1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Generic NAND driver 4 * 5 * Author: Vitaly Wool <vitalywool@gmail.com> 6 */ 7 8 #include <linux/err.h> 9 #include <linux/io.h> 10 #include <linux/module.h> 11 #include <linux/platform_device.h> 12 #include <linux/slab.h> 13 #include <linux/mtd/mtd.h> 14 #include <linux/mtd/platnand.h> 15 16 struct plat_nand_data { 17 struct nand_controller controller; 18 struct nand_chip chip; 19 void __iomem *io_base; 20 }; 21 22 static int plat_nand_attach_chip(struct nand_chip *chip) 23 { 24 if (chip->ecc.engine_type == NAND_ECC_ENGINE_TYPE_SOFT && 25 chip->ecc.algo == NAND_ECC_ALGO_UNKNOWN) 26 chip->ecc.algo = NAND_ECC_ALGO_HAMMING; 27 28 return 0; 29 } 30 31 static const struct nand_controller_ops plat_nand_ops = { 32 .attach_chip = plat_nand_attach_chip, 33 }; 34 35 /* 36 * Probe for the NAND device. 37 */ 38 static int plat_nand_probe(struct platform_device *pdev) 39 { 40 struct platform_nand_data *pdata = dev_get_platdata(&pdev->dev); 41 struct plat_nand_data *data; 42 struct mtd_info *mtd; 43 const char **part_types; 44 int err = 0; 45 46 if (!pdata) { 47 dev_err(&pdev->dev, "platform_nand_data is missing\n"); 48 return -EINVAL; 49 } 50 51 if (pdata->chip.nr_chips < 1) { 52 dev_err(&pdev->dev, "invalid number of chips specified\n"); 53 return -EINVAL; 54 } 55 56 /* Allocate memory for the device structure (and zero it) */ 57 data = devm_kzalloc(&pdev->dev, sizeof(struct plat_nand_data), 58 GFP_KERNEL); 59 if (!data) 60 return -ENOMEM; 61 62 data->controller.ops = &plat_nand_ops; 63 nand_controller_init(&data->controller); 64 data->chip.controller = &data->controller; 65 66 data->io_base = devm_platform_ioremap_resource(pdev, 0); 67 if (IS_ERR(data->io_base)) 68 return PTR_ERR(data->io_base); 69 70 nand_set_flash_node(&data->chip, pdev->dev.of_node); 71 mtd = nand_to_mtd(&data->chip); 72 mtd->dev.parent = &pdev->dev; 73 74 data->chip.legacy.IO_ADDR_R = data->io_base; 75 data->chip.legacy.IO_ADDR_W = data->io_base; 76 data->chip.legacy.cmd_ctrl = pdata->ctrl.cmd_ctrl; 77 data->chip.legacy.dev_ready = pdata->ctrl.dev_ready; 78 data->chip.legacy.select_chip = pdata->ctrl.select_chip; 79 data->chip.legacy.write_buf = pdata->ctrl.write_buf; 80 data->chip.legacy.read_buf = pdata->ctrl.read_buf; 81 data->chip.legacy.chip_delay = pdata->chip.chip_delay; 82 data->chip.options |= pdata->chip.options; 83 data->chip.bbt_options |= pdata->chip.bbt_options; 84 85 platform_set_drvdata(pdev, data); 86 87 /* Handle any platform specific setup */ 88 if (pdata->ctrl.probe) { 89 err = pdata->ctrl.probe(pdev); 90 if (err) 91 goto out; 92 } 93 94 /* 95 * This driver assumes that the default ECC engine should be TYPE_SOFT. 96 * Set ->engine_type before registering the NAND devices in order to 97 * provide a driver specific default value. 98 */ 99 data->chip.ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT; 100 101 /* Scan to find existence of the device */ 102 err = nand_scan(&data->chip, pdata->chip.nr_chips); 103 if (err) 104 goto out; 105 106 part_types = pdata->chip.part_probe_types; 107 108 err = mtd_device_parse_register(mtd, part_types, NULL, 109 pdata->chip.partitions, 110 pdata->chip.nr_partitions); 111 112 if (!err) 113 return err; 114 115 nand_cleanup(&data->chip); 116 out: 117 if (pdata->ctrl.remove) 118 pdata->ctrl.remove(pdev); 119 return err; 120 } 121 122 /* 123 * Remove a NAND device. 124 */ 125 static int plat_nand_remove(struct platform_device *pdev) 126 { 127 struct plat_nand_data *data = platform_get_drvdata(pdev); 128 struct platform_nand_data *pdata = dev_get_platdata(&pdev->dev); 129 struct nand_chip *chip = &data->chip; 130 int ret; 131 132 ret = mtd_device_unregister(nand_to_mtd(chip)); 133 WARN_ON(ret); 134 nand_cleanup(chip); 135 if (pdata->ctrl.remove) 136 pdata->ctrl.remove(pdev); 137 138 return 0; 139 } 140 141 static const struct of_device_id plat_nand_match[] = { 142 { .compatible = "gen_nand" }, 143 {}, 144 }; 145 MODULE_DEVICE_TABLE(of, plat_nand_match); 146 147 static struct platform_driver plat_nand_driver = { 148 .probe = plat_nand_probe, 149 .remove = plat_nand_remove, 150 .driver = { 151 .name = "gen_nand", 152 .of_match_table = plat_nand_match, 153 }, 154 }; 155 156 module_platform_driver(plat_nand_driver); 157 158 MODULE_LICENSE("GPL"); 159 MODULE_AUTHOR("Vitaly Wool"); 160 MODULE_DESCRIPTION("Simple generic NAND driver"); 161 MODULE_ALIAS("platform:gen_nand"); 162