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Diffstat (limited to 'drivers/thermal/intel/int340x_thermal/int3406_thermal.c')
-rw-r--r--drivers/thermal/intel/int340x_thermal/int3406_thermal.c209
1 files changed, 209 insertions, 0 deletions
diff --git a/drivers/thermal/intel/int340x_thermal/int3406_thermal.c b/drivers/thermal/intel/int340x_thermal/int3406_thermal.c
new file mode 100644
index 000000000..f5e42fc2a
--- /dev/null
+++ b/drivers/thermal/intel/int340x_thermal/int3406_thermal.c
@@ -0,0 +1,209 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * INT3406 thermal driver for display participant device
+ *
+ * Copyright (C) 2016, Intel Corporation
+ * Authors: Aaron Lu <aaron.lu@intel.com>
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/acpi.h>
+#include <linux/backlight.h>
+#include <linux/thermal.h>
+#include <acpi/video.h>
+
+#define INT3406_BRIGHTNESS_LIMITS_CHANGED 0x80
+
+struct int3406_thermal_data {
+ int upper_limit;
+ int lower_limit;
+ acpi_handle handle;
+ struct acpi_video_device_brightness *br;
+ struct backlight_device *raw_bd;
+ struct thermal_cooling_device *cooling_dev;
+};
+
+/*
+ * 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;
+
+ *state = d->upper_limit - d->lower_limit;
+ return 0;
+}
+
+static int
+int3406_thermal_set_cur_state(struct thermal_cooling_device *cooling_dev,
+ unsigned long state)
+{
+ struct int3406_thermal_data *d = cooling_dev->devdata;
+ int acpi_level, raw_level;
+
+ if (state > d->upper_limit - d->lower_limit)
+ return -EINVAL;
+
+ acpi_level = d->br->levels[d->upper_limit - state];
+
+ raw_level = ACPI_TO_RAW(acpi_level, d);
+
+ return backlight_device_set_brightness(d->raw_bd, raw_level);
+}
+
+static int
+int3406_thermal_get_cur_state(struct thermal_cooling_device *cooling_dev,
+ unsigned long *state)
+{
+ struct int3406_thermal_data *d = cooling_dev->devdata;
+ int acpi_level;
+ int index;
+
+ 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
+ * right above it.
+ */
+ for (index = d->lower_limit; index < d->upper_limit; index++) {
+ if (acpi_level <= d->br->levels[index])
+ break;
+ }
+
+ *state = d->upper_limit - index;
+ return 0;
+}
+
+static const struct thermal_cooling_device_ops video_cooling_ops = {
+ .get_max_state = int3406_thermal_get_max_state,
+ .get_cur_state = int3406_thermal_get_cur_state,
+ .set_cur_state = int3406_thermal_set_cur_state,
+};
+
+static int int3406_thermal_get_index(int *array, int nr, int value)
+{
+ int i;
+
+ for (i = 2; i < nr; i++) {
+ if (array[i] == value)
+ break;
+ }
+ return i == nr ? -ENOENT : i;
+}
+
+static void int3406_thermal_get_limit(struct int3406_thermal_data *d)
+{
+ acpi_status status;
+ unsigned long long lower_limit, upper_limit;
+
+ status = acpi_evaluate_integer(d->handle, "DDDL", NULL, &lower_limit);
+ 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))
+ 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)
+{
+ if (event == INT3406_BRIGHTNESS_LIMITS_CHANGED)
+ int3406_thermal_get_limit(data);
+}
+
+static int int3406_thermal_probe(struct platform_device *pdev)
+{
+ struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
+ struct int3406_thermal_data *d;
+ struct backlight_device *bd;
+ int ret;
+
+ if (!ACPI_HANDLE(&pdev->dev))
+ return -ENODEV;
+
+ d = devm_kzalloc(&pdev->dev, sizeof(*d), GFP_KERNEL);
+ if (!d)
+ return -ENOMEM;
+ d->handle = ACPI_HANDLE(&pdev->dev);
+
+ bd = backlight_device_get_by_type(BACKLIGHT_RAW);
+ if (!bd)
+ return -ENODEV;
+ d->raw_bd = bd;
+
+ ret = acpi_video_get_levels(ACPI_COMPANION(&pdev->dev), &d->br, NULL);
+ if (ret)
+ return ret;
+
+ int3406_thermal_get_limit(d);
+
+ d->cooling_dev = thermal_cooling_device_register(acpi_device_bid(adev),
+ d, &video_cooling_ops);
+ if (IS_ERR(d->cooling_dev))
+ goto err;
+
+ ret = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
+ int3406_notify, d);
+ if (ret)
+ goto err_cdev;
+
+ platform_set_drvdata(pdev, d);
+
+ return 0;
+
+err_cdev:
+ thermal_cooling_device_unregister(d->cooling_dev);
+err:
+ kfree(d->br);
+ return -ENODEV;
+}
+
+static int int3406_thermal_remove(struct platform_device *pdev)
+{
+ struct int3406_thermal_data *d = platform_get_drvdata(pdev);
+
+ thermal_cooling_device_unregister(d->cooling_dev);
+ kfree(d->br);
+ return 0;
+}
+
+static const struct acpi_device_id int3406_thermal_match[] = {
+ {"INT3406", 0},
+ {}
+};
+
+MODULE_DEVICE_TABLE(acpi, int3406_thermal_match);
+
+static struct platform_driver int3406_thermal_driver = {
+ .probe = int3406_thermal_probe,
+ .remove = int3406_thermal_remove,
+ .driver = {
+ .name = "int3406 thermal",
+ .acpi_match_table = int3406_thermal_match,
+ },
+};
+
+module_platform_driver(int3406_thermal_driver);
+
+MODULE_DESCRIPTION("INT3406 Thermal driver");
+MODULE_LICENSE("GPL v2");