Linux-libre 3.2.72-gnu1
[librecmc/linux-libre.git] / 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 <linux/slab.h>
25 #include <asm/fsl_lbc.h>
26
27 #define FSL_UPM_WAIT_RUN_PATTERN  0x1
28 #define FSL_UPM_WAIT_WRITE_BYTE   0x2
29 #define FSL_UPM_WAIT_WRITE_BUFFER 0x4
30
31 struct fsl_upm_nand {
32         struct device *dev;
33         struct mtd_info mtd;
34         struct nand_chip chip;
35         int last_ctrl;
36         struct mtd_partition *parts;
37         struct fsl_upm upm;
38         uint8_t upm_addr_offset;
39         uint8_t upm_cmd_offset;
40         void __iomem *io_base;
41         int rnb_gpio[NAND_MAX_CHIPS];
42         uint32_t mchip_offsets[NAND_MAX_CHIPS];
43         uint32_t mchip_count;
44         uint32_t mchip_number;
45         int chip_delay;
46         uint32_t wait_flags;
47 };
48
49 static inline struct fsl_upm_nand *to_fsl_upm_nand(struct mtd_info *mtdinfo)
50 {
51         return container_of(mtdinfo, struct fsl_upm_nand, mtd);
52 }
53
54 static int fun_chip_ready(struct mtd_info *mtd)
55 {
56         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
57
58         if (gpio_get_value(fun->rnb_gpio[fun->mchip_number]))
59                 return 1;
60
61         dev_vdbg(fun->dev, "busy\n");
62         return 0;
63 }
64
65 static void fun_wait_rnb(struct fsl_upm_nand *fun)
66 {
67         if (fun->rnb_gpio[fun->mchip_number] >= 0) {
68                 int cnt = 1000000;
69
70                 while (--cnt && !fun_chip_ready(&fun->mtd))
71                         cpu_relax();
72                 if (!cnt)
73                         dev_err(fun->dev, "tired waiting for RNB\n");
74         } else {
75                 ndelay(100);
76         }
77 }
78
79 static void fun_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
80 {
81         struct nand_chip *chip = mtd->priv;
82         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
83         u32 mar;
84
85         if (!(ctrl & fun->last_ctrl)) {
86                 fsl_upm_end_pattern(&fun->upm);
87
88                 if (cmd == NAND_CMD_NONE)
89                         return;
90
91                 fun->last_ctrl = ctrl & (NAND_ALE | NAND_CLE);
92         }
93
94         if (ctrl & NAND_CTRL_CHANGE) {
95                 if (ctrl & NAND_ALE)
96                         fsl_upm_start_pattern(&fun->upm, fun->upm_addr_offset);
97                 else if (ctrl & NAND_CLE)
98                         fsl_upm_start_pattern(&fun->upm, fun->upm_cmd_offset);
99         }
100
101         mar = (cmd << (32 - fun->upm.width)) |
102                 fun->mchip_offsets[fun->mchip_number];
103         fsl_upm_run_pattern(&fun->upm, chip->IO_ADDR_R, mar);
104
105         if (fun->wait_flags & FSL_UPM_WAIT_RUN_PATTERN)
106                 fun_wait_rnb(fun);
107 }
108
109 static void fun_select_chip(struct mtd_info *mtd, int mchip_nr)
110 {
111         struct nand_chip *chip = mtd->priv;
112         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
113
114         if (mchip_nr == -1) {
115                 chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
116         } else if (mchip_nr >= 0 && mchip_nr < NAND_MAX_CHIPS) {
117                 fun->mchip_number = mchip_nr;
118                 chip->IO_ADDR_R = fun->io_base + fun->mchip_offsets[mchip_nr];
119                 chip->IO_ADDR_W = chip->IO_ADDR_R;
120         } else {
121                 BUG();
122         }
123 }
124
125 static uint8_t fun_read_byte(struct mtd_info *mtd)
126 {
127         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
128
129         return in_8(fun->chip.IO_ADDR_R);
130 }
131
132 static void fun_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
133 {
134         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
135         int i;
136
137         for (i = 0; i < len; i++)
138                 buf[i] = in_8(fun->chip.IO_ADDR_R);
139 }
140
141 static void fun_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
142 {
143         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
144         int i;
145
146         for (i = 0; i < len; i++) {
147                 out_8(fun->chip.IO_ADDR_W, buf[i]);
148                 if (fun->wait_flags & FSL_UPM_WAIT_WRITE_BYTE)
149                         fun_wait_rnb(fun);
150         }
151         if (fun->wait_flags & FSL_UPM_WAIT_WRITE_BUFFER)
152                 fun_wait_rnb(fun);
153 }
154
155 static int __devinit fun_chip_init(struct fsl_upm_nand *fun,
156                                    const struct device_node *upm_np,
157                                    const struct resource *io_res)
158 {
159         int ret;
160         struct device_node *flash_np;
161         struct mtd_part_parser_data ppdata;
162
163         fun->chip.IO_ADDR_R = fun->io_base;
164         fun->chip.IO_ADDR_W = fun->io_base;
165         fun->chip.cmd_ctrl = fun_cmd_ctrl;
166         fun->chip.chip_delay = fun->chip_delay;
167         fun->chip.read_byte = fun_read_byte;
168         fun->chip.read_buf = fun_read_buf;
169         fun->chip.write_buf = fun_write_buf;
170         fun->chip.ecc.mode = NAND_ECC_SOFT;
171         if (fun->mchip_count > 1)
172                 fun->chip.select_chip = fun_select_chip;
173
174         if (fun->rnb_gpio[0] >= 0)
175                 fun->chip.dev_ready = fun_chip_ready;
176
177         fun->mtd.priv = &fun->chip;
178         fun->mtd.owner = THIS_MODULE;
179
180         flash_np = of_get_next_child(upm_np, NULL);
181         if (!flash_np)
182                 return -ENODEV;
183
184         fun->mtd.name = kasprintf(GFP_KERNEL, "0x%llx.%s", (u64)io_res->start,
185                                   flash_np->name);
186         if (!fun->mtd.name) {
187                 ret = -ENOMEM;
188                 goto err;
189         }
190
191         ret = nand_scan(&fun->mtd, fun->mchip_count);
192         if (ret)
193                 goto err;
194
195         ppdata.of_node = flash_np;
196         ret = mtd_device_parse_register(&fun->mtd, NULL, &ppdata, NULL, 0);
197 err:
198         of_node_put(flash_np);
199         if (ret)
200                 kfree(fun->mtd.name);
201         return ret;
202 }
203
204 static int __devinit fun_probe(struct platform_device *ofdev)
205 {
206         struct fsl_upm_nand *fun;
207         struct resource io_res;
208         const __be32 *prop;
209         int rnb_gpio;
210         int ret;
211         int size;
212         int i;
213
214         fun = kzalloc(sizeof(*fun), GFP_KERNEL);
215         if (!fun)
216                 return -ENOMEM;
217
218         ret = of_address_to_resource(ofdev->dev.of_node, 0, &io_res);
219         if (ret) {
220                 dev_err(&ofdev->dev, "can't get IO base\n");
221                 goto err1;
222         }
223
224         ret = fsl_upm_find(io_res.start, &fun->upm);
225         if (ret) {
226                 dev_err(&ofdev->dev, "can't find UPM\n");
227                 goto err1;
228         }
229
230         prop = of_get_property(ofdev->dev.of_node, "fsl,upm-addr-offset",
231                                &size);
232         if (!prop || size != sizeof(uint32_t)) {
233                 dev_err(&ofdev->dev, "can't get UPM address offset\n");
234                 ret = -EINVAL;
235                 goto err1;
236         }
237         fun->upm_addr_offset = *prop;
238
239         prop = of_get_property(ofdev->dev.of_node, "fsl,upm-cmd-offset", &size);
240         if (!prop || size != sizeof(uint32_t)) {
241                 dev_err(&ofdev->dev, "can't get UPM command offset\n");
242                 ret = -EINVAL;
243                 goto err1;
244         }
245         fun->upm_cmd_offset = *prop;
246
247         prop = of_get_property(ofdev->dev.of_node,
248                                "fsl,upm-addr-line-cs-offsets", &size);
249         if (prop && (size / sizeof(uint32_t)) > 0) {
250                 fun->mchip_count = size / sizeof(uint32_t);
251                 if (fun->mchip_count >= NAND_MAX_CHIPS) {
252                         dev_err(&ofdev->dev, "too much multiple chips\n");
253                         goto err1;
254                 }
255                 for (i = 0; i < fun->mchip_count; i++)
256                         fun->mchip_offsets[i] = be32_to_cpu(prop[i]);
257         } else {
258                 fun->mchip_count = 1;
259         }
260
261         for (i = 0; i < fun->mchip_count; i++) {
262                 fun->rnb_gpio[i] = -1;
263                 rnb_gpio = of_get_gpio(ofdev->dev.of_node, i);
264                 if (rnb_gpio >= 0) {
265                         ret = gpio_request(rnb_gpio, dev_name(&ofdev->dev));
266                         if (ret) {
267                                 dev_err(&ofdev->dev,
268                                         "can't request RNB gpio #%d\n", i);
269                                 goto err2;
270                         }
271                         gpio_direction_input(rnb_gpio);
272                         fun->rnb_gpio[i] = rnb_gpio;
273                 } else if (rnb_gpio == -EINVAL) {
274                         dev_err(&ofdev->dev, "RNB gpio #%d is invalid\n", i);
275                         goto err2;
276                 }
277         }
278
279         prop = of_get_property(ofdev->dev.of_node, "chip-delay", NULL);
280         if (prop)
281                 fun->chip_delay = be32_to_cpup(prop);
282         else
283                 fun->chip_delay = 50;
284
285         prop = of_get_property(ofdev->dev.of_node, "fsl,upm-wait-flags", &size);
286         if (prop && size == sizeof(uint32_t))
287                 fun->wait_flags = be32_to_cpup(prop);
288         else
289                 fun->wait_flags = FSL_UPM_WAIT_RUN_PATTERN |
290                                   FSL_UPM_WAIT_WRITE_BYTE;
291
292         fun->io_base = devm_ioremap_nocache(&ofdev->dev, io_res.start,
293                                             resource_size(&io_res));
294         if (!fun->io_base) {
295                 ret = -ENOMEM;
296                 goto err2;
297         }
298
299         fun->dev = &ofdev->dev;
300         fun->last_ctrl = NAND_CLE;
301
302         ret = fun_chip_init(fun, ofdev->dev.of_node, &io_res);
303         if (ret)
304                 goto err2;
305
306         dev_set_drvdata(&ofdev->dev, fun);
307
308         return 0;
309 err2:
310         for (i = 0; i < fun->mchip_count; i++) {
311                 if (fun->rnb_gpio[i] < 0)
312                         break;
313                 gpio_free(fun->rnb_gpio[i]);
314         }
315 err1:
316         kfree(fun);
317
318         return ret;
319 }
320
321 static int __devexit fun_remove(struct platform_device *ofdev)
322 {
323         struct fsl_upm_nand *fun = dev_get_drvdata(&ofdev->dev);
324         int i;
325
326         nand_release(&fun->mtd);
327         kfree(fun->mtd.name);
328
329         for (i = 0; i < fun->mchip_count; i++) {
330                 if (fun->rnb_gpio[i] < 0)
331                         break;
332                 gpio_free(fun->rnb_gpio[i]);
333         }
334
335         kfree(fun);
336
337         return 0;
338 }
339
340 static const struct of_device_id of_fun_match[] = {
341         { .compatible = "fsl,upm-nand" },
342         {},
343 };
344 MODULE_DEVICE_TABLE(of, of_fun_match);
345
346 static struct platform_driver of_fun_driver = {
347         .driver = {
348                 .name = "fsl,upm-nand",
349                 .owner = THIS_MODULE,
350                 .of_match_table = of_fun_match,
351         },
352         .probe          = fun_probe,
353         .remove         = __devexit_p(fun_remove),
354 };
355
356 static int __init fun_module_init(void)
357 {
358         return platform_driver_register(&of_fun_driver);
359 }
360 module_init(fun_module_init);
361
362 static void __exit fun_module_exit(void)
363 {
364         platform_driver_unregister(&of_fun_driver);
365 }
366 module_exit(fun_module_exit);
367
368 MODULE_LICENSE("GPL");
369 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
370 MODULE_DESCRIPTION("Driver for NAND chips working through Freescale "
371                    "LocalBus User-Programmable Machine");