2013-03-26 13:30:28

by Yuxuan Shui

Subject: [PATCH] Thermal: Don't resolve THERMAL_NO_LIMIT to max_state.

max_state may change at runtime, for example, when loading/unloading
cpufreq policy.

Signed-off-by: Yuxuan Shui <[email protected]>
---
drivers/thermal/step_wise.c | 11 ++++++++---
drivers/thermal/thermal_sys.c | 5 ++---
2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/drivers/thermal/step_wise.c b/drivers/thermal/step_wise.c
index 407cde3..2edb7e9 100644
--- a/drivers/thermal/step_wise.c
+++ b/drivers/thermal/step_wise.c
@@ -54,18 +54,23 @@ static unsigned long get_target_state(struct thermal_instance *instance,
{
struct thermal_cooling_device *cdev = instance->cdev;
unsigned long cur_state;
+ unsigned long max_state;
+ int upper;

cdev->ops->get_cur_state(cdev, &cur_state);
+ cdev->ops->get_max_state(cdev, &max_state);
+
+ upper = instance->upper == THERMAL_NO_LIMIT ? max_state : instance->upper;

switch (trend) {
case THERMAL_TREND_RAISING:
if (throttle)
- cur_state = cur_state < instance->upper ?
- (cur_state + 1) : instance->upper;
+ cur_state = cur_state < upper ?
+ (cur_state + 1) : upper;
break;
case THERMAL_TREND_RAISE_FULL:
if (throttle)
- cur_state = instance->upper;
+ cur_state = upper;
break;
case THERMAL_TREND_DROPPING:
if (cur_state == instance->lower) {
diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c
index 5b7863a..f02e4d4 100644
--- a/drivers/thermal/thermal_sys.c
+++ b/drivers/thermal/thermal_sys.c
@@ -1134,11 +1134,10 @@ int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,

cdev->ops->get_max_state(cdev, &max_state);

- /* lower default 0, upper default max_state */
+ /* lower default 0 */
lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
- upper = upper == THERMAL_NO_LIMIT ? max_state : upper;

- if (lower > upper || upper > max_state)
+ if (lower > upper || (upper != THERMAL_NO_LIMIT && upper > max_state))
return -EINVAL;

dev =
--
1.8.2

2013-04-12 01:38:35

by Zhang, Rui

Subject: Re: [PATCH] Thermal: Don't resolve THERMAL_NO_LIMIT to max_state.

On Tue, 2013-03-26 at 21:29 +0800, Yuxuan Shui wrote:
> max_state may change at runtime, for example, when loading/unloading
> cpufreq policy.
>
this seems to be a problem that we have not covered yet.

when loading/unloading the cpufreq policy, the cpufreq_frequency_table
will be changed as well, right?
what if we want to use p4 for trip point 2, and then there are only two
valid entries after reloading cpufreq policy?

To me, the real thing we missed here is a mechanism for dynamic
binding.

thanks,
rui

> Signed-off-by: Yuxuan Shui <[email protected]>
> ---
> drivers/thermal/step_wise.c | 11 ++++++++---
> drivers/thermal/thermal_sys.c | 5 ++---
> 2 files changed, 10 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/thermal/step_wise.c b/drivers/thermal/step_wise.c
> index 407cde3..2edb7e9 100644
> --- a/drivers/thermal/step_wise.c
> +++ b/drivers/thermal/step_wise.c
> @@ -54,18 +54,23 @@ static unsigned long get_target_state(struct thermal_instance *instance,
> {
> struct thermal_cooling_device *cdev = instance->cdev;
> unsigned long cur_state;
> + unsigned long max_state;
> + int upper;
>
> cdev->ops->get_cur_state(cdev, &cur_state);
> + cdev->ops->get_max_state(cdev, &max_state);
> +
> + upper = instance->upper == THERMAL_NO_LIMIT ? max_state : instance->upper;
>
> switch (trend) {
> case THERMAL_TREND_RAISING:
> if (throttle)
> - cur_state = cur_state < instance->upper ?
> - (cur_state + 1) : instance->upper;
> + cur_state = cur_state < upper ?
> + (cur_state + 1) : upper;
> break;
> case THERMAL_TREND_RAISE_FULL:
> if (throttle)
> - cur_state = instance->upper;
> + cur_state = upper;
> break;
> case THERMAL_TREND_DROPPING:
> if (cur_state == instance->lower) {
> diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c
> index 5b7863a..f02e4d4 100644
> --- a/drivers/thermal/thermal_sys.c
> +++ b/drivers/thermal/thermal_sys.c
> @@ -1134,11 +1134,10 @@ int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
>
> cdev->ops->get_max_state(cdev, &max_state);
>
> - /* lower default 0, upper default max_state */
> + /* lower default 0 */
> lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
> - upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
>
> - if (lower > upper || upper > max_state)
> + if (lower > upper || (upper != THERMAL_NO_LIMIT && upper > max_state))
> return -EINVAL;
>
> dev =