = -EINVAL;
+		goto errout3;
+	}
+
+	/*
+	 * Optional avg_samples defaults to 0, resulting in single data
+	 * conversion
+	 */
+	of_property_read_u32(np, "average-samples", &info->avg_samples);
+
+	/*
+	 * Optional vref_external defaults to 0, resulting in internal vref
+	 * selection
+	 */
+	of_property_read_u32(np, "vref-external", &info->vref_external);
+
+	spear_adc_configure(info);
+
+	platform_set_drvdata(pdev, iodev);
+
+	init_completion(&info->completion);
+
+	iodev->name = SPEAR_ADC_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);
+
+	ret = iio_device_register(iodev);
+	if (ret)
+		goto errout3;
+
+	dev_info(dev, "SPEAR ADC driver loaded, IRQ %d\n", irq);

drivers/iio/adc/spear_adc.c new file +20 -0

+}
+
+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);
+
+	iio_device_unregister(iodev);
+	clk_disable_unprepare(info->clk);
+	clk_put(info->clk);
+	iounmap(info->adc_base_spear6xx);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id spear_adc_dt_ids[] = {
+	{ .compatible = "st,spear600-adc", },
+	{ /* sentinel */ }
+};

drivers/iio/adc/spear_adc.c new file +8 -0

+	},
+};
+
+module_platform_driver(spear_adc_driver);
+
+MODULE_AUTHOR("Stefan Roese <[email protected]>");
+MODULE_DESCRIPTION("SPEAr ADC driver");
+MODULE_LICENSE("GPL");

drivers/staging/iio/adc/Kconfig +0 -8

index 3633298..a37d001 100644
@@ -126,12 +126,4 @@ config MXS_LRADC
 	  To compile this driver as a module, choose M here: the
 	  module will be called mxs-lradc.
 
-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.
-
 endmenu

drivers/staging/iio/adc/Makefile +0 -1

index 3e9fb14..b5915c1 100644
@@ -19,4 +19,3 @@ obj-$(CONFIG_AD7192) += ad7192.o
 obj-$(CONFIG_AD7280) += ad7280a.o
 obj-$(CONFIG_LPC32XX_ADC) += lpc32xx_adc.o
 obj-$(CONFIG_MXS_LRADC) += mxs-lradc.o
-obj-$(CONFIG_SPEAR_ADC) += spear_adc.o

drivers/staging/iio/adc/spear_adc.c deleted +0 -405

deleted file mode 100644
index 18a0a40..0000000
@@ -1,405 +0,0 @@
-/*
- * ST SPEAr ADC driver
- *
- * Copyright 2012 Stefan Roese <[email protected]>
- *
- * 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	(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 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_info {
-	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_info *info, u32 val)
-{
-	__raw_writel(val, &info->adc_base_spear6xx->status);
-}
-
-static void spear_adc_set_clk(struct spear_adc_info *info, u32 val)
-{
-	u32 clk_high, clk_low, count;
-	u32 apb_clk = clk_get_rate(info->clk);
-
-	count = (apb_clk + val - 1) / val;
-	clk_low = count / 2;
-	clk_high = count - clk_low;
-	info->current_clk = apb_clk / count;
-
-	__raw_writel(SPEAR_ADC_CLK_LOW(clk_low) | SPEAR_ADC_CLK_HIGH(clk_high),
-		     &info->adc_base_spear6xx->clk);
-}
-
-static void spear_adc_set_ctrl(struct spear_adc_info *info, int n,
-			       u32 val)
-{
-	__raw_writel(val, &info->adc_base_spear6xx->ch_ctrl[n]);
-}
-
-static u32 spear_adc_get_average(struct spear_adc_info *info)
-{
-	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
-		return __raw_readl(&info->adc_base_spear6xx->average.msb) &
-			SPEAR_ADC_DATA_MASK;
-	} else {
-		return __raw_readl(&info->adc_base_spear3xx->average) &
-			SPEAR_ADC_DATA_MASK;
-	}
-}
-
-static void spear_adc_set_scanrate(struct spear_adc_info *info, u32 rate)
-{
-	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
-		__raw_writel(SPEAR600_ADC_SCAN_RATE_LO(rate),
-			     &info->adc_base_spear6xx->scan_rate_lo);
-		__raw_writel(SPEAR600_ADC_SCAN_RATE_HI(rate),
-			     &info->adc_base_spear6xx->scan_rate_hi);
-	} else {
-		__raw_writel(rate, &info->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)
-{
-	struct spear_adc_info *info = 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(info->avg_samples) |
-			SPEAR_ADC_STATUS_START_CONVERSION |
-			SPEAR_ADC_STATUS_ADC_ENABLE;
-		if (info->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;
-
-		mutex_unlock(&indio_dev->mlock);
-
-		return IIO_VAL_INT;
-
-	case IIO_CHAN_INFO_SCALE:
-		*val = info->vref_external;
-		*val2 = SPEAR_ADC_DATA_BITS;
-		return IIO_VAL_FRACTIONAL_LOG2;
-	case IIO_CHAN_INFO_SAMP_FREQ:
-		*val = info->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_info *info = iio_priv(indio_dev);
-	u32 count;
-	u32 apb_clk = clk_get_rate(info->clk);
-	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;
-	}
-
-	count = (apb_clk + val - 1) / val;
-	info->current_clk = apb_clk / count;
-	spear_adc_set_clk(info, 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_info *info = (struct spear_adc_info *)dev_id;
-
-	/* Read value to clear IRQ */
-	info->value = spear_adc_get_average(info);
-	complete(&info->completion);
-
-	return IRQ_HANDLED;
-}
-
-static int spear_adc_configure(struct spear_adc_info *info)
-{
-	int i;
-
-	/* Reset ADC core */
-	spear_adc_set_status(info, 0);
-	__raw_writel(0, &info->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_clk(info, info->sampling_freq);
-
-	return 0;
-}
-
-static const struct iio_info spear_adc_iio_info = {
-	.read_raw = &spear_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_info *info;
-	struct iio_dev *iodev = NULL;
-	int ret = -ENODEV;
-	int irq;
-
-	iodev = devm_iio_device_alloc(dev, sizeof(struct spear_adc_info));
-	if (!iodev) {
-		dev_err(dev, "failed allocating iio device\n");
-		return -ENOMEM;
-	}
-
-	info = iio_priv(iodev);
-	info->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) {
-		dev_err(dev, "failed mapping memory\n");
-		return -ENOMEM;
-	}
-	info->adc_base_spear3xx =
-		(struct adc_regs_spear3xx __iomem *)info->adc_base_spear6xx;
-
-	info->clk = clk_get(dev, NULL);
-	if (IS_ERR(info->clk)) {
-		dev_err(dev, "failed getting clock\n");
-		goto errout1;
-	}
-
-	ret = clk_prepare_enable(info->clk);
-	if (ret) {
-		dev_err(dev, "failed enabling clock\n");
-		goto errout2;
-	}
-
-	irq = platform_get_irq(pdev, 0);
-	if (irq <= 0) {
-		dev_err(dev, "failed getting interrupt resource\n");
-		ret = -EINVAL;
-		goto errout3;
-	}
-
-	ret = devm_request_irq(dev, irq, spear_adc_isr, 0, SPEAR_ADC_MOD_NAME,
-			info);
-	if (ret < 0) {
-		dev_err(dev, "failed requesting interrupt\n");
-		goto errout3;
-	}
-
-	if (of_property_read_u32(np, "sampling-frequency",
-				 &info->sampling_freq)) {
-		dev_err(dev, "sampling-frequency missing in DT\n");
-		ret = -EINVAL;
-		goto errout3;
-	}
-
-	/*
-	 * Optional avg_samples defaults to 0, resulting in single data
-	 * conversion
-	 */
-	of_property_read_u32(np, "average-samples", &info->avg_samples);
-
-	/*
-	 * Optional vref_external defaults to 0, resulting in internal vref
-	 * selection
-	 */
-	of_property_read_u32(np, "vref-external", &info->vref_external);
-
-	spear_adc_configure(info);
-
-	platform_set_drvdata(pdev, iodev);
-
-	init_completion(&info->completion);
-
-	iodev->name = SPEAR_ADC_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);
-
-	ret = iio_device_register(iodev);
-	if (ret)
-		goto errout3;
-
-	dev_info(dev, "SPEAR ADC driver loaded, IRQ %d\n", irq);
-
-	return 0;
-
-errout3:
-	clk_disable_unprepare(info->clk);
-errout2:
-	clk_put(info->clk);
-errout1:
-	iounmap(info->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);
-
-	iio_device_unregister(iodev);
-	clk_disable_unprepare(info->clk);
-	clk_put(info->clk);
-	iounmap(info->adc_base_spear6xx);
-
-	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,
-		.owner	= THIS_MODULE,
-		.of_match_table = of_match_ptr(spear_adc_dt_ids),
-	},
-};
-
-module_platform_driver(spear_adc_driver);
-
-MODULE_AUTHOR("Stefan Roese <[email protected]>");
-MODULE_DESCRIPTION("SPEAr ADC driver");
-MODULE_LICENSE("GPL");

Quoted 4 lines · Jonathan Cameron

This simple driver is ready to move out of staging.

Signed-off-by Jonathan Cameron <[email protected]>

Acked-by Stefan Roese <[email protected]>

Quoted 9 lines

---
  drivers/iio/adc/Kconfig             |   8 +
  drivers/iio/adc/Makefile            |   1 +
  drivers/iio/adc/spear_adc.c         | 405 ++++++++++++++++++++++++++++++++++++
  drivers/staging/iio/adc/Kconfig     |   8 -
  drivers/staging/iio/adc/Makefile    |   1 -
  drivers/staging/iio/adc/spear_adc.c | 405 ------------------------------------
  6 files changed, 414 insertions(+), 414 deletions(-)

drivers/iio/adc/Kconfig config NAU7802 · line 164

Quoted 6 lines

drivers/iio/adc/Kconfig +0 -0

index 5553206..2e3e1b0 100644
@@ -164,6 +164,14 @@ config NAU7802
  	  To compile this driver as a module, choose M here: the

Quoted 27 lines

drivers/iio/adc/Kconfig +8 -0

+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.
+
  config TI_ADC081C
  	tristate "Texas Instruments ADC081C021/027"
  	depends on I2C

drivers/iio/adc/Makefile +1 -0

index 89f1216..8378fb2 100644
@@ -18,6 +18,7 @@ obj-$(CONFIG_MAX1363) += max1363.o
  obj-$(CONFIG_MCP320X) += mcp320x.o
  obj-$(CONFIG_MCP3422) += mcp3422.o
  obj-$(CONFIG_NAU7802) += nau7802.o
+obj-$(CONFIG_SPEAR_ADC) += spear_adc.o
  obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
  obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
  obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o

drivers/iio/adc/spear_adc.c new file +0 -0

new file mode 100644
index 0000000..18a0a40

drivers/iio/adc/spear_adc.c line 4

Quoted 7 lines

drivers/iio/adc/spear_adc.c new file +4 -0

@@ -0,0 +1,405 @@
+/*
+ * ST SPEAr ADC driver
+ *
+ * Copyright 2012 Stefan Roese <[email protected]>

I found a datasheet at http://www.st.com/st-web-ui/static/active/en/resource/technical/document/reference_manual/DM00034813.pdf

ADC is covered on pages 594ff.

Quoted 35 lines

drivers/iio/adc/spear_adc.c new file +35 -0

+ *
+ * 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	(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 SPEAR_ADC_DATA_MASK		0x03ff
+#define SPEAR_ADC_DATA_BITS		10

drivers/iio/adc/spear_adc.c line 46

Quoted 7 lines

drivers/iio/adc/spear_adc.c new file +7 -0

+
+#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

Datasheet page 599: "The max frequency of CLK_ADC is 14 MHz as the minimum is 3 MHz"

Quoted 32 lines

drivers/iio/adc/spear_adc.c new file +32 -0

+
+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_info {
+	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;

drivers/iio/adc/spear_adc.c line 85

Quoted 7 lines

drivers/iio/adc/spear_adc.c new file +7 -0

+	u32 current_clk;
+	u32 sampling_freq;
+	u32 avg_samples;
+	u32 vref_external;
+	u32 value;
+};
+

I would prefer to see some comments like in other drivers, to get an idea what units are assumed (especially for vref_external).

Also, I would rename it to the scheme, that the majority of the drivers seem to use: struct spear_adc_state (and the instances *st instead of *info).

drivers/iio/adc/spear_adc.c line 94

Quoted 9 lines

drivers/iio/adc/spear_adc.c new file +9 -0

+/*
+ * 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_info *info, u32 val)
+{
+	__raw_writel(val, &info->adc_base_spear6xx->status);
+}

Datasheet page 597 says: "It can be written only if both values ADC_STATUS_REG [8] and ADC_STATUS_REG [0] are ‘0’."

This can be a problem, since bit 0 gets set by spear_read_raw().

drivers/iio/adc/spear_adc.c line 105

Quoted 11 lines

drivers/iio/adc/spear_adc.c new file +11 -0

+
+static void spear_adc_set_clk(struct spear_adc_info *info, u32 val)
+{
+	u32 clk_high, clk_low, count;
+	u32 apb_clk = clk_get_rate(info->clk);
+
+	count = (apb_clk + val - 1) / val;
+	clk_low = count / 2;
+	clk_high = count - clk_low;
+	info->current_clk = apb_clk / count;
+

I've got some doubts about this calculation. The datasheet say on page 599: "...the [adc-]frequency is the APB clock frequency divided by the sum of these values[clk_low and clk_high].". So I would represent it as following:

val = apb_clk / (clk_low + clk_high) = apb_clk / count

So, first thing we want is count, so multiply by count and divide by val:

count = apb_clk / val

The rest seems fine, but it should be kept in mind, that clk_low and clk_high are just 4 bit size, each. So, using u8 would be sufficient (also for count), and clk_low and clk_high should be checked to not exceed a value of 0xF (or count for 0x1F). Thus, changing the function type to int would also help to return an error code.

drivers/iio/adc/spear_adc.c line 115

Quoted 10 lines

drivers/iio/adc/spear_adc.c new file +10 -0

+	__raw_writel(SPEAR_ADC_CLK_LOW(clk_low) | SPEAR_ADC_CLK_HIGH(clk_high),
+		     &info->adc_base_spear6xx->clk);
+}
+
+static void spear_adc_set_ctrl(struct spear_adc_info *info, int n,
+			       u32 val)
+{
+	__raw_writel(val, &info->adc_base_spear6xx->ch_ctrl[n]);
+}
+

Datasheet page 599 says: "It is possible to write these registers only if ENABLE is ‘0’."
Although spear_adc_configure() takes care of that under the current circumstances, it might cause some troubles in case someone makes use of this function any time later. So either check for it here, or leave a comment.

drivers/iio/adc/spear_adc.c line 120

Quoted 5 lines

drivers/iio/adc/spear_adc.c new file +5 -0

+static u32 spear_adc_get_average(struct spear_adc_info *info)
+{
+	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
+		return __raw_readl(&info->adc_base_spear6xx->average.msb) &
+			SPEAR_ADC_DATA_MASK;

Datasheet page 601 says: "The AVERAGE_REG_MSB register has latched the word of the conversion ant it can be read only if both values CONVERSION READY and ENABLE are ‘1’." Page 595 says: "At the end of conversion, the CONVERSION READY bit in ADC_STATUS_REG is set and an interrupt signal is generated."
So, since this function is only called during interrupt-handling, it is fine. But maybe also add a comment.

Quoted 10 lines

drivers/iio/adc/spear_adc.c new file +10 -0

+	} else {
+		return __raw_readl(&info->adc_base_spear3xx->average) &
+			SPEAR_ADC_DATA_MASK;
+	}
+}
+
+static void spear_adc_set_scanrate(struct spear_adc_info *info, u32 rate)
+{
+	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
+		__raw_writel(SPEAR600_ADC_SCAN_RATE_LO(rate),

drivers/iio/adc/spear_adc.c line 137

Quoted 7 lines

drivers/iio/adc/spear_adc.c new file +7 -0

+			     &info->adc_base_spear6xx->scan_rate_lo);
+		__raw_writel(SPEAR600_ADC_SCAN_RATE_HI(rate),
+			     &info->adc_base_spear6xx->scan_rate_hi);
+	} else {
+		__raw_writel(rate, &info->adc_base_spear3xx->scan_rate);
+	}
+}

Datasheet page 600/601: "This register can be written only if both values ADC_STATUS_REG [8] and ADC_STATUS_REG [0] are ‘0’." Same as above, a comment would be good.

Quoted 24 lines

drivers/iio/adc/spear_adc.c new file +24 -0

+
+static int spear_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);
+	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(info->avg_samples) |
+			SPEAR_ADC_STATUS_START_CONVERSION |
+			SPEAR_ADC_STATUS_ADC_ENABLE;
+		if (info->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;

drivers/iio/adc/spear_adc.c line 168

Quoted 7 lines

drivers/iio/adc/spear_adc.c new file +7 -0

+
+		mutex_unlock(&indio_dev->mlock);
+
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SCALE:
+		*val = info->vref_external;

What if internal reference is selected?

In my opinion, this driver should also be converted to use regulator framework (the boards will certainly contain some regulator, anyway).

drivers/iio/adc/spear_adc.c line 176

Quoted 8 lines

drivers/iio/adc/spear_adc.c new file +8 -0

+		*val2 = SPEAR_ADC_DATA_BITS;
+		return IIO_VAL_FRACTIONAL_LOG2;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val = info->current_clk;
+		return IIO_VAL_INT;
+	}
+
+	return -EINVAL;

Catch invalid masks with default: section?

Quoted 9 lines

drivers/iio/adc/spear_adc.c new file +9 -0

+}
+
+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_info *info = iio_priv(indio_dev);

drivers/iio/adc/spear_adc.c line 192

Quoted 7 lines

drivers/iio/adc/spear_adc.c new file +7 -0

+	u32 count;
+	u32 apb_clk = clk_get_rate(info->clk);
+	int ret = 0;
+
+	if (mask != IIO_CHAN_INFO_SAMP_FREQ)
+		return -EINVAL;
+

IMHO using switch(mask) like in the read_raw functions would be more beautiful (though at the cost of a deeper indent level), yet this also does the job.

drivers/iio/adc/spear_adc.c line 196

Quoted 4 lines

drivers/iio/adc/spear_adc.c new file +4 -0

+	mutex_lock(&indio_dev->mlock);
+
+	if ((val < SPEAR_ADC_CLK_MIN) ||
+		(val > SPEAR_ADC_CLK_MAX) ||

As mentioned above, I don't know if these values are accurate, or if it would even make more sense to just check that clk_low and clk_high fit into 4 bits, each.

drivers/iio/adc/spear_adc.c line 204

Quoted 8 lines

drivers/iio/adc/spear_adc.c new file +8 -0

+		(val2 != 0)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	count = (apb_clk + val - 1) / val;
+	info->current_clk = apb_clk / count;
+	spear_adc_set_clk(info, val);

As mentioned in the previous patch, get rid of count and apb_clk here.

Quoted 33 lines

drivers/iio/adc/spear_adc.c new file +33 -0

+
+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_info *info = (struct spear_adc_info *)dev_id;
+
+	/* Read value to clear IRQ */
+	info->value = spear_adc_get_average(info);
+	complete(&info->completion);

drivers/iio/adc/spear_adc.c line 244

Quoted 7 lines

drivers/iio/adc/spear_adc.c new file +7 -0

+
+	return IRQ_HANDLED;
+}
+
+static int spear_adc_configure(struct spear_adc_info *info)
+{
+	int i;

u8 i; would also do the job.

drivers/iio/adc/spear_adc.c line 249

Quoted 5 lines

drivers/iio/adc/spear_adc.c new file +5 -0

+
+	/* Reset ADC core */
+	spear_adc_set_status(info, 0);
+	__raw_writel(0, &info->adc_base_spear6xx->clk);
+	for (i = 0; i < 8; i++)

i < ARRAY_SIZE or i < ADC_CHANNEL_NUM to prevent buffer overflows.

drivers/iio/adc/spear_adc.c line 260

Quoted 11 lines

drivers/iio/adc/spear_adc.c new file +11 -0

+		spear_adc_set_ctrl(info, i, 0);
+	spear_adc_set_scanrate(info, 0);
+
+	spear_adc_set_clk(info, info->sampling_freq);
+
+	return 0;
+}
+
+static const struct iio_info spear_adc_iio_info = {
+	.read_raw = &spear_read_raw,
+	.write_raw = &spear_adc_write_raw,

Better use the same prefix for those functions (also rename one of them, above).

drivers/iio/adc/spear_adc.c line 269

Quoted 9 lines

drivers/iio/adc/spear_adc.c new file +9 -0

+	.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_info *info;
+	struct iio_dev *iodev = NULL;

Not really wrong, but nobody does that these days anymore. And we normally call it indio_dev

Quoted 91 lines

drivers/iio/adc/spear_adc.c new file +91 -0

+	int ret = -ENODEV;
+	int irq;
+
+	iodev = devm_iio_device_alloc(dev, sizeof(struct spear_adc_info));
+	if (!iodev) {
+		dev_err(dev, "failed allocating iio device\n");
+		return -ENOMEM;
+	}
+
+	info = iio_priv(iodev);
+	info->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) {
+		dev_err(dev, "failed mapping memory\n");
+		return -ENOMEM;
+	}
+	info->adc_base_spear3xx =
+		(struct adc_regs_spear3xx __iomem *)info->adc_base_spear6xx;
+
+	info->clk = clk_get(dev, NULL);
+	if (IS_ERR(info->clk)) {
+		dev_err(dev, "failed getting clock\n");
+		goto errout1;
+	}
+
+	ret = clk_prepare_enable(info->clk);
+	if (ret) {
+		dev_err(dev, "failed enabling clock\n");
+		goto errout2;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq <= 0) {
+		dev_err(dev, "failed getting interrupt resource\n");
+		ret = -EINVAL;
+		goto errout3;
+	}
+
+	ret = devm_request_irq(dev, irq, spear_adc_isr, 0, SPEAR_ADC_MOD_NAME,
+			info);
+	if (ret < 0) {
+		dev_err(dev, "failed requesting interrupt\n");
+		goto errout3;
+	}
+
+	if (of_property_read_u32(np, "sampling-frequency",
+				 &info->sampling_freq)) {
+		dev_err(dev, "sampling-frequency missing in DT\n");
+		ret = -EINVAL;
+		goto errout3;
+	}
+
+	/*
+	 * Optional avg_samples defaults to 0, resulting in single data
+	 * conversion
+	 */
+	of_property_read_u32(np, "average-samples", &info->avg_samples);
+
+	/*
+	 * Optional vref_external defaults to 0, resulting in internal vref
+	 * selection
+	 */
+	of_property_read_u32(np, "vref-external", &info->vref_external);
+
+	spear_adc_configure(info);
+
+	platform_set_drvdata(pdev, iodev);
+
+	init_completion(&info->completion);
+
+	iodev->name = SPEAR_ADC_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);
+
+	ret = iio_device_register(iodev);
+	if (ret)
+		goto errout3;
+
+	dev_info(dev, "SPEAR ADC driver loaded, IRQ %d\n", irq);
+
+	return 0;
+

drivers/iio/adc/spear_adc.c line 367

Quoted 7 lines

drivers/iio/adc/spear_adc.c new file +7 -0

+errout3:
+	clk_disable_unprepare(info->clk);
+errout2:
+	clk_put(info->clk);
+errout1:
+	iounmap(info->adc_base_spear6xx);
+	return ret;

These labels could have more appropriate names.

Quoted 23 lines

drivers/iio/adc/spear_adc.c new file +23 -0

+}
+
+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);
+
+	iio_device_unregister(iodev);
+	clk_disable_unprepare(info->clk);
+	clk_put(info->clk);
+	iounmap(info->adc_base_spear6xx);
+
+	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
+

drivers/iio/adc/spear_adc.c line 397

Quoted 7 lines

drivers/iio/adc/spear_adc.c new file +7 -0

+static struct platform_driver spear_adc_driver = {
+	.probe		= spear_adc_probe,
+	.remove		= spear_adc_remove,
+	.driver		= {
+		.name	= SPEAR_ADC_MOD_NAME,
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(spear_adc_dt_ids),

What if CONFIG_OF is disabled?

Quoted 435 lines

drivers/iio/adc/spear_adc.c new file +8 -0

+	},
+};
+
+module_platform_driver(spear_adc_driver);
+
+MODULE_AUTHOR("Stefan Roese <[email protected]>");
+MODULE_DESCRIPTION("SPEAr ADC driver");
+MODULE_LICENSE("GPL");

drivers/staging/iio/adc/Kconfig +0 -8

index 3633298..a37d001 100644
@@ -126,12 +126,4 @@ config MXS_LRADC
  	  To compile this driver as a module, choose M here: the
  	  module will be called mxs-lradc.
 
-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.
-
  endmenu

drivers/staging/iio/adc/Makefile +0 -1

index 3e9fb14..b5915c1 100644
@@ -19,4 +19,3 @@ obj-$(CONFIG_AD7192) += ad7192.o
  obj-$(CONFIG_AD7280) += ad7280a.o
  obj-$(CONFIG_LPC32XX_ADC) += lpc32xx_adc.o
  obj-$(CONFIG_MXS_LRADC) += mxs-lradc.o
-obj-$(CONFIG_SPEAR_ADC) += spear_adc.o

drivers/staging/iio/adc/spear_adc.c deleted +0 -395

deleted file mode 100644
index 18a0a40..0000000
@@ -1,405 +0,0 @@
-/*
- * ST SPEAr ADC driver
- *
- * Copyright 2012 Stefan Roese <[email protected]>
- *
- * 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	(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 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_info {
-	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_info *info, u32 val)
-{
-	__raw_writel(val, &info->adc_base_spear6xx->status);
-}
-
-static void spear_adc_set_clk(struct spear_adc_info *info, u32 val)
-{
-	u32 clk_high, clk_low, count;
-	u32 apb_clk = clk_get_rate(info->clk);
-
-	count = (apb_clk + val - 1) / val;
-	clk_low = count / 2;
-	clk_high = count - clk_low;
-	info->current_clk = apb_clk / count;
-
-	__raw_writel(SPEAR_ADC_CLK_LOW(clk_low) | SPEAR_ADC_CLK_HIGH(clk_high),
-		     &info->adc_base_spear6xx->clk);
-}
-
-static void spear_adc_set_ctrl(struct spear_adc_info *info, int n,
-			       u32 val)
-{
-	__raw_writel(val, &info->adc_base_spear6xx->ch_ctrl[n]);
-}
-
-static u32 spear_adc_get_average(struct spear_adc_info *info)
-{
-	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
-		return __raw_readl(&info->adc_base_spear6xx->average.msb) &
-			SPEAR_ADC_DATA_MASK;
-	} else {
-		return __raw_readl(&info->adc_base_spear3xx->average) &
-			SPEAR_ADC_DATA_MASK;
-	}
-}
-
-static void spear_adc_set_scanrate(struct spear_adc_info *info, u32 rate)
-{
-	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
-		__raw_writel(SPEAR600_ADC_SCAN_RATE_LO(rate),
-			     &info->adc_base_spear6xx->scan_rate_lo);
-		__raw_writel(SPEAR600_ADC_SCAN_RATE_HI(rate),
-			     &info->adc_base_spear6xx->scan_rate_hi);
-	} else {
-		__raw_writel(rate, &info->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)
-{
-	struct spear_adc_info *info = 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(info->avg_samples) |
-			SPEAR_ADC_STATUS_START_CONVERSION |
-			SPEAR_ADC_STATUS_ADC_ENABLE;
-		if (info->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;
-
-		mutex_unlock(&indio_dev->mlock);
-
-		return IIO_VAL_INT;
-
-	case IIO_CHAN_INFO_SCALE:
-		*val = info->vref_external;
-		*val2 = SPEAR_ADC_DATA_BITS;
-		return IIO_VAL_FRACTIONAL_LOG2;
-	case IIO_CHAN_INFO_SAMP_FREQ:
-		*val = info->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_info *info = iio_priv(indio_dev);
-	u32 count;
-	u32 apb_clk = clk_get_rate(info->clk);
-	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;
-	}
-
-	count = (apb_clk + val - 1) / val;
-	info->current_clk = apb_clk / count;
-	spear_adc_set_clk(info, 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_info *info = (struct spear_adc_info *)dev_id;
-
-	/* Read value to clear IRQ */
-	info->value = spear_adc_get_average(info);
-	complete(&info->completion);
-
-	return IRQ_HANDLED;
-}
-
-static int spear_adc_configure(struct spear_adc_info *info)
-{
-	int i;
-
-	/* Reset ADC core */
-	spear_adc_set_status(info, 0);
-	__raw_writel(0, &info->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_clk(info, info->sampling_freq);
-
-	return 0;
-}
-
-static const struct iio_info spear_adc_iio_info = {
-	.read_raw = &spear_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_info *info;
-	struct iio_dev *iodev = NULL;
-	int ret = -ENODEV;
-	int irq;
-
-	iodev = devm_iio_device_alloc(dev, sizeof(struct spear_adc_info));
-	if (!iodev) {
-		dev_err(dev, "failed allocating iio device\n");
-		return -ENOMEM;
-	}
-
-	info = iio_priv(iodev);
-	info->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) {
-		dev_err(dev, "failed mapping memory\n");
-		return -ENOMEM;
-	}
-	info->adc_base_spear3xx =
-		(struct adc_regs_spear3xx __iomem *)info->adc_base_spear6xx;
-
-	info->clk = clk_get(dev, NULL);
-	if (IS_ERR(info->clk)) {
-		dev_err(dev, "failed getting clock\n");
-		goto errout1;
-	}
-
-	ret = clk_prepare_enable(info->clk);
-	if (ret) {
-		dev_err(dev, "failed enabling clock\n");
-		goto errout2;
-	}
-
-	irq = platform_get_irq(pdev, 0);
-	if (irq <= 0) {
-		dev_err(dev, "failed getting interrupt resource\n");
-		ret = -EINVAL;
-		goto errout3;
-	}
-
-	ret = devm_request_irq(dev, irq, spear_adc_isr, 0, SPEAR_ADC_MOD_NAME,
-			info);
-	if (ret < 0) {
-		dev_err(dev, "failed requesting interrupt\n");
-		goto errout3;
-	}
-
-	if (of_property_read_u32(np, "sampling-frequency",
-				 &info->sampling_freq)) {
-		dev_err(dev, "sampling-frequency missing in DT\n");
-		ret = -EINVAL;
-		goto errout3;
-	}
-
-	/*
-	 * Optional avg_samples defaults to 0, resulting in single data
-	 * conversion
-	 */
-	of_property_read_u32(np, "average-samples", &info->avg_samples);
-
-	/*
-	 * Optional vref_external defaults to 0, resulting in internal vref
-	 * selection
-	 */
-	of_property_read_u32(np, "vref-external", &info->vref_external);
-
-	spear_adc_configure(info);
-
-	platform_set_drvdata(pdev, iodev);
-
-	init_completion(&info->completion);
-
-	iodev->name = SPEAR_ADC_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);
-
-	ret = iio_device_register(iodev);
-	if (ret)
-		goto errout3;
-
-	dev_info(dev, "SPEAR ADC driver loaded, IRQ %d\n", irq);
-
-	return 0;
-
-errout3:
-	clk_disable_unprepare(info->clk);
-errout2:
-	clk_put(info->clk);
-errout1:
-	iounmap(info->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);
-
-	iio_device_unregister(iodev);
-	clk_disable_unprepare(info->clk);
-	clk_put(info->clk);
-	iounmap(info->adc_base_spear6xx);
-
-	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,

drivers/staging/iio/adc/spear_adc.c line 405

Quoted 10 lines

drivers/staging/iio/adc/spear_adc.c deleted +0 -10

-		.owner	= THIS_MODULE,
-		.of_match_table = of_match_ptr(spear_adc_dt_ids),
-	},
-};
-
-module_platform_driver(spear_adc_driver);
-
-MODULE_AUTHOR("Stefan Roese <[email protected]>");
-MODULE_DESCRIPTION("SPEAr ADC driver");
-MODULE_LICENSE("GPL");

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Quoted 5 lines · Hartmut Knaack

Quoted 4 lines · Jonathan Cameron

This simple driver is ready to move out of staging.

Signed-off-by Jonathan Cameron <[email protected]>

Acked-by Stefan Roese <[email protected]>

Stefan, there are some 'what is going on?' questions in here you might want to answer!

Quoted 11 lines

Quoted 11 lines

---
  drivers/iio/adc/Kconfig             |   8 +
  drivers/iio/adc/Makefile            |   1 +
  drivers/iio/adc/spear_adc.c         | 405
++++++++++++++++++++++++++++++++++++
  drivers/staging/iio/adc/Kconfig     |   8 -
  drivers/staging/iio/adc/Makefile    |   1 -
  drivers/staging/iio/adc/spear_adc.c | 405
------------------------------------
  6 files changed, 414 insertions(+), 414 deletions(-)

Quoted 6 lines

drivers/iio/adc/Kconfig config NAU7802 · line 164

Quoted 6 lines

drivers/iio/adc/Kconfig +0 -0

index 5553206..2e3e1b0 100644
@@ -164,6 +164,14 @@ config NAU7802
        To compile this driver as a module, choose M here: the

s>> module will be called nau7802.

Quoted 28 lines

Quoted 28 lines

drivers/iio/adc/Kconfig +8 -0

+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.
+
  config TI_ADC081C
      tristate "Texas Instruments ADC081C021/027"
      depends on I2C

drivers/iio/adc/Makefile +1 -0

index 89f1216..8378fb2 100644
@@ -18,6 +18,7 @@ obj-$(CONFIG_MAX1363) += max1363.o
  obj-$(CONFIG_MCP320X) += mcp320x.o
  obj-$(CONFIG_MCP3422) += mcp3422.o
  obj-$(CONFIG_NAU7802) += nau7802.o
+obj-$(CONFIG_SPEAR_ADC) += spear_adc.o
  obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
  obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
  obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o

drivers/iio/adc/spear_adc.c new file +0 -1

new file mode 100644
index 0000000..18a0a40
--- /dev/null

Quoted 9 lines

drivers/iio/adc/spear_adc.c line 4

Quoted 6 lines

+++ b/drivers/iio/adc/spear_adc.c

drivers/iio/adc/spear_adc.c new file +4 -0

@@ -0,0 +1,405 @@
+/*
+ * ST SPEAr ADC driver
+ *
+ * Copyright 2012 Stefan Roese <[email protected]>

I found a datasheet at
http://www.st.com/st-web-ui/static/active/en/resource/technical/document/reference_manual/DM00034813.pdf

THis is one of a number I think.. Not sure which parts will work out of the box
with this driver though... Stefan? What was it written against?

Quoted 8 lines · Jonathan Cameron

Quoted 5 lines · Hartmut Knaack

Quoted 4 lines · Jonathan Cameron

This simple driver is ready to move out of staging.

Signed-off-by Jonathan Cameron <[email protected]>

Acked-by Stefan Roese <[email protected]>

Stefan, there are some 'what is going on?' questions in here you might want to answer!

I'll give it a try.

Quoted 56 lines

Quoted 11 lines

Quoted 11 lines

---
  drivers/iio/adc/Kconfig             |   8 +
  drivers/iio/adc/Makefile            |   1 +
  drivers/iio/adc/spear_adc.c         | 405
++++++++++++++++++++++++++++++++++++
  drivers/staging/iio/adc/Kconfig     |   8 -
  drivers/staging/iio/adc/Makefile    |   1 -
  drivers/staging/iio/adc/spear_adc.c | 405
------------------------------------
  6 files changed, 414 insertions(+), 414 deletions(-)

Quoted 6 lines

drivers/iio/adc/Kconfig config NAU7802 · line 164

Quoted 6 lines

drivers/iio/adc/Kconfig +0 -0

index 5553206..2e3e1b0 100644
@@ -164,6 +164,14 @@ config NAU7802
        To compile this driver as a module, choose M here: the

s>> module will be called nau7802.

Quoted 37 lines

Quoted 30 lines

drivers/iio/adc/Kconfig +8 -0

+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.
+
  config TI_ADC081C
      tristate "Texas Instruments ADC081C021/027"
      depends on I2C

drivers/iio/adc/Makefile +1 -0

index 89f1216..8378fb2 100644
@@ -18,6 +18,7 @@ obj-$(CONFIG_MAX1363) += max1363.o
  obj-$(CONFIG_MCP320X) += mcp320x.o
  obj-$(CONFIG_MCP3422) += mcp3422.o
  obj-$(CONFIG_NAU7802) += nau7802.o
+obj-$(CONFIG_SPEAR_ADC) += spear_adc.o
  obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
  obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
  obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o

drivers/iio/adc/spear_adc.c new file +0 -0

new file mode 100644
index 0000000..18a0a40

drivers/iio/adc/spear_adc.c line 4

Quoted 4 lines

drivers/iio/adc/spear_adc.c new file +4 -0

@@ -0,0 +1,405 @@
+/*
+ * ST SPEAr ADC driver
+ *
+ * Copyright 2012 Stefan Roese <[email protected]>

I found a datasheet at
http://www.st.com/st-web-ui/static/active/en/resource/technical/document/reference_manual/DM00034813.pdf

Quoted 3 lines

THis is one of a number I think.. Not sure which parts will work out of the box
with this driver though... Stefan? What was it written against?

I wrote and tested this driver for the SPEAr600 in 2011/2012. The manual mentioned above didn't exist at that time. I used one called "UM510_rev3.0.pdf" from Feb 2011. If interested I can send you the manual I used at that time.

I don't have access to the SPEAr600 hardware anymore. I'm afraid but I can't be of much help here.

Thanks,
Stefan

Quoted 65 lines · Stefan Roese

Quoted 8 lines · Jonathan Cameron

Quoted 5 lines · Hartmut Knaack

Quoted 4 lines · Jonathan Cameron

This simple driver is ready to move out of staging.

Signed-off-by Jonathan Cameron <[email protected]>

Acked-by Stefan Roese <[email protected]>

Stefan, there are some 'what is going on?' questions in here you might want to answer!

I'll give it a try.

Quoted 54 lines

Quoted 11 lines

Quoted 11 lines

---
  drivers/iio/adc/Kconfig             |   8 +
  drivers/iio/adc/Makefile            |   1 +
  drivers/iio/adc/spear_adc.c         | 405
++++++++++++++++++++++++++++++++++++
  drivers/staging/iio/adc/Kconfig     |   8 -
  drivers/staging/iio/adc/Makefile    |   1 -
  drivers/staging/iio/adc/spear_adc.c | 405
------------------------------------
  6 files changed, 414 insertions(+), 414 deletions(-)

Quoted 6 lines

drivers/iio/adc/Kconfig config NAU7802 · line 164

Quoted 6 lines

drivers/iio/adc/Kconfig +0 -0

index 5553206..2e3e1b0 100644
@@ -164,6 +164,14 @@ config NAU7802
        To compile this driver as a module, choose M here: the

s>> module will be called nau7802.

Quoted 36 lines

Quoted 29 lines

drivers/iio/adc/Kconfig +8 -0

+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.
+
  config TI_ADC081C
      tristate "Texas Instruments ADC081C021/027"
      depends on I2C

drivers/iio/adc/Makefile +1 -0

index 89f1216..8378fb2 100644
@@ -18,6 +18,7 @@ obj-$(CONFIG_MAX1363) += max1363.o
  obj-$(CONFIG_MCP320X) += mcp320x.o
  obj-$(CONFIG_MCP3422) += mcp3422.o
  obj-$(CONFIG_NAU7802) += nau7802.o
+obj-$(CONFIG_SPEAR_ADC) += spear_adc.o
  obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
  obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
  obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o

drivers/iio/adc/spear_adc.c new file +0 -0

new file mode 100644
index 0000000..18a0a40

drivers/iio/adc/spear_adc.c line 4

Quoted 4 lines

drivers/iio/adc/spear_adc.c new file +4 -0

@@ -0,0 +1,405 @@
+/*
+ * ST SPEAr ADC driver
+ *
+ * Copyright 2012 Stefan Roese <[email protected]>

I found a datasheet at
http://www.st.com/st-web-ui/static/active/en/resource/technical/document/reference_manual/DM00034813.pdf

Quoted 7 lines

Quoted 3 lines

THis is one of a number I think.. Not sure which parts will work out of the box
with this driver though... Stefan? What was it written against?

I wrote and tested this driver for the SPEAr600 in 2011/2012. The manual mentioned above didn't exist at that time. I used one called "UM510_rev3.0.pdf" from Feb 2011. If interested I can send you the manual I used at that time.

I don't have access to the SPEAr600 hardware anymore. I'm afraid but I can't be of much help here.

I'm tempted to say that, given it worked for stefan back then, we do what non functional clean ups make sense and push the driver out of staging whilst avoiding the issues highlighted by the 'interesting' datasheets.

Either that, or if someone else wants to take on getting clarifications from ST on how it actually works, that is fine by me.

J

Quoted 2 lines

Thanks,
Stefan

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Quoted 78 lines · Jonathan Cameron

Quoted 65 lines · Stefan Roese

Quoted 8 lines · Jonathan Cameron

Quoted 5 lines · Hartmut Knaack

Quoted 4 lines · Jonathan Cameron

This simple driver is ready to move out of staging.

Signed-off-by Jonathan Cameron <[email protected]>

Acked-by Stefan Roese <[email protected]>

Stefan, there are some 'what is going on?' questions in here you might want to answer!

I'll give it a try.

Quoted 54 lines

Quoted 11 lines

Quoted 11 lines

---
   drivers/iio/adc/Kconfig             |   8 +
   drivers/iio/adc/Makefile            |   1 +
   drivers/iio/adc/spear_adc.c         | 405
++++++++++++++++++++++++++++++++++++
   drivers/staging/iio/adc/Kconfig     |   8 -
   drivers/staging/iio/adc/Makefile    |   1 -
   drivers/staging/iio/adc/spear_adc.c | 405
------------------------------------
   6 files changed, 414 insertions(+), 414 deletions(-)

Quoted 6 lines

drivers/iio/adc/Kconfig config NAU7802 · line 164

Quoted 6 lines

drivers/iio/adc/Kconfig +0 -0

index 5553206..2e3e1b0 100644
@@ -164,6 +164,14 @@ config NAU7802
         To compile this driver as a module, choose M here: the

s>> module will be called nau7802.

Quoted 36 lines

Quoted 29 lines

drivers/iio/adc/Kconfig +8 -0

+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.
+
   config TI_ADC081C
       tristate "Texas Instruments ADC081C021/027"
       depends on I2C

drivers/iio/adc/Makefile +1 -0

index 89f1216..8378fb2 100644
@@ -18,6 +18,7 @@ obj-$(CONFIG_MAX1363) += max1363.o
   obj-$(CONFIG_MCP320X) += mcp320x.o
   obj-$(CONFIG_MCP3422) += mcp3422.o
   obj-$(CONFIG_NAU7802) += nau7802.o
+obj-$(CONFIG_SPEAR_ADC) += spear_adc.o
   obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
   obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
   obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o

drivers/iio/adc/spear_adc.c new file +0 -0

new file mode 100644
index 0000000..18a0a40

drivers/iio/adc/spear_adc.c line 4

Quoted 4 lines

drivers/iio/adc/spear_adc.c new file +4 -0

@@ -0,0 +1,405 @@
+/*
+ * ST SPEAr ADC driver
+ *
+ * Copyright 2012 Stefan Roese <[email protected]>

I found a datasheet at
http://www.st.com/st-web-ui/static/active/en/resource/technical/document/reference_manual/DM00034813.pdf

Quoted 7 lines

Quoted 3 lines

THis is one of a number I think.. Not sure which parts will work out of the box
with this driver though... Stefan? What was it written against?

I wrote and tested this driver for the SPEAr600 in 2011/2012. The manual mentioned above didn't exist at that time. I used one called "UM510_rev3.0.pdf" from Feb 2011. If interested I can send you the manual I used at that time.

I don't have access to the SPEAr600 hardware anymore. I'm afraid but I can't be of much help here.

I'm tempted to say that, given it worked for stefan back then, we do what non functional clean ups make sense and push the driver out of staging whilst avoiding the issues highlighted by the 'interesting' datasheets.

Quoted 5 lines

Either that, or if someone else wants to take on getting clarifications from ST on how it actually works, that is fine by me.

J

I would agree to fix the issues which obviously violate the datasheet (get rid of SPEAR_ADC_CLK_MIN/MAX, rework calculation of count in spear_adc_set_clk and check boundaries of clk_low and clk_high, make spear_read_raw aware of the currently selected reference voltage), and just place comments about required set/cleared bits on top of those functions, where the datasheet is confusing (spear_adc_set_status, spear_adc_set_ctrl, spear_adc_get_average, spear_adc_set_scanrate). Now, that I looked over it again, I would also propose to move the content of spear_adc_set_clk back into spear_write_raw, where it seems to have been located originally, and get rid of it afterwards (it doesn't do anything fancy, anyway). Sorry for bringing that up so late.

Btw: during the last weeks, I did
some review of about 75% of the stable adc drivers and piled up about 50 cleanup-patches so far, that I would send out soon. I also plan to do the same on the staging adc drivers afterwards. So, if you can be patient, I might do already a lot of cleanup, that you don't like to waste your time on ;-)

Thanks,

Hartmut

Quoted 6 lines

Quoted 1 line

Thanks, Stefan

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Quoted 5 lines · Hartmut Knaack

Quoted 4 lines · Jonathan Cameron

This simple driver is ready to move out of staging.

Signed-off-by Jonathan Cameron <[email protected]>

Acked-by Stefan Roese <[email protected]>

Stefan, there are some 'what is going on?' questions in here you might want to answer!

Quoted 9 lines

Quoted 9 lines

---
  drivers/iio/adc/Kconfig             |   8 +
  drivers/iio/adc/Makefile            |   1 +
  drivers/iio/adc/spear_adc.c         | 405 ++++++++++++++++++++++++++++++++++++
  drivers/staging/iio/adc/Kconfig     |   8 -
  drivers/staging/iio/adc/Makefile    |   1 -
  drivers/staging/iio/adc/spear_adc.c | 405 ------------------------------------
  6 files changed, 414 insertions(+), 414 deletions(-)

Quoted 6 lines

drivers/iio/adc/Kconfig config NAU7802 · line 164

Quoted 6 lines

drivers/iio/adc/Kconfig +0 -0

index 5553206..2e3e1b0 100644
@@ -164,6 +164,14 @@ config NAU7802
        To compile this driver as a module, choose M here: the

s>> module will be called nau7802.

Quoted 27 lines

Quoted 27 lines

drivers/iio/adc/Kconfig +8 -0

+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.
+
  config TI_ADC081C
      tristate "Texas Instruments ADC081C021/027"
      depends on I2C

drivers/iio/adc/Makefile +1 -0

index 89f1216..8378fb2 100644
@@ -18,6 +18,7 @@ obj-$(CONFIG_MAX1363) += max1363.o
  obj-$(CONFIG_MCP320X) += mcp320x.o
  obj-$(CONFIG_MCP3422) += mcp3422.o
  obj-$(CONFIG_NAU7802) += nau7802.o
+obj-$(CONFIG_SPEAR_ADC) += spear_adc.o
  obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
  obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
  obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o

drivers/iio/adc/spear_adc.c new file +0 -0

new file mode 100644
index 0000000..18a0a40

Quoted 8 lines

drivers/iio/adc/spear_adc.c line 4

Quoted 7 lines

drivers/iio/adc/spear_adc.c new file +4 -0

@@ -0,0 +1,405 @@
+/*
+ * ST SPEAr ADC driver
+ *
+ * Copyright 2012 Stefan Roese <[email protected]>

I found a datasheet at http://www.st.com/st-web-ui/static/active/en/resource/technical/document/reference_manual/DM00034813.pdf