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
nand_cs_on(void)79 static inline void nand_cs_on(void)
80 {
81 gpio_set_value(GPIO_NAND_CS, 0);
82 }
83
nand_cs_off(void)84 static void nand_cs_off(void)
85 {
86 dsb();
87
88 gpio_set_value(GPIO_NAND_CS, 1);
89 }
90
91 /*
92 * hardware specific access to control-lines
93 */
cmx270_hwcontrol(struct mtd_info * mtd,int dat,unsigned int ctrl)94 static void cmx270_hwcontrol(struct mtd_info *mtd, int dat,
95 unsigned int ctrl)
96 {
97 struct nand_chip* this = mtd->priv;
98 unsigned int nandaddr = (unsigned int)this->IO_ADDR_W;
99
100 dsb();
101
102 if (ctrl & NAND_CTRL_CHANGE) {
103 if ( ctrl & NAND_ALE )
104 nandaddr |= (1 << 3);
105 else
106 nandaddr &= ~(1 << 3);
107 if ( ctrl & NAND_CLE )
108 nandaddr |= (1 << 2);
109 else
110 nandaddr &= ~(1 << 2);
111 if ( ctrl & NAND_NCE )
112 nand_cs_on();
113 else
114 nand_cs_off();
115 }
116
117 dsb();
118 this->IO_ADDR_W = (void __iomem*)nandaddr;
119 if (dat != NAND_CMD_NONE)
120 writel((dat << 16), this->IO_ADDR_W);
121
122 dsb();
123 }
124
125 /*
126 * read device ready pin
127 */
cmx270_device_ready(struct mtd_info * mtd)128 static int cmx270_device_ready(struct mtd_info *mtd)
129 {
130 dsb();
131
132 return (gpio_get_value(GPIO_NAND_RB));
133 }
134
135 /*
136 * Main initialization routine
137 */
cmx270_init(void)138 static int __init cmx270_init(void)
139 {
140 struct nand_chip *this;
141 int ret;
142
143 if (!(machine_is_armcore() && cpu_is_pxa27x()))
144 return -ENODEV;
145
146 ret = gpio_request(GPIO_NAND_CS, "NAND CS");
147 if (ret) {
148 pr_warning("CM-X270: failed to request NAND CS gpio\n");
149 return ret;
150 }
151
152 gpio_direction_output(GPIO_NAND_CS, 1);
153
154 ret = gpio_request(GPIO_NAND_RB, "NAND R/B");
155 if (ret) {
156 pr_warning("CM-X270: failed to request NAND R/B gpio\n");
157 goto err_gpio_request;
158 }
159
160 gpio_direction_input(GPIO_NAND_RB);
161
162 /* Allocate memory for MTD device structure and private data */
163 cmx270_nand_mtd = kzalloc(sizeof(struct mtd_info) +
164 sizeof(struct nand_chip),
165 GFP_KERNEL);
166 if (!cmx270_nand_mtd) {
167 pr_debug("Unable to allocate CM-X270 NAND MTD device structure.\n");
168 ret = -ENOMEM;
169 goto err_kzalloc;
170 }
171
172 cmx270_nand_io = ioremap(PXA_CS1_PHYS, 12);
173 if (!cmx270_nand_io) {
174 pr_debug("Unable to ioremap NAND device\n");
175 ret = -EINVAL;
176 goto err_ioremap;
177 }
178
179 /* Get pointer to private data */
180 this = (struct nand_chip *)(&cmx270_nand_mtd[1]);
181
182 /* Link the private data with the MTD structure */
183 cmx270_nand_mtd->owner = THIS_MODULE;
184 cmx270_nand_mtd->priv = this;
185
186 /* insert callbacks */
187 this->IO_ADDR_R = cmx270_nand_io;
188 this->IO_ADDR_W = cmx270_nand_io;
189 this->cmd_ctrl = cmx270_hwcontrol;
190 this->dev_ready = cmx270_device_ready;
191
192 /* 15 us command delay time */
193 this->chip_delay = 20;
194 this->ecc.mode = NAND_ECC_SOFT;
195
196 /* read/write functions */
197 this->read_byte = cmx270_read_byte;
198 this->read_buf = cmx270_read_buf;
199 this->write_buf = cmx270_write_buf;
200
201 /* Scan to find existence of the device */
202 if (nand_scan (cmx270_nand_mtd, 1)) {
203 pr_notice("No NAND device\n");
204 ret = -ENXIO;
205 goto err_scan;
206 }
207
208 /* Register the partitions */
209 ret = mtd_device_parse_register(cmx270_nand_mtd, NULL, NULL,
210 partition_info, NUM_PARTITIONS);
211 if (ret)
212 goto err_scan;
213
214 /* Return happy */
215 return 0;
216
217 err_scan:
218 iounmap(cmx270_nand_io);
219 err_ioremap:
220 kfree(cmx270_nand_mtd);
221 err_kzalloc:
222 gpio_free(GPIO_NAND_RB);
223 err_gpio_request:
224 gpio_free(GPIO_NAND_CS);
225
226 return ret;
227
228 }
229 module_init(cmx270_init);
230
231 /*
232 * Clean up routine
233 */
cmx270_cleanup(void)234 static void __exit cmx270_cleanup(void)
235 {
236 /* Release resources, unregister device */
237 nand_release(cmx270_nand_mtd);
238
239 gpio_free(GPIO_NAND_RB);
240 gpio_free(GPIO_NAND_CS);
241
242 iounmap(cmx270_nand_io);
243
244 /* Free the MTD device structure */
245 kfree (cmx270_nand_mtd);
246 }
247 module_exit(cmx270_cleanup);
248
249 MODULE_LICENSE("GPL");
250 MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
251 MODULE_DESCRIPTION("NAND flash driver for Compulab CM-X270 Module");
252