linux/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_blk.c
Thomas Gleixner 97fb5e8d9b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 and
  only version 2 as published by the free software foundation this
  program is distributed in the hope that it will be useful but
  without any warranty without even the implied warranty of
  merchantability or fitness for a particular purpose see the gnu
  general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 294 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.825281744@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:37 +02:00

140 lines
3.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
*/
#define pr_fmt(fmt) "[drm:%s:%d] " fmt, __func__, __LINE__
#include <linux/mutex.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include "dpu_hw_mdss.h"
#include "dpu_hw_blk.h"
/* Serialization lock for dpu_hw_blk_list */
static DEFINE_MUTEX(dpu_hw_blk_lock);
/* List of all hw block objects */
static LIST_HEAD(dpu_hw_blk_list);
/**
* dpu_hw_blk_init - initialize hw block object
* @type: hw block type - enum dpu_hw_blk_type
* @id: instance id of the hw block
* @ops: Pointer to block operations
*/
void dpu_hw_blk_init(struct dpu_hw_blk *hw_blk, u32 type, int id,
struct dpu_hw_blk_ops *ops)
{
INIT_LIST_HEAD(&hw_blk->list);
hw_blk->type = type;
hw_blk->id = id;
atomic_set(&hw_blk->refcount, 0);
if (ops)
hw_blk->ops = *ops;
mutex_lock(&dpu_hw_blk_lock);
list_add(&hw_blk->list, &dpu_hw_blk_list);
mutex_unlock(&dpu_hw_blk_lock);
}
/**
* dpu_hw_blk_destroy - destroy hw block object.
* @hw_blk: pointer to hw block object
* return: none
*/
void dpu_hw_blk_destroy(struct dpu_hw_blk *hw_blk)
{
if (!hw_blk) {
pr_err("invalid parameters\n");
return;
}
if (atomic_read(&hw_blk->refcount))
pr_err("hw_blk:%d.%d invalid refcount\n", hw_blk->type,
hw_blk->id);
mutex_lock(&dpu_hw_blk_lock);
list_del(&hw_blk->list);
mutex_unlock(&dpu_hw_blk_lock);
}
/**
* dpu_hw_blk_get - get hw_blk from free pool
* @hw_blk: if specified, increment reference count only
* @type: if hw_blk is not specified, allocate the next available of this type
* @id: if specified (>= 0), allocate the given instance of the above type
* return: pointer to hw block object
*/
struct dpu_hw_blk *dpu_hw_blk_get(struct dpu_hw_blk *hw_blk, u32 type, int id)
{
struct dpu_hw_blk *curr;
int rc, refcount;
if (!hw_blk) {
mutex_lock(&dpu_hw_blk_lock);
list_for_each_entry(curr, &dpu_hw_blk_list, list) {
if ((curr->type != type) ||
(id >= 0 && curr->id != id) ||
(id < 0 &&
atomic_read(&curr->refcount)))
continue;
hw_blk = curr;
break;
}
mutex_unlock(&dpu_hw_blk_lock);
}
if (!hw_blk) {
pr_debug("no hw_blk:%d\n", type);
return NULL;
}
refcount = atomic_inc_return(&hw_blk->refcount);
if (refcount == 1 && hw_blk->ops.start) {
rc = hw_blk->ops.start(hw_blk);
if (rc) {
pr_err("failed to start hw_blk:%d rc:%d\n", type, rc);
goto error_start;
}
}
pr_debug("hw_blk:%d.%d refcount:%d\n", hw_blk->type,
hw_blk->id, refcount);
return hw_blk;
error_start:
dpu_hw_blk_put(hw_blk);
return ERR_PTR(rc);
}
/**
* dpu_hw_blk_put - put hw_blk to free pool if decremented refcount is zero
* @hw_blk: hw block to be freed
* @free_blk: function to be called when reference count goes to zero
*/
void dpu_hw_blk_put(struct dpu_hw_blk *hw_blk)
{
if (!hw_blk) {
pr_err("invalid parameters\n");
return;
}
pr_debug("hw_blk:%d.%d refcount:%d\n", hw_blk->type, hw_blk->id,
atomic_read(&hw_blk->refcount));
if (!atomic_read(&hw_blk->refcount)) {
pr_err("hw_blk:%d.%d invalid put\n", hw_blk->type, hw_blk->id);
return;
}
if (atomic_dec_return(&hw_blk->refcount))
return;
if (hw_blk->ops.stop)
hw_blk->ops.stop(hw_blk);
}