xref: /openbmc/linux/drivers/mtd/nand/raw/plat_nand.c (revision 249592bf)
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 	chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT;
25 
26 	if (chip->ecc.algo == NAND_ECC_ALGO_UNKNOWN)
27 		chip->ecc.algo = NAND_ECC_ALGO_HAMMING;
28 
29 	return 0;
30 }
31 
32 static const struct nand_controller_ops plat_nand_ops = {
33 	.attach_chip = plat_nand_attach_chip,
34 };
35 
36 /*
37  * Probe for the NAND device.
38  */
39 static int plat_nand_probe(struct platform_device *pdev)
40 {
41 	struct platform_nand_data *pdata = dev_get_platdata(&pdev->dev);
42 	struct plat_nand_data *data;
43 	struct mtd_info *mtd;
44 	struct resource *res;
45 	const char **part_types;
46 	int err = 0;
47 
48 	if (!pdata) {
49 		dev_err(&pdev->dev, "platform_nand_data is missing\n");
50 		return -EINVAL;
51 	}
52 
53 	if (pdata->chip.nr_chips < 1) {
54 		dev_err(&pdev->dev, "invalid number of chips specified\n");
55 		return -EINVAL;
56 	}
57 
58 	/* Allocate memory for the device structure (and zero it) */
59 	data = devm_kzalloc(&pdev->dev, sizeof(struct plat_nand_data),
60 			    GFP_KERNEL);
61 	if (!data)
62 		return -ENOMEM;
63 
64 	data->controller.ops = &plat_nand_ops;
65 	nand_controller_init(&data->controller);
66 	data->chip.controller = &data->controller;
67 
68 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
69 	data->io_base = devm_ioremap_resource(&pdev->dev, res);
70 	if (IS_ERR(data->io_base))
71 		return PTR_ERR(data->io_base);
72 
73 	nand_set_flash_node(&data->chip, pdev->dev.of_node);
74 	mtd = nand_to_mtd(&data->chip);
75 	mtd->dev.parent = &pdev->dev;
76 
77 	data->chip.legacy.IO_ADDR_R = data->io_base;
78 	data->chip.legacy.IO_ADDR_W = data->io_base;
79 	data->chip.legacy.cmd_ctrl = pdata->ctrl.cmd_ctrl;
80 	data->chip.legacy.dev_ready = pdata->ctrl.dev_ready;
81 	data->chip.legacy.select_chip = pdata->ctrl.select_chip;
82 	data->chip.legacy.write_buf = pdata->ctrl.write_buf;
83 	data->chip.legacy.read_buf = pdata->ctrl.read_buf;
84 	data->chip.legacy.chip_delay = pdata->chip.chip_delay;
85 	data->chip.options |= pdata->chip.options;
86 	data->chip.bbt_options |= pdata->chip.bbt_options;
87 
88 	platform_set_drvdata(pdev, data);
89 
90 	/* Handle any platform specific setup */
91 	if (pdata->ctrl.probe) {
92 		err = pdata->ctrl.probe(pdev);
93 		if (err)
94 			goto out;
95 	}
96 
97 	/* Scan to find existence of the device */
98 	err = nand_scan(&data->chip, pdata->chip.nr_chips);
99 	if (err)
100 		goto out;
101 
102 	part_types = pdata->chip.part_probe_types;
103 
104 	err = mtd_device_parse_register(mtd, part_types, NULL,
105 					pdata->chip.partitions,
106 					pdata->chip.nr_partitions);
107 
108 	if (!err)
109 		return err;
110 
111 	nand_cleanup(&data->chip);
112 out:
113 	if (pdata->ctrl.remove)
114 		pdata->ctrl.remove(pdev);
115 	return err;
116 }
117 
118 /*
119  * Remove a NAND device.
120  */
121 static int plat_nand_remove(struct platform_device *pdev)
122 {
123 	struct plat_nand_data *data = platform_get_drvdata(pdev);
124 	struct platform_nand_data *pdata = dev_get_platdata(&pdev->dev);
125 	struct nand_chip *chip = &data->chip;
126 	int ret;
127 
128 	ret = mtd_device_unregister(nand_to_mtd(chip));
129 	WARN_ON(ret);
130 	nand_cleanup(chip);
131 	if (pdata->ctrl.remove)
132 		pdata->ctrl.remove(pdev);
133 
134 	return 0;
135 }
136 
137 static const struct of_device_id plat_nand_match[] = {
138 	{ .compatible = "gen_nand" },
139 	{},
140 };
141 MODULE_DEVICE_TABLE(of, plat_nand_match);
142 
143 static struct platform_driver plat_nand_driver = {
144 	.probe	= plat_nand_probe,
145 	.remove	= plat_nand_remove,
146 	.driver	= {
147 		.name		= "gen_nand",
148 		.of_match_table = plat_nand_match,
149 	},
150 };
151 
152 module_platform_driver(plat_nand_driver);
153 
154 MODULE_LICENSE("GPL");
155 MODULE_AUTHOR("Vitaly Wool");
156 MODULE_DESCRIPTION("Simple generic NAND driver");
157 MODULE_ALIAS("platform:gen_nand");
158