linux-stable/drivers/gpu/drm/drm_sysfs.c
Ramalingam C 79643fddd6 drm/hdcp: optimizing the srm handling
As we are not using the sysfs infrastructure anymore, link to it is
removed. And global srm data and mutex to protect it are removed,
with required handling at revocation check function.

v2:
  srm_data is dropped and few more comments are addressed.
v3:
  ptr passing around is fixed with functional testing.
v4:
  fix htmldoc [lkp]

Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Suggested-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20200212102942.26568-2-ramalingam.c@intel.com
2020-03-04 06:33:00 +05:30

450 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* drm_sysfs.c - Modifications to drm_sysfs_class.c to support
* extra sysfs attribute from DRM. Normal drm_sysfs_class
* does not allow adding attributes.
*
* Copyright (c) 2004 Jon Smirl <jonsmirl@gmail.com>
* Copyright (c) 2003-2004 Greg Kroah-Hartman <greg@kroah.com>
* Copyright (c) 2003-2004 IBM Corp.
*/
#include <linux/device.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/gfp.h>
#include <linux/i2c.h>
#include <linux/kdev_t.h>
#include <linux/slab.h>
#include <drm/drm_connector.h>
#include <drm/drm_device.h>
#include <drm/drm_file.h>
#include <drm/drm_modes.h>
#include <drm/drm_print.h>
#include <drm/drm_property.h>
#include <drm/drm_sysfs.h>
#include "drm_internal.h"
#include "drm_crtc_internal.h"
#define to_drm_minor(d) dev_get_drvdata(d)
#define to_drm_connector(d) dev_get_drvdata(d)
/**
* DOC: overview
*
* DRM provides very little additional support to drivers for sysfs
* interactions, beyond just all the standard stuff. Drivers who want to expose
* additional sysfs properties and property groups can attach them at either
* &drm_device.dev or &drm_connector.kdev.
*
* Registration is automatically handled when calling drm_dev_register(), or
* drm_connector_register() in case of hot-plugged connectors. Unregistration is
* also automatically handled by drm_dev_unregister() and
* drm_connector_unregister().
*/
static struct device_type drm_sysfs_device_minor = {
.name = "drm_minor"
};
struct class *drm_class;
static char *drm_devnode(struct device *dev, umode_t *mode)
{
return kasprintf(GFP_KERNEL, "dri/%s", dev_name(dev));
}
static CLASS_ATTR_STRING(version, S_IRUGO, "drm 1.1.0 20060810");
/**
* drm_sysfs_init - initialize sysfs helpers
*
* This is used to create the DRM class, which is the implicit parent of any
* other top-level DRM sysfs objects.
*
* You must call drm_sysfs_destroy() to release the allocated resources.
*
* Return: 0 on success, negative error code on failure.
*/
int drm_sysfs_init(void)
{
int err;
drm_class = class_create(THIS_MODULE, "drm");
if (IS_ERR(drm_class))
return PTR_ERR(drm_class);
err = class_create_file(drm_class, &class_attr_version.attr);
if (err) {
class_destroy(drm_class);
drm_class = NULL;
return err;
}
drm_class->devnode = drm_devnode;
return 0;
}
/**
* drm_sysfs_destroy - destroys DRM class
*
* Destroy the DRM device class.
*/
void drm_sysfs_destroy(void)
{
if (IS_ERR_OR_NULL(drm_class))
return;
class_remove_file(drm_class, &class_attr_version.attr);
class_destroy(drm_class);
drm_class = NULL;
}
/*
* Connector properties
*/
static ssize_t status_store(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct drm_connector *connector = to_drm_connector(device);
struct drm_device *dev = connector->dev;
enum drm_connector_force old_force;
int ret;
ret = mutex_lock_interruptible(&dev->mode_config.mutex);
if (ret)
return ret;
old_force = connector->force;
if (sysfs_streq(buf, "detect"))
connector->force = 0;
else if (sysfs_streq(buf, "on"))
connector->force = DRM_FORCE_ON;
else if (sysfs_streq(buf, "on-digital"))
connector->force = DRM_FORCE_ON_DIGITAL;
else if (sysfs_streq(buf, "off"))
connector->force = DRM_FORCE_OFF;
else
ret = -EINVAL;
if (old_force != connector->force || !connector->force) {
DRM_DEBUG_KMS("[CONNECTOR:%d:%s] force updated from %d to %d or reprobing\n",
connector->base.id,
connector->name,
old_force, connector->force);
connector->funcs->fill_modes(connector,
dev->mode_config.max_width,
dev->mode_config.max_height);
}
mutex_unlock(&dev->mode_config.mutex);
return ret ? ret : count;
}
static ssize_t status_show(struct device *device,
struct device_attribute *attr,
char *buf)
{
struct drm_connector *connector = to_drm_connector(device);
enum drm_connector_status status;
status = READ_ONCE(connector->status);
return snprintf(buf, PAGE_SIZE, "%s\n",
drm_get_connector_status_name(status));
}
static ssize_t dpms_show(struct device *device,
struct device_attribute *attr,
char *buf)
{
struct drm_connector *connector = to_drm_connector(device);
int dpms;
dpms = READ_ONCE(connector->dpms);
return snprintf(buf, PAGE_SIZE, "%s\n",
drm_get_dpms_name(dpms));
}
static ssize_t enabled_show(struct device *device,
struct device_attribute *attr,
char *buf)
{
struct drm_connector *connector = to_drm_connector(device);
bool enabled;
enabled = READ_ONCE(connector->encoder);
return snprintf(buf, PAGE_SIZE, enabled ? "enabled\n" : "disabled\n");
}
static ssize_t edid_show(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr, char *buf, loff_t off,
size_t count)
{
struct device *connector_dev = kobj_to_dev(kobj);
struct drm_connector *connector = to_drm_connector(connector_dev);
unsigned char *edid;
size_t size;
ssize_t ret = 0;
mutex_lock(&connector->dev->mode_config.mutex);
if (!connector->edid_blob_ptr)
goto unlock;
edid = connector->edid_blob_ptr->data;
size = connector->edid_blob_ptr->length;
if (!edid)
goto unlock;
if (off >= size)
goto unlock;
if (off + count > size)
count = size - off;
memcpy(buf, edid + off, count);
ret = count;
unlock:
mutex_unlock(&connector->dev->mode_config.mutex);
return ret;
}
static ssize_t modes_show(struct device *device,
struct device_attribute *attr,
char *buf)
{
struct drm_connector *connector = to_drm_connector(device);
struct drm_display_mode *mode;
int written = 0;
mutex_lock(&connector->dev->mode_config.mutex);
list_for_each_entry(mode, &connector->modes, head) {
written += snprintf(buf + written, PAGE_SIZE - written, "%s\n",
mode->name);
}
mutex_unlock(&connector->dev->mode_config.mutex);
return written;
}
static DEVICE_ATTR_RW(status);
static DEVICE_ATTR_RO(enabled);
static DEVICE_ATTR_RO(dpms);
static DEVICE_ATTR_RO(modes);
static struct attribute *connector_dev_attrs[] = {
&dev_attr_status.attr,
&dev_attr_enabled.attr,
&dev_attr_dpms.attr,
&dev_attr_modes.attr,
NULL
};
static struct bin_attribute edid_attr = {
.attr.name = "edid",
.attr.mode = 0444,
.size = 0,
.read = edid_show,
};
static struct bin_attribute *connector_bin_attrs[] = {
&edid_attr,
NULL
};
static const struct attribute_group connector_dev_group = {
.attrs = connector_dev_attrs,
.bin_attrs = connector_bin_attrs,
};
static const struct attribute_group *connector_dev_groups[] = {
&connector_dev_group,
NULL
};
int drm_sysfs_connector_add(struct drm_connector *connector)
{
struct drm_device *dev = connector->dev;
if (connector->kdev)
return 0;
connector->kdev =
device_create_with_groups(drm_class, dev->primary->kdev, 0,
connector, connector_dev_groups,
"card%d-%s", dev->primary->index,
connector->name);
DRM_DEBUG("adding \"%s\" to sysfs\n",
connector->name);
if (IS_ERR(connector->kdev)) {
DRM_ERROR("failed to register connector device: %ld\n", PTR_ERR(connector->kdev));
return PTR_ERR(connector->kdev);
}
/* Let userspace know we have a new connector */
drm_sysfs_hotplug_event(dev);
if (connector->ddc)
return sysfs_create_link(&connector->kdev->kobj,
&connector->ddc->dev.kobj, "ddc");
return 0;
}
void drm_sysfs_connector_remove(struct drm_connector *connector)
{
if (!connector->kdev)
return;
if (connector->ddc)
sysfs_remove_link(&connector->kdev->kobj, "ddc");
DRM_DEBUG("removing \"%s\" from sysfs\n",
connector->name);
device_unregister(connector->kdev);
connector->kdev = NULL;
}
void drm_sysfs_lease_event(struct drm_device *dev)
{
char *event_string = "LEASE=1";
char *envp[] = { event_string, NULL };
DRM_DEBUG("generating lease event\n");
kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
}
/**
* drm_sysfs_hotplug_event - generate a DRM uevent
* @dev: DRM device
*
* Send a uevent for the DRM device specified by @dev. Currently we only
* set HOTPLUG=1 in the uevent environment, but this could be expanded to
* deal with other types of events.
*
* Any new uapi should be using the drm_sysfs_connector_status_event()
* for uevents on connector status change.
*/
void drm_sysfs_hotplug_event(struct drm_device *dev)
{
char *event_string = "HOTPLUG=1";
char *envp[] = { event_string, NULL };
DRM_DEBUG("generating hotplug event\n");
kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
}
EXPORT_SYMBOL(drm_sysfs_hotplug_event);
/**
* drm_sysfs_connector_status_event - generate a DRM uevent for connector
* property status change
* @connector: connector on which property status changed
* @property: connector property whose status changed.
*
* Send a uevent for the DRM device specified by @dev. Currently we
* set HOTPLUG=1 and connector id along with the attached property id
* related to the status change.
*/
void drm_sysfs_connector_status_event(struct drm_connector *connector,
struct drm_property *property)
{
struct drm_device *dev = connector->dev;
char hotplug_str[] = "HOTPLUG=1", conn_id[21], prop_id[21];
char *envp[4] = { hotplug_str, conn_id, prop_id, NULL };
WARN_ON(!drm_mode_obj_find_prop_id(&connector->base,
property->base.id));
snprintf(conn_id, ARRAY_SIZE(conn_id),
"CONNECTOR=%u", connector->base.id);
snprintf(prop_id, ARRAY_SIZE(prop_id),
"PROPERTY=%u", property->base.id);
DRM_DEBUG("generating connector status event\n");
kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
}
EXPORT_SYMBOL(drm_sysfs_connector_status_event);
static void drm_sysfs_release(struct device *dev)
{
kfree(dev);
}
struct device *drm_sysfs_minor_alloc(struct drm_minor *minor)
{
const char *minor_str;
struct device *kdev;
int r;
if (minor->type == DRM_MINOR_RENDER)
minor_str = "renderD%d";
else
minor_str = "card%d";
kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
if (!kdev)
return ERR_PTR(-ENOMEM);
device_initialize(kdev);
kdev->devt = MKDEV(DRM_MAJOR, minor->index);
kdev->class = drm_class;
kdev->type = &drm_sysfs_device_minor;
kdev->parent = minor->dev->dev;
kdev->release = drm_sysfs_release;
dev_set_drvdata(kdev, minor);
r = dev_set_name(kdev, minor_str, minor->index);
if (r < 0)
goto err_free;
return kdev;
err_free:
put_device(kdev);
return ERR_PTR(r);
}
/**
* drm_class_device_register - register new device with the DRM sysfs class
* @dev: device to register
*
* Registers a new &struct device within the DRM sysfs class. Essentially only
* used by ttm to have a place for its global settings. Drivers should never use
* this.
*/
int drm_class_device_register(struct device *dev)
{
if (!drm_class || IS_ERR(drm_class))
return -ENOENT;
dev->class = drm_class;
return device_register(dev);
}
EXPORT_SYMBOL_GPL(drm_class_device_register);
/**
* drm_class_device_unregister - unregister device with the DRM sysfs class
* @dev: device to unregister
*
* Unregisters a &struct device from the DRM sysfs class. Essentially only used
* by ttm to have a place for its global settings. Drivers should never use
* this.
*/
void drm_class_device_unregister(struct device *dev)
{
return device_unregister(dev);
}
EXPORT_SYMBOL_GPL(drm_class_device_unregister);