Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs...
[linux-2.6] / drivers / mtd / nand / fsl_upm.c
1 /*
2  * Freescale UPM NAND driver.
3  *
4  * Copyright © 2007-2008  MontaVista Software, Inc.
5  *
6  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  */
13
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/delay.h>
17 #include <linux/mtd/nand.h>
18 #include <linux/mtd/nand_ecc.h>
19 #include <linux/mtd/partitions.h>
20 #include <linux/mtd/mtd.h>
21 #include <linux/of_platform.h>
22 #include <linux/of_gpio.h>
23 #include <linux/io.h>
24 #include <asm/fsl_lbc.h>
25
26 struct fsl_upm_nand {
27         struct device *dev;
28         struct mtd_info mtd;
29         struct nand_chip chip;
30         int last_ctrl;
31 #ifdef CONFIG_MTD_PARTITIONS
32         struct mtd_partition *parts;
33 #endif
34
35         struct fsl_upm upm;
36         uint8_t upm_addr_offset;
37         uint8_t upm_cmd_offset;
38         void __iomem *io_base;
39         int rnb_gpio;
40         int chip_delay;
41 };
42
43 #define to_fsl_upm_nand(mtd) container_of(mtd, struct fsl_upm_nand, mtd)
44
45 static int fun_chip_ready(struct mtd_info *mtd)
46 {
47         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
48
49         if (gpio_get_value(fun->rnb_gpio))
50                 return 1;
51
52         dev_vdbg(fun->dev, "busy\n");
53         return 0;
54 }
55
56 static void fun_wait_rnb(struct fsl_upm_nand *fun)
57 {
58         int cnt = 1000000;
59
60         if (fun->rnb_gpio >= 0) {
61                 while (--cnt && !fun_chip_ready(&fun->mtd))
62                         cpu_relax();
63                 if (!cnt)
64                         dev_err(fun->dev, "tired waiting for RNB\n");
65         } else {
66                 ndelay(100);
67         }
68 }
69
70 static void fun_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
71 {
72         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
73
74         if (!(ctrl & fun->last_ctrl)) {
75                 fsl_upm_end_pattern(&fun->upm);
76
77                 if (cmd == NAND_CMD_NONE)
78                         return;
79
80                 fun->last_ctrl = ctrl & (NAND_ALE | NAND_CLE);
81         }
82
83         if (ctrl & NAND_CTRL_CHANGE) {
84                 if (ctrl & NAND_ALE)
85                         fsl_upm_start_pattern(&fun->upm, fun->upm_addr_offset);
86                 else if (ctrl & NAND_CLE)
87                         fsl_upm_start_pattern(&fun->upm, fun->upm_cmd_offset);
88         }
89
90         fsl_upm_run_pattern(&fun->upm, fun->io_base, cmd);
91
92         fun_wait_rnb(fun);
93 }
94
95 static uint8_t fun_read_byte(struct mtd_info *mtd)
96 {
97         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
98
99         return in_8(fun->chip.IO_ADDR_R);
100 }
101
102 static void fun_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
103 {
104         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
105         int i;
106
107         for (i = 0; i < len; i++)
108                 buf[i] = in_8(fun->chip.IO_ADDR_R);
109 }
110
111 static void fun_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
112 {
113         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
114         int i;
115
116         for (i = 0; i < len; i++) {
117                 out_8(fun->chip.IO_ADDR_W, buf[i]);
118                 fun_wait_rnb(fun);
119         }
120 }
121
122 static int __devinit fun_chip_init(struct fsl_upm_nand *fun,
123                                    const struct device_node *upm_np,
124                                    const struct resource *io_res)
125 {
126         int ret;
127         struct device_node *flash_np;
128 #ifdef CONFIG_MTD_PARTITIONS
129         static const char *part_types[] = { "cmdlinepart", NULL, };
130 #endif
131
132         fun->chip.IO_ADDR_R = fun->io_base;
133         fun->chip.IO_ADDR_W = fun->io_base;
134         fun->chip.cmd_ctrl = fun_cmd_ctrl;
135         fun->chip.chip_delay = fun->chip_delay;
136         fun->chip.read_byte = fun_read_byte;
137         fun->chip.read_buf = fun_read_buf;
138         fun->chip.write_buf = fun_write_buf;
139         fun->chip.ecc.mode = NAND_ECC_SOFT;
140
141         if (fun->rnb_gpio >= 0)
142                 fun->chip.dev_ready = fun_chip_ready;
143
144         fun->mtd.priv = &fun->chip;
145         fun->mtd.owner = THIS_MODULE;
146
147         flash_np = of_get_next_child(upm_np, NULL);
148         if (!flash_np)
149                 return -ENODEV;
150
151         fun->mtd.name = kasprintf(GFP_KERNEL, "%x.%s", io_res->start,
152                                   flash_np->name);
153         if (!fun->mtd.name) {
154                 ret = -ENOMEM;
155                 goto err;
156         }
157
158         ret = nand_scan(&fun->mtd, 1);
159         if (ret)
160                 goto err;
161
162 #ifdef CONFIG_MTD_PARTITIONS
163         ret = parse_mtd_partitions(&fun->mtd, part_types, &fun->parts, 0);
164
165 #ifdef CONFIG_MTD_OF_PARTS
166         if (ret == 0) {
167                 ret = of_mtd_parse_partitions(fun->dev, flash_np, &fun->parts);
168                 if (ret < 0)
169                         goto err;
170         }
171 #endif
172         if (ret > 0)
173                 ret = add_mtd_partitions(&fun->mtd, fun->parts, ret);
174         else
175 #endif
176                 ret = add_mtd_device(&fun->mtd);
177 err:
178         of_node_put(flash_np);
179         return ret;
180 }
181
182 static int __devinit fun_probe(struct of_device *ofdev,
183                                const struct of_device_id *ofid)
184 {
185         struct fsl_upm_nand *fun;
186         struct resource io_res;
187         const uint32_t *prop;
188         int ret;
189         int size;
190
191         fun = kzalloc(sizeof(*fun), GFP_KERNEL);
192         if (!fun)
193                 return -ENOMEM;
194
195         ret = of_address_to_resource(ofdev->node, 0, &io_res);
196         if (ret) {
197                 dev_err(&ofdev->dev, "can't get IO base\n");
198                 goto err1;
199         }
200
201         ret = fsl_upm_find(io_res.start, &fun->upm);
202         if (ret) {
203                 dev_err(&ofdev->dev, "can't find UPM\n");
204                 goto err1;
205         }
206
207         prop = of_get_property(ofdev->node, "fsl,upm-addr-offset", &size);
208         if (!prop || size != sizeof(uint32_t)) {
209                 dev_err(&ofdev->dev, "can't get UPM address offset\n");
210                 ret = -EINVAL;
211                 goto err2;
212         }
213         fun->upm_addr_offset = *prop;
214
215         prop = of_get_property(ofdev->node, "fsl,upm-cmd-offset", &size);
216         if (!prop || size != sizeof(uint32_t)) {
217                 dev_err(&ofdev->dev, "can't get UPM command offset\n");
218                 ret = -EINVAL;
219                 goto err2;
220         }
221         fun->upm_cmd_offset = *prop;
222
223         fun->rnb_gpio = of_get_gpio(ofdev->node, 0);
224         if (fun->rnb_gpio >= 0) {
225                 ret = gpio_request(fun->rnb_gpio, ofdev->dev.bus_id);
226                 if (ret) {
227                         dev_err(&ofdev->dev, "can't request RNB gpio\n");
228                         goto err2;
229                 }
230                 gpio_direction_input(fun->rnb_gpio);
231         } else if (fun->rnb_gpio == -EINVAL) {
232                 dev_err(&ofdev->dev, "specified RNB gpio is invalid\n");
233                 goto err2;
234         }
235
236         prop = of_get_property(ofdev->node, "chip-delay", NULL);
237         if (prop)
238                 fun->chip_delay = *prop;
239         else
240                 fun->chip_delay = 50;
241
242         fun->io_base = devm_ioremap_nocache(&ofdev->dev, io_res.start,
243                                           io_res.end - io_res.start + 1);
244         if (!fun->io_base) {
245                 ret = -ENOMEM;
246                 goto err2;
247         }
248
249         fun->dev = &ofdev->dev;
250         fun->last_ctrl = NAND_CLE;
251
252         ret = fun_chip_init(fun, ofdev->node, &io_res);
253         if (ret)
254                 goto err2;
255
256         dev_set_drvdata(&ofdev->dev, fun);
257
258         return 0;
259 err2:
260         if (fun->rnb_gpio >= 0)
261                 gpio_free(fun->rnb_gpio);
262 err1:
263         kfree(fun);
264
265         return ret;
266 }
267
268 static int __devexit fun_remove(struct of_device *ofdev)
269 {
270         struct fsl_upm_nand *fun = dev_get_drvdata(&ofdev->dev);
271
272         nand_release(&fun->mtd);
273         kfree(fun->mtd.name);
274
275         if (fun->rnb_gpio >= 0)
276                 gpio_free(fun->rnb_gpio);
277
278         kfree(fun);
279
280         return 0;
281 }
282
283 static struct of_device_id of_fun_match[] = {
284         { .compatible = "fsl,upm-nand" },
285         {},
286 };
287 MODULE_DEVICE_TABLE(of, of_fun_match);
288
289 static struct of_platform_driver of_fun_driver = {
290         .name           = "fsl,upm-nand",
291         .match_table    = of_fun_match,
292         .probe          = fun_probe,
293         .remove         = __devexit_p(fun_remove),
294 };
295
296 static int __init fun_module_init(void)
297 {
298         return of_register_platform_driver(&of_fun_driver);
299 }
300 module_init(fun_module_init);
301
302 static void __exit fun_module_exit(void)
303 {
304         of_unregister_platform_driver(&of_fun_driver);
305 }
306 module_exit(fun_module_exit);
307
308 MODULE_LICENSE("GPL");
309 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
310 MODULE_DESCRIPTION("Driver for NAND chips working through Freescale "
311                    "LocalBus User-Programmable Machine");