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 EXPORT_SYMBOL(ingenic_ecc_calculate); 34 35 /** 36 * ingenic_ecc_correct() - detect and correct bit errors 37 * @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 and 43 * corrects errors in the data. 44 * 45 * Return: the number of bit errors corrected, -EBADMSG if there are too many 46 * errors to correct or -ETIMEDOUT if we timed out waiting for the controller. 47 */ 48 int 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 EXPORT_SYMBOL(ingenic_ecc_correct); 55 56 /** 57 * ingenic_ecc_get() - get the ECC controller device 58 * @np: ECC device tree node. 59 * 60 * Gets the ECC controller device from the specified device tree node. The 61 * device must be released with ingenic_ecc_release() when it is no longer being 62 * used. 63 * 64 * Return: a pointer to ingenic_ecc, errors are encoded into the pointer. 65 * PTR_ERR(-EPROBE_DEFER) if the device hasn't been initialised yet. 66 */ 67 static struct ingenic_ecc *ingenic_ecc_get(struct device_node *np) 68 { 69 struct platform_device *pdev; 70 struct ingenic_ecc *ecc; 71 72 pdev = of_find_device_by_node(np); 73 if (!pdev || !platform_get_drvdata(pdev)) 74 return ERR_PTR(-EPROBE_DEFER); 75 76 get_device(&pdev->dev); 77 78 ecc = platform_get_drvdata(pdev); 79 clk_prepare_enable(ecc->clk); 80 81 return ecc; 82 } 83 84 /** 85 * of_ingenic_ecc_get() - get the ECC controller from a DT node 86 * @of_node: the node that contains an ecc-engine property. 87 * 88 * Get the ecc-engine property from the given device tree 89 * node and pass it to ingenic_ecc_get to do the work. 90 * 91 * Return: a pointer to ingenic_ecc, errors are encoded into the pointer. 92 * PTR_ERR(-EPROBE_DEFER) if the device hasn't been initialised yet. 93 */ 94 struct ingenic_ecc *of_ingenic_ecc_get(struct device_node *of_node) 95 { 96 struct ingenic_ecc *ecc = NULL; 97 struct device_node *np; 98 99 np = of_parse_phandle(of_node, "ecc-engine", 0); 100 101 /* 102 * If the ecc-engine property is not found, check for the deprecated 103 * ingenic,bch-controller property 104 */ 105 if (!np) 106 np = of_parse_phandle(of_node, "ingenic,bch-controller", 0); 107 108 if (np) { 109 ecc = ingenic_ecc_get(np); 110 of_node_put(np); 111 } 112 return ecc; 113 } 114 EXPORT_SYMBOL(of_ingenic_ecc_get); 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 EXPORT_SYMBOL(ingenic_ecc_release); 126 127 int ingenic_ecc_probe(struct platform_device *pdev) 128 { 129 struct device *dev = &pdev->dev; 130 struct ingenic_ecc *ecc; 131 struct resource *res; 132 133 ecc = devm_kzalloc(dev, sizeof(*ecc), GFP_KERNEL); 134 if (!ecc) 135 return -ENOMEM; 136 137 ecc->ops = device_get_match_data(dev); 138 if (!ecc->ops) 139 return -EINVAL; 140 141 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 142 ecc->base = devm_ioremap_resource(dev, res); 143 if (IS_ERR(ecc->base)) 144 return PTR_ERR(ecc->base); 145 146 ecc->ops->disable(ecc); 147 148 ecc->clk = devm_clk_get(dev, NULL); 149 if (IS_ERR(ecc->clk)) { 150 dev_err(dev, "failed to get clock: %ld\n", PTR_ERR(ecc->clk)); 151 return PTR_ERR(ecc->clk); 152 } 153 154 mutex_init(&ecc->lock); 155 156 ecc->dev = dev; 157 platform_set_drvdata(pdev, ecc); 158 159 return 0; 160 } 161 EXPORT_SYMBOL(ingenic_ecc_probe); 162 163 MODULE_AUTHOR("Alex Smith <alex@alex-smith.me.uk>"); 164 MODULE_AUTHOR("Harvey Hunt <harveyhuntnexus@gmail.com>"); 165 MODULE_DESCRIPTION("Ingenic ECC common driver"); 166 MODULE_LICENSE("GPL v2"); 167