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* [PATCH v5 0/2] hwmon: (adt7475) Added attenuator bypass support
@ 2020-01-23 22:05 Logan Shaw
  2020-01-23 22:05 ` [PATCH v5 1/2] " Logan Shaw
  2020-01-23 22:05 ` [PATCH v5 2/2] dt-bindings: hwmon: (adt7475) Added missing adt7475 doccumentation Logan Shaw
  0 siblings, 2 replies; 5+ messages in thread
From: Logan Shaw @ 2020-01-23 22:05 UTC (permalink / raw)
  To: linux, jdelvare, robh+dt
  Cc: linux-hwmon, linux-kernel, devicetree, Joshua.Scott,
	Chris.Packham, logan.shaw

The ADT7473 and ADT7475 support bypassing voltage input attenuators on
voltage input 1 and the ADT7476 and ADT7490 additionally support
bypassing voltage input attenuators on voltage inputs 0, 3, and 4. This
can be useful to improve measurement resolution when measuring voltages
0 V - 2.25 V.

This patch adds 4 optional devicetree properties to the adt7475
driver, each setting the attenuator bypass (or clearing) on a
specific voltage input.

* v5
- modified adt7475.yaml to remove dt_binding_check errors
- made various alignment fixes to adt7475.c to improve style.
- renamed function modify_config_from_dts_prop to modify_config
- changed return type of function modify_config to void
- function modify_config error return code modified no longer override
  the dependent functions i2c_smbus_write_byte_data error.
- renamed function load_all_bypass_attenuators to load_attenuators
- in function load_attenuators the two local variables config2_copy
  and config4_copy have been combined into one: conf_copy.

* v4
- fixed a small error in file adt7475.yaml (duplicate property names).

* v3
- removed the functionality to set the global attenuator bypass.
- added functionality to allow bypassing voltage input 1 on the
	ADT7473 and ADT7475.
- added DTS definition file adt7475.yaml and 4 new properties.
- added the previousely missing newline character to the end of
  	file adt7475.c. 

* v2
- removed sysfs changes from patch
- removed adt7475_write macro from patch and replaced it by using
	the i2c_smbus_write_byte_data function directly in code.
- removed config4_attenuate_index function from patch and replaced it
	by modifying the function  load_individual_bypass_attenuators
	to use hard coded bit values.
- modified function load_individual_bypass_attenuators to use 4 if
	statements, one for each voltage input, replacing the for loop.
- modified function adt7475_probe to check the device is a ADT7476 or
	ADT7490 (other devices do not support bypassing all or
	individual attenuators), and only then set the relevant bits.
- added new file adt7475.txt to document the new devicetree properties.
- removed c++ style comments. 

Logan Shaw (2):
  hwmon: (adt7475) Added attenuator bypass support
  dt-bindings: hwmon: (adt7475) Added missing adt7475 doccumentation

 .../devicetree/bindings/hwmon/adt7475.yaml    | 95 +++++++++++++++++++
 drivers/hwmon/adt7475.c                       | 68 +++++++++++++
 2 files changed, 163 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwmon/adt7475.yaml

-- 
2.25.0


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH v5 1/2] hwmon: (adt7475) Added attenuator bypass support
  2020-01-23 22:05 [PATCH v5 0/2] hwmon: (adt7475) Added attenuator bypass support Logan Shaw
@ 2020-01-23 22:05 ` " Logan Shaw
  2020-01-24  4:55   ` Guenter Roeck
  2020-01-23 22:05 ` [PATCH v5 2/2] dt-bindings: hwmon: (adt7475) Added missing adt7475 doccumentation Logan Shaw
  1 sibling, 1 reply; 5+ messages in thread
From: Logan Shaw @ 2020-01-23 22:05 UTC (permalink / raw)
  To: linux, jdelvare, robh+dt
  Cc: linux-hwmon, linux-kernel, devicetree, Joshua.Scott,
	Chris.Packham, logan.shaw

Added support for reading DTS properties to set attenuators on
device probe for the ADT7473, ADT7475, ADT7476, and ADT7490.

Signed-off-by: Logan Shaw <logan.shaw@alliedtelesis.co.nz>
---
---
 drivers/hwmon/adt7475.c | 68 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)

diff --git a/drivers/hwmon/adt7475.c b/drivers/hwmon/adt7475.c
index 6c64d50c9aae..8afc5a89ec92 100644
--- a/drivers/hwmon/adt7475.c
+++ b/drivers/hwmon/adt7475.c
@@ -19,6 +19,7 @@
 #include <linux/hwmon-vid.h>
 #include <linux/err.h>
 #include <linux/jiffies.h>
+#include <linux/of.h>
 #include <linux/util_macros.h>
 
 /* Indexes for the sysfs hooks */
@@ -1457,6 +1458,70 @@ static int adt7475_update_limits(struct i2c_client *client)
 	return 0;
 }
 
+/**
+ * Sets or clears the given bit in the config depending on the value of the
+ * given dts property. Non-zero value sets, zero value clears. No change if
+ * the property is absent.
+ */
+static void modify_config(const struct i2c_client *client, char *property,
+				u8 *config, u8 bit_index)
+{
+	u32 prop_value = 0;
+	int ret = of_property_read_u32(client->dev.of_node, property,
+					&prop_value);
+
+	if (!ret) {
+		if (prop_value)
+			*config |= (1 << bit_index);
+		else
+			*config &= ~(1 << bit_index);
+	}
+}
+
+/**
+ * Configures the attenuator bypasses for voltage inputs, depening on
+ * properties in the dts.
+.*
+ * The adt7473 and adt7475 only support bypassing in1.
+ *
+ * Returns a negative error code if there was an error writing to the register.
+ */
+static int load_attenuators(const struct i2c_client *client, int chip,
+				u8 *config2, u8 *config4)
+{
+	u8 conf_copy;
+	int ret = 0;
+
+	if (chip == adt7476 || chip == adt7490) {
+		conf_copy = *config4;
+
+		modify_config(client, "bypass-attenuator-in0", &conf_copy, 4);
+		modify_config(client, "bypass-attenuator-in1", &conf_copy, 5);
+		modify_config(client, "bypass-attenuator-in3", &conf_copy, 6);
+		modify_config(client, "bypass-attenuator-in4", &conf_copy, 7);
+
+		ret = i2c_smbus_write_byte_data(client, REG_CONFIG4,
+			conf_copy);
+		if (ret < 0)
+			return ret;
+
+		*config4 = conf_copy;
+	} else if (chip == adt7473 || chip == adt7475) {
+		conf_copy = *config2;
+
+		modify_config(client, "bypass-attenuator-in1", &conf_copy, 5);
+
+		ret = i2c_smbus_write_byte_data(client, REG_CONFIG2,
+			conf_copy);
+		if (ret < 0)
+			return ret;
+
+		*config2 = conf_copy;
+	}
+
+	return 0;
+}
+
 static int adt7475_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id)
 {
@@ -1546,6 +1611,9 @@ static int adt7475_probe(struct i2c_client *client,
 
 	/* Voltage attenuators can be bypassed, globally or individually */
 	config2 = adt7475_read(REG_CONFIG2);
+	if (load_attenuators(client, chip, &config2, &(data->config4)) < 0)
+		dev_warn(&client->dev, "Error setting bypass attenuators\n");
+
 	if (config2 & CONFIG2_ATTN) {
 		data->bypass_attn = (0x3 << 3) | 0x3;
 	} else {
-- 
2.25.0


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH v5 2/2] dt-bindings: hwmon: (adt7475) Added missing adt7475 doccumentation
  2020-01-23 22:05 [PATCH v5 0/2] hwmon: (adt7475) Added attenuator bypass support Logan Shaw
  2020-01-23 22:05 ` [PATCH v5 1/2] " Logan Shaw
@ 2020-01-23 22:05 ` Logan Shaw
  2020-01-25 23:09   ` Guenter Roeck
  1 sibling, 1 reply; 5+ messages in thread
From: Logan Shaw @ 2020-01-23 22:05 UTC (permalink / raw)
  To: linux, jdelvare, robh+dt
  Cc: linux-hwmon, linux-kernel, devicetree, Joshua.Scott,
	Chris.Packham, logan.shaw

Added a new file documenting the adt7475 devicetree and added the four
new properties to it.

Signed-off-by: Logan Shaw <logan.shaw@alliedtelesis.co.nz>
---
---
 .../devicetree/bindings/hwmon/adt7475.yaml    | 95 +++++++++++++++++++
 1 file changed, 95 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwmon/adt7475.yaml

diff --git a/Documentation/devicetree/bindings/hwmon/adt7475.yaml b/Documentation/devicetree/bindings/hwmon/adt7475.yaml
new file mode 100644
index 000000000000..450da5e66e07
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/adt7475.yaml
@@ -0,0 +1,95 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/adt7475.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ADT7475 hwmon sensor
+
+maintainers:
+  - Jean Delvare <jdelvare@suse.com>
+
+description: |
+  The ADT7473, ADT7475, ADT7476, and ADT7490 are thermal monitors and multiple
+  PWN fan controllers.
+
+  They support monitoring and controlling up to four fans (the ADT7490 can only
+  control up to three). They support reading a single on chip temperature
+  sensor and two off chip temperature sensors (the ADT7490 additionally
+  supports measuring up to three current external temperature sensors with
+  series resistance cancellation (SRC)).
+
+  Datasheets:
+  https://www.onsemi.com/pub/Collateral/ADT7473-D.PDF
+  https://www.onsemi.com/pub/Collateral/ADT7475-D.PDF
+  https://www.onsemi.com/pub/Collateral/ADT7476-D.PDF
+  https://www.onsemi.com/pub/Collateral/ADT7490-D.PDF
+
+  Description taken from omsemiconductors specification sheets, with minor
+  rephrasing.
+
+properties:
+  compatible:
+    enum:
+      - adi,adt7473
+      - adi,adt7475
+      - adi,adt7476
+      - adi,adt7490
+
+  reg:
+    maxItems: 1
+
+  bypass-attenuator-in0:
+    description: |
+      Configures bypassing the individual voltage input
+      attenuator, on in0. This is supported on the ADT7476 and ADT7490.
+      If set to a non-zero integer the attenuator is bypassed, if set to
+      zero the attenuator is not bypassed. If the property is absent then
+      the config register is not modified.
+    maxItems: 1
+
+  bypass-attenuator-in1:
+    description: |
+      Configures bypassing the individual voltage input
+      attenuator, on in1. This is supported on the ADT7473, ADT7475,
+      ADT7476 and ADT7490. If set to a non-zero integer the attenuator
+      is bypassed, if set to zero the attenuator is not bypassed. If the
+      property is absent then the config register is not modified.
+    maxItems: 1
+
+  bypass-attenuator-in3:
+    description: |
+      Configures bypassing the individual voltage input
+      attenuator, on in3. This is supported on the ADT7476 and ADT7490.
+      If set to a non-zero integer the attenuator is bypassed, if set to
+      zero the attenuator is not bypassed. If the property is absent then
+      the config register is not modified.
+    maxItems: 1
+
+  bypass-attenuator-in4:
+    description: |
+      Configures bypassing the individual voltage input
+      attenuator, on in4. This is supported on the ADT7476 and ADT7490.
+      If set to a non-zero integer the attenuator is bypassed, if set to
+      zero the attenuator is not bypassed. If the property is absent then
+      the config register is not modified.
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+examples:
+  - |
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      hwmon@2e {
+        compatible = "adi,adt7476";
+        reg = <0x2e>;
+        bypass-attenuator-in0 = <1>;
+        bypass-attenuator-in1 = <0>;
+      };
+    };
+...
-- 
2.25.0


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH v5 1/2] hwmon: (adt7475) Added attenuator bypass support
  2020-01-23 22:05 ` [PATCH v5 1/2] " Logan Shaw
@ 2020-01-24  4:55   ` Guenter Roeck
  0 siblings, 0 replies; 5+ messages in thread
From: Guenter Roeck @ 2020-01-24  4:55 UTC (permalink / raw)
  To: Logan Shaw, jdelvare, robh+dt
  Cc: linux-hwmon, linux-kernel, devicetree, Joshua.Scott, Chris.Packham

On 1/23/20 2:05 PM, Logan Shaw wrote:
> Added support for reading DTS properties to set attenuators on
> device probe for the ADT7473, ADT7475, ADT7476, and ADT7490.
> 
> Signed-off-by: Logan Shaw <logan.shaw@alliedtelesis.co.nz>
> ---
> ---
>   drivers/hwmon/adt7475.c | 68 +++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 68 insertions(+)
> 
> diff --git a/drivers/hwmon/adt7475.c b/drivers/hwmon/adt7475.c
> index 6c64d50c9aae..8afc5a89ec92 100644
> --- a/drivers/hwmon/adt7475.c
> +++ b/drivers/hwmon/adt7475.c
> @@ -19,6 +19,7 @@
>   #include <linux/hwmon-vid.h>
>   #include <linux/err.h>
>   #include <linux/jiffies.h>
> +#include <linux/of.h>
>   #include <linux/util_macros.h>
>   
>   /* Indexes for the sysfs hooks */
> @@ -1457,6 +1458,70 @@ static int adt7475_update_limits(struct i2c_client *client)
>   	return 0;
>   }
>   
> +/**

I am still at loss why you think it would make sense to mark those
comments for the kernel documentation. This doesn't have value outside
this driver.

> + * Sets or clears the given bit in the config depending on the value of the
> + * given dts property. Non-zero value sets, zero value clears. No change if
> + * the property is absent.
> + */
> +static void modify_config(const struct i2c_client *client, char *property,
> +				u8 *config, u8 bit_index)
> +{
> +	u32 prop_value = 0;
> +	int ret = of_property_read_u32(client->dev.of_node, property,
> +					&prop_value);
> +
> +	if (!ret) {
> +		if (prop_value)
> +			*config |= (1 << bit_index);
> +		else
> +			*config &= ~(1 << bit_index);
> +	}
> +}
> +
> +/**
> + * Configures the attenuator bypasses for voltage inputs, depening on
> + * properties in the dts.
> +.*
> + * The adt7473 and adt7475 only support bypassing in1.
> + *
> + * Returns a negative error code if there was an error writing to the register.
> + */
> +static int load_attenuators(const struct i2c_client *client, int chip,
> +				u8 *config2, u8 *config4)
> +{
> +	u8 conf_copy;
> +	int ret = 0;

Unnecessary assignment.

> +
> +	if (chip == adt7476 || chip == adt7490) {
> +		conf_copy = *config4;
> +
> +		modify_config(client, "bypass-attenuator-in0", &conf_copy, 4);
> +		modify_config(client, "bypass-attenuator-in1", &conf_copy, 5);
> +		modify_config(client, "bypass-attenuator-in3", &conf_copy, 6);
> +		modify_config(client, "bypass-attenuator-in4", &conf_copy, 7);
> +
> +		ret = i2c_smbus_write_byte_data(client, REG_CONFIG4,
> +			conf_copy);
> +		if (ret < 0)
> +			return ret;
> +
> +		*config4 = conf_copy;
> +	} else if (chip == adt7473 || chip == adt7475) {
> +		conf_copy = *config2;
> +
> +		modify_config(client, "bypass-attenuator-in1", &conf_copy, 5);
> +
> +		ret = i2c_smbus_write_byte_data(client, REG_CONFIG2,
> +			conf_copy);
> +		if (ret < 0)
> +			return ret;
> +
> +		*config2 = conf_copy;
> +	}
> +
> +	return 0;
> +}
> +
>   static int adt7475_probe(struct i2c_client *client,
>   			 const struct i2c_device_id *id)
>   {
> @@ -1546,6 +1611,9 @@ static int adt7475_probe(struct i2c_client *client,
>   
>   	/* Voltage attenuators can be bypassed, globally or individually */
>   	config2 = adt7475_read(REG_CONFIG2);
> +	if (load_attenuators(client, chip, &config2, &(data->config4)) < 0)
> +		dev_warn(&client->dev, "Error setting bypass attenuators\n");
> +
>   	if (config2 & CONFIG2_ATTN) {
>   		data->bypass_attn = (0x3 << 3) | 0x3;
>   	} else {
> 
CHECK: Alignment should match open parenthesis
#45: FILE: drivers/hwmon/adt7475.c:1467:
+static void modify_config(const struct i2c_client *client, char *property,
+				u8 *config, u8 bit_index)

CHECK: Alignment should match open parenthesis
#68: FILE: drivers/hwmon/adt7475.c:1490:
+static int load_attenuators(const struct i2c_client *client, int chip,
+				u8 *config2, u8 *config4)

CHECK: Alignment should match open parenthesis
#82: FILE: drivers/hwmon/adt7475.c:1504:
+		ret = i2c_smbus_write_byte_data(client, REG_CONFIG4,
+			conf_copy);

CHECK: Alignment should match open parenthesis
#93: FILE: drivers/hwmon/adt7475.c:1515:
+		ret = i2c_smbus_write_byte_data(client, REG_CONFIG2,
+			conf_copy);

CHECK: Unnecessary parentheses around data->config4
#110: FILE: drivers/hwmon/adt7475.c:1614:
+	if (load_attenuators(client, chip, &config2, &(data->config4)) < 0)

None of those is beneficial. Please fix.

Thanks,
Guenter


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH v5 2/2] dt-bindings: hwmon: (adt7475) Added missing adt7475 doccumentation
  2020-01-23 22:05 ` [PATCH v5 2/2] dt-bindings: hwmon: (adt7475) Added missing adt7475 doccumentation Logan Shaw
@ 2020-01-25 23:09   ` Guenter Roeck
  0 siblings, 0 replies; 5+ messages in thread
From: Guenter Roeck @ 2020-01-25 23:09 UTC (permalink / raw)
  To: Logan Shaw
  Cc: jdelvare, robh+dt, linux-hwmon, linux-kernel, devicetree,
	Joshua.Scott, Chris.Packham

On Fri, Jan 24, 2020 at 11:05:33AM +1300, Logan Shaw wrote:
> Added a new file documenting the adt7475 devicetree and added the four
> new properties to it.
> 
> Signed-off-by: Logan Shaw <logan.shaw@alliedtelesis.co.nz>

Subject: s/doccumentation/documentation/

Guenter

> ---
> ---
>  .../devicetree/bindings/hwmon/adt7475.yaml    | 95 +++++++++++++++++++
>  1 file changed, 95 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/hwmon/adt7475.yaml
> 
> diff --git a/Documentation/devicetree/bindings/hwmon/adt7475.yaml b/Documentation/devicetree/bindings/hwmon/adt7475.yaml
> new file mode 100644
> index 000000000000..450da5e66e07
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/adt7475.yaml
> @@ -0,0 +1,95 @@
> +# SPDX-License-Identifier: GPL-2.0
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/adt7475.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: ADT7475 hwmon sensor
> +
> +maintainers:
> +  - Jean Delvare <jdelvare@suse.com>
> +
> +description: |
> +  The ADT7473, ADT7475, ADT7476, and ADT7490 are thermal monitors and multiple
> +  PWN fan controllers.
> +
> +  They support monitoring and controlling up to four fans (the ADT7490 can only
> +  control up to three). They support reading a single on chip temperature
> +  sensor and two off chip temperature sensors (the ADT7490 additionally
> +  supports measuring up to three current external temperature sensors with
> +  series resistance cancellation (SRC)).
> +
> +  Datasheets:
> +  https://www.onsemi.com/pub/Collateral/ADT7473-D.PDF
> +  https://www.onsemi.com/pub/Collateral/ADT7475-D.PDF
> +  https://www.onsemi.com/pub/Collateral/ADT7476-D.PDF
> +  https://www.onsemi.com/pub/Collateral/ADT7490-D.PDF
> +
> +  Description taken from omsemiconductors specification sheets, with minor
> +  rephrasing.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - adi,adt7473
> +      - adi,adt7475
> +      - adi,adt7476
> +      - adi,adt7490
> +
> +  reg:
> +    maxItems: 1
> +
> +  bypass-attenuator-in0:
> +    description: |
> +      Configures bypassing the individual voltage input
> +      attenuator, on in0. This is supported on the ADT7476 and ADT7490.
> +      If set to a non-zero integer the attenuator is bypassed, if set to
> +      zero the attenuator is not bypassed. If the property is absent then
> +      the config register is not modified.
> +    maxItems: 1
> +
> +  bypass-attenuator-in1:
> +    description: |
> +      Configures bypassing the individual voltage input
> +      attenuator, on in1. This is supported on the ADT7473, ADT7475,
> +      ADT7476 and ADT7490. If set to a non-zero integer the attenuator
> +      is bypassed, if set to zero the attenuator is not bypassed. If the
> +      property is absent then the config register is not modified.
> +    maxItems: 1
> +
> +  bypass-attenuator-in3:
> +    description: |
> +      Configures bypassing the individual voltage input
> +      attenuator, on in3. This is supported on the ADT7476 and ADT7490.
> +      If set to a non-zero integer the attenuator is bypassed, if set to
> +      zero the attenuator is not bypassed. If the property is absent then
> +      the config register is not modified.
> +    maxItems: 1
> +
> +  bypass-attenuator-in4:
> +    description: |
> +      Configures bypassing the individual voltage input
> +      attenuator, on in4. This is supported on the ADT7476 and ADT7490.
> +      If set to a non-zero integer the attenuator is bypassed, if set to
> +      zero the attenuator is not bypassed. If the property is absent then
> +      the config register is not modified.
> +    maxItems: 1
> +
> +required:
> +  - compatible
> +  - reg
> +
> +examples:
> +  - |
> +    i2c {
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +
> +      hwmon@2e {
> +        compatible = "adi,adt7476";
> +        reg = <0x2e>;
> +        bypass-attenuator-in0 = <1>;
> +        bypass-attenuator-in1 = <0>;
> +      };
> +    };
> +...

^ permalink raw reply	[flat|nested] 5+ messages in thread

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Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-01-23 22:05 [PATCH v5 0/2] hwmon: (adt7475) Added attenuator bypass support Logan Shaw
2020-01-23 22:05 ` [PATCH v5 1/2] " Logan Shaw
2020-01-24  4:55   ` Guenter Roeck
2020-01-23 22:05 ` [PATCH v5 2/2] dt-bindings: hwmon: (adt7475) Added missing adt7475 doccumentation Logan Shaw
2020-01-25 23:09   ` Guenter Roeck

Linux-Hwmon Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-hwmon/0 linux-hwmon/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-hwmon linux-hwmon/ https://lore.kernel.org/linux-hwmon \
		linux-hwmon@vger.kernel.org
	public-inbox-index linux-hwmon

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-hwmon


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git