* Re: [PATCH v3] hwmon/max6650.c: Add devicetree support
2016-08-10 14:19 ` [PATCH v3] hwmon/max6650.c: Add devicetree support Mike Looijmans
@ 2016-08-11 14:43 ` Guenter Roeck
2016-08-12 18:26 ` Rob Herring
1 sibling, 0 replies; 3+ messages in thread
From: Guenter Roeck @ 2016-08-11 14:43 UTC (permalink / raw)
To: Mike Looijmans, lm-sensors, devicetree
Cc: linux-kernel, linux-hwmon@vger.kernel.org
On 08/10/2016 07:19 AM, Mike Looijmans wrote:
> Parse devicetree parameters for voltage and prescaler setting. This allows
> using multiple max6550 devices with varying settings, and also makes it
> possible to instantiate and configure the device using devicetree.
>
For the subject: Please use "hwmon: (max6650) Add devicetree support"
> Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
> ---
> v3: Resubmit because mailing lists bounced
It bounced because you sent to the old hwmon mailing list which is at best
unreliable. Please send future versions to linux-hwmon@vger.kernel.org.
> Fix style errors as reported by checkpatch.pl
> Fix bug in DT parsing of fan-prescale
> v2: Add devicetree binding documentation
> Code changes as suggested by Guenter
> Reduce log info, output only a single line
>
> .../devicetree/bindings/hwmon/max6650.txt | 20 ++++++++++++++++
Please submit the devicetree properties as separate patch.
> drivers/hwmon/max6650.c | 28 +++++++++++++---------
> 2 files changed, 37 insertions(+), 11 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/hwmon/max6650.txt
>
> diff --git a/Documentation/devicetree/bindings/hwmon/max6650.txt b/Documentation/devicetree/bindings/hwmon/max6650.txt
> new file mode 100644
> index 0000000..89d87c6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/max6650.txt
> @@ -0,0 +1,20 @@
> +Bindings for MAX6651 and MAX6650 I2C fan controllers
> +
> +Required properties:
> +- compatible : One of "max6650" or "max6651"
> +- reg : I2C address
> +
> +Optional properties:
> +- fan-voltage : The supply voltage of the fan. Valid values are 5 and 12.
> + Default is to use the chip's current setting.
> +- fan-prescale : Pre-scaling value as per datasheet. Valid are 1, 2, 4, 8, 16.
> + Default is to use the chip's current setting.
> +
> +
One empty line is sufficient.
> +Example:
> + fan-max6650: max6650@1b {
> + reg = <0x1b>;
> + compatible = "max6650";
> + fan-voltage = <12>;
> + fan-prescale = <4>;
> + };
> diff --git a/drivers/hwmon/max6650.c b/drivers/hwmon/max6650.c
> index 162a520..56a6c87 100644
> --- a/drivers/hwmon/max6650.c
> +++ b/drivers/hwmon/max6650.c
> @@ -41,14 +41,14 @@
> #include <linux/err.h>
>
> /*
> - * Insmod parameters
> + * Insmod parameters (for backward compatibility)
That doesn't add any value.
> */
>
> /* fan_voltage: 5=5V fan, 12=12V fan, 0=don't change */
> static int fan_voltage;
> /* prescaler: Possible values are 1, 2, 4, 8, 16 or 0 for don't change */
> static int prescaler;
> -/* clock: The clock frequency of the chip the driver should assume */
> +/* clock: The clock frequency of the chip (max6651 can be clocked externally) */
> static int clock = 254000;
>
> module_param(fan_voltage, int, S_IRUGO);
> @@ -566,6 +566,15 @@ static int max6650_init_client(struct max6650_data *data,
> struct device *dev = &client->dev;
> int config;
> int err = -EIO;
> + u32 voltage;
> + u32 prescale;
> +
> + if (of_property_read_u32(client->dev.of_node, "fan-voltage",
> + &voltage))
> + voltage = fan_voltage;
> + if (of_property_read_u32(client->dev.of_node, "fan-prescale",
> + &prescale))
> + prescale = prescaler;
>
> config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG);
>
> @@ -574,7 +583,7 @@ static int max6650_init_client(struct max6650_data *data,
> return err;
> }
>
> - switch (fan_voltage) {
> + switch (voltage) {
> case 0:
> break;
> case 5:
> @@ -584,14 +593,10 @@ static int max6650_init_client(struct max6650_data *data,
> config |= MAX6650_CFG_V12;
> break;
> default:
> - dev_err(dev, "illegal value for fan_voltage (%d)\n",
> - fan_voltage);
> + dev_err(dev, "illegal value for fan_voltage (%d)\n", voltage);
> }
>
> - dev_info(dev, "Fan voltage is set to %dV.\n",
> - (config & MAX6650_CFG_V12) ? 12 : 5);
> -
> - switch (prescaler) {
> + switch (prescale) {
> case 0:
> break;
> case 1:
> @@ -614,10 +619,11 @@ static int max6650_init_client(struct max6650_data *data,
> | MAX6650_CFG_PRESCALER_16;
> break;
> default:
> - dev_err(dev, "illegal value for prescaler (%d)\n", prescaler);
> + dev_err(dev, "illegal value for prescaler (%d)\n", prescale);
Side note: Those errors should really result in an -EINVAL return.
Separate patch, though.
> }
>
> - dev_info(dev, "Prescaler is set to %d.\n",
> + dev_info(dev, "Fan voltage: %dV, prescaler: %d.\n",
> + (config & MAX6650_CFG_V12) ? 12 : 5,
> 1 << (config & MAX6650_CFG_PRESCALER_MASK));
>
> /*
>
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH v3] hwmon/max6650.c: Add devicetree support
2016-08-10 14:19 ` [PATCH v3] hwmon/max6650.c: Add devicetree support Mike Looijmans
2016-08-11 14:43 ` Guenter Roeck
@ 2016-08-12 18:26 ` Rob Herring
1 sibling, 0 replies; 3+ messages in thread
From: Rob Herring @ 2016-08-12 18:26 UTC (permalink / raw)
To: Mike Looijmans; +Cc: lm-sensors, devicetree, linux, linux-kernel
On Wed, Aug 10, 2016 at 04:19:47PM +0200, Mike Looijmans wrote:
> Parse devicetree parameters for voltage and prescaler setting. This allows
> using multiple max6550 devices with varying settings, and also makes it
> possible to instantiate and configure the device using devicetree.
>
> Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
> ---
> v3: Resubmit because mailing lists bounced
> Fix style errors as reported by checkpatch.pl
> Fix bug in DT parsing of fan-prescale
> v2: Add devicetree binding documentation
> Code changes as suggested by Guenter
> Reduce log info, output only a single line
>
> .../devicetree/bindings/hwmon/max6650.txt | 20 ++++++++++++++++
> drivers/hwmon/max6650.c | 28 +++++++++++++---------
> 2 files changed, 37 insertions(+), 11 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/hwmon/max6650.txt
>
> diff --git a/Documentation/devicetree/bindings/hwmon/max6650.txt b/Documentation/devicetree/bindings/hwmon/max6650.txt
> new file mode 100644
> index 0000000..89d87c6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/max6650.txt
> @@ -0,0 +1,20 @@
> +Bindings for MAX6651 and MAX6650 I2C fan controllers
> +
> +Required properties:
> +- compatible : One of "max6650" or "max6651"
Needs a vendor prefix.
> +- reg : I2C address
> +
> +Optional properties:
> +- fan-voltage : The supply voltage of the fan. Valid values are 5 and 12.
This is in volts? Please use microvolt and the standard unit suffix as
found in property-units.txt.
> + Default is to use the chip's current setting.
> +- fan-prescale : Pre-scaling value as per datasheet. Valid are 1, 2, 4, 8, 16.
> + Default is to use the chip's current setting.
Add a vendor prefix here.
> +
> +
> +Example:
> + fan-max6650: max6650@1b {
> + reg = <0x1b>;
> + compatible = "max6650";
> + fan-voltage = <12>;
> + fan-prescale = <4>;
> + };
^ permalink raw reply [flat|nested] 3+ messages in thread