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
16struct plat_nand_data {
17 struct nand_controller controller;
18 struct nand_chip chip;
19 void __iomem *io_base;
20};
21
22static 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
31static 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 */
38static int plat_nand_probe(struct platform_device *pdev)
39{
40 struct platform_nand_data *pdata = dev_get_platdata(dev: &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(dev: &pdev->dev, size: 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(nfc: &data->controller);
64 data->chip.controller = &data->controller;
65
66 data->io_base = devm_platform_ioremap_resource(pdev, index: 0);
67 if (IS_ERR(ptr: data->io_base))
68 return PTR_ERR(ptr: data->io_base);
69
70 nand_set_flash_node(chip: &data->chip, np: pdev->dev.of_node);
71 mtd = nand_to_mtd(chip: &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(chip: &data->chip, max_chips: 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_probe_types: part_types, NULL,
109 defparts: pdata->chip.partitions,
110 defnr_parts: pdata->chip.nr_partitions);
111
112 if (!err)
113 return err;
114
115 nand_cleanup(chip: &data->chip);
116out:
117 if (pdata->ctrl.remove)
118 pdata->ctrl.remove(pdev);
119 return err;
120}
121
122/*
123 * Remove a NAND device.
124 */
125static void 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(dev: &pdev->dev);
129 struct nand_chip *chip = &data->chip;
130 int ret;
131
132 ret = mtd_device_unregister(master: nand_to_mtd(chip));
133 WARN_ON(ret);
134 nand_cleanup(chip);
135 if (pdata->ctrl.remove)
136 pdata->ctrl.remove(pdev);
137}
138
139static const struct of_device_id plat_nand_match[] = {
140 { .compatible = "gen_nand" },
141 {},
142};
143MODULE_DEVICE_TABLE(of, plat_nand_match);
144
145static struct platform_driver plat_nand_driver = {
146 .probe = plat_nand_probe,
147 .remove_new = plat_nand_remove,
148 .driver = {
149 .name = "gen_nand",
150 .of_match_table = plat_nand_match,
151 },
152};
153
154module_platform_driver(plat_nand_driver);
155
156MODULE_LICENSE("GPL");
157MODULE_AUTHOR("Vitaly Wool");
158MODULE_DESCRIPTION("Simple generic NAND driver");
159MODULE_ALIAS("platform:gen_nand");
160

source code of linux/drivers/mtd/nand/raw/plat_nand.c