xref: /openbmc/linux/drivers/mtd/nand/raw/plat_nand.c (revision 07d9a767)
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 	chip->ecc.algo = NAND_ECC_ALGO_HAMMING;
26 
27 	return 0;
28 }
29 
30 static const struct nand_controller_ops plat_nand_ops = {
31 	.attach_chip = plat_nand_attach_chip,
32 };
33 
34 /*
35  * Probe for the NAND device.
36  */
37 static int plat_nand_probe(struct platform_device *pdev)
38 {
39 	struct platform_nand_data *pdata = dev_get_platdata(&pdev->dev);
40 	struct plat_nand_data *data;
41 	struct mtd_info *mtd;
42 	struct resource *res;
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 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
67 	data->io_base = devm_ioremap_resource(&pdev->dev, res);
68 	if (IS_ERR(data->io_base))
69 		return PTR_ERR(data->io_base);
70 
71 	nand_set_flash_node(&data->chip, pdev->dev.of_node);
72 	mtd = nand_to_mtd(&data->chip);
73 	mtd->dev.parent = &pdev->dev;
74 
75 	data->chip.legacy.IO_ADDR_R = data->io_base;
76 	data->chip.legacy.IO_ADDR_W = data->io_base;
77 	data->chip.legacy.cmd_ctrl = pdata->ctrl.cmd_ctrl;
78 	data->chip.legacy.dev_ready = pdata->ctrl.dev_ready;
79 	data->chip.legacy.select_chip = pdata->ctrl.select_chip;
80 	data->chip.legacy.write_buf = pdata->ctrl.write_buf;
81 	data->chip.legacy.read_buf = pdata->ctrl.read_buf;
82 	data->chip.legacy.chip_delay = pdata->chip.chip_delay;
83 	data->chip.options |= pdata->chip.options;
84 	data->chip.bbt_options |= pdata->chip.bbt_options;
85 
86 	platform_set_drvdata(pdev, data);
87 
88 	/* Handle any platform specific setup */
89 	if (pdata->ctrl.probe) {
90 		err = pdata->ctrl.probe(pdev);
91 		if (err)
92 			goto out;
93 	}
94 
95 	/* Scan to find existence of the device */
96 	err = nand_scan(&data->chip, pdata->chip.nr_chips);
97 	if (err)
98 		goto out;
99 
100 	part_types = pdata->chip.part_probe_types;
101 
102 	err = mtd_device_parse_register(mtd, part_types, NULL,
103 					pdata->chip.partitions,
104 					pdata->chip.nr_partitions);
105 
106 	if (!err)
107 		return err;
108 
109 	nand_cleanup(&data->chip);
110 out:
111 	if (pdata->ctrl.remove)
112 		pdata->ctrl.remove(pdev);
113 	return err;
114 }
115 
116 /*
117  * Remove a NAND device.
118  */
119 static int plat_nand_remove(struct platform_device *pdev)
120 {
121 	struct plat_nand_data *data = platform_get_drvdata(pdev);
122 	struct platform_nand_data *pdata = dev_get_platdata(&pdev->dev);
123 	struct nand_chip *chip = &data->chip;
124 	int ret;
125 
126 	ret = mtd_device_unregister(nand_to_mtd(chip));
127 	WARN_ON(ret);
128 	nand_cleanup(chip);
129 	if (pdata->ctrl.remove)
130 		pdata->ctrl.remove(pdev);
131 
132 	return 0;
133 }
134 
135 static const struct of_device_id plat_nand_match[] = {
136 	{ .compatible = "gen_nand" },
137 	{},
138 };
139 MODULE_DEVICE_TABLE(of, plat_nand_match);
140 
141 static struct platform_driver plat_nand_driver = {
142 	.probe	= plat_nand_probe,
143 	.remove	= plat_nand_remove,
144 	.driver	= {
145 		.name		= "gen_nand",
146 		.of_match_table = plat_nand_match,
147 	},
148 };
149 
150 module_platform_driver(plat_nand_driver);
151 
152 MODULE_LICENSE("GPL");
153 MODULE_AUTHOR("Vitaly Wool");
154 MODULE_DESCRIPTION("Simple generic NAND driver");
155 MODULE_ALIAS("platform:gen_nand");
156