183 строки
4.2 KiB
C
183 строки
4.2 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* rcar-fcp.c -- R-Car Frame Compression Processor Driver
|
|
*
|
|
* Copyright (C) 2016 Renesas Electronics Corporation
|
|
*
|
|
* Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/dma-mapping.h>
|
|
#include <linux/list.h>
|
|
#include <linux/module.h>
|
|
#include <linux/mod_devicetable.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/pm_runtime.h>
|
|
#include <linux/slab.h>
|
|
|
|
#include <media/rcar-fcp.h>
|
|
|
|
struct rcar_fcp_device {
|
|
struct list_head list;
|
|
struct device *dev;
|
|
};
|
|
|
|
static LIST_HEAD(fcp_devices);
|
|
static DEFINE_MUTEX(fcp_lock);
|
|
|
|
/* -----------------------------------------------------------------------------
|
|
* Public API
|
|
*/
|
|
|
|
/**
|
|
* rcar_fcp_get - Find and acquire a reference to an FCP instance
|
|
* @np: Device node of the FCP instance
|
|
*
|
|
* Search the list of registered FCP instances for the instance corresponding to
|
|
* the given device node.
|
|
*
|
|
* Return a pointer to the FCP instance, or an ERR_PTR if the instance can't be
|
|
* found.
|
|
*/
|
|
struct rcar_fcp_device *rcar_fcp_get(const struct device_node *np)
|
|
{
|
|
struct rcar_fcp_device *fcp;
|
|
|
|
mutex_lock(&fcp_lock);
|
|
|
|
list_for_each_entry(fcp, &fcp_devices, list) {
|
|
if (fcp->dev->of_node != np)
|
|
continue;
|
|
|
|
get_device(fcp->dev);
|
|
goto done;
|
|
}
|
|
|
|
fcp = ERR_PTR(-EPROBE_DEFER);
|
|
|
|
done:
|
|
mutex_unlock(&fcp_lock);
|
|
return fcp;
|
|
}
|
|
EXPORT_SYMBOL_GPL(rcar_fcp_get);
|
|
|
|
/**
|
|
* rcar_fcp_put - Release a reference to an FCP instance
|
|
* @fcp: The FCP instance
|
|
*
|
|
* Release the FCP instance acquired by a call to rcar_fcp_get().
|
|
*/
|
|
void rcar_fcp_put(struct rcar_fcp_device *fcp)
|
|
{
|
|
if (fcp)
|
|
put_device(fcp->dev);
|
|
}
|
|
EXPORT_SYMBOL_GPL(rcar_fcp_put);
|
|
|
|
struct device *rcar_fcp_get_device(struct rcar_fcp_device *fcp)
|
|
{
|
|
return fcp->dev;
|
|
}
|
|
EXPORT_SYMBOL_GPL(rcar_fcp_get_device);
|
|
|
|
/**
|
|
* rcar_fcp_enable - Enable an FCP
|
|
* @fcp: The FCP instance
|
|
*
|
|
* Before any memory access through an FCP is performed by a module, the FCP
|
|
* must be enabled by a call to this function. The enable calls are reference
|
|
* counted, each successful call must be followed by one rcar_fcp_disable()
|
|
* call when no more memory transfer can occur through the FCP.
|
|
*
|
|
* Return 0 on success or a negative error code if an error occurs. The enable
|
|
* reference count isn't increased when this function returns an error.
|
|
*/
|
|
int rcar_fcp_enable(struct rcar_fcp_device *fcp)
|
|
{
|
|
if (!fcp)
|
|
return 0;
|
|
|
|
return pm_runtime_resume_and_get(fcp->dev);
|
|
}
|
|
EXPORT_SYMBOL_GPL(rcar_fcp_enable);
|
|
|
|
/**
|
|
* rcar_fcp_disable - Disable an FCP
|
|
* @fcp: The FCP instance
|
|
*
|
|
* This function is the counterpart of rcar_fcp_enable(). As enable calls are
|
|
* reference counted a disable call may not disable the FCP synchronously.
|
|
*/
|
|
void rcar_fcp_disable(struct rcar_fcp_device *fcp)
|
|
{
|
|
if (fcp)
|
|
pm_runtime_put(fcp->dev);
|
|
}
|
|
EXPORT_SYMBOL_GPL(rcar_fcp_disable);
|
|
|
|
/* -----------------------------------------------------------------------------
|
|
* Platform Driver
|
|
*/
|
|
|
|
static int rcar_fcp_probe(struct platform_device *pdev)
|
|
{
|
|
struct rcar_fcp_device *fcp;
|
|
|
|
fcp = devm_kzalloc(&pdev->dev, sizeof(*fcp), GFP_KERNEL);
|
|
if (fcp == NULL)
|
|
return -ENOMEM;
|
|
|
|
fcp->dev = &pdev->dev;
|
|
|
|
dma_set_max_seg_size(fcp->dev, UINT_MAX);
|
|
|
|
pm_runtime_enable(&pdev->dev);
|
|
|
|
mutex_lock(&fcp_lock);
|
|
list_add_tail(&fcp->list, &fcp_devices);
|
|
mutex_unlock(&fcp_lock);
|
|
|
|
platform_set_drvdata(pdev, fcp);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int rcar_fcp_remove(struct platform_device *pdev)
|
|
{
|
|
struct rcar_fcp_device *fcp = platform_get_drvdata(pdev);
|
|
|
|
mutex_lock(&fcp_lock);
|
|
list_del(&fcp->list);
|
|
mutex_unlock(&fcp_lock);
|
|
|
|
pm_runtime_disable(&pdev->dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id rcar_fcp_of_match[] = {
|
|
{ .compatible = "renesas,fcpf" },
|
|
{ .compatible = "renesas,fcpv" },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(of, rcar_fcp_of_match);
|
|
|
|
static struct platform_driver rcar_fcp_platform_driver = {
|
|
.probe = rcar_fcp_probe,
|
|
.remove = rcar_fcp_remove,
|
|
.driver = {
|
|
.name = "rcar-fcp",
|
|
.of_match_table = rcar_fcp_of_match,
|
|
.suppress_bind_attrs = true,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(rcar_fcp_platform_driver);
|
|
|
|
MODULE_ALIAS("rcar-fcp");
|
|
MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
|
|
MODULE_DESCRIPTION("Renesas FCP Driver");
|
|
MODULE_LICENSE("GPL");
|