brintos

brintos / linux-shallow public Read only

0
0
Text · 3.9 KiB · 525c34c Raw
160 lines · c
1// SPDX-License-Identifier: GPL-2.02/*3 * JZ47xx ECC common code4 *5 * Copyright (c) 2015 Imagination Technologies6 * Author: Alex Smith <alex.smith@imgtec.com>7 */8 9#include <linux/clk.h>10#include <linux/init.h>11#include <linux/module.h>12#include <linux/of.h>13#include <linux/of_platform.h>14#include <linux/platform_device.h>15 16#include "ingenic_ecc.h"17 18/**19 * ingenic_ecc_calculate() - calculate ECC for a data buffer20 * @ecc: ECC device.21 * @params: ECC parameters.22 * @buf: input buffer with raw data.23 * @ecc_code: output buffer with ECC.24 *25 * Return: 0 on success, -ETIMEDOUT if timed out while waiting for ECC26 * controller.27 */28int ingenic_ecc_calculate(struct ingenic_ecc *ecc,29			  struct ingenic_ecc_params *params,30			  const u8 *buf, u8 *ecc_code)31{32	return ecc->ops->calculate(ecc, params, buf, ecc_code);33}34 35/**36 * ingenic_ecc_correct() - detect and correct bit errors37 * @ecc: ECC device.38 * @params: ECC parameters.39 * @buf: raw data read from the chip.40 * @ecc_code: ECC read from the chip.41 *42 * Given the raw data and the ECC read from the NAND device, detects and43 * corrects errors in the data.44 *45 * Return: the number of bit errors corrected, -EBADMSG if there are too many46 * errors to correct or -ETIMEDOUT if we timed out waiting for the controller.47 */48int ingenic_ecc_correct(struct ingenic_ecc *ecc,49			struct ingenic_ecc_params *params,50			u8 *buf, u8 *ecc_code)51{52	return ecc->ops->correct(ecc, params, buf, ecc_code);53}54 55/**56 * ingenic_ecc_get() - get the ECC controller device57 * @np: ECC device tree node.58 *59 * Gets the ECC controller device from the specified device tree node. The60 * device must be released with ingenic_ecc_release() when it is no longer being61 * used.62 *63 * Return: a pointer to ingenic_ecc, errors are encoded into the pointer.64 * PTR_ERR(-EPROBE_DEFER) if the device hasn't been initialised yet.65 */66static struct ingenic_ecc *ingenic_ecc_get(struct device_node *np)67{68	struct platform_device *pdev;69	struct ingenic_ecc *ecc;70 71	pdev = of_find_device_by_node(np);72	if (!pdev)73		return ERR_PTR(-EPROBE_DEFER);74 75	if (!platform_get_drvdata(pdev)) {76		put_device(&pdev->dev);77		return ERR_PTR(-EPROBE_DEFER);78	}79 80	ecc = platform_get_drvdata(pdev);81	clk_prepare_enable(ecc->clk);82 83	return ecc;84}85 86/**87 * of_ingenic_ecc_get() - get the ECC controller from a DT node88 * @of_node: the node that contains an ecc-engine property.89 *90 * Get the ecc-engine property from the given device tree91 * node and pass it to ingenic_ecc_get to do the work.92 *93 * Return: a pointer to ingenic_ecc, errors are encoded into the pointer.94 * PTR_ERR(-EPROBE_DEFER) if the device hasn't been initialised yet.95 */96struct ingenic_ecc *of_ingenic_ecc_get(struct device_node *of_node)97{98	struct ingenic_ecc *ecc = NULL;99	struct device_node *np;100 101	np = of_parse_phandle(of_node, "ecc-engine", 0);102 103	/*104	 * If the ecc-engine property is not found, check for the deprecated105	 * ingenic,bch-controller property106	 */107	if (!np)108		np = of_parse_phandle(of_node, "ingenic,bch-controller", 0);109 110	if (np) {111		ecc = ingenic_ecc_get(np);112		of_node_put(np);113	}114	return ecc;115}116 117/**118 * ingenic_ecc_release() - release the ECC controller device119 * @ecc: ECC device.120 */121void ingenic_ecc_release(struct ingenic_ecc *ecc)122{123	clk_disable_unprepare(ecc->clk);124	put_device(ecc->dev);125}126 127int ingenic_ecc_probe(struct platform_device *pdev)128{129	struct device *dev = &pdev->dev;130	struct ingenic_ecc *ecc;131 132	ecc = devm_kzalloc(dev, sizeof(*ecc), GFP_KERNEL);133	if (!ecc)134		return -ENOMEM;135 136	ecc->ops = device_get_match_data(dev);137	if (!ecc->ops)138		return -EINVAL;139 140	ecc->base = devm_platform_ioremap_resource(pdev, 0);141	if (IS_ERR(ecc->base))142		return PTR_ERR(ecc->base);143 144	ecc->ops->disable(ecc);145 146	ecc->clk = devm_clk_get(dev, NULL);147	if (IS_ERR(ecc->clk)) {148		dev_err(dev, "failed to get clock: %ld\n", PTR_ERR(ecc->clk));149		return PTR_ERR(ecc->clk);150	}151 152	mutex_init(&ecc->lock);153 154	ecc->dev = dev;155	platform_set_drvdata(pdev, ecc);156 157	return 0;158}159EXPORT_SYMBOL(ingenic_ecc_probe);160