[patch v1] hwmon: (aspeed-pwm-tacho) cooling device support.
Guenter Roeck
linux at roeck-us.net
Sat Jul 8 04:08:44 AEST 2017
On Thu, Jul 06, 2017 at 05:23:38PM +0300, Mykola Kostenok 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>
> ---
> .../devicetree/bindings/hwmon/aspeed-pwm-tacho.txt | 52 ++++++--
You'll need devicetree maintainer approval for any devicetree
changes.
> drivers/hwmon/aspeed-pwm-tacho.c | 141 ++++++++++++++++++++-
> 2 files changed, 179 insertions(+), 14 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt b/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt
> index cf44605..293a994 100644
> --- a/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt
> +++ b/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt
> @@ -23,9 +23,14 @@ Required properties for pwm-tacho node:
> - clocks : a fixed clock providing input clock frequency(PWM
> and Fan Tach clock)
>
> -fan subnode format:
> +tach-channels subnode format:
I don't like the notion of renaming "fan subnode" to "tach-channels
subnode". To me that is just a personal preference. Tomorrow I might
get another patch changing it back or changing it to something else.
But, as mentioned above, you'll need DT maintaier approval for those
changes in the first place.
Guenter
> ===================
> -Under fan subnode there can upto 8 child nodes, with each child node
> +Required properties for tach-channels node:
> +- #address-cells : should be 1.
> +
> +- #size-cells : should be 0.
> +
> +Under tach-channels subnode there can be upto 8 child nodes, with each child node
> representing a fan. If there are 8 fans each fan can have one PWM port and
> one/two Fan tach inputs.
>
> @@ -39,6 +44,22 @@ Required properties for each child node:
> Fan tach channel 0 and 15 indicating Fan tach channel 15.
> Atleast one Fan tach input channel is required.
>
> +pwm-channels subnode format:
> +Under pwm-channels subnode there can be pwm child nodes.
> +Required properties for tach-channels node:
> +- #address-cells : should be 1.
> +
> +- #size-cells : should be 0.
> +
> +- #cooling-cells : should be 2;
> +
> +pwm subnode format:
> +- reg : should be <0x00>.
> +
> +- cooling-levels : PWM duty cycle values in a range from 0 to 255
> + which correspond to thermal cooling states.
> +
> +
> Examples:
>
> pwm_tacho_fixed_clk: fixedclk {
> @@ -55,14 +76,25 @@ pwm_tacho: pwmtachocontroller at 1e786000 {
> clocks = <&pwm_tacho_fixed_clk>;
> pinctrl-names = "default";
> pinctrl-0 = <&pinctrl_pwm0_default &pinctrl_pwm1_default>;
> -
> - fan at 0 {
> - reg = <0x00>;
> - aspeed,fan-tach-ch = /bits/ 8 <0x00>;
> + tach-channels {
> + #address-cells = <1>;
> + #size-cells = <0>;
> + fan at 0 {
> + reg = <0x00>;
> + aspeed,fan-tach-ch = /bits/ 8 <0x00>;
> + };
> + fan at 1 {
> + reg = <0x01>;
> + aspeed,fan-tach-ch = /bits/ 8 <0x01 0x02>;
> + };
> };
> -
> - fan at 1 {
> - reg = <0x01>;
> - aspeed,fan-tach-ch = /bits/ 8 <0x01 0x02>;
> + pwm-channels {
> + #address-cells = <1>;
> + #size-cells = <0>;
> + #cooling-cells = <2>;
> + pwm at 0 {
> + reg = <0x00>;
> + cooling-levels = /bits/ 8 <125 151 177 203 229 255>;
> + };
> };
> };
> diff --git a/drivers/hwmon/aspeed-pwm-tacho.c b/drivers/hwmon/aspeed-pwm-tacho.c
> index ddfe66b..c10a37e 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 +167,16 @@
> /* How long we sleep in us while waiting for an RPM result. */
> #define ASPEED_RPM_STATUS_SLEEP_USEC 500
>
> +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 +191,7 @@ 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];
> };
>
> @@ -794,10 +806,111 @@ static int aspeed_create_fan(struct device *dev,
> return 0;
> }
>
> +static int
> +aspeed_pwm_cz_get_max_state(struct thermal_cooling_device *tcdev,
> + unsigned long *state)
> +{
> + struct aspeed_cooling_device *cdev =
> + (struct aspeed_cooling_device *)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 =
> + (struct aspeed_cooling_device *)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 =
> + (struct aspeed_cooling_device *)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;
> + int ret;
> +
> + ret = of_property_read_u32(child, "reg", &pwm_port);
> + if (ret)
> + return ret;
> +
> + ret = of_property_count_u8_elems(child, "cooling-levels");
> + if (ret <= 0) {
> + dev_err(dev, "Wrong cooling-levels data.\n");
> + return -EINVAL;
> + }
> +
> + priv->cdev[pwm_port] = devm_kzalloc(dev, sizeof(*priv->cdev[pwm_port]),
> + GFP_KERNEL);
> + if (!priv->cdev[pwm_port])
> + return -ENOMEM;
> +
> + priv->cdev[pwm_port]->cooling_levels = devm_kzalloc(dev, ret *
> + sizeof(u8),
> + GFP_KERNEL);
> + if (!priv->cdev[pwm_port]->cooling_levels)
> + return -ENOMEM;
> +
> + priv->cdev[pwm_port]->max_state = ret - 1;
> + ret = of_property_read_u8_array(child, "cooling-levels",
> + priv->cdev[pwm_port]->cooling_levels,
> + ret);
> + if (ret) {
> + dev_err(dev, "Property 'cooling-levels' cannot be read.\n");
> + return ret;
> + }
> +
> + sprintf(priv->cdev[pwm_port]->name, "%s%d", child->name, pwm_port);
> + priv->cdev[pwm_port]->tcdev = thermal_of_cooling_device_register(child,
> + priv->cdev[pwm_port]->name,
> + priv->cdev[pwm_port],
> + &aspeed_pwm_cool_ops);
> + if (PTR_ERR_OR_ZERO(priv->cdev[pwm_port]->tcdev))
> + return PTR_ERR(priv->cdev[pwm_port]->tcdev);
> +
> + priv->cdev[pwm_port]->priv = priv;
> + priv->cdev[pwm_port]->pwm_port = pwm_port;
> +
> + return 0;
> +}
> +
> static int aspeed_pwm_tacho_probe(struct platform_device *pdev)
> {
> struct device *dev = &pdev->dev;
> - struct device_node *np, *child;
> + struct device_node *np, *child, *grandchild;
> struct aspeed_pwm_tacho_data *priv;
> void __iomem *regs;
> struct resource *res;
> @@ -833,10 +946,30 @@ static int aspeed_pwm_tacho_probe(struct platform_device *pdev)
> aspeed_create_type(priv);
>
> for_each_child_of_node(np, child) {
> - ret = aspeed_create_fan(dev, child, priv);
> + if (!of_node_cmp(child->name, "tach-channels")) {
> + for_each_child_of_node(child, grandchild) {
> + ret = aspeed_create_fan(dev, grandchild, priv);
> + of_node_put(grandchild);
> + if (ret) {
> + of_node_put(child);
> + return ret;
> + }
> + }
> + }
> +
> + if (!of_node_cmp(child->name, "pwm-channels")) {
> + for_each_child_of_node(child, grandchild) {
> + ret = aspeed_create_pwm_cooling(dev,
> + grandchild,
> + priv);
> + of_node_put(grandchild);
> + if (ret) {
> + of_node_put(child);
> + return ret;
> + }
> + }
> + }
> of_node_put(child);
> - if (ret)
> - return ret;
> }
>
> priv->groups[0] = &pwm_dev_group;
> --
> 2.8.4
>
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