diff options
Diffstat (limited to 'drivers/gpu/drm/msm/disp/dpu1/dpu_hw_blk.c')
| -rw-r--r-- | drivers/gpu/drm/msm/disp/dpu1/dpu_hw_blk.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_blk.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_blk.c new file mode 100644 index 000000000000..58d29e43faef --- /dev/null +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_blk.c @@ -0,0 +1,155 @@ +/* Copyright (c) 2017-2018, The Linux Foundation. All rights reserved. + * + * 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. + */ + +#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 + * return: 0 if success; error code otherwise + */ +int dpu_hw_blk_init(struct dpu_hw_blk *hw_blk, u32 type, int id, + struct dpu_hw_blk_ops *ops) +{ + if (!hw_blk) { + pr_err("invalid parameters\n"); + return -EINVAL; + } + + 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); + + return 0; +} + +/** + * 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); +} |