1 /*
2 * linux/drivers/mtd/nand/cmx270-nand.c
3 *
4 * Copyright (C) 2006 Compulab, Ltd.
5 * Mike Rapoport <mike@compulab.co.il>
6 *
7 * Derived from drivers/mtd/nand/h1910.c
8 * Copyright (C) 2002 Marius Gröger (mag@sysgo.de)
9 * Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
10 *
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
15 *
16 * Overview:
17 * This is a device driver for the NAND flash device found on the
18 * CM-X270 board.
19 */
20
21 #include <linux/mtd/nand.h>
22 #include <linux/mtd/partitions.h>
23 #include <linux/slab.h>
24 #include <linux/gpio.h>
25 #include <linux/module.h>
26
27 #include <asm/io.h>
28 #include <asm/irq.h>
29 #include <asm/mach-types.h>
30
31 #include <mach/pxa2xx-regs.h>
32
33 #define GPIO_NAND_CS (11)
34 #define GPIO_NAND_RB (89)
35
36 /* MTD structure for CM-X270 board */
37 static struct mtd_info *cmx270_nand_mtd;
38
39 /* remaped IO address of the device */
40 static void __iomem *cmx270_nand_io;
41
42 /*
43 * Define static partitions for flash device
44 */
45 static struct mtd_partition partition_info[] = {
46 [0] = {
47 .name = "cmx270-0",
48 .offset = 0,
49 .size = MTDPART_SIZ_FULL
50 }
51 };
52 #define NUM_PARTITIONS (ARRAY_SIZE(partition_info))
53
cmx270_read_byte(struct mtd_info * mtd)54 static u_char cmx270_read_byte(struct mtd_info *mtd)
55 {
56 struct nand_chip *this = mtd->priv;
57
58 return (readl(this->IO_ADDR_R) >> 16);
59 }
60
cmx270_write_buf(struct mtd_info * mtd,const u_char * buf,int len)61 static void cmx270_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
62 {
63 int i;
64 struct nand_chip *this = mtd->priv;
65
66 for (i=0; i<len; i++)
67 writel((*buf++ << 16), this->IO_ADDR_W);
68 }
69
cmx270_read_buf(struct mtd_info * mtd,u_char * buf,int len)70 static void cmx270_read_buf(struct mtd_info *mtd, u_char *buf, int len)
71 {
72 int i;
73 struct nand_chip *this = mtd->priv;
74
75 for (i=0; i<len; i++)
76 *buf++ = readl(this->IO_ADDR_R) >> 16;
77 }
78
cmx270_verify_buf(struct mtd_info * mtd,const u_char * buf,int len)79 static int cmx270_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
80 {
81 int i;
82 struct nand_chip *this = mtd->priv;
83
84 for (i=0; i<len; i++)
85 if (buf[i] != (u_char)(readl(this->IO_ADDR_R) >> 16))
86 return -EFAULT;
87
88 return 0;
89 }
90
nand_cs_on(void)91 static inline void nand_cs_on(void)
92 {
93 gpio_set_value(GPIO_NAND_CS, 0);
94 }
95
nand_cs_off(void)96 static void nand_cs_off(void)
97 {
98 dsb();
99
100 gpio_set_value(GPIO_NAND_CS, 1);
101 }
102
103 /*
104 * hardware specific access to control-lines
105 */
cmx270_hwcontrol(struct mtd_info * mtd,int dat,unsigned int ctrl)106 static void cmx270_hwcontrol(struct mtd_info *mtd, int dat,
107 unsigned int ctrl)
108 {
109 struct nand_chip* this = mtd->priv;
110 unsigned int nandaddr = (unsigned int)this->IO_ADDR_W;
111
112 dsb();
113
114 if (ctrl & NAND_CTRL_CHANGE) {
115 if ( ctrl & NAND_ALE )
116 nandaddr |= (1 << 3);
117 else
118 nandaddr &= ~(1 << 3);
119 if ( ctrl & NAND_CLE )
120 nandaddr |= (1 << 2);
121 else
122 nandaddr &= ~(1 << 2);
123 if ( ctrl & NAND_NCE )
124 nand_cs_on();
125 else
126 nand_cs_off();
127 }
128
129 dsb();
130 this->IO_ADDR_W = (void __iomem*)nandaddr;
131 if (dat != NAND_CMD_NONE)
132 writel((dat << 16), this->IO_ADDR_W);
133
134 dsb();
135 }
136
137 /*
138 * read device ready pin
139 */
cmx270_device_ready(struct mtd_info * mtd)140 static int cmx270_device_ready(struct mtd_info *mtd)
141 {
142 dsb();
143
144 return (gpio_get_value(GPIO_NAND_RB));
145 }
146
147 /*
148 * Main initialization routine
149 */
cmx270_init(void)150 static int __init cmx270_init(void)
151 {
152 struct nand_chip *this;
153 int ret;
154
155 if (!(machine_is_armcore() && cpu_is_pxa27x()))
156 return -ENODEV;
157
158 ret = gpio_request(GPIO_NAND_CS, "NAND CS");
159 if (ret) {
160 pr_warning("CM-X270: failed to request NAND CS gpio\n");
161 return ret;
162 }
163
164 gpio_direction_output(GPIO_NAND_CS, 1);
165
166 ret = gpio_request(GPIO_NAND_RB, "NAND R/B");
167 if (ret) {
168 pr_warning("CM-X270: failed to request NAND R/B gpio\n");
169 goto err_gpio_request;
170 }
171
172 gpio_direction_input(GPIO_NAND_RB);
173
174 /* Allocate memory for MTD device structure and private data */
175 cmx270_nand_mtd = kzalloc(sizeof(struct mtd_info) +
176 sizeof(struct nand_chip),
177 GFP_KERNEL);
178 if (!cmx270_nand_mtd) {
179 pr_debug("Unable to allocate CM-X270 NAND MTD device structure.\n");
180 ret = -ENOMEM;
181 goto err_kzalloc;
182 }
183
184 cmx270_nand_io = ioremap(PXA_CS1_PHYS, 12);
185 if (!cmx270_nand_io) {
186 pr_debug("Unable to ioremap NAND device\n");
187 ret = -EINVAL;
188 goto err_ioremap;
189 }
190
191 /* Get pointer to private data */
192 this = (struct nand_chip *)(&cmx270_nand_mtd[1]);
193
194 /* Link the private data with the MTD structure */
195 cmx270_nand_mtd->owner = THIS_MODULE;
196 cmx270_nand_mtd->priv = this;
197
198 /* insert callbacks */
199 this->IO_ADDR_R = cmx270_nand_io;
200 this->IO_ADDR_W = cmx270_nand_io;
201 this->cmd_ctrl = cmx270_hwcontrol;
202 this->dev_ready = cmx270_device_ready;
203
204 /* 15 us command delay time */
205 this->chip_delay = 20;
206 this->ecc.mode = NAND_ECC_SOFT;
207
208 /* read/write functions */
209 this->read_byte = cmx270_read_byte;
210 this->read_buf = cmx270_read_buf;
211 this->write_buf = cmx270_write_buf;
212 this->verify_buf = cmx270_verify_buf;
213
214 /* Scan to find existence of the device */
215 if (nand_scan (cmx270_nand_mtd, 1)) {
216 pr_notice("No NAND device\n");
217 ret = -ENXIO;
218 goto err_scan;
219 }
220
221 /* Register the partitions */
222 ret = mtd_device_parse_register(cmx270_nand_mtd, NULL, 0,
223 partition_info, NUM_PARTITIONS);
224 if (ret)
225 goto err_scan;
226
227 /* Return happy */
228 return 0;
229
230 err_scan:
231 iounmap(cmx270_nand_io);
232 err_ioremap:
233 kfree(cmx270_nand_mtd);
234 err_kzalloc:
235 gpio_free(GPIO_NAND_RB);
236 err_gpio_request:
237 gpio_free(GPIO_NAND_CS);
238
239 return ret;
240
241 }
242 module_init(cmx270_init);
243
244 /*
245 * Clean up routine
246 */
cmx270_cleanup(void)247 static void __exit cmx270_cleanup(void)
248 {
249 /* Release resources, unregister device */
250 nand_release(cmx270_nand_mtd);
251
252 gpio_free(GPIO_NAND_RB);
253 gpio_free(GPIO_NAND_CS);
254
255 iounmap(cmx270_nand_io);
256
257 /* Free the MTD device structure */
258 kfree (cmx270_nand_mtd);
259 }
260 module_exit(cmx270_cleanup);
261
262 MODULE_LICENSE("GPL");
263 MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
264 MODULE_DESCRIPTION("NAND flash driver for Compulab CM-X270 Module");
265