@@ -21,39 +21,33 @@
struct int3406_thermal_data {
int upper_limit;
- int upper_limit_index;
int lower_limit;
- int lower_limit_index;
acpi_handle handle;
struct acpi_video_device_brightness *br;
struct backlight_device *raw_bd;
struct thermal_cooling_device *cooling_dev;
};
-static int int3406_thermal_to_raw(int level, struct int3406_thermal_data *d)
-{
- int max_level = d->br->levels[d->br->count - 1];
- int raw_max = d->raw_bd->props.max_brightness;
-
- return level * raw_max / max_level;
-}
-
-static int int3406_thermal_to_acpi(int level, struct int3406_thermal_data *d)
-{
- int raw_max = d->raw_bd->props.max_brightness;
- int max_level = d->br->levels[d->br->count - 1];
-
- return level * max_level / raw_max;
-}
+/*
+ * According to the ACPI spec,
+ * "Each brightness level is represented by a number between 0 and 100,
+ * and can be thought of as a percentage. For example, 50 can be 50%
+ * power consumption or 50% brightness, as defined by the OEM."
+ *
+ * As int3406 device uses this value to communicate with the native
+ * graphics driver, we make the assumption that it represents
+ * the percentage of brightness only
+ */
+#define ACPI_TO_RAW(v, d) (d->raw_bd->props.max_brightness * v / 100)
+#define RAW_TO_ACPI(v, d) (v * 100 / d->raw_bd->props.max_brightness)
static int
int3406_thermal_get_max_state(struct thermal_cooling_device *cooling_dev,
unsigned long *state)
{
struct int3406_thermal_data *d = cooling_dev->devdata;
- int index = d->lower_limit_index ? d->lower_limit_index : 2;
- *state = d->br->count - 1 - index;
+ *state = d->upper_limit - d->lower_limit;
return 0;
}
@@ -62,19 +56,15 @@ int3406_thermal_set_cur_state(struct thermal_cooling_device *cooling_dev,
unsigned long state)
{
struct int3406_thermal_data *d = cooling_dev->devdata;
- int level, raw_level;
+ int acpi_level, raw_level;
- if (state > d->br->count - 3)
+ if (state > d->upper_limit - d->lower_limit)
return -EINVAL;
- state = d->br->count - 1 - state;
- level = d->br->levels[state];
+ acpi_level = d->br->levels[d->upper_limit - state];
- if ((d->upper_limit && level > d->upper_limit) ||
- (d->lower_limit && level < d->lower_limit))
- return -EINVAL;
+ raw_level = ACPI_TO_RAW(acpi_level, d);
- raw_level = int3406_thermal_to_raw(level, d);
return backlight_device_set_brightness(d->raw_bd, raw_level);
}
@@ -83,27 +73,22 @@ int3406_thermal_get_cur_state(struct thermal_cooling_device *cooling_dev,
unsigned long *state)
{
struct int3406_thermal_data *d = cooling_dev->devdata;
- int raw_level, level, i;
- int *levels = d->br->levels;
+ int acpi_level;
+ int index;
- raw_level = d->raw_bd->props.brightness;
- level = int3406_thermal_to_acpi(raw_level, d);
+ acpi_level = RAW_TO_ACPI(d->raw_bd->props.brightness, d);
/*
- * There is no 1:1 mapping between the firmware interface level with the
- * raw interface level, we will have to find one that is close enough.
+ * There is no 1:1 mapping between the firmware interface level
+ * with the raw interface level, we will have to find one that is
+ * right above it.
*/
- for (i = 2; i < d->br->count; i++) {
- if (level < levels[i]) {
- if (i == 2)
- break;
- if ((level - levels[i - 1]) < (levels[i] - level))
- i--;
+ for (index = d->lower_limit; index < d->upper_limit; index++) {
+ if (acpi_level <= d->br->levels[index])
break;
- }
}
- *state = d->br->count - 1 - i;
+ *state = d->upper_limit - index;
return 0;
}
@@ -117,7 +102,7 @@ static int int3406_thermal_get_index(int *array, int nr, int value)
{
int i;
- for (i = 0; i < nr; i++) {
+ for (i = 2; i < nr; i++) {
if (array[i] == value)
break;
}
@@ -131,24 +116,18 @@ static void int3406_thermal_get_limit(struct int3406_thermal_data *d)
int index;
status = acpi_evaluate_integer(d->handle, "DDDL", NULL, &lower_limit);
- if (ACPI_SUCCESS(status)) {
- index = int3406_thermal_get_index(d->br->levels, d->br->count,
- lower_limit);
- if (index > 0) {
- d->lower_limit = (int)lower_limit;
- d->lower_limit_index = index;
- }
- }
+ if (ACPI_SUCCESS(status))
+ d->lower_limit = int3406_thermal_get_index(d->br->levels,
+ d->br->count, lower_limit);
status = acpi_evaluate_integer(d->handle, "DDPC", NULL, &upper_limit);
- if (ACPI_SUCCESS(status)) {
- index = int3406_thermal_get_index(d->br->levels, d->br->count,
- upper_limit);
- if (index > 0) {
- d->upper_limit = (int)upper_limit;
- d->upper_limit_index = index;
- }
- }
+ if (ACPI_SUCCESS(status))
+ d->upper_limit = int3406_thermal_get_index(d->br->levels,
+ d->br->count, upper_limit);
+
+ /* lower_limit and upper_limit should be always set */
+ d->lower_limit = d->lower_limit > 0 ? d->lower_limit : 2;
+ d->upper_limit = d->upper_limit > 0 ? d->upper_limit : d->br->count - 1;
}
static void int3406_notify(acpi_handle handle, u32 event, void *data)
there are three concepts represent backlight in int3406_thermal driver. 1. the raw brightness value from native graphics driver. 2. the percentage numbers from ACPI _BCL control method. 3. the consecutive numbers represent cooling states. int3406_thermal driver 1. uses value from DDDL/DDPC as the lower/upper limit, which is consistent with ACPI _BCL control methods. 2. reads current and maximum brightness from the native graphics driver. 3. expose them to thermal sysfs I/F This patch fixes the code that switches between the raw brightness value and the cooling state, which results in bogus value in thermal sysfs I/F. Signed-off-by: Zhang Rui <rui.zhang@intel.com> --- drivers/thermal/int340x_thermal/int3406_thermal.c | 95 +++++++++-------------- 1 file changed, 37 insertions(+), 58 deletions(-)