platform/x86: wmi-bmof: Make use of .bin_size() callback

Until now the wmi-bmof driver had to allocate the binary sysfs
attribute dynamically since its size depends on the bmof buffer
returned by the firmware.

Use the new .bin_size() callback to avoid having to do this memory
allocation.

Tested on a Asus Prime B650-Plus.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20241206215650.2977-1-W_Armin@gmx.de
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

diff --git a/drivers/platform/x86/wmi-bmof.c b/drivers/platform/x86/wmi-bmof.c
index df6f0ae6e6c7904f97c125297a21166f56d0b1f0..3e33da36da8ada3648b58b2579181fd2cd4bfff3 100644 (file)
--- a/drivers/platform/x86/wmi-bmof.c
+++ b/drivers/platform/x86/wmi-bmof.c
@@ -20,66 +20,66 @@
 
 #define WMI_BMOF_GUID "05901221-D566-11D1-B2F0-00A0C9062910"
 
-struct bmof_priv {
-       union acpi_object *bmofdata;
-       struct bin_attribute bmof_bin_attr;
-};
-
-static ssize_t read_bmof(struct file *filp, struct kobject *kobj, struct bin_attribute *attr,
+static ssize_t bmof_read(struct file *filp, struct kobject *kobj, const struct bin_attribute *attr,
                         char *buf, loff_t off, size_t count)
 {
-       struct bmof_priv *priv = container_of(attr, struct bmof_priv, bmof_bin_attr);
+       struct device *dev = kobj_to_dev(kobj);
+       union acpi_object *obj = dev_get_drvdata(dev);
 
-       return memory_read_from_buffer(buf, count, &off, priv->bmofdata->buffer.pointer,
-                                      priv->bmofdata->buffer.length);
+       return memory_read_from_buffer(buf, count, &off, obj->buffer.pointer, obj->buffer.length);
 }
 
-static int wmi_bmof_probe(struct wmi_device *wdev, const void *context)
+static const BIN_ATTR_ADMIN_RO(bmof, 0);
+
+static const struct bin_attribute * const bmof_attrs[] = {
+       &bin_attr_bmof,
+       NULL
+};
+
+static size_t bmof_bin_size(struct kobject *kobj, const struct bin_attribute *attr, int n)
 {
-       struct bmof_priv *priv;
-       int ret;
+       struct device *dev = kobj_to_dev(kobj);
+       union acpi_object *obj = dev_get_drvdata(dev);
+
+       return obj->buffer.length;
+}
 
-       priv = devm_kzalloc(&wdev->dev, sizeof(struct bmof_priv), GFP_KERNEL);
-       if (!priv)
-               return -ENOMEM;
+static const struct attribute_group bmof_group = {
+       .bin_size = bmof_bin_size,
+       .bin_attrs_new = bmof_attrs,
+};
+
+static const struct attribute_group *bmof_groups[] = {
+       &bmof_group,
+       NULL
+};
 
-       dev_set_drvdata(&wdev->dev, priv);
+static int wmi_bmof_probe(struct wmi_device *wdev, const void *context)
+{
+       union acpi_object *obj;
 
-       priv->bmofdata = wmidev_block_query(wdev, 0);
-       if (!priv->bmofdata) {
+       obj = wmidev_block_query(wdev, 0);
+       if (!obj) {
                dev_err(&wdev->dev, "failed to read Binary MOF\n");
                return -EIO;
        }
 
-       if (priv->bmofdata->type != ACPI_TYPE_BUFFER) {
+       if (obj->type != ACPI_TYPE_BUFFER) {
                dev_err(&wdev->dev, "Binary MOF is not a buffer\n");
-               ret = -EIO;
-               goto err_free;
+               kfree(obj);
+               return -EIO;
        }
 
-       sysfs_bin_attr_init(&priv->bmof_bin_attr);
-       priv->bmof_bin_attr.attr.name = "bmof";
-       priv->bmof_bin_attr.attr.mode = 0400;
-       priv->bmof_bin_attr.read = read_bmof;
-       priv->bmof_bin_attr.size = priv->bmofdata->buffer.length;
-
-       ret = device_create_bin_file(&wdev->dev, &priv->bmof_bin_attr);
-       if (ret)
-               goto err_free;
+       dev_set_drvdata(&wdev->dev, obj);
 
        return 0;
-
- err_free:
-       kfree(priv->bmofdata);
-       return ret;
 }
 
 static void wmi_bmof_remove(struct wmi_device *wdev)
 {
-       struct bmof_priv *priv = dev_get_drvdata(&wdev->dev);
+       union acpi_object *obj = dev_get_drvdata(&wdev->dev);
 
-       device_remove_bin_file(&wdev->dev, &priv->bmof_bin_attr);
-       kfree(priv->bmofdata);
+       kfree(obj);
 }
 
 static const struct wmi_device_id wmi_bmof_id_table[] = {
@@ -90,6 +90,7 @@ static const struct wmi_device_id wmi_bmof_id_table[] = {
 static struct wmi_driver wmi_bmof_driver = {
        .driver = {
                .name = "wmi-bmof",
+               .dev_groups = bmof_groups,
        },
        .probe = wmi_bmof_probe,
        .remove = wmi_bmof_remove,