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

PATCH Superseded Jonathan Cameron 3 participants 11 messages Mar 11, 2014 – Mar 15, 2014

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Jonathan Cameron

author maintainer

2014-03-11 20:36 UTC #0 lore raw

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

This driver has been reasonably clean since it was first merged within the staging tree. If it had been submitted after the IIO core was outside of staging we might have taken it as is. I did a final review and the first 4 patches of this series rework various minor aspects of the driver.

Whilst it is a slow driver, the device tree matches at the lowest level seemed a little unwise so the largest rework is concerned with centralising that logic using a classic ops structure of function pointers. The other large change was to move to using the info_mask_shared_by_all approach to handle sampling frequency. This is something I am slowly propogating across the whole tree, but might as well be done whilst we are looking at this driver.

I don't have hardware and whilst I think these are all changes that are possible to easily verify by eye, a tested by would be most welcome!

Note this is the first driver I'm suggesting moving out of staging following Greg's entirely reasonable question of 'What's wrong with the stuff that is left?' Any help with this sort of final cleanup and move would be most welcome.

Jonathan

Jonathan Cameron (5):
staging:iio:adc:spear adc - prefix defines to avoid namespace clashes. staging:iio:adc:spear adc rework so that device tree queries are all
in probe
staging:iio:adc:spear_adc drop initialization of unused scan_type staging:iio:adc:spear_adc use info_mask_shared_by_all for samp freq iio:adc:spear_adc move out of staging

 drivers/iio/adc/Kconfig             |   8 +
 drivers/iio/adc/Makefile            |   1 +
 drivers/iio/adc/spear_adc.c         | 429 +++++++++++++++++++++++++++++++++++
 drivers/staging/iio/adc/Kconfig     |   8 -
 drivers/staging/iio/adc/Makefile    |   1 -
 drivers/staging/iio/adc/spear_adc.c | 432 ------------------------------------
 6 files changed, 438 insertions(+), 441 deletions(-)
 create mode 100644 drivers/iio/adc/spear_adc.c
 delete mode 100644 drivers/staging/iio/adc/spear_adc.c

Signature · 1 line

1.9.0

Jonathan Cameron

author maintainer

2014-03-11 20:36 UTC #1 lore raw

PATCH 1/5 staging:iio:adc:spear adc - prefix defines to avoid namespace clashes.

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

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

drivers/staging/iio/adc/spear_adc.c +36 ~~-37~~

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;
 	}
 
-	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);
 	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),
 	},

Signature · 1 line

1.9.0

Jonathan Cameron

author maintainer

2014-03-11 20:36 UTC #2 lore raw

PATCH 2/5 staging:iio:adc:spear adc rework so that device tree queries are all in probe

In reply to Jonathan Cameron

Previously the driver would query what type it was in very low level functions. This is unintuitive and probably rather inefficient.

Also combine the two structure pointers using an anonymous union given only one should be set for a given device.

Clearly the of_device_is_compatible related logic in probe could assign only one of the two pointers, but I feel it is clearer as done here.

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

---
 drivers/staging/iio/adc/spear_adc.c | 89 ++++++++++++++++++++++++-------------
 1 file changed, 57 insertions(+), 32 deletions(-)

drivers/staging/iio/adc/spear_adc.c +57 ~~-32~~

index 9234e05..886d9db 100644
@@ -70,10 +70,20 @@ struct adc_regs_spear6xx {
 	struct chan_data average;
 };
 
+struct spear_adc_info;
+
+struct spear_adc_ops {
+	u32 (*get_average)(struct spear_adc_info *info);
+	void (*set_scanrate)(struct spear_adc_info *info, u32 rate);
+};
+
 struct spear_adc_info {
 	struct device_node *np;
-	struct adc_regs_spear3xx __iomem *adc_base_spear3xx;
-	struct adc_regs_spear6xx __iomem *adc_base_spear6xx;
+	union {
+		struct adc_regs_spear3xx __iomem *adc_base_spear3xx;
+		struct adc_regs_spear6xx __iomem *adc_base_spear6xx;
+	};
+	const struct spear_adc_ops *ops;
 	struct clk *clk;
 	struct completion completion;
 	u32 current_clk;

@@ -83,11 +93,6 @@ struct spear_adc_info {
 	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);

@@ -113,29 +118,41 @@ static void spear_adc_set_ctrl(struct spear_adc_info *info, int n,
 	__raw_writel(val, &info->adc_base_spear6xx->ch_ctrl[n]);
 }
 
-static u32 spear_adc_get_average(struct spear_adc_info *info)
+static u32 spear600_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;
-	}
+	return __raw_readl(&info->adc_base_spear6xx->average.msb) &
+		SPEAR_ADC_DATA_MASK;
 }
 
-static void spear_adc_set_scanrate(struct spear_adc_info *info, u32 rate)
+static u32 spear300_adc_get_average(struct spear_adc_info *info)
 {
-	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);
-	}
+	return __raw_readl(&info->adc_base_spear3xx->average) &
+		SPEAR_ADC_DATA_MASK;
+}
+
+static void spear600_adc_set_scanrate(struct spear_adc_info *info, u32 rate)
+{
+	__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);
+}
+
+static void spear300_adc_set_scanrate(struct spear_adc_info *info, u32 rate)
+{
+	__raw_writel(rate, &info->adc_base_spear3xx->scan_rate);
 }
 
+static const struct spear_adc_ops spear600_adc_ops = {
+	.get_average = &spear600_adc_get_average,
+	.set_scanrate = &spear600_adc_set_scanrate,
+};
+
+static const struct spear_adc_ops spear300_adc_ops = {
+	.get_average = &spear300_adc_get_average,
+	.set_scanrate = &spear300_adc_set_scanrate,
+};
+
 static int spear_read_raw(struct iio_dev *indio_dev,
 			  struct iio_chan_spec const *chan,
 			  int *val,

@@ -201,7 +218,7 @@ 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);
+	info->value = info->ops->get_average(info);
 	complete(&info->completion);
 
 	return IRQ_HANDLED;

@@ -216,7 +233,7 @@ static int spear_adc_configure(struct spear_adc_info *info)
 	__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);
+	info->ops->set_scanrate(info, 0);
 
 	spear_adc_set_clk(info, info->sampling_freq);

@@ -310,13 +327,21 @@ static int spear_adc_probe(struct platform_device *pdev)
 	 * (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;
+	if (of_device_is_compatible(info->np, "st,spear600-adc")) {
+		info->adc_base_spear6xx = of_iomap(np, 0);
+		if (!info->adc_base_spear6xx) {
+			dev_err(dev, "failed mapping memory\n");
+			return -ENOMEM;
+		}
+		info->ops = &spear600_adc_ops;
+	} else {
+		info->adc_base_spear3xx = of_iomap(np, 0);
+		if (!info->adc_base_spear3xx) {
+			dev_err(dev, "failed mapping memory\n");
+			return -ENOMEM;
+		}
+		info->ops = &spear300_adc_ops;
 	}
-	info->adc_base_spear3xx =
-		(struct adc_regs_spear3xx __iomem *)info->adc_base_spear6xx;
 
 	info->clk = clk_get(dev, NULL);
 	if (IS_ERR(info->clk)) {

Signature · 1 line

1.9.0

Jonathan Cameron

author maintainer

2014-03-11 20:36 UTC #3 lore raw

PATCH 3/5 staging:iio:adc:spear_adc drop initialization of unused scan_type

In reply to Jonathan Cameron

As the driver does not support the buffered interfaces of IIO this is not used.

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

---
 drivers/staging/iio/adc/spear_adc.c | 4 ----
 1 file changed, 4 deletions(-)

drivers/staging/iio/adc/spear_adc.c +0 -4

index 886d9db..fbe69a7 100644
@@ -196,10 +196,6 @@ static int spear_read_raw(struct iio_dev *indio_dev,
 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
 	.channel = idx,					\
-	.scan_type = {					\
-		.sign = 'u',				\
-		.storagebits = 16,			\
-	},						\
 }
 
 static const struct iio_chan_spec spear_adc_iio_channels[] = {

Signature · 1 line

1.9.0

Jonathan Cameron

author maintainer

2014-03-11 20:36 UTC #4 lore raw

PATCH 4/5 staging:iio:adc:spear_adc use info_mask_shared_by_all for samp freq

In reply to 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.

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

---
 drivers/staging/iio/adc/spear_adc.c | 95 ++++++++++++++-----------------------
 1 file changed, 36 insertions(+), 59 deletions(-)

drivers/staging/iio/adc/spear_adc.c +36 ~~-59~~

index fbe69a7..d8232f1 100644
@@ -185,16 +185,51 @@ 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 clk_high, clk_low, count;
+	u32 apb_clk = clk_get_rate(info->clk);
+	int ret = 0;
+
+	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;
+	clk_low = count / 2;
+	clk_high = count - clk_low;
+	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,					\
 }

@@ -236,67 +271,9 @@ 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,
 };

Signature · 1 line

1.9.0

Hartmut Knaack

2014-03-12 20:31 UTC #5 lore raw

Re: [PATCH 4/5] staging:iio:adc:spear_adc use info_mask_shared_by_all for samp freq

Quoted 42 lines · Jonathan Cameron

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

---
 drivers/staging/iio/adc/spear_adc.c | 95 ++++++++++++++-----------------------
 1 file changed, 36 insertions(+), 59 deletions(-)

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

index fbe69a7..d8232f1 100644
@@ -185,16 +185,51 @@ 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 clk_high, clk_low, count;
+	u32 apb_clk = clk_get_rate(info->clk);
+	int ret = 0;
+
+	mutex_lock(&indio_dev->mlock);
+
+	if ((val < SPEAR_ADC_CLK_MIN) ||
+		(val > SPEAR_ADC_CLK_MAX) ||
+		(val2 != 0)) {

drivers/staging/iio/adc/spear_adc.c static int spear_read_raw(struct iio_dev *indio_dev, · line 221

Quoted 10 lines

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

+		ret = -EINVAL;
+		goto out;
+	}
+
+	count = (apb_clk + val - 1) / val;
+	clk_low = count / 2;
+	clk_high = count - clk_low;
+	info->current_clk = apb_clk / count;
+	spear_adc_set_clk(info, val);
+

What is actually the purpose of clk_low and clk_high? I don't see them used after doing that calculation. And is it really 100% safe to avoid checking mask?

Quoted 83 lines

drivers/staging/iio/adc/spear_adc.c +7 ~~-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,					\
 }

@@ -236,67 +271,9 @@ 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,
 };

Jonathan Cameron

author maintainer

2014-03-15 14:48 UTC #6 lore raw

Re: [PATCH 4/5] staging:iio:adc:spear_adc use info_mask_shared_by_all for samp freq

Quoted 46 lines · Hartmut Knaack

Quoted 45 lines · Jonathan Cameron

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

---
  drivers/staging/iio/adc/spear_adc.c | 95 ++++++++++++++-----------------------
  1 file changed, 36 insertions(+), 59 deletions(-)

drivers/staging/iio/adc/spear_adc.c +22 -0

index fbe69a7..d8232f1 100644
@@ -185,16 +185,51 @@ 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 clk_high, clk_low, count;
+	u32 apb_clk = clk_get_rate(info->clk);
+	int ret = 0;
+
+	mutex_lock(&indio_dev->mlock);
+
+	if ((val < SPEAR_ADC_CLK_MIN) ||
+		(val > SPEAR_ADC_CLK_MAX) ||
+		(val2 != 0)) {
+		ret = -EINVAL;
+		goto out;
+	}

Quoted 8 lines

drivers/staging/iio/adc/spear_adc.c static int spear_read_raw(struct iio_dev *indio_dev, · line 221
Quoted 7 lines
drivers/staging/iio/adc/spear_adc.c +7 -0
+
+	count = (apb_clk + val - 1) / val;
+	clk_low = count / 2;
+	clk_high = count - clk_low;
+	info->current_clk = apb_clk / count;
+	spear_adc_set_clk(info, val);
+
What is actually the purpose of clk_low and clk_high? I don't see them used after doing that calculation.

Good spot. Looks like this is the result of an earlier reworking. These get recomputed in the set_clk function.

Quoted 1 line

And is it really 100% safe to avoid checking mask?

Fair point. No it's not. Oops. Will fix and repost in a sec.

Quoted 89 lines

Quoted 73 lines

drivers/staging/iio/adc/spear_adc.c +6 ~~-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,					\
  }

@@ -236,67 +271,9 @@ 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 279

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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Jonathan Cameron

author maintainer

2014-03-11 20:36 UTC #7 lore raw

PATCH 5/5 iio:adc:spear_adc move out of staging

In reply to Jonathan Cameron

This simple driver is ready to move out of staging.

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

---
 drivers/iio/adc/Kconfig             |   8 +
 drivers/iio/adc/Makefile            |   1 +
 drivers/iio/adc/spear_adc.c         | 429 ++++++++++++++++++++++++++++++++++++
 drivers/staging/iio/adc/Kconfig     |   8 -
 drivers/staging/iio/adc/Makefile    |   1 -
 drivers/staging/iio/adc/spear_adc.c | 429 ------------------------------------
 6 files changed, 438 insertions(+), 438 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 +429 -0

429 lines not on this page · raw message

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 ~~-429~~

429 lines not on this page · raw message

Signature · 1 line

1.9.0

Hartmut Knaack

2014-03-12 20:46 UTC #8 lore raw

Re: [PATCH 5/5] iio:adc:spear_adc move out of staging

Quoted 17 lines · Jonathan Cameron

This simple driver is ready to move out of staging.

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

---
 drivers/iio/adc/Kconfig             |   8 +
 drivers/iio/adc/Makefile            |   1 +
 drivers/iio/adc/spear_adc.c         | 429 ++++++++++++++++++++++++++++++++++++
 drivers/staging/iio/adc/Kconfig     |   8 -
 drivers/staging/iio/adc/Makefile    |   1 -
 drivers/staging/iio/adc/spear_adc.c | 429 ------------------------------------
 6 files changed, 438 insertions(+), 438 deletions(-)

drivers/iio/adc/Kconfig +0 -0

index 5553206..2e3e1b0 100644

drivers/iio/adc/Kconfig config NAU7802 · line 169

Quoted 6 lines

drivers/iio/adc/Kconfig +3 -0

@@ -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

Are you sure to keep COMPILE_TEST in?

Quoted 9 lines

drivers/iio/adc/Kconfig +5 -0

+	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

Jonathan Cameron

author maintainer

2014-03-13 15:45 UTC #9 lore raw

Re: [PATCH 5/5] iio:adc:spear_adc move out of staging

Quoted 23 lines · Hartmut Knaack

Quoted 7 lines · Jonathan Cameron
This simple driver is ready to move out of staging.
Signed-off-by Jonathan Cameron <[email protected]>
---
 drivers/iio/adc/Kconfig             |   8 +
 drivers/iio/adc/Makefile            |   1 +
 drivers/iio/adc/spear_adc.c         | 429
++++++++++++++++++++++++++++++++++++
Quoted 3 lines
 drivers/staging/iio/adc/Kconfig     |   8 -
 drivers/staging/iio/adc/Makefile    |   1 -
 drivers/staging/iio/adc/spear_adc.c | 429
------------------------------------
Quoted 10 lines
 6 files changed, 438 insertions(+), 438 deletions(-)
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
 	  module will be called nau7802.
 

Quoted 4 lines

drivers/iio/adc/Kconfig config NAU7802 · line 169
Quoted 3 lines
drivers/iio/adc/Kconfig +3 -0
+config SPEAR_ADC
+	tristate "ST SPEAr ADC"
+	depends on PLAT_SPEAR || COMPILE_TEST
Are you sure to keep COMPILE_TEST in?

Yes. Allows those without a spear specific config to build test. Prevents a lot of bugs sneaking in for more obscure platforms.

We do this for any drivers that don't require any other support from the platform.

Quoted 9 lines

drivers/iio/adc/Kconfig +5 -0

+	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

Signature · 1 line

Sent from my Android phone with K-9 Mail. Please excuse my brevity.

Stefan Roese

2014-03-12 06:50 UTC #10 lore raw

In reply to Jonathan Cameron

Quoted 12 lines · Jonathan Cameron

This driver has been reasonably clean since it was first merged within the staging tree. If it had been submitted after the IIO core was outside of staging we might have taken it as is. I did a final review and the first 4 patches of this series rework various minor aspects of the driver.
Whilst it is a slow driver, the device tree matches at the lowest level seemed a little unwise so the largest rework is concerned with centralising that logic using a classic ops structure of function pointers. The other large change was to move to using the info_mask_shared_by_all approach to handle sampling frequency. This is something I am slowly propogating across the whole tree, but might as well be done whilst we are looking at this driver.

Quoted 7 lines

I don't have hardware and whilst I think these are all changes that are possible to easily verify by eye, a tested by would be most welcome!
Note this is the first driver I'm suggesting moving out of staging following Greg's entirely reasonable question of 'What's wrong with the stuff that is left?' Any help with this sort of final cleanup and move would be most welcome.

Jonathan, thanks for working on this. Really appreciated. I don't have a spear600 board at hand right now. But all your changes seem reasonable. So:

Ackey-by Stefan Roese <[email protected]>

Thanks,
Stefan