1
2
3
4
5
6
7
8
9
10#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/i2c.h>
13#include <linux/slab.h>
14#include <linux/platform_device.h>
15#include <linux/spinlock.h>
16#include <linux/mutex.h>
17#include <linux/mtd/physmap.h>
18#include <linux/mtd/plat-ram.h>
19#include <linux/mtd/pismo.h>
20
21#define PISMO_NUM_CS 5
22
23struct pismo_cs_block {
24 u8 type;
25 u8 width;
26 __le16 access;
27 __le32 size;
28 u32 reserved[2];
29 char device[32];
30} __packed;
31
32struct pismo_eeprom {
33 struct pismo_cs_block cs[PISMO_NUM_CS];
34 char board[15];
35 u8 sum;
36} __packed;
37
38struct pismo_mem {
39 phys_addr_t base;
40 u32 size;
41 u16 access;
42 u8 width;
43 u8 type;
44};
45
46struct pismo_data {
47 struct i2c_client *client;
48 void (*vpp)(void *, int);
49 void *vpp_data;
50 struct platform_device *dev[PISMO_NUM_CS];
51};
52
53
54static struct pismo_data *vpp_pismo;
55static DEFINE_MUTEX(pismo_mutex);
56
57static int pismo_setvpp_probe_fix(struct pismo_data *pismo)
58{
59 mutex_lock(&pismo_mutex);
60 if (vpp_pismo) {
61 mutex_unlock(&pismo_mutex);
62 kfree(pismo);
63 return -EBUSY;
64 }
65 vpp_pismo = pismo;
66 mutex_unlock(&pismo_mutex);
67 return 0;
68}
69
70static void pismo_setvpp_remove_fix(struct pismo_data *pismo)
71{
72 mutex_lock(&pismo_mutex);
73 if (vpp_pismo == pismo)
74 vpp_pismo = NULL;
75 mutex_unlock(&pismo_mutex);
76}
77
78static void pismo_set_vpp(struct map_info *map, int on)
79{
80 struct pismo_data *pismo = vpp_pismo;
81
82 pismo->vpp(pismo->vpp_data, on);
83}
84
85
86
87static unsigned int __devinit pismo_width_to_bytes(unsigned int width)
88{
89 width &= 15;
90 if (width > 2)
91 return 0;
92 return 1 << width;
93}
94
95static int __devinit pismo_eeprom_read(struct i2c_client *client, void *buf,
96 u8 addr, size_t size)
97{
98 int ret;
99 struct i2c_msg msg[] = {
100 {
101 .addr = client->addr,
102 .len = sizeof(addr),
103 .buf = &addr,
104 }, {
105 .addr = client->addr,
106 .flags = I2C_M_RD,
107 .len = size,
108 .buf = buf,
109 },
110 };
111
112 ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
113
114 return ret == ARRAY_SIZE(msg) ? size : -EIO;
115}
116
117static int __devinit pismo_add_device(struct pismo_data *pismo, int i,
118 struct pismo_mem *region, const char *name, void *pdata, size_t psize)
119{
120 struct platform_device *dev;
121 struct resource res = { };
122 phys_addr_t base = region->base;
123 int ret;
124
125 if (base == ~0)
126 return -ENXIO;
127
128 res.start = base;
129 res.end = base + region->size - 1;
130 res.flags = IORESOURCE_MEM;
131
132 dev = platform_device_alloc(name, i);
133 if (!dev)
134 return -ENOMEM;
135 dev->dev.parent = &pismo->client->dev;
136
137 do {
138 ret = platform_device_add_resources(dev, &res, 1);
139 if (ret)
140 break;
141
142 ret = platform_device_add_data(dev, pdata, psize);
143 if (ret)
144 break;
145
146 ret = platform_device_add(dev);
147 if (ret)
148 break;
149
150 pismo->dev[i] = dev;
151 return 0;
152 } while (0);
153
154 platform_device_put(dev);
155 return ret;
156}
157
158static int __devinit pismo_add_nor(struct pismo_data *pismo, int i,
159 struct pismo_mem *region)
160{
161 struct physmap_flash_data data = {
162 .width = region->width,
163 };
164
165 if (pismo->vpp)
166 data.set_vpp = pismo_set_vpp;
167
168 return pismo_add_device(pismo, i, region, "physmap-flash",
169 &data, sizeof(data));
170}
171
172static int __devinit pismo_add_sram(struct pismo_data *pismo, int i,
173 struct pismo_mem *region)
174{
175 struct platdata_mtd_ram data = {
176 .bankwidth = region->width,
177 };
178
179 return pismo_add_device(pismo, i, region, "mtd-ram",
180 &data, sizeof(data));
181}
182
183static void __devinit pismo_add_one(struct pismo_data *pismo, int i,
184 const struct pismo_cs_block *cs, phys_addr_t base)
185{
186 struct device *dev = &pismo->client->dev;
187 struct pismo_mem region;
188
189 region.base = base;
190 region.type = cs->type;
191 region.width = pismo_width_to_bytes(cs->width);
192 region.access = le16_to_cpu(cs->access);
193 region.size = le32_to_cpu(cs->size);
194
195 if (region.width == 0) {
196 dev_err(dev, "cs%u: bad width: %02x, ignoring\n", i, cs->width);
197 return;
198 }
199
200
201
202
203
204
205
206 dev_info(dev, "cs%u: %.32s: type %02x access %u00ps size %uK\n",
207 i, cs->device, region.type, region.access, region.size / 1024);
208
209 switch (region.type) {
210 case 0:
211 break;
212 case 1:
213
214 break;
215 case 2:
216
217 pismo_add_nor(pismo, i, ®ion);
218 break;
219 case 3:
220
221 pismo_add_sram(pismo, i, ®ion);
222 break;
223 }
224}
225
226static int __devexit pismo_remove(struct i2c_client *client)
227{
228 struct pismo_data *pismo = i2c_get_clientdata(client);
229 int i;
230
231 for (i = 0; i < ARRAY_SIZE(pismo->dev); i++)
232 platform_device_unregister(pismo->dev[i]);
233
234
235 pismo_setvpp_remove_fix(pismo);
236
237 kfree(pismo);
238
239 return 0;
240}
241
242static int __devinit pismo_probe(struct i2c_client *client,
243 const struct i2c_device_id *id)
244{
245 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
246 struct pismo_pdata *pdata = client->dev.platform_data;
247 struct pismo_eeprom eeprom;
248 struct pismo_data *pismo;
249 int ret, i;
250
251 if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) {
252 dev_err(&client->dev, "functionality mismatch\n");
253 return -EIO;
254 }
255
256 pismo = kzalloc(sizeof(*pismo), GFP_KERNEL);
257 if (!pismo)
258 return -ENOMEM;
259
260
261 ret = pismo_setvpp_probe_fix(pismo);
262 if (ret)
263 return ret;
264
265 pismo->client = client;
266 if (pdata) {
267 pismo->vpp = pdata->set_vpp;
268 pismo->vpp_data = pdata->vpp_data;
269 }
270 i2c_set_clientdata(client, pismo);
271
272 ret = pismo_eeprom_read(client, &eeprom, 0, sizeof(eeprom));
273 if (ret < 0) {
274 dev_err(&client->dev, "error reading EEPROM: %d\n", ret);
275 goto exit_free;
276 }
277
278 dev_info(&client->dev, "%.15s board found\n", eeprom.board);
279
280 for (i = 0; i < ARRAY_SIZE(eeprom.cs); i++)
281 if (eeprom.cs[i].type != 0xff)
282 pismo_add_one(pismo, i, &eeprom.cs[i],
283 pdata->cs_addrs[i]);
284
285 return 0;
286
287 exit_free:
288 kfree(pismo);
289 return ret;
290}
291
292static const struct i2c_device_id pismo_id[] = {
293 { "pismo" },
294 { },
295};
296MODULE_DEVICE_TABLE(i2c, pismo_id);
297
298static struct i2c_driver pismo_driver = {
299 .driver = {
300 .name = "pismo",
301 .owner = THIS_MODULE,
302 },
303 .probe = pismo_probe,
304 .remove = __devexit_p(pismo_remove),
305 .id_table = pismo_id,
306};
307
308static int __init pismo_init(void)
309{
310 BUILD_BUG_ON(sizeof(struct pismo_cs_block) != 48);
311 BUILD_BUG_ON(sizeof(struct pismo_eeprom) != 256);
312
313 return i2c_add_driver(&pismo_driver);
314}
315module_init(pismo_init);
316
317static void __exit pismo_exit(void)
318{
319 i2c_del_driver(&pismo_driver);
320}
321module_exit(pismo_exit);
322
323MODULE_AUTHOR("Russell King <linux@arm.linux.org.uk>");
324MODULE_DESCRIPTION("PISMO memory driver");
325MODULE_LICENSE("GPL");
326
