Hi Amit,
On Thu, May 08, 2014 at 03:37:57PM +0100, Amit Daniel Kachhap wrote:
> This patch adds notification support for those clients of cpu_cooling
> APIs which may want to do something interesting after receiving these
> cpu_cooling events. The notifier structure passed is of both Set/Get type.
> The notfications events can be of type,
> 1. CPU_COOLING_SET_STATE_PRE
> 2. CPU_COOLING_SET_STATE_POST
> 3. CPU_COOLING_GET_CUR_STATE
> 4. CPU_COOLING_GET_MAX_STATE
>
> The advantages of these notfications is to differentiate between different
> P states in the cpufreq table and the cooling states. The clients of these
> events may group few P states into 1 cooling states. Also some more cooling
> states can be enabled when the maximum of P state is reached. Post notifications
> can be used for those cases.
>
> Signed-off-by: Amit Daniel Kachhap <amit.daniel@xxxxxxxxxxx>
> ---
> drivers/thermal/cpu_cooling.c | 99 +++++++++++++++++++++++++++++++++++++++-
> include/linux/cpu_cooling.h | 55 +++++++++++++++++++++++
> 2 files changed, 151 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
> index 21f44d4..e2aeb36 100644
> --- a/drivers/thermal/cpu_cooling.c
> +++ b/drivers/thermal/cpu_cooling.c
> @@ -50,6 +50,7 @@ struct cpufreq_cooling_device {
> unsigned int cpufreq_state;
> unsigned int cpufreq_val;
> struct cpumask allowed_cpus;
> + struct cpufreq_cooling_status request_status;
> struct list_head node;
> };
> static DEFINE_IDR(cpufreq_idr);
> @@ -59,6 +60,8 @@ static DEFINE_MUTEX(cooling_cpufreq_lock);
> #define NOTIFY_INVALID NULL
> static struct cpufreq_cooling_device *notify_device;
>
> +/* Notfier list to validates/updates the cpufreq cooling states */
> +static BLOCKING_NOTIFIER_HEAD(cpufreq_cooling_state_notifier_list);
> /* A list to hold all the cpufreq cooling devices registered */
> static LIST_HEAD(cpufreq_cooling_list);
>
> @@ -266,6 +269,21 @@ static unsigned int get_cpu_frequency(unsigned int cpu, unsigned long level)
> return freq;
> }
>
> +static int
> +cpufreq_cooling_notify_states(struct cpufreq_cooling_status *request,
> + enum cpu_cooling_state_ops op)
> +{
> + /* Invoke the notifiers which have registered for this state change */
> + if (op == CPU_COOLING_SET_STATE_PRE ||
> + op == CPU_COOLING_SET_STATE_POST ||
> + op == CPU_COOLING_GET_MAX_STATE ||
> + op == CPU_COOLING_GET_CUR_STATE) {
> + blocking_notifier_call_chain(
> + &cpufreq_cooling_state_notifier_list, op, request);
> + }
> + return 0;
> +}
> +
> /**
> * cpufreq_apply_cooling - function to apply frequency clipping.
> * @cpufreq_device: cpufreq_cooling_device pointer containing frequency
> @@ -285,9 +303,18 @@ static int cpufreq_apply_cooling(struct cpufreq_cooling_device *cpufreq_device,
> struct cpumask *mask = &cpufreq_device->allowed_cpus;
> unsigned int cpu = cpumask_any(mask);
>
> + cpufreq_device->request_status.cur_state =
> + cpufreq_device->cpufreq_state;
> + cpufreq_device->request_status.new_state = cooling_state;
> +
> + cpufreq_cooling_notify_states(&cpufreq_device->request_status,
> + CPU_COOLING_SET_STATE_PRE);
> +
> + cooling_state = cpufreq_device->request_status.new_state;
>
> /* Check if the old cooling action is same as new cooling action */
> - if (cpufreq_device->cpufreq_state == cooling_state)
> + if (cpufreq_device->cpufreq_state ==
> + cpufreq_device->request_status.new_state)
> return 0;
>
> clip_freq = get_cpu_frequency(cpu, cooling_state);
> @@ -304,7 +331,8 @@ static int cpufreq_apply_cooling(struct cpufreq_cooling_device *cpufreq_device,
> }
>
> notify_device = NOTIFY_INVALID;
> -
> + cpufreq_cooling_notify_states(&cpufreq_device->request_status,
> + CPU_COOLING_SET_STATE_POST);
> return 0;
> }
>
> @@ -383,6 +411,11 @@ static int cpufreq_get_max_state(struct thermal_cooling_device *cdev,
> if (count > 0)
> *state = count;
>
> + cpufreq_device->request_status.max_state = count;
> + cpufreq_cooling_notify_states(&cpufreq_device->request_status,
> + CPU_COOLING_GET_MAX_STATE);
> + *state = cpufreq_device->request_status.max_state;
> +
I think this should all be inside the "if (count > 0)". If not, then
remove it, as it is dead code now.
Cheers,
Javi
