drivers/platform/x86/intel/int3472/common.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Author: Dan Scally <djrscally@gmail.com> */
   3
   4 #include <linux/acpi.h>
   5 #include <linux/slab.h>
   6
   7 #include "common.h"
   8
   9 union acpi_object *skl_int3472_get_acpi_buffer(struct acpi_device *adev, char *id)
  10 {
  11         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  12         acpi_handle handle = adev->handle;
  13         union acpi_object *obj;
  14         acpi_status status;
  15
  16         status = acpi_evaluate_object(handle, id, NULL, &buffer);
  17         if (ACPI_FAILURE(status))
  18                 return ERR_PTR(-ENODEV);
  19
  20         obj = buffer.pointer;
  21         if (!obj)
  22                 return ERR_PTR(-ENODEV);
  23
  24         if (obj->type != ACPI_TYPE_BUFFER) {
  25                 acpi_handle_err(handle, "%s object is not an ACPI buffer\n", id);
  26                 kfree(obj);
  27                 return ERR_PTR(-EINVAL);
  28         }
  29
  30         return obj;
  31 }
  32 EXPORT_SYMBOL_GPL(skl_int3472_get_acpi_buffer);
  33
  34 int skl_int3472_fill_cldb(struct acpi_device *adev, struct int3472_cldb *cldb)
  35 {
  36         union acpi_object *obj;
  37         int ret;
  38
  39         obj = skl_int3472_get_acpi_buffer(adev, "CLDB");
  40         if (IS_ERR(obj))
  41                 return PTR_ERR(obj);
  42
  43         if (obj->buffer.length > sizeof(*cldb)) {
  44                 acpi_handle_err(adev->handle, "The CLDB buffer is too large\n");
  45                 ret = -EINVAL;
  46                 goto out_free_obj;
  47         }
  48
  49         memcpy(cldb, obj->buffer.pointer, obj->buffer.length);
  50         ret = 0;
  51
  52 out_free_obj:
  53         kfree(obj);
  54         return ret;
  55 }
  56 EXPORT_SYMBOL_GPL(skl_int3472_fill_cldb);
  57
  58 /* sensor_adev_ret may be NULL, name_ret must not be NULL */
  59 int skl_int3472_get_sensor_adev_and_name(struct device *dev,
  60                                          struct acpi_device **sensor_adev_ret,
  61                                          const char **name_ret)
  62 {
  63         struct acpi_device *adev = ACPI_COMPANION(dev);
  64         struct acpi_device *sensor;
  65         int ret = 0;
  66
  67         sensor = acpi_dev_get_next_consumer_dev(adev, NULL);
  68         if (!sensor) {
  69                 dev_err(dev, "INT3472 seems to have no dependents.\n");
  70                 return -ENODEV;
  71         }
  72
  73         *name_ret = devm_kasprintf(dev, GFP_KERNEL, I2C_DEV_NAME_FORMAT,
  74                                    acpi_dev_name(sensor));
  75         if (!*name_ret)
  76                 ret = -ENOMEM;
  77
  78         if (ret == 0 && sensor_adev_ret)
  79                 *sensor_adev_ret = sensor;
  80         else
  81                 acpi_dev_put(sensor);
  82
  83         return ret;
  84 }
  85 EXPORT_SYMBOL_GPL(skl_int3472_get_sensor_adev_and_name);
  86
  87 MODULE_DESCRIPTION("Intel SkyLake INT3472 ACPI Device Driver library");
  88 MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>");
  89 MODULE_LICENSE("GPL");