linux/drivers/accel/drm_accel.c

// SPDX-License-Identifier: GPL-2.0

/*
 * Copyright 2022 HabanaLabs, Ltd.
 * All Rights Reserved.
 *
 */

#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/idr.h>

#include <drm/drm_accel.h>
#include <drm/drm_auth.h>
#include <drm/drm_debugfs.h>
#include <drm/drm_drv.h>
#include <drm/drm_file.h>
#include <drm/drm_ioctl.h>
#include <drm/drm_print.h>

static DEFINE_SPINLOCK(accel_minor_lock);
static struct idr accel_minors_idr;

static struct dentry *accel_debugfs_root;

static const struct device_type accel_sysfs_device_minor = …;

static char *accel_devnode(const struct device *dev, umode_t *mode)
{ … }

static const struct class accel_class = …;

static int accel_sysfs_init(void)
{ … }

static void accel_sysfs_destroy(void)
{ … }

static int accel_name_info(struct seq_file *m, void *data)
{ … }

static const struct drm_info_list accel_debugfs_list[] = …;
#define ACCEL_DEBUGFS_ENTRIES …

/**
 * accel_debugfs_init() - Initialize debugfs for device
 * @dev: Pointer to the device instance.
 *
 * This function creates a root directory for the device in debugfs.
 */
void accel_debugfs_init(struct drm_device *dev)
{ … }

/**
 * accel_debugfs_register() - Register debugfs for device
 * @dev: Pointer to the device instance.
 *
 * Creates common files for accelerators.
 */
void accel_debugfs_register(struct drm_device *dev)
{ … }

/**
 * accel_set_device_instance_params() - Set some device parameters for accel device
 * @kdev: Pointer to the device instance.
 * @index: The minor's index
 *
 * This function creates the dev_t of the device using the accel major and
 * the device's minor number. In addition, it sets the class and type of the
 * device instance to the accel sysfs class and device type, respectively.
 */
void accel_set_device_instance_params(struct device *kdev, int index)
{ … }

/**
 * accel_minor_alloc() - Allocates a new accel minor
 *
 * This function access the accel minors idr and allocates from it
 * a new id to represent a new accel minor
 *
 * Return: A new id on success or error code in case idr_alloc failed
 */
int accel_minor_alloc(void)
{ … }

/**
 * accel_minor_remove() - Remove an accel minor
 * @index: The minor id to remove.
 *
 * This function access the accel minors idr and removes from
 * it the member with the id that is passed to this function.
 */
void accel_minor_remove(int index)
{ … }

/**
 * accel_minor_replace() - Replace minor pointer in accel minors idr.
 * @minor: Pointer to the new minor.
 * @index: The minor id to replace.
 *
 * This function access the accel minors idr structure and replaces the pointer
 * that is associated with an existing id. Because the minor pointer can be
 * NULL, we need to explicitly pass the index.
 *
 * Return: 0 for success, negative value for error
 */
void accel_minor_replace(struct drm_minor *minor, int index)
{ … }

/*
 * Looks up the given minor-ID and returns the respective DRM-minor object. The
 * refence-count of the underlying device is increased so you must release this
 * object with accel_minor_release().
 *
 * The object can be only a drm_minor that represents an accel device.
 *
 * As long as you hold this minor, it is guaranteed that the object and the
 * minor->dev pointer will stay valid! However, the device may get unplugged and
 * unregistered while you hold the minor.
 */
static struct drm_minor *accel_minor_acquire(unsigned int minor_id)
{ … }

static void accel_minor_release(struct drm_minor *minor)
{ … }

/**
 * accel_open - open method for ACCEL file
 * @inode: device inode
 * @filp: file pointer.
 *
 * This function must be used by drivers as their &file_operations.open method.
 * It looks up the correct ACCEL device and instantiates all the per-file
 * resources for it. It also calls the &drm_driver.open driver callback.
 *
 * Return: 0 on success or negative errno value on failure.
 */
int accel_open(struct inode *inode, struct file *filp)
{ … }
EXPORT_SYMBOL_GPL(…);

static int accel_stub_open(struct inode *inode, struct file *filp)
{ … }

static const struct file_operations accel_stub_fops = …;

void accel_core_exit(void)
{ … }

int __init accel_core_init(void)
{ … }