| Message ID | 1424878462-15511-7-git-send-email-l.majewski@samsung.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
Hey Lukasz, On Wed, Feb 25, 2015 at 04:34:22PM +0100, Lukasz Majewski wrote: > The PWM FAN device can now be used as a thermal cooling device. Necessary > infrastructure has been added in this commit. > > Signed-off-by: Lukasz Majewski <l.majewski@samsung.com> > --- > Changes for v2: > - Replace pwm_fan_cooling_states with pwm_fan_cooling_levels > - Update ctx->pwm_fan_state when correct data from device tree is available > - Using therma_cdev_update() when thermal is ready for controlling the fan > Changes for v3: > - Rename patch heading > - pwm_fan_of_get_cooling_data() now returns -EINVAL when no "cooling-levels" > property defined > - register of cooling device only when proper cooling data is present > Changes for v4: > - None > Changes for v5: > - Check for IS_ENABLED(CONFIG_THERMAL) has been added to prevent from > executing thermal_* specific functions > --- > drivers/hwmon/pwm-fan.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 82 insertions(+), 1 deletion(-) > > diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c > index e6ed353..2c1a8f0 100644 > --- a/drivers/hwmon/pwm-fan.c > +++ b/drivers/hwmon/pwm-fan.c > @@ -24,6 +24,7 @@ > #include <linux/platform_device.h> > #include <linux/pwm.h> > #include <linux/sysfs.h> > +#include <linux/thermal.h> > > #define MAX_PWM 255 > > @@ -68,6 +69,17 @@ exit_set_pwm_err: > return ret; > } > > +static void pwm_fan_update_state(struct pwm_fan_ctx *ctx, unsigned long pwm) > +{ > + int i; > + > + for (i = 0; i < ctx->pwm_fan_max_state; ++i) > + if (pwm < ctx->pwm_fan_cooling_levels[i + 1]) > + break; > + > + ctx->pwm_fan_state = i; > +} > + > static ssize_t set_pwm(struct device *dev, struct device_attribute *attr, > const char *buf, size_t count) > { > @@ -82,6 +94,7 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *attr, > if (ret) > return ret; > > + pwm_fan_update_state(ctx, pwm); > return count; > } > > @@ -103,6 +116,59 @@ static struct attribute *pwm_fan_attrs[] = { > > ATTRIBUTE_GROUPS(pwm_fan); > > +/* thermal cooling device callbacks */ > +static int pwm_fan_get_max_state(struct thermal_cooling_device *cdev, > + unsigned long *state) > +{ > + struct pwm_fan_ctx *ctx = cdev->devdata; > + Why this call back is the only one you didn't add a check for ctx == NULL? > + *state = ctx->pwm_fan_max_state; > + > + return 0; > +} > + > +static int pwm_fan_get_cur_state(struct thermal_cooling_device *cdev, > + unsigned long *state) > +{ > + struct pwm_fan_ctx *ctx = cdev->devdata; > + > + if (!ctx) > + return -EINVAL; > + > + *state = ctx->pwm_fan_state; > + > + return 0; > +} > + > +static int > +pwm_fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state) > +{ > + struct pwm_fan_ctx *ctx = cdev->devdata; > + int ret; > + > + if (!ctx || (state > ctx->pwm_fan_max_state)) > + return -EINVAL; > + > + if (state == ctx->pwm_fan_state) > + return 0; > + > + ret = __set_pwm(ctx, ctx->pwm_fan_cooling_levels[state]); > + if (ret) { > + dev_err(&cdev->device, "Cannot set pwm!\n"); > + return ret; > + } > + > + ctx->pwm_fan_state = state; > + > + return ret; > +} > + > +static const struct thermal_cooling_device_ops pwm_fan_cooling_ops = { > + .get_max_state = pwm_fan_get_max_state, > + .get_cur_state = pwm_fan_get_cur_state, > + .set_cur_state = pwm_fan_set_cur_state, > +}; > + > int pwm_fan_of_get_cooling_data(struct device *dev, struct pwm_fan_ctx *ctx) > { > struct device_node *np = dev->of_node; > @@ -145,8 +211,9 @@ int pwm_fan_of_get_cooling_data(struct device *dev, struct pwm_fan_ctx *ctx) > > static int pwm_fan_probe(struct platform_device *pdev) > { > - struct device *hwmon; > + struct thermal_cooling_device *cdev; > struct pwm_fan_ctx *ctx; > + struct device *hwmon; > int duty_cycle; > int ret; > > @@ -193,6 +260,20 @@ static int pwm_fan_probe(struct platform_device *pdev) > if (ret) > return ret; > > + ctx->pwm_fan_state = ctx->pwm_fan_max_state; > + if (IS_ENABLED(CONFIG_THERMAL)) { > + cdev = thermal_of_cooling_device_register(pdev->dev.of_node, > + "pwm-fan", ctx, > + &pwm_fan_cooling_ops); I know this is a PITA, but thermal subsystem still does not use devm based helpers. That means, you need to be old school and unregister the device yourself. Please add the cdev to ctx structure: + ctx->cdev = cdev; and add a call for: thermal_cooling_device_unregister(ctx->cdev); in static int pwm_fan_remove(struct platform_device *pdev) despite the above two minor issues, you may add my Acked-by: Eduardo Valentin <edubezval@gmail.com> > + if (IS_ERR(cdev)) { > + dev_err(&pdev->dev, > + "Failed to register pwm-fan as cooling device"); > + pwm_disable(ctx->pwm); > + return PTR_ERR(cdev); > + } > + thermal_cdev_update(cdev); > + } > + > return 0; > } > > -- > 2.0.0.rc2 >
diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c index e6ed353..2c1a8f0 100644 --- a/drivers/hwmon/pwm-fan.c +++ b/drivers/hwmon/pwm-fan.c @@ -24,6 +24,7 @@ #include <linux/platform_device.h> #include <linux/pwm.h> #include <linux/sysfs.h> +#include <linux/thermal.h> #define MAX_PWM 255 @@ -68,6 +69,17 @@ exit_set_pwm_err: return ret; } +static void pwm_fan_update_state(struct pwm_fan_ctx *ctx, unsigned long pwm) +{ + int i; + + for (i = 0; i < ctx->pwm_fan_max_state; ++i) + if (pwm < ctx->pwm_fan_cooling_levels[i + 1]) + break; + + ctx->pwm_fan_state = i; +} + static ssize_t set_pwm(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { @@ -82,6 +94,7 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *attr, if (ret) return ret; + pwm_fan_update_state(ctx, pwm); return count; } @@ -103,6 +116,59 @@ static struct attribute *pwm_fan_attrs[] = { ATTRIBUTE_GROUPS(pwm_fan); +/* thermal cooling device callbacks */ +static int pwm_fan_get_max_state(struct thermal_cooling_device *cdev, + unsigned long *state) +{ + struct pwm_fan_ctx *ctx = cdev->devdata; + + *state = ctx->pwm_fan_max_state; + + return 0; +} + +static int pwm_fan_get_cur_state(struct thermal_cooling_device *cdev, + unsigned long *state) +{ + struct pwm_fan_ctx *ctx = cdev->devdata; + + if (!ctx) + return -EINVAL; + + *state = ctx->pwm_fan_state; + + return 0; +} + +static int +pwm_fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state) +{ + struct pwm_fan_ctx *ctx = cdev->devdata; + int ret; + + if (!ctx || (state > ctx->pwm_fan_max_state)) + return -EINVAL; + + if (state == ctx->pwm_fan_state) + return 0; + + ret = __set_pwm(ctx, ctx->pwm_fan_cooling_levels[state]); + if (ret) { + dev_err(&cdev->device, "Cannot set pwm!\n"); + return ret; + } + + ctx->pwm_fan_state = state; + + return ret; +} + +static const struct thermal_cooling_device_ops pwm_fan_cooling_ops = { + .get_max_state = pwm_fan_get_max_state, + .get_cur_state = pwm_fan_get_cur_state, + .set_cur_state = pwm_fan_set_cur_state, +}; + int pwm_fan_of_get_cooling_data(struct device *dev, struct pwm_fan_ctx *ctx) { struct device_node *np = dev->of_node; @@ -145,8 +211,9 @@ int pwm_fan_of_get_cooling_data(struct device *dev, struct pwm_fan_ctx *ctx) static int pwm_fan_probe(struct platform_device *pdev) { - struct device *hwmon; + struct thermal_cooling_device *cdev; struct pwm_fan_ctx *ctx; + struct device *hwmon; int duty_cycle; int ret; @@ -193,6 +260,20 @@ static int pwm_fan_probe(struct platform_device *pdev) if (ret) return ret; + ctx->pwm_fan_state = ctx->pwm_fan_max_state; + if (IS_ENABLED(CONFIG_THERMAL)) { + cdev = thermal_of_cooling_device_register(pdev->dev.of_node, + "pwm-fan", ctx, + &pwm_fan_cooling_ops); + if (IS_ERR(cdev)) { + dev_err(&pdev->dev, + "Failed to register pwm-fan as cooling device"); + pwm_disable(ctx->pwm); + return PTR_ERR(cdev); + } + thermal_cdev_update(cdev); + } + return 0; }
The PWM FAN device can now be used as a thermal cooling device. Necessary infrastructure has been added in this commit. Signed-off-by: Lukasz Majewski <l.majewski@samsung.com> --- Changes for v2: - Replace pwm_fan_cooling_states with pwm_fan_cooling_levels - Update ctx->pwm_fan_state when correct data from device tree is available - Using therma_cdev_update() when thermal is ready for controlling the fan Changes for v3: - Rename patch heading - pwm_fan_of_get_cooling_data() now returns -EINVAL when no "cooling-levels" property defined - register of cooling device only when proper cooling data is present Changes for v4: - None Changes for v5: - Check for IS_ENABLED(CONFIG_THERMAL) has been added to prevent from executing thermal_* specific functions --- drivers/hwmon/pwm-fan.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 82 insertions(+), 1 deletion(-)