mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
![Daniel Vetter](/assets/img/avatar_default.png)
They're only used internally within the dp helpers. Also nuke the kerneldoc (we only document the driver interface in the drm shared functions). And move the header file from the public include/ directory to the source files into drm_crtc_helper_internal.h, similar to how we already have drm_crtc_internal.h. While at it also move drm_fb_helper_modinit since that belongs in there, too. I noticed this all since I spotted kerneldoc which wasn't pulled into the rst templates. v2: Update Copyright date. Cc: Sean Paul <seanpaul@chromium.org> Cc: Rafael Antognolli <rafael.antognolli@intel.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1471034937-651-16-git-send-email-daniel.vetter@ffwll.ch
366 lines
8.9 KiB
C
366 lines
8.9 KiB
C
/*
|
|
* Copyright © 2015 Intel Corporation
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a
|
|
* copy of this software and associated documentation files (the "Software"),
|
|
* to deal in the Software without restriction, including without limitation
|
|
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
|
|
* and/or sell copies of the Software, and to permit persons to whom the
|
|
* Software is furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice (including the next
|
|
* paragraph) shall be included in all copies or substantial portions of the
|
|
* Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
|
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
|
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
|
|
* IN THE SOFTWARE.
|
|
*
|
|
* Authors:
|
|
* Rafael Antognolli <rafael.antognolli@intel.com>
|
|
*
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/uaccess.h>
|
|
#include <drm/drm_dp_helper.h>
|
|
#include <drm/drm_crtc.h>
|
|
#include <drm/drmP.h>
|
|
|
|
#include "drm_crtc_helper_internal.h"
|
|
|
|
struct drm_dp_aux_dev {
|
|
unsigned index;
|
|
struct drm_dp_aux *aux;
|
|
struct device *dev;
|
|
struct kref refcount;
|
|
atomic_t usecount;
|
|
};
|
|
|
|
#define DRM_AUX_MINORS 256
|
|
#define AUX_MAX_OFFSET (1 << 20)
|
|
static DEFINE_IDR(aux_idr);
|
|
static DEFINE_MUTEX(aux_idr_mutex);
|
|
static struct class *drm_dp_aux_dev_class;
|
|
static int drm_dev_major = -1;
|
|
|
|
static struct drm_dp_aux_dev *drm_dp_aux_dev_get_by_minor(unsigned index)
|
|
{
|
|
struct drm_dp_aux_dev *aux_dev = NULL;
|
|
|
|
mutex_lock(&aux_idr_mutex);
|
|
aux_dev = idr_find(&aux_idr, index);
|
|
if (!kref_get_unless_zero(&aux_dev->refcount))
|
|
aux_dev = NULL;
|
|
mutex_unlock(&aux_idr_mutex);
|
|
|
|
return aux_dev;
|
|
}
|
|
|
|
static struct drm_dp_aux_dev *alloc_drm_dp_aux_dev(struct drm_dp_aux *aux)
|
|
{
|
|
struct drm_dp_aux_dev *aux_dev;
|
|
int index;
|
|
|
|
aux_dev = kzalloc(sizeof(*aux_dev), GFP_KERNEL);
|
|
if (!aux_dev)
|
|
return ERR_PTR(-ENOMEM);
|
|
aux_dev->aux = aux;
|
|
atomic_set(&aux_dev->usecount, 1);
|
|
kref_init(&aux_dev->refcount);
|
|
|
|
mutex_lock(&aux_idr_mutex);
|
|
index = idr_alloc_cyclic(&aux_idr, aux_dev, 0, DRM_AUX_MINORS,
|
|
GFP_KERNEL);
|
|
mutex_unlock(&aux_idr_mutex);
|
|
if (index < 0) {
|
|
kfree(aux_dev);
|
|
return ERR_PTR(index);
|
|
}
|
|
aux_dev->index = index;
|
|
|
|
return aux_dev;
|
|
}
|
|
|
|
static void release_drm_dp_aux_dev(struct kref *ref)
|
|
{
|
|
struct drm_dp_aux_dev *aux_dev =
|
|
container_of(ref, struct drm_dp_aux_dev, refcount);
|
|
|
|
kfree(aux_dev);
|
|
}
|
|
|
|
static ssize_t name_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
ssize_t res;
|
|
struct drm_dp_aux_dev *aux_dev =
|
|
drm_dp_aux_dev_get_by_minor(MINOR(dev->devt));
|
|
|
|
if (!aux_dev)
|
|
return -ENODEV;
|
|
|
|
res = sprintf(buf, "%s\n", aux_dev->aux->name);
|
|
kref_put(&aux_dev->refcount, release_drm_dp_aux_dev);
|
|
|
|
return res;
|
|
}
|
|
static DEVICE_ATTR_RO(name);
|
|
|
|
static struct attribute *drm_dp_aux_attrs[] = {
|
|
&dev_attr_name.attr,
|
|
NULL,
|
|
};
|
|
ATTRIBUTE_GROUPS(drm_dp_aux);
|
|
|
|
static int auxdev_open(struct inode *inode, struct file *file)
|
|
{
|
|
unsigned int minor = iminor(inode);
|
|
struct drm_dp_aux_dev *aux_dev;
|
|
|
|
aux_dev = drm_dp_aux_dev_get_by_minor(minor);
|
|
if (!aux_dev)
|
|
return -ENODEV;
|
|
|
|
file->private_data = aux_dev;
|
|
return 0;
|
|
}
|
|
|
|
static loff_t auxdev_llseek(struct file *file, loff_t offset, int whence)
|
|
{
|
|
return fixed_size_llseek(file, offset, whence, AUX_MAX_OFFSET);
|
|
}
|
|
|
|
static ssize_t auxdev_read(struct file *file, char __user *buf, size_t count,
|
|
loff_t *offset)
|
|
{
|
|
size_t bytes_pending, num_bytes_processed = 0;
|
|
struct drm_dp_aux_dev *aux_dev = file->private_data;
|
|
ssize_t res = 0;
|
|
|
|
if (!atomic_inc_not_zero(&aux_dev->usecount))
|
|
return -ENODEV;
|
|
|
|
bytes_pending = min((loff_t)count, AUX_MAX_OFFSET - (*offset));
|
|
|
|
if (!access_ok(VERIFY_WRITE, buf, bytes_pending)) {
|
|
res = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
while (bytes_pending > 0) {
|
|
uint8_t localbuf[DP_AUX_MAX_PAYLOAD_BYTES];
|
|
ssize_t todo = min_t(size_t, bytes_pending, sizeof(localbuf));
|
|
|
|
if (signal_pending(current)) {
|
|
res = num_bytes_processed ?
|
|
num_bytes_processed : -ERESTARTSYS;
|
|
goto out;
|
|
}
|
|
|
|
res = drm_dp_dpcd_read(aux_dev->aux, *offset, localbuf, todo);
|
|
if (res <= 0) {
|
|
res = num_bytes_processed ? num_bytes_processed : res;
|
|
goto out;
|
|
}
|
|
if (__copy_to_user(buf + num_bytes_processed, localbuf, res)) {
|
|
res = num_bytes_processed ?
|
|
num_bytes_processed : -EFAULT;
|
|
goto out;
|
|
}
|
|
bytes_pending -= res;
|
|
*offset += res;
|
|
num_bytes_processed += res;
|
|
res = num_bytes_processed;
|
|
}
|
|
|
|
out:
|
|
atomic_dec(&aux_dev->usecount);
|
|
wake_up_atomic_t(&aux_dev->usecount);
|
|
return res;
|
|
}
|
|
|
|
static ssize_t auxdev_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *offset)
|
|
{
|
|
size_t bytes_pending, num_bytes_processed = 0;
|
|
struct drm_dp_aux_dev *aux_dev = file->private_data;
|
|
ssize_t res = 0;
|
|
|
|
if (!atomic_inc_not_zero(&aux_dev->usecount))
|
|
return -ENODEV;
|
|
|
|
bytes_pending = min((loff_t)count, AUX_MAX_OFFSET - *offset);
|
|
|
|
if (!access_ok(VERIFY_READ, buf, bytes_pending)) {
|
|
res = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
while (bytes_pending > 0) {
|
|
uint8_t localbuf[DP_AUX_MAX_PAYLOAD_BYTES];
|
|
ssize_t todo = min_t(size_t, bytes_pending, sizeof(localbuf));
|
|
|
|
if (signal_pending(current)) {
|
|
res = num_bytes_processed ?
|
|
num_bytes_processed : -ERESTARTSYS;
|
|
goto out;
|
|
}
|
|
|
|
if (__copy_from_user(localbuf,
|
|
buf + num_bytes_processed, todo)) {
|
|
res = num_bytes_processed ?
|
|
num_bytes_processed : -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
res = drm_dp_dpcd_write(aux_dev->aux, *offset, localbuf, todo);
|
|
if (res <= 0) {
|
|
res = num_bytes_processed ? num_bytes_processed : res;
|
|
goto out;
|
|
}
|
|
bytes_pending -= res;
|
|
*offset += res;
|
|
num_bytes_processed += res;
|
|
res = num_bytes_processed;
|
|
}
|
|
|
|
out:
|
|
atomic_dec(&aux_dev->usecount);
|
|
wake_up_atomic_t(&aux_dev->usecount);
|
|
return res;
|
|
}
|
|
|
|
static int auxdev_release(struct inode *inode, struct file *file)
|
|
{
|
|
struct drm_dp_aux_dev *aux_dev = file->private_data;
|
|
|
|
kref_put(&aux_dev->refcount, release_drm_dp_aux_dev);
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations auxdev_fops = {
|
|
.owner = THIS_MODULE,
|
|
.llseek = auxdev_llseek,
|
|
.read = auxdev_read,
|
|
.write = auxdev_write,
|
|
.open = auxdev_open,
|
|
.release = auxdev_release,
|
|
};
|
|
|
|
#define to_auxdev(d) container_of(d, struct drm_dp_aux_dev, aux)
|
|
|
|
static struct drm_dp_aux_dev *drm_dp_aux_dev_get_by_aux(struct drm_dp_aux *aux)
|
|
{
|
|
struct drm_dp_aux_dev *iter, *aux_dev = NULL;
|
|
int id;
|
|
|
|
/* don't increase kref count here because this function should only be
|
|
* used by drm_dp_aux_unregister_devnode. Thus, it will always have at
|
|
* least one reference - the one that drm_dp_aux_register_devnode
|
|
* created
|
|
*/
|
|
mutex_lock(&aux_idr_mutex);
|
|
idr_for_each_entry(&aux_idr, iter, id) {
|
|
if (iter->aux == aux) {
|
|
aux_dev = iter;
|
|
break;
|
|
}
|
|
}
|
|
mutex_unlock(&aux_idr_mutex);
|
|
return aux_dev;
|
|
}
|
|
|
|
static int auxdev_wait_atomic_t(atomic_t *p)
|
|
{
|
|
schedule();
|
|
return 0;
|
|
}
|
|
|
|
void drm_dp_aux_unregister_devnode(struct drm_dp_aux *aux)
|
|
{
|
|
struct drm_dp_aux_dev *aux_dev;
|
|
unsigned int minor;
|
|
|
|
aux_dev = drm_dp_aux_dev_get_by_aux(aux);
|
|
if (!aux_dev) /* attach must have failed */
|
|
return;
|
|
|
|
mutex_lock(&aux_idr_mutex);
|
|
idr_remove(&aux_idr, aux_dev->index);
|
|
mutex_unlock(&aux_idr_mutex);
|
|
|
|
atomic_dec(&aux_dev->usecount);
|
|
wait_on_atomic_t(&aux_dev->usecount, auxdev_wait_atomic_t,
|
|
TASK_UNINTERRUPTIBLE);
|
|
|
|
minor = aux_dev->index;
|
|
if (aux_dev->dev)
|
|
device_destroy(drm_dp_aux_dev_class,
|
|
MKDEV(drm_dev_major, minor));
|
|
|
|
DRM_DEBUG("drm_dp_aux_dev: aux [%s] unregistering\n", aux->name);
|
|
kref_put(&aux_dev->refcount, release_drm_dp_aux_dev);
|
|
}
|
|
|
|
int drm_dp_aux_register_devnode(struct drm_dp_aux *aux)
|
|
{
|
|
struct drm_dp_aux_dev *aux_dev;
|
|
int res;
|
|
|
|
aux_dev = alloc_drm_dp_aux_dev(aux);
|
|
if (IS_ERR(aux_dev))
|
|
return PTR_ERR(aux_dev);
|
|
|
|
aux_dev->dev = device_create(drm_dp_aux_dev_class, aux->dev,
|
|
MKDEV(drm_dev_major, aux_dev->index), NULL,
|
|
"drm_dp_aux%d", aux_dev->index);
|
|
if (IS_ERR(aux_dev->dev)) {
|
|
res = PTR_ERR(aux_dev->dev);
|
|
aux_dev->dev = NULL;
|
|
goto error;
|
|
}
|
|
|
|
DRM_DEBUG("drm_dp_aux_dev: aux [%s] registered as minor %d\n",
|
|
aux->name, aux_dev->index);
|
|
return 0;
|
|
error:
|
|
drm_dp_aux_unregister_devnode(aux);
|
|
return res;
|
|
}
|
|
|
|
int drm_dp_aux_dev_init(void)
|
|
{
|
|
int res;
|
|
|
|
drm_dp_aux_dev_class = class_create(THIS_MODULE, "drm_dp_aux_dev");
|
|
if (IS_ERR(drm_dp_aux_dev_class)) {
|
|
return PTR_ERR(drm_dp_aux_dev_class);
|
|
}
|
|
drm_dp_aux_dev_class->dev_groups = drm_dp_aux_groups;
|
|
|
|
res = register_chrdev(0, "aux", &auxdev_fops);
|
|
if (res < 0)
|
|
goto out;
|
|
drm_dev_major = res;
|
|
|
|
return 0;
|
|
out:
|
|
class_destroy(drm_dp_aux_dev_class);
|
|
return res;
|
|
}
|
|
|
|
void drm_dp_aux_dev_exit(void)
|
|
{
|
|
unregister_chrdev(drm_dev_major, "aux");
|
|
class_destroy(drm_dp_aux_dev_class);
|
|
}
|