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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
53static void pismo_set_vpp(struct platform_device *pdev, int on)
54{
55 struct i2c_client *client = to_i2c_client(pdev->dev.parent);
56 struct pismo_data *pismo = i2c_get_clientdata(client);
57
58 pismo->vpp(pismo->vpp_data, on);
59}
60
61static unsigned int __devinit pismo_width_to_bytes(unsigned int width)
62{
63 width &= 15;
64 if (width > 2)
65 return 0;
66 return 1 << width;
67}
68
69static int __devinit pismo_eeprom_read(struct i2c_client *client, void *buf,
70 u8 addr, size_t size)
71{
72 int ret;
73 struct i2c_msg msg[] = {
74 {
75 .addr = client->addr,
76 .len = sizeof(addr),
77 .buf = &addr,
78 }, {
79 .addr = client->addr,
80 .flags = I2C_M_RD,
81 .len = size,
82 .buf = buf,
83 },
84 };
85
86 ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
87
88 return ret == ARRAY_SIZE(msg) ? size : -EIO;
89}
90
91static int __devinit pismo_add_device(struct pismo_data *pismo, int i,
92 struct pismo_mem *region, const char *name, void *pdata, size_t psize)
93{
94 struct platform_device *dev;
95 struct resource res = { };
96 phys_addr_t base = region->base;
97 int ret;
98
99 if (base == ~0)
100 return -ENXIO;
101
102 res.start = base;
103 res.end = base + region->size - 1;
104 res.flags = IORESOURCE_MEM;
105
106 dev = platform_device_alloc(name, i);
107 if (!dev)
108 return -ENOMEM;
109 dev->dev.parent = &pismo->client->dev;
110
111 do {
112 ret = platform_device_add_resources(dev, &res, 1);
113 if (ret)
114 break;
115
116 ret = platform_device_add_data(dev, pdata, psize);
117 if (ret)
118 break;
119
120 ret = platform_device_add(dev);
121 if (ret)
122 break;
123
124 pismo->dev[i] = dev;
125 return 0;
126 } while (0);
127
128 platform_device_put(dev);
129 return ret;
130}
131
132static int __devinit pismo_add_nor(struct pismo_data *pismo, int i,
133 struct pismo_mem *region)
134{
135 struct physmap_flash_data data = {
136 .width = region->width,
137 };
138
139 if (pismo->vpp)
140 data.set_vpp = pismo_set_vpp;
141
142 return pismo_add_device(pismo, i, region, "physmap-flash",
143 &data, sizeof(data));
144}
145
146static int __devinit pismo_add_sram(struct pismo_data *pismo, int i,
147 struct pismo_mem *region)
148{
149 struct platdata_mtd_ram data = {
150 .bankwidth = region->width,
151 };
152
153 return pismo_add_device(pismo, i, region, "mtd-ram",
154 &data, sizeof(data));
155}
156
157static void __devinit pismo_add_one(struct pismo_data *pismo, int i,
158 const struct pismo_cs_block *cs, phys_addr_t base)
159{
160 struct device *dev = &pismo->client->dev;
161 struct pismo_mem region;
162
163 region.base = base;
164 region.type = cs->type;
165 region.width = pismo_width_to_bytes(cs->width);
166 region.access = le16_to_cpu(cs->access);
167 region.size = le32_to_cpu(cs->size);
168
169 if (region.width == 0) {
170 dev_err(dev, "cs%u: bad width: %02x, ignoring\n", i, cs->width);
171 return;
172 }
173
174
175
176
177
178
179
180 dev_info(dev, "cs%u: %.32s: type %02x access %u00ps size %uK\n",
181 i, cs->device, region.type, region.access, region.size / 1024);
182
183 switch (region.type) {
184 case 0:
185 break;
186 case 1:
187
188 break;
189 case 2:
190
191 pismo_add_nor(pismo, i, ®ion);
192 break;
193 case 3:
194
195 pismo_add_sram(pismo, i, ®ion);
196 break;
197 }
198}
199
200static int __devexit pismo_remove(struct i2c_client *client)
201{
202 struct pismo_data *pismo = i2c_get_clientdata(client);
203 int i;
204
205 for (i = 0; i < ARRAY_SIZE(pismo->dev); i++)
206 platform_device_unregister(pismo->dev[i]);
207
208 kfree(pismo);
209
210 return 0;
211}
212
213static int __devinit pismo_probe(struct i2c_client *client,
214 const struct i2c_device_id *id)
215{
216 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
217 struct pismo_pdata *pdata = client->dev.platform_data;
218 struct pismo_eeprom eeprom;
219 struct pismo_data *pismo;
220 int ret, i;
221
222 if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) {
223 dev_err(&client->dev, "functionality mismatch\n");
224 return -EIO;
225 }
226
227 pismo = kzalloc(sizeof(*pismo), GFP_KERNEL);
228 if (!pismo)
229 return -ENOMEM;
230
231 pismo->client = client;
232 if (pdata) {
233 pismo->vpp = pdata->set_vpp;
234 pismo->vpp_data = pdata->vpp_data;
235 }
236 i2c_set_clientdata(client, pismo);
237
238 ret = pismo_eeprom_read(client, &eeprom, 0, sizeof(eeprom));
239 if (ret < 0) {
240 dev_err(&client->dev, "error reading EEPROM: %d\n", ret);
241 goto exit_free;
242 }
243
244 dev_info(&client->dev, "%.15s board found\n", eeprom.board);
245
246 for (i = 0; i < ARRAY_SIZE(eeprom.cs); i++)
247 if (eeprom.cs[i].type != 0xff)
248 pismo_add_one(pismo, i, &eeprom.cs[i],
249 pdata->cs_addrs[i]);
250
251 return 0;
252
253 exit_free:
254 kfree(pismo);
255 return ret;
256}
257
258static const struct i2c_device_id pismo_id[] = {
259 { "pismo" },
260 { },
261};
262MODULE_DEVICE_TABLE(i2c, pismo_id);
263
264static struct i2c_driver pismo_driver = {
265 .driver = {
266 .name = "pismo",
267 .owner = THIS_MODULE,
268 },
269 .probe = pismo_probe,
270 .remove = __devexit_p(pismo_remove),
271 .id_table = pismo_id,
272};
273
274static int __init pismo_init(void)
275{
276 BUILD_BUG_ON(sizeof(struct pismo_cs_block) != 48);
277 BUILD_BUG_ON(sizeof(struct pismo_eeprom) != 256);
278
279 return i2c_add_driver(&pismo_driver);
280}
281module_init(pismo_init);
282
283static void __exit pismo_exit(void)
284{
285 i2c_del_driver(&pismo_driver);
286}
287module_exit(pismo_exit);
288
289MODULE_AUTHOR("Russell King <linux@arm.linux.org.uk>");
290MODULE_DESCRIPTION("PISMO memory driver");
291MODULE_LICENSE("GPL");
292
