linuxdebug/drivers/mtd/nand/raw/ingenic/ingenic_ecc.c

159 lines
3.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* JZ47xx ECC common code
*
* Copyright (c) 2015 Imagination Technologies
* Author: Alex Smith <alex.smith@imgtec.com>
*/
#include <linux/clk.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include "ingenic_ecc.h"
/**
* ingenic_ecc_calculate() - calculate ECC for a data buffer
* @ecc: ECC device.
* @params: ECC parameters.
* @buf: input buffer with raw data.
* @ecc_code: output buffer with ECC.
*
* Return: 0 on success, -ETIMEDOUT if timed out while waiting for ECC
* controller.
*/
int ingenic_ecc_calculate(struct ingenic_ecc *ecc,
struct ingenic_ecc_params *params,
const u8 *buf, u8 *ecc_code)
{
return ecc->ops->calculate(ecc, params, buf, ecc_code);
}
/**
* ingenic_ecc_correct() - detect and correct bit errors
* @ecc: ECC device.
* @params: ECC parameters.
* @buf: raw data read from the chip.
* @ecc_code: ECC read from the chip.
*
* Given the raw data and the ECC read from the NAND device, detects and
* corrects errors in the data.
*
* Return: the number of bit errors corrected, -EBADMSG if there are too many
* errors to correct or -ETIMEDOUT if we timed out waiting for the controller.
*/
int ingenic_ecc_correct(struct ingenic_ecc *ecc,
struct ingenic_ecc_params *params,
u8 *buf, u8 *ecc_code)
{
return ecc->ops->correct(ecc, params, buf, ecc_code);
}
/**
* ingenic_ecc_get() - get the ECC controller device
* @np: ECC device tree node.
*
* Gets the ECC controller device from the specified device tree node. The
* device must be released with ingenic_ecc_release() when it is no longer being
* used.
*
* Return: a pointer to ingenic_ecc, errors are encoded into the pointer.
* PTR_ERR(-EPROBE_DEFER) if the device hasn't been initialised yet.
*/
static struct ingenic_ecc *ingenic_ecc_get(struct device_node *np)
{
struct platform_device *pdev;
struct ingenic_ecc *ecc;
pdev = of_find_device_by_node(np);
if (!pdev)
return ERR_PTR(-EPROBE_DEFER);
if (!platform_get_drvdata(pdev)) {
put_device(&pdev->dev);
return ERR_PTR(-EPROBE_DEFER);
}
ecc = platform_get_drvdata(pdev);
clk_prepare_enable(ecc->clk);
return ecc;
}
/**
* of_ingenic_ecc_get() - get the ECC controller from a DT node
* @of_node: the node that contains an ecc-engine property.
*
* Get the ecc-engine property from the given device tree
* node and pass it to ingenic_ecc_get to do the work.
*
* Return: a pointer to ingenic_ecc, errors are encoded into the pointer.
* PTR_ERR(-EPROBE_DEFER) if the device hasn't been initialised yet.
*/
struct ingenic_ecc *of_ingenic_ecc_get(struct device_node *of_node)
{
struct ingenic_ecc *ecc = NULL;
struct device_node *np;
np = of_parse_phandle(of_node, "ecc-engine", 0);
/*
* If the ecc-engine property is not found, check for the deprecated
* ingenic,bch-controller property
*/
if (!np)
np = of_parse_phandle(of_node, "ingenic,bch-controller", 0);
if (np) {
ecc = ingenic_ecc_get(np);
of_node_put(np);
}
return ecc;
}
/**
* ingenic_ecc_release() - release the ECC controller device
* @ecc: ECC device.
*/
void ingenic_ecc_release(struct ingenic_ecc *ecc)
{
clk_disable_unprepare(ecc->clk);
put_device(ecc->dev);
}
int ingenic_ecc_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct ingenic_ecc *ecc;
ecc = devm_kzalloc(dev, sizeof(*ecc), GFP_KERNEL);
if (!ecc)
return -ENOMEM;
ecc->ops = device_get_match_data(dev);
if (!ecc->ops)
return -EINVAL;
ecc->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(ecc->base))
return PTR_ERR(ecc->base);
ecc->ops->disable(ecc);
ecc->clk = devm_clk_get(dev, NULL);
if (IS_ERR(ecc->clk)) {
dev_err(dev, "failed to get clock: %ld\n", PTR_ERR(ecc->clk));
return PTR_ERR(ecc->clk);
}
mutex_init(&ecc->lock);
ecc->dev = dev;
platform_set_drvdata(pdev, ecc);
return 0;
}
EXPORT_SYMBOL(ingenic_ecc_probe);