diff options
| author | Bernie Thompson <bernie@plugable.com> | 2010-09-06 03:35:31 +0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-09-06 03:50:21 +0400 |
| commit | 8ef8cc4fca4a92e77c0b5aa7a852a6c3d2fba844 (patch) | |
| tree | a3ef0a17f95280e2ec63212d5dffe3deb2dd6ac1 /drivers/staging/udlfb | |
| parent | 1572f91cffd7c0d64ab4e0cec71e1d2d1a3349e1 (diff) | |
| download | linux-8ef8cc4fca4a92e77c0b5aa7a852a6c3d2fba844.tar.xz | |
staging: udlfb: support for writing backup EDID to sysfs file
Support writing default/backup edid via /sys/class/graphics/fb?/edid
Writing a backup edid blob to the 'edid' file will cause udlfb to
attempt to re-read the edid from hardware.
If we still don't have a good edid, it will use the backup edid instead.
The intent is to 1) enable user-supplied edid
2) enable udev rules to backup the last known good edid
for a device, and then provide that edid as a backup for all future starts
Signed-off-by: Bernie Thompson <bernie@plugable.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/staging/udlfb')
| -rw-r--r-- | drivers/staging/udlfb/udlfb.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/drivers/staging/udlfb/udlfb.c b/drivers/staging/udlfb/udlfb.c index bcb4a1e9e713..b13869bbe09d 100644 --- a/drivers/staging/udlfb/udlfb.c +++ b/drivers/staging/udlfb/udlfb.c @@ -1306,6 +1306,29 @@ static ssize_t edid_show( return count; } +static ssize_t edid_store( + struct file *filp, + struct kobject *kobj, struct bin_attribute *a, + char *src, loff_t src_off, size_t src_size) { + struct device *fbdev = container_of(kobj, struct device, kobj); + struct fb_info *fb_info = dev_get_drvdata(fbdev); + struct dlfb_data *dev = fb_info->par; + + /* We only support write of entire EDID at once, no offset*/ + if ((src_size < MIN_EDID_SIZE) || + (src_size > MAX_EDID_SIZE) || + (src_off != 0)) + return 0; + + dlfb_setup_modes(dev, fb_info, src, src_size); + + if (dev->edid && (memcmp(src, dev->edid, src_size) == 0)) { + dl_info("sysfs written EDID is new default\n"); + dlfb_ops_set_par(fb_info); + return src_size; + } else + return 0; +} static ssize_t metrics_reset_store(struct device *fbdev, struct device_attribute *attr, @@ -1348,9 +1371,10 @@ static ssize_t use_defio_store(struct device *fbdev, static struct bin_attribute edid_attr = { .attr.name = "edid", - .attr.mode = 0444, - .size = 128, + .attr.mode = 0666, + .size = MAX_EDID_SIZE, .read = edid_show, + .write = edid_store }; static struct device_attribute fb_device_attrs[] = { |