1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * JZ47xx ECC common code 4 * 5 * Copyright (c) 2015 Imagination Technologies 6 * 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_platform.h> 13 #include <linux/platform_device.h> 14 15 #include "ingenic_ecc.h" 16 17 /** 18 * ingenic_ecc_calculate() - calculate ECC for a data buffer 19 * @ecc: ECC device. 20 * @params: ECC parameters. 21 * @buf: input buffer with raw data. 22 * @ecc_code: output buffer with ECC. 23 * 24 * Return: 0 on success, -ETIMEDOUT if timed out while waiting for ECC 25 * controller. 26 */ 27 int ingenic_ecc_calculate(struct ingenic_ecc *ecc, 28 struct ingenic_ecc_params *params, 29 const u8 *buf, u8 *ecc_code) 30 { 31 return ecc->ops->calculate(ecc, params, buf, ecc_code); 32 } 33 34 /** 35 * ingenic_ecc_correct() - detect and correct bit errors 36 * @ecc: ECC device. 37 * @params: ECC parameters. 38 * @buf: raw data read from the chip. 39 * @ecc_code: ECC read from the chip. 40 * 41 * Given the raw data and the ECC read from the NAND device, detects and 42 * corrects errors in the data. 43 * 44 * Return: the number of bit errors corrected, -EBADMSG if there are too many 45 * errors to correct or -ETIMEDOUT if we timed out waiting for the controller. 46 */ 47 int ingenic_ecc_correct(struct ingenic_ecc *ecc, 48 struct ingenic_ecc_params *params, 49 u8 *buf, u8 *ecc_code) 50 { 51 return ecc->ops->correct(ecc, params, buf, ecc_code); 52 } 53 54 /** 55 * ingenic_ecc_get() - get the ECC controller device 56 * @np: ECC device tree node. 57 * 58 * Gets the ECC controller device from the specified device tree node. The 59 * device must be released with ingenic_ecc_release() when it is no longer being 60 * used. 61 * 62 * Return: a pointer to ingenic_ecc, errors are encoded into the pointer. 63 * PTR_ERR(-EPROBE_DEFER) if the device hasn't been initialised yet. 64 */ 65 static struct ingenic_ecc *ingenic_ecc_get(struct device_node *np) 66 { 67 struct platform_device *pdev; 68 struct ingenic_ecc *ecc; 69 70 pdev = of_find_device_by_node(np); 71 if (!pdev) 72 return ERR_PTR(-EPROBE_DEFER); 73 74 if (!platform_get_drvdata(pdev)) { 75 put_device(&pdev->dev); 76 return ERR_PTR(-EPROBE_DEFER); 77 } 78 79 ecc = platform_get_drvdata(pdev); 80 clk_prepare_enable(ecc->clk); 81 82 return ecc; 83 } 84 85 /** 86 * of_ingenic_ecc_get() - get the ECC controller from a DT node 87 * @of_node: the node that contains an ecc-engine property. 88 * 89 * Get the ecc-engine property from the given device tree 90 * node and pass it to ingenic_ecc_get to do the work. 91 * 92 * Return: a pointer to ingenic_ecc, errors are encoded into the pointer. 93 * PTR_ERR(-EPROBE_DEFER) if the device hasn't been initialised yet. 94 */ 95 struct ingenic_ecc *of_ingenic_ecc_get(struct device_node *of_node) 96 { 97 struct ingenic_ecc *ecc = NULL; 98 struct device_node *np; 99 100 np = of_parse_phandle(of_node, "ecc-engine", 0); 101 102 /* 103 * If the ecc-engine property is not found, check for the deprecated 104 * ingenic,bch-controller property 105 */ 106 if (!np) 107 np = of_parse_phandle(of_node, "ingenic,bch-controller", 0); 108 109 if (np) { 110 ecc = ingenic_ecc_get(np); 111 of_node_put(np); 112 } 113 return ecc; 114 } 115 116 /** 117 * ingenic_ecc_release() - release the ECC controller device 118 * @ecc: ECC device. 119 */ 120 void ingenic_ecc_release(struct ingenic_ecc *ecc) 121 { 122 clk_disable_unprepare(ecc->clk); 123 put_device(ecc->dev); 124 } 125 126 int ingenic_ecc_probe(struct platform_device *pdev) 127 { 128 struct device *dev = &pdev->dev; 129 struct ingenic_ecc *ecc; 130 131 ecc = devm_kzalloc(dev, sizeof(*ecc), GFP_KERNEL); 132 if (!ecc) 133 return -ENOMEM; 134 135 ecc->ops = device_get_match_data(dev); 136 if (!ecc->ops) 137 return -EINVAL; 138 139 ecc->base = devm_platform_ioremap_resource(pdev, 0); 140 if (IS_ERR(ecc->base)) 141 return PTR_ERR(ecc->base); 142 143 ecc->ops->disable(ecc); 144 145 ecc->clk = devm_clk_get(dev, NULL); 146 if (IS_ERR(ecc->clk)) { 147 dev_err(dev, "failed to get clock: %ld\n", PTR_ERR(ecc->clk)); 148 return PTR_ERR(ecc->clk); 149 } 150 151 mutex_init(&ecc->lock); 152 153 ecc->dev = dev; 154 platform_set_drvdata(pdev, ecc); 155 156 return 0; 157 } 158 EXPORT_SYMBOL(ingenic_ecc_probe); 159