[PATCH v7 0/2] iio: sx9310: Support ACPI properties

[PATCH v7 0/2] iio: sx9310: Support ACPI properties

[Gwendal Grignou]

Current sx9310 driver only support device tree properties.
Add support to read ACPI properties as well by converting calls
of_property_read_uXX() to device_property_read_uXX().

A bug was uncovered: if "semtech,combined-sensors" array was less than
4 entries, its content would be ignored, as of_property_read_u32_array
would return -EOVERFLOW.

Changes in v7:
Used incorrect device object in v6 to retrieve device tree properties.
Fully tested on machines with device tree and ACPI bindings.

Gwendal Grignou (2):
  iio: sx9310: Fix access to variable DT array
  iio: sx9310: Support ACPI properties

 drivers/iio/proximity/sx9310.c | 56 +++++++++++++++++++++-------------
 1 file changed, 34 insertions(+), 22 deletions(-)

-- 
2.31.0.291.g576ba9dcdaf-goog

[PATCH v7 1/2] iio: sx9310: Fix access to variable DT array

[Gwendal Grignou]

With the current code, we want to read 4 entries from DT array
"semtech,combined-sensors". If there are less, we silently fail as
of_property_read_u32_array() returns -EOVERFLOW.

First count the number of entries and if between 1 and 4, collect the
content of the array.

Fixes: 5b19ca2c78a0 ("iio: sx9310: Set various settings from DT")
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
---
 No changes in v7.

 Changes in v6:
 Fix error in of_property_count_elems_of_size() argumnent:
 Used ARRAY_SIZE(combined) [4] instead of sizeof(u32).

 Changes in v5:
 new, split fixes from changes needed for ACPI support.

 drivers/iio/proximity/sx9310.c | 40 ++++++++++++++++++++++++----------
 1 file changed, 28 insertions(+), 12 deletions(-)

diff --git a/drivers/iio/proximity/sx9310.c b/drivers/iio/proximity/sx9310.c
index 394c2afe0f233..289c76bb3b024 100644
--- a/drivers/iio/proximity/sx9310.c
+++ b/drivers/iio/proximity/sx9310.c
@@ -1213,17 +1213,17 @@ static int sx9310_init_compensation(struct iio_dev *indio_dev)
 }
 
 static const struct sx9310_reg_default *
-sx9310_get_default_reg(struct sx9310_data *data, int i,
+sx9310_get_default_reg(struct sx9310_data *data, int idx,
 		       struct sx9310_reg_default *reg_def)
 {
-	int ret;
 	const struct device_node *np = data->client->dev.of_node;
-	u32 combined[SX9310_NUM_CHANNELS] = { 4, 4, 4, 4 };
+	u32 combined[SX9310_NUM_CHANNELS];
+	u32 start = 0, raw = 0, pos = 0;
 	unsigned long comb_mask = 0;
+	int ret, i, count;
 	const char *res;
-	u32 start = 0, raw = 0, pos = 0;
 
-	memcpy(reg_def, &sx9310_default_regs[i], sizeof(*reg_def));
+	memcpy(reg_def, &sx9310_default_regs[idx], sizeof(*reg_def));
 	if (!np)
 		return reg_def;
 
@@ -1234,15 +1234,31 @@ sx9310_get_default_reg(struct sx9310_data *data, int i,
 			reg_def->def |= SX9310_REG_PROX_CTRL2_SHIELDEN_GROUND;
 		}
 
-		reg_def->def &= ~SX9310_REG_PROX_CTRL2_COMBMODE_MASK;
-		of_property_read_u32_array(np, "semtech,combined-sensors",
-					   combined, ARRAY_SIZE(combined));
-		for (i = 0; i < ARRAY_SIZE(combined); i++) {
-			if (combined[i] <= SX9310_NUM_CHANNELS)
-				comb_mask |= BIT(combined[i]);
+		count = of_property_count_elems_of_size(np, "semtech,combined-sensors",
+							sizeof(u32));
+		if (count > 0 && count <= ARRAY_SIZE(combined)) {
+			ret = of_property_read_u32_array(np, "semtech,combined-sensors",
+							 combined, count);
+			if (ret)
+				break;
+		} else {
+			/*
+			 * Either the property does not exist in the DT or the
+			 * number of entries is incorrect.
+			 */
+			break;
+		}
+		for (i = 0; i < count; i++) {
+			if (combined[i] >= SX9310_NUM_CHANNELS) {
+				/* Invalid sensor (invalid DT). */
+				break;
+			}
+			comb_mask |= BIT(combined[i]);
 		}
+		if (i < count)
+			break;
 
-		comb_mask &= 0xf;
+		reg_def->def &= ~SX9310_REG_PROX_CTRL2_COMBMODE_MASK;
 		if (comb_mask == (BIT(3) | BIT(2) | BIT(1) | BIT(0)))
 			reg_def->def |= SX9310_REG_PROX_CTRL2_COMBMODE_CS0_CS1_CS2_CS3;
 		else if (comb_mask == (BIT(1) | BIT(2)))
-- 
2.31.0.291.g576ba9dcdaf-goog

[PATCH v7 2/2] iio: sx9310: Support ACPI properties

[Gwendal Grignou]

Use device_property_read_uXX to support both device tree and ACPI
bindings when reading the properties we need to configure the SAR
sensor.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
---
 Changes in v7:
 Use proper device object to access properties.
 Verify it works both on machines with device-tree or ACPI bindings.

 Changes in v6:
 Use proper function to gather the number of elements in an array.

 Changes in v5:
 Split in 2 patches, one for fixing access to propery array, the other
 to support ACPI.

 drivers/iio/proximity/sx9310.c | 26 +++++++++++---------------
 1 file changed, 11 insertions(+), 15 deletions(-)

diff --git a/drivers/iio/proximity/sx9310.c b/drivers/iio/proximity/sx9310.c
index 289c76bb3b024..578d8841c5398 100644
--- a/drivers/iio/proximity/sx9310.c
+++ b/drivers/iio/proximity/sx9310.c
@@ -20,6 +20,7 @@
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/pm.h>
+#include <linux/property.h>
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 #include <linux/slab.h>
@@ -1213,10 +1214,9 @@ static int sx9310_init_compensation(struct iio_dev *indio_dev)
 }
 
 static const struct sx9310_reg_default *
-sx9310_get_default_reg(struct sx9310_data *data, int idx,
+sx9310_get_default_reg(struct device *dev, int idx,
 		       struct sx9310_reg_default *reg_def)
 {
-	const struct device_node *np = data->client->dev.of_node;
 	u32 combined[SX9310_NUM_CHANNELS];
 	u32 start = 0, raw = 0, pos = 0;
 	unsigned long comb_mask = 0;
@@ -1224,21 +1224,17 @@ sx9310_get_default_reg(struct sx9310_data *data, int idx,
 	const char *res;
 
 	memcpy(reg_def, &sx9310_default_regs[idx], sizeof(*reg_def));
-	if (!np)
-		return reg_def;
-
 	switch (reg_def->reg) {
 	case SX9310_REG_PROX_CTRL2:
-		if (of_property_read_bool(np, "semtech,cs0-ground")) {
+		if (device_property_read_bool(dev, "semtech,cs0-ground")) {
 			reg_def->def &= ~SX9310_REG_PROX_CTRL2_SHIELDEN_MASK;
 			reg_def->def |= SX9310_REG_PROX_CTRL2_SHIELDEN_GROUND;
 		}
 
-		count = of_property_count_elems_of_size(np, "semtech,combined-sensors",
-							sizeof(u32));
+		count = device_property_count_u32(dev, "semtech,combined-sensors");
 		if (count > 0 && count <= ARRAY_SIZE(combined)) {
-			ret = of_property_read_u32_array(np, "semtech,combined-sensors",
-							 combined, count);
+			ret = device_property_read_u32_array(dev, "semtech,combined-sensors",
+							     combined, count);
 			if (ret)
 				break;
 		} else {
@@ -1270,7 +1266,7 @@ sx9310_get_default_reg(struct sx9310_data *data, int idx,
 
 		break;
 	case SX9310_REG_PROX_CTRL4:
-		ret = of_property_read_string(np, "semtech,resolution", &res);
+		ret = device_property_read_string(dev, "semtech,resolution", &res);
 		if (ret)
 			break;
 
@@ -1294,7 +1290,7 @@ sx9310_get_default_reg(struct sx9310_data *data, int idx,
 
 		break;
 	case SX9310_REG_PROX_CTRL5:
-		ret = of_property_read_u32(np, "semtech,startup-sensor", &start);
+		ret = device_property_read_u32(dev, "semtech,startup-sensor", &start);
 		if (ret) {
 			start = FIELD_GET(SX9310_REG_PROX_CTRL5_STARTUPSENS_MASK,
 					  reg_def->def);
@@ -1304,7 +1300,7 @@ sx9310_get_default_reg(struct sx9310_data *data, int idx,
 		reg_def->def |= FIELD_PREP(SX9310_REG_PROX_CTRL5_STARTUPSENS_MASK,
 					   start);
 
-		ret = of_property_read_u32(np, "semtech,proxraw-strength", &raw);
+		ret = device_property_read_u32(dev, "semtech,proxraw-strength", &raw);
 		if (ret) {
 			raw = FIELD_GET(SX9310_REG_PROX_CTRL5_RAWFILT_MASK,
 					reg_def->def);
@@ -1317,7 +1313,7 @@ sx9310_get_default_reg(struct sx9310_data *data, int idx,
 					   raw);
 		break;
 	case SX9310_REG_PROX_CTRL7:
-		ret = of_property_read_u32(np, "semtech,avg-pos-strength", &pos);
+		ret = device_property_read_u32(dev, "semtech,avg-pos-strength", &pos);
 		if (ret)
 			break;
 
@@ -1353,7 +1349,7 @@ static int sx9310_init_device(struct iio_dev *indio_dev)
 
 	/* Program some sane defaults. */
 	for (i = 0; i < ARRAY_SIZE(sx9310_default_regs); i++) {
-		initval = sx9310_get_default_reg(data, i, &tmp);
+		initval = sx9310_get_default_reg(&data->client->dev, i, &tmp);
 		ret = regmap_write(data->regmap, initval->reg, initval->def);
 		if (ret)
 			return ret;
-- 
2.31.0.291.g576ba9dcdaf-goog

Re: [PATCH v7 1/2] iio: sx9310: Fix access to variable DT array

[Jonathan Cameron]

On Fri, 26 Mar 2021 11:46:02 -0700
Gwendal Grignou <gwendal@chromium.org> wrote:

> With the current code, we want to read 4 entries from DT array
> "semtech,combined-sensors". If there are less, we silently fail as
> of_property_read_u32_array() returns -EOVERFLOW.
> 
> First count the number of entries and if between 1 and 4, collect the
> content of the array.
> 
> Fixes: 5b19ca2c78a0 ("iio: sx9310: Set various settings from DT")
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

Applying this one to the fixes-togreg branch of iio.git.

As the second patch isn't a fix it might take a while to get applied.
Gwendal, feel free to poke me if I seem to have lost it after the first
patch reaches my togreg branch.

Thanks,

Jonathan

> ---
>  No changes in v7.
> 
>  Changes in v6:
>  Fix error in of_property_count_elems_of_size() argumnent:
>  Used ARRAY_SIZE(combined) [4] instead of sizeof(u32).
> 
>  Changes in v5:
>  new, split fixes from changes needed for ACPI support.
> 
>  drivers/iio/proximity/sx9310.c | 40 ++++++++++++++++++++++++----------
>  1 file changed, 28 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/iio/proximity/sx9310.c b/drivers/iio/proximity/sx9310.c
> index 394c2afe0f233..289c76bb3b024 100644
> --- a/drivers/iio/proximity/sx9310.c
> +++ b/drivers/iio/proximity/sx9310.c
> @@ -1213,17 +1213,17 @@ static int sx9310_init_compensation(struct iio_dev *indio_dev)
>  }
>  
>  static const struct sx9310_reg_default *
> -sx9310_get_default_reg(struct sx9310_data *data, int i,
> +sx9310_get_default_reg(struct sx9310_data *data, int idx,
>  		       struct sx9310_reg_default *reg_def)
>  {
> -	int ret;
>  	const struct device_node *np = data->client->dev.of_node;
> -	u32 combined[SX9310_NUM_CHANNELS] = { 4, 4, 4, 4 };
> +	u32 combined[SX9310_NUM_CHANNELS];
> +	u32 start = 0, raw = 0, pos = 0;
>  	unsigned long comb_mask = 0;
> +	int ret, i, count;
>  	const char *res;
> -	u32 start = 0, raw = 0, pos = 0;
>  
> -	memcpy(reg_def, &sx9310_default_regs[i], sizeof(*reg_def));
> +	memcpy(reg_def, &sx9310_default_regs[idx], sizeof(*reg_def));
>  	if (!np)
>  		return reg_def;
>  
> @@ -1234,15 +1234,31 @@ sx9310_get_default_reg(struct sx9310_data *data, int i,
>  			reg_def->def |= SX9310_REG_PROX_CTRL2_SHIELDEN_GROUND;
>  		}
>  
> -		reg_def->def &= ~SX9310_REG_PROX_CTRL2_COMBMODE_MASK;
> -		of_property_read_u32_array(np, "semtech,combined-sensors",
> -					   combined, ARRAY_SIZE(combined));
> -		for (i = 0; i < ARRAY_SIZE(combined); i++) {
> -			if (combined[i] <= SX9310_NUM_CHANNELS)
> -				comb_mask |= BIT(combined[i]);
> +		count = of_property_count_elems_of_size(np, "semtech,combined-sensors",
> +							sizeof(u32));
> +		if (count > 0 && count <= ARRAY_SIZE(combined)) {
> +			ret = of_property_read_u32_array(np, "semtech,combined-sensors",
> +							 combined, count);
> +			if (ret)
> +				break;
> +		} else {
> +			/*
> +			 * Either the property does not exist in the DT or the
> +			 * number of entries is incorrect.
> +			 */
> +			break;
> +		}
> +		for (i = 0; i < count; i++) {
> +			if (combined[i] >= SX9310_NUM_CHANNELS) {
> +				/* Invalid sensor (invalid DT). */
> +				break;
> +			}
> +			comb_mask |= BIT(combined[i]);
>  		}
> +		if (i < count)
> +			break;
>  
> -		comb_mask &= 0xf;
> +		reg_def->def &= ~SX9310_REG_PROX_CTRL2_COMBMODE_MASK;
>  		if (comb_mask == (BIT(3) | BIT(2) | BIT(1) | BIT(0)))
>  			reg_def->def |= SX9310_REG_PROX_CTRL2_COMBMODE_CS0_CS1_CS2_CS3;
>  		else if (comb_mask == (BIT(1) | BIT(2)))