hyperv: Remove recv_pkt_list and lock
[linux/fpc-iii.git] / drivers / mtd / nand / socrates_nand.c
blobfe8058a4505406d33353b217c9fd8b0598f96d5a
1 /*
2 * drivers/mtd/nand/socrates_nand.c
4 * Copyright © 2008 Ilya Yanok, Emcraft Systems
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <linux/mtd/mtd.h>
16 #include <linux/mtd/nand.h>
17 #include <linux/mtd/partitions.h>
18 #include <linux/of_address.h>
19 #include <linux/of_platform.h>
20 #include <linux/io.h>
22 #define FPGA_NAND_CMD_MASK (0x7 << 28)
23 #define FPGA_NAND_CMD_COMMAND (0x0 << 28)
24 #define FPGA_NAND_CMD_ADDR (0x1 << 28)
25 #define FPGA_NAND_CMD_READ (0x2 << 28)
26 #define FPGA_NAND_CMD_WRITE (0x3 << 28)
27 #define FPGA_NAND_BUSY (0x1 << 15)
28 #define FPGA_NAND_ENABLE (0x1 << 31)
29 #define FPGA_NAND_DATA_SHIFT 16
31 struct socrates_nand_host {
32 struct nand_chip nand_chip;
33 struct mtd_info mtd;
34 void __iomem *io_base;
35 struct device *dev;
38 /**
39 * socrates_nand_write_buf - write buffer to chip
40 * @mtd: MTD device structure
41 * @buf: data buffer
42 * @len: number of bytes to write
44 static void socrates_nand_write_buf(struct mtd_info *mtd,
45 const uint8_t *buf, int len)
47 int i;
48 struct nand_chip *this = mtd->priv;
49 struct socrates_nand_host *host = this->priv;
51 for (i = 0; i < len; i++) {
52 out_be32(host->io_base, FPGA_NAND_ENABLE |
53 FPGA_NAND_CMD_WRITE |
54 (buf[i] << FPGA_NAND_DATA_SHIFT));
58 /**
59 * socrates_nand_read_buf - read chip data into buffer
60 * @mtd: MTD device structure
61 * @buf: buffer to store date
62 * @len: number of bytes to read
64 static void socrates_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
66 int i;
67 struct nand_chip *this = mtd->priv;
68 struct socrates_nand_host *host = this->priv;
69 uint32_t val;
71 val = FPGA_NAND_ENABLE | FPGA_NAND_CMD_READ;
73 out_be32(host->io_base, val);
74 for (i = 0; i < len; i++) {
75 buf[i] = (in_be32(host->io_base) >>
76 FPGA_NAND_DATA_SHIFT) & 0xff;
80 /**
81 * socrates_nand_read_byte - read one byte from the chip
82 * @mtd: MTD device structure
84 static uint8_t socrates_nand_read_byte(struct mtd_info *mtd)
86 uint8_t byte;
87 socrates_nand_read_buf(mtd, &byte, sizeof(byte));
88 return byte;
91 /**
92 * socrates_nand_read_word - read one word from the chip
93 * @mtd: MTD device structure
95 static uint16_t socrates_nand_read_word(struct mtd_info *mtd)
97 uint16_t word;
98 socrates_nand_read_buf(mtd, (uint8_t *)&word, sizeof(word));
99 return word;
103 * Hardware specific access to control-lines
105 static void socrates_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
106 unsigned int ctrl)
108 struct nand_chip *nand_chip = mtd->priv;
109 struct socrates_nand_host *host = nand_chip->priv;
110 uint32_t val;
112 if (cmd == NAND_CMD_NONE)
113 return;
115 if (ctrl & NAND_CLE)
116 val = FPGA_NAND_CMD_COMMAND;
117 else
118 val = FPGA_NAND_CMD_ADDR;
120 if (ctrl & NAND_NCE)
121 val |= FPGA_NAND_ENABLE;
123 val |= (cmd & 0xff) << FPGA_NAND_DATA_SHIFT;
125 out_be32(host->io_base, val);
129 * Read the Device Ready pin.
131 static int socrates_nand_device_ready(struct mtd_info *mtd)
133 struct nand_chip *nand_chip = mtd->priv;
134 struct socrates_nand_host *host = nand_chip->priv;
136 if (in_be32(host->io_base) & FPGA_NAND_BUSY)
137 return 0; /* busy */
138 return 1;
142 * Probe for the NAND device.
144 static int socrates_nand_probe(struct platform_device *ofdev)
146 struct socrates_nand_host *host;
147 struct mtd_info *mtd;
148 struct nand_chip *nand_chip;
149 int res;
150 struct mtd_part_parser_data ppdata;
152 /* Allocate memory for the device structure (and zero it) */
153 host = devm_kzalloc(&ofdev->dev, sizeof(*host), GFP_KERNEL);
154 if (!host)
155 return -ENOMEM;
157 host->io_base = of_iomap(ofdev->dev.of_node, 0);
158 if (host->io_base == NULL) {
159 dev_err(&ofdev->dev, "ioremap failed\n");
160 return -EIO;
163 mtd = &host->mtd;
164 nand_chip = &host->nand_chip;
165 host->dev = &ofdev->dev;
167 nand_chip->priv = host; /* link the private data structures */
168 mtd->priv = nand_chip;
169 mtd->name = "socrates_nand";
170 mtd->owner = THIS_MODULE;
171 mtd->dev.parent = &ofdev->dev;
172 ppdata.of_node = ofdev->dev.of_node;
174 /*should never be accessed directly */
175 nand_chip->IO_ADDR_R = (void *)0xdeadbeef;
176 nand_chip->IO_ADDR_W = (void *)0xdeadbeef;
178 nand_chip->cmd_ctrl = socrates_nand_cmd_ctrl;
179 nand_chip->read_byte = socrates_nand_read_byte;
180 nand_chip->read_word = socrates_nand_read_word;
181 nand_chip->write_buf = socrates_nand_write_buf;
182 nand_chip->read_buf = socrates_nand_read_buf;
183 nand_chip->dev_ready = socrates_nand_device_ready;
185 nand_chip->ecc.mode = NAND_ECC_SOFT; /* enable ECC */
187 /* TODO: I have no idea what real delay is. */
188 nand_chip->chip_delay = 20; /* 20us command delay time */
190 dev_set_drvdata(&ofdev->dev, host);
192 /* first scan to find the device and get the page size */
193 if (nand_scan_ident(mtd, 1, NULL)) {
194 res = -ENXIO;
195 goto out;
198 /* second phase scan */
199 if (nand_scan_tail(mtd)) {
200 res = -ENXIO;
201 goto out;
204 res = mtd_device_parse_register(mtd, NULL, &ppdata, NULL, 0);
205 if (!res)
206 return res;
208 nand_release(mtd);
210 out:
211 iounmap(host->io_base);
212 return res;
216 * Remove a NAND device.
218 static int socrates_nand_remove(struct platform_device *ofdev)
220 struct socrates_nand_host *host = dev_get_drvdata(&ofdev->dev);
221 struct mtd_info *mtd = &host->mtd;
223 nand_release(mtd);
225 iounmap(host->io_base);
227 return 0;
230 static const struct of_device_id socrates_nand_match[] =
233 .compatible = "abb,socrates-nand",
238 MODULE_DEVICE_TABLE(of, socrates_nand_match);
240 static struct platform_driver socrates_nand_driver = {
241 .driver = {
242 .name = "socrates_nand",
243 .owner = THIS_MODULE,
244 .of_match_table = socrates_nand_match,
246 .probe = socrates_nand_probe,
247 .remove = socrates_nand_remove,
250 module_platform_driver(socrates_nand_driver);
252 MODULE_LICENSE("GPL");
253 MODULE_AUTHOR("Ilya Yanok");
254 MODULE_DESCRIPTION("NAND driver for Socrates board");