ACPI: Add support for exposing BGRT data
ACPI 5.0 adds the BGRT, a table that contains a pointer to the firmware
boot splash and associated metadata. This simple driver exposes it via
/sys/firmware/acpi in order to allow bootsplash applications to draw their
splash around the firmware image and reduce the number of jarring graphical
transitions during boot.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/bgrt.c b/drivers/acpi/bgrt.c
new file mode 100644
index 0000000..8cf6c46
--- /dev/null
+++ b/drivers/acpi/bgrt.c
@@ -0,0 +1,175 @@
+/*
+ * Copyright 2012 Red Hat, Inc <mjg@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/sysfs.h>
+#include <acpi/acpi.h>
+#include <acpi/acpi_bus.h>
+
+static struct acpi_table_bgrt *bgrt_tab;
+static struct kobject *bgrt_kobj;
+
+struct bmp_header {
+ u16 id;
+ u32 size;
+} __attribute ((packed));
+
+static struct bmp_header bmp_header;
+
+static ssize_t show_version(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->version);
+}
+static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
+
+static ssize_t show_status(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->status);
+}
+static DEVICE_ATTR(status, S_IRUGO, show_status, NULL);
+
+static ssize_t show_type(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->image_type);
+}
+static DEVICE_ATTR(type, S_IRUGO, show_type, NULL);
+
+static ssize_t show_xoffset(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->image_offset_x);
+}
+static DEVICE_ATTR(xoffset, S_IRUGO, show_xoffset, NULL);
+
+static ssize_t show_yoffset(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->image_offset_y);
+}
+static DEVICE_ATTR(yoffset, S_IRUGO, show_yoffset, NULL);
+
+static ssize_t show_image(struct file *file, struct kobject *kobj,
+ struct bin_attribute *attr, char *buf, loff_t off, size_t count)
+{
+ int size = attr->size;
+ void __iomem *image = attr->private;
+
+ if (off >= size) {
+ count = 0;
+ } else {
+ if (off + count > size)
+ count = size - off;
+
+ memcpy_fromio(buf, image+off, count);
+ }
+
+ return count;
+}
+
+static struct bin_attribute image_attr = {
+ .attr = {
+ .name = "image",
+ .mode = S_IRUGO,
+ },
+ .read = show_image,
+};
+
+static struct attribute *bgrt_attributes[] = {
+ &dev_attr_version.attr,
+ &dev_attr_status.attr,
+ &dev_attr_type.attr,
+ &dev_attr_xoffset.attr,
+ &dev_attr_yoffset.attr,
+ NULL,
+};
+
+static struct attribute_group bgrt_attribute_group = {
+ .attrs = bgrt_attributes,
+};
+
+static int __init bgrt_init(void)
+{
+ acpi_status status;
+ int ret;
+ void __iomem *bgrt;
+
+ if (acpi_disabled)
+ return -ENODEV;
+
+ status = acpi_get_table("BGRT", 0,
+ (struct acpi_table_header **)&bgrt_tab);
+
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ sysfs_bin_attr_init(&image_attr);
+
+ bgrt = ioremap(bgrt_tab->image_address, sizeof(struct bmp_header));
+
+ if (!bgrt) {
+ ret = -EINVAL;
+ goto out_err;
+ }
+
+ memcpy_fromio(&bmp_header, bgrt, sizeof(bmp_header));
+ image_attr.size = bmp_header.size;
+ iounmap(bgrt);
+
+ image_attr.private = ioremap(bgrt_tab->image_address, image_attr.size);
+
+ if (!image_attr.private) {
+ ret = -EINVAL;
+ goto out_err;
+ }
+
+
+ bgrt_kobj = kobject_create_and_add("bgrt", acpi_kobj);
+ if (!bgrt_kobj) {
+ ret = -EINVAL;
+ goto out_iounmap;
+ }
+
+ ret = sysfs_create_group(bgrt_kobj, &bgrt_attribute_group);
+ if (ret)
+ goto out_kobject;
+
+ ret = sysfs_create_bin_file(bgrt_kobj, &image_attr);
+ if (ret)
+ goto out_group;
+
+ return 0;
+
+out_group:
+ sysfs_remove_group(bgrt_kobj, &bgrt_attribute_group);
+out_kobject:
+ kobject_put(bgrt_kobj);
+out_iounmap:
+ iounmap(image_attr.private);
+out_err:
+ return ret;
+}
+
+static void __exit bgrt_exit(void)
+{
+ iounmap(image_attr.private);
+ sysfs_remove_group(bgrt_kobj, &bgrt_attribute_group);
+ sysfs_remove_bin_file(bgrt_kobj, &image_attr);
+}
+
+module_init(bgrt_init);
+module_exit(bgrt_exit);
+
+MODULE_AUTHOR("Matthew Garrett");
+MODULE_DESCRIPTION("BGRT boot graphic support");
+MODULE_LICENSE("GPL");