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
plat_nand_attach_chip(struct nand_chip * chip)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 */
plat_nand_probe(struct platform_device * pdev)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 */
plat_nand_remove(struct platform_device * pdev)125 static 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(&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
139 static const struct of_device_id plat_nand_match[] = {
140 { .compatible = "gen_nand" },
141 {},
142 };
143 MODULE_DEVICE_TABLE(of, plat_nand_match);
144
145 static 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
154 module_platform_driver(plat_nand_driver);
155
156 MODULE_LICENSE("GPL");
157 MODULE_AUTHOR("Vitaly Wool");
158 MODULE_DESCRIPTION("Simple generic NAND driver");
159 MODULE_ALIAS("platform:gen_nand");
160