[patch v5] hwmon: (aspeed-pwm-tacho) cooling device support.
Joel Stanley
joel at jms.id.au
Thu Jul 27 11:36:13 AEST 2017
On Thu, Jul 27, 2017 at 12:22 AM, Mykola Kostenok
<c_mykolak at mellanox.com> wrote:
> Add support in aspeed-pwm-tacho driver for cooling device creation.
> This cooling device could be bound to a thermal zone
> for the thermal control. Device will appear in /sys/class/thermal
> folder as cooling_deviceX. Then it could be bound to particular
> thermal zones. Allow specification of the cooling levels
> vector - PWM duty cycle values in a range from 0 to 255
> which correspond to thermal cooling states.
>
> Signed-off-by: Mykola Kostenok <c_mykolak at mellanox.com>
Looks good.
Reviewed-by: Joel Stanley <joel at jms.id.au>
>
> v1 -> v2:
> - Remove device tree binding file from the patch.
> - Move of_node_put out of cycle because of_get_next_child
> already do of_put_node on previous child.
>
> v2 -> v3:
> Pointed out by Rob Herring:
> - Put cooling-levels under fan subnodes.
>
> v3 -> v4:
> Pointed out by Joel Stanley:
> - Move patch history after Signoff.
> - Remove unnecessary type cast.
> - Use array instead of pointers for colling_levels.
> - Rename num_level to num_levels.
> - Use local variable to make function easier to read.
> - Drop unnesesary sizeof(u8).
> - Use IS_ERR instead of PTR_ERR_OR_ZERO.
>
> v4 -> v5:
> Pointed out by Joel Stanley:
> - Use snprintf to fill cdev->name[16].
> ---
> drivers/hwmon/aspeed-pwm-tacho.c | 117 ++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 115 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hwmon/aspeed-pwm-tacho.c b/drivers/hwmon/aspeed-pwm-tacho.c
> index ddfe66b..049e4eb 100644
> --- a/drivers/hwmon/aspeed-pwm-tacho.c
> +++ b/drivers/hwmon/aspeed-pwm-tacho.c
> @@ -20,6 +20,7 @@
> #include <linux/platform_device.h>
> #include <linux/sysfs.h>
> #include <linux/regmap.h>
> +#include <linux/thermal.h>
>
> /* ASPEED PWM & FAN Tach Register Definition */
> #define ASPEED_PTCR_CTRL 0x00
> @@ -166,6 +167,18 @@
> /* How long we sleep in us while waiting for an RPM result. */
> #define ASPEED_RPM_STATUS_SLEEP_USEC 500
>
> +#define MAX_CDEV_NAME_LEN 16
> +
> +struct aspeed_cooling_device {
> + char name[16];
> + struct aspeed_pwm_tacho_data *priv;
> + struct thermal_cooling_device *tcdev;
> + int pwm_port;
> + u8 *cooling_levels;
> + u8 max_state;
> + u8 cur_state;
> +};
> +
> struct aspeed_pwm_tacho_data {
> struct regmap *regmap;
> unsigned long clk_freq;
> @@ -180,6 +193,7 @@ struct aspeed_pwm_tacho_data {
> u8 pwm_port_type[8];
> u8 pwm_port_fan_ctrl[8];
> u8 fan_tach_ch_source[16];
> + struct aspeed_cooling_device *cdev[8];
> const struct attribute_group *groups[3];
> };
>
> @@ -765,6 +779,94 @@ static void aspeed_create_fan_tach_channel(struct aspeed_pwm_tacho_data *priv,
> }
> }
>
> +static int
> +aspeed_pwm_cz_get_max_state(struct thermal_cooling_device *tcdev,
> + unsigned long *state)
> +{
> + struct aspeed_cooling_device *cdev = tcdev->devdata;
> +
> + *state = cdev->max_state;
> +
> + return 0;
> +}
> +
> +static int
> +aspeed_pwm_cz_get_cur_state(struct thermal_cooling_device *tcdev,
> + unsigned long *state)
> +{
> + struct aspeed_cooling_device *cdev = tcdev->devdata;
> +
> + *state = cdev->cur_state;
> +
> + return 0;
> +}
> +
> +static int
> +aspeed_pwm_cz_set_cur_state(struct thermal_cooling_device *tcdev,
> + unsigned long state)
> +{
> + struct aspeed_cooling_device *cdev = tcdev->devdata;
> +
> + if (state > cdev->max_state)
> + return -EINVAL;
> +
> + cdev->cur_state = state;
> + cdev->priv->pwm_port_fan_ctrl[cdev->pwm_port] =
> + cdev->cooling_levels[cdev->cur_state];
> + aspeed_set_pwm_port_fan_ctrl(cdev->priv, cdev->pwm_port,
> + cdev->cooling_levels[cdev->cur_state]);
> +
> + return 0;
> +}
> +
> +static const struct thermal_cooling_device_ops aspeed_pwm_cool_ops = {
> + .get_max_state = aspeed_pwm_cz_get_max_state,
> + .get_cur_state = aspeed_pwm_cz_get_cur_state,
> + .set_cur_state = aspeed_pwm_cz_set_cur_state,
> +};
> +
> +static int aspeed_create_pwm_cooling(struct device *dev,
> + struct device_node *child,
> + struct aspeed_pwm_tacho_data *priv,
> + u32 pwm_port, u8 num_levels)
> +{
> + int ret;
> + struct aspeed_cooling_device *cdev;
> +
> + cdev = devm_kzalloc(dev, sizeof(*cdev), GFP_KERNEL);
> +
> + if (!cdev)
> + return -ENOMEM;
> +
> + cdev->cooling_levels = devm_kzalloc(dev, num_levels, GFP_KERNEL);
> + if (!cdev->cooling_levels)
> + return -ENOMEM;
> +
> + cdev->max_state = num_levels - 1;
> + ret = of_property_read_u8_array(child, "cooling-levels",
> + cdev->cooling_levels,
> + num_levels);
> + if (ret) {
> + dev_err(dev, "Property 'cooling-levels' cannot be read.\n");
> + return ret;
> + }
> + snprintf(cdev->name, MAX_CDEV_NAME_LEN, "%s%d", child->name, pwm_port);
> +
> + cdev->tcdev = thermal_of_cooling_device_register(child,
> + cdev->name,
> + cdev,
> + &aspeed_pwm_cool_ops);
> + if (IS_ERR(cdev->tcdev))
> + return PTR_ERR(cdev->tcdev);
> +
> + cdev->priv = priv;
> + cdev->pwm_port = pwm_port;
> +
> + priv->cdev[pwm_port] = cdev;
> +
> + return 0;
> +}
> +
> static int aspeed_create_fan(struct device *dev,
> struct device_node *child,
> struct aspeed_pwm_tacho_data *priv)
> @@ -778,6 +880,15 @@ static int aspeed_create_fan(struct device *dev,
> return ret;
> aspeed_create_pwm_port(priv, (u8)pwm_port);
>
> + ret = of_property_count_u8_elems(child, "cooling-levels");
> +
> + if (ret > 0) {
> + ret = aspeed_create_pwm_cooling(dev, child, priv, pwm_port,
> + ret);
> + if (ret)
> + return ret;
> + }
> +
> count = of_property_count_u8_elems(child, "aspeed,fan-tach-ch");
> if (count < 1)
> return -EINVAL;
> @@ -834,10 +945,12 @@ static int aspeed_pwm_tacho_probe(struct platform_device *pdev)
>
> for_each_child_of_node(np, child) {
> ret = aspeed_create_fan(dev, child, priv);
> - of_node_put(child);
> - if (ret)
> + if (ret) {
> + of_node_put(child);
> return ret;
> + }
> }
> + of_node_put(child);
>
> priv->groups[0] = &pwm_dev_group;
> priv->groups[1] = &fan_dev_group;
> --
> 2.8.4
>
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