1
2
3
4
5
6
7
8
9
10
11
12
13
14
15#define pr_fmt(fmt) "i2c-parport: " fmt
16
17#include <linux/kernel.h>
18#include <linux/module.h>
19#include <linux/init.h>
20#include <linux/delay.h>
21#include <linux/parport.h>
22#include <linux/i2c.h>
23#include <linux/i2c-algo-bit.h>
24#include <linux/i2c-smbus.h>
25#include <linux/slab.h>
26#include <linux/list.h>
27#include <linux/mutex.h>
28
29#define PORT_DATA 0
30#define PORT_STAT 1
31#define PORT_CTRL 2
32
33struct lineop {
34 u8 val;
35 u8 port;
36 u8 inverted;
37};
38
39struct adapter_parm {
40 struct lineop setsda;
41 struct lineop setscl;
42 struct lineop getsda;
43 struct lineop getscl;
44 struct lineop init;
45 unsigned int smbus_alert:1;
46};
47
48static const struct adapter_parm adapter_parm[] = {
49
50 {
51 .setsda = { 0x80, PORT_DATA, 1 },
52 .setscl = { 0x08, PORT_CTRL, 0 },
53 .getsda = { 0x80, PORT_STAT, 0 },
54 .getscl = { 0x08, PORT_STAT, 0 },
55 },
56
57 {
58 .setsda = { 0x02, PORT_DATA, 0 },
59 .setscl = { 0x01, PORT_DATA, 0 },
60 .getsda = { 0x80, PORT_STAT, 1 },
61 },
62
63 {
64 .setsda = { 0x02, PORT_CTRL, 1 },
65 .setscl = { 0x08, PORT_CTRL, 1 },
66 .getsda = { 0x10, PORT_STAT, 0 },
67 },
68
69 {
70 .setsda = { 0x02, PORT_DATA, 1 },
71 .setscl = { 0x01, PORT_DATA, 1 },
72 .getsda = { 0x40, PORT_STAT, 1 },
73 .getscl = { 0x08, PORT_STAT, 1 },
74 },
75
76 {
77 .setsda = { 0x02, PORT_DATA, 1 },
78 .setscl = { 0x01, PORT_DATA, 1 },
79 .getsda = { 0x10, PORT_STAT, 1 },
80 .init = { 0xf0, PORT_DATA, 0 },
81 .smbus_alert = 1,
82 },
83
84 {
85 .setsda = { 0x02, PORT_DATA, 1 },
86 .setscl = { 0x01, PORT_DATA, 1 },
87 .getsda = { 0x10, PORT_STAT, 1 },
88 },
89
90 {
91 .setsda = { 0x02, PORT_DATA, 1 },
92 .setscl = { 0x01, PORT_DATA, 1 },
93 .getsda = { 0x20, PORT_STAT, 0 },
94 .getscl = { 0x40, PORT_STAT, 0 },
95 .init = { 0xfc, PORT_DATA, 0 },
96 },
97
98 {
99 .setsda = { 0x01, PORT_DATA, 0 },
100 .setscl = { 0x02, PORT_DATA, 0 },
101 .getsda = { 0x80, PORT_STAT, 1 },
102 .init = { 0x04, PORT_DATA, 1 },
103 },
104
105 {
106 .setsda = { 0x04, PORT_DATA, 1 },
107 .setscl = { 0x01, PORT_DATA, 1 },
108 .getsda = { 0x40, PORT_STAT, 0 },
109 .getscl = { 0x80, PORT_STAT, 1 },
110 },
111};
112
113
114
115struct i2c_par {
116 struct pardevice *pdev;
117 struct i2c_adapter adapter;
118 struct i2c_algo_bit_data algo_data;
119 struct i2c_smbus_alert_setup alert_data;
120 struct i2c_client *ara;
121 struct list_head node;
122};
123
124static LIST_HEAD(adapter_list);
125static DEFINE_MUTEX(adapter_list_lock);
126
127#define MAX_DEVICE 4
128static int parport[MAX_DEVICE] = {0, -1, -1, -1};
129module_param_array(parport, int, NULL, 0);
130MODULE_PARM_DESC(parport,
131 "List of parallel ports to bind to, by index.\n"
132 " At most " __stringify(MAX_DEVICE) " devices are supported.\n"
133 " Default is one device connected to parport0.\n"
134);
135
136static int type = -1;
137module_param(type, int, 0);
138MODULE_PARM_DESC(type,
139 "Type of adapter:\n"
140 " 0 = Philips adapter\n"
141 " 1 = home brew teletext adapter\n"
142 " 2 = Velleman K8000 adapter\n"
143 " 3 = ELV adapter\n"
144 " 4 = ADM1032 evaluation board\n"
145 " 5 = ADM1025, ADM1030 and ADM1031 evaluation boards\n"
146 " 6 = Barco LPT->DVI (K5800236) adapter\n"
147 " 7 = One For All JP1 parallel port adapter\n"
148 " 8 = VCT-jig\n"
149);
150
151
152
153static void port_write_data(struct parport *p, unsigned char d)
154{
155 parport_write_data(p, d);
156}
157
158static void port_write_control(struct parport *p, unsigned char d)
159{
160 parport_write_control(p, d);
161}
162
163static unsigned char port_read_data(struct parport *p)
164{
165 return parport_read_data(p);
166}
167
168static unsigned char port_read_status(struct parport *p)
169{
170 return parport_read_status(p);
171}
172
173static unsigned char port_read_control(struct parport *p)
174{
175 return parport_read_control(p);
176}
177
178static void (* const port_write[])(struct parport *, unsigned char) = {
179 port_write_data,
180 NULL,
181 port_write_control,
182};
183
184static unsigned char (* const port_read[])(struct parport *) = {
185 port_read_data,
186 port_read_status,
187 port_read_control,
188};
189
190
191
192static inline void line_set(struct parport *data, int state,
193 const struct lineop *op)
194{
195 u8 oldval = port_read[op->port](data);
196
197
198 if ((op->inverted && !state) || (!op->inverted && state))
199 port_write[op->port](data, oldval | op->val);
200 else
201 port_write[op->port](data, oldval & ~op->val);
202}
203
204static inline int line_get(struct parport *data,
205 const struct lineop *op)
206{
207 u8 oldval = port_read[op->port](data);
208
209 return ((op->inverted && (oldval & op->val) != op->val)
210 || (!op->inverted && (oldval & op->val) == op->val));
211}
212
213
214
215static void parport_setscl(void *data, int state)
216{
217 line_set((struct parport *) data, state, &adapter_parm[type].setscl);
218}
219
220static void parport_setsda(void *data, int state)
221{
222 line_set((struct parport *) data, state, &adapter_parm[type].setsda);
223}
224
225static int parport_getscl(void *data)
226{
227 return line_get((struct parport *) data, &adapter_parm[type].getscl);
228}
229
230static int parport_getsda(void *data)
231{
232 return line_get((struct parport *) data, &adapter_parm[type].getsda);
233}
234
235
236
237
238
239
240static const struct i2c_algo_bit_data parport_algo_data = {
241 .setsda = parport_setsda,
242 .setscl = parport_setscl,
243 .getsda = parport_getsda,
244 .getscl = parport_getscl,
245 .udelay = 10,
246 .timeout = HZ,
247};
248
249
250
251static void i2c_parport_irq(void *data)
252{
253 struct i2c_par *adapter = data;
254 struct i2c_client *ara = adapter->ara;
255
256 if (ara) {
257 dev_dbg(&ara->dev, "SMBus alert received\n");
258 i2c_handle_smbus_alert(ara);
259 } else
260 dev_dbg(&adapter->adapter.dev,
261 "SMBus alert received but no ARA client!\n");
262}
263
264static void i2c_parport_attach(struct parport *port)
265{
266 struct i2c_par *adapter;
267 int i;
268 struct pardev_cb i2c_parport_cb;
269
270 if (type < 0) {
271 pr_warn("adapter type unspecified\n");
272 return;
273 }
274
275 if (type >= ARRAY_SIZE(adapter_parm)) {
276 pr_warn("invalid type (%d)\n", type);
277 return;
278 }
279
280 for (i = 0; i < MAX_DEVICE; i++) {
281 if (parport[i] == -1)
282 continue;
283 if (port->number == parport[i])
284 break;
285 }
286 if (i == MAX_DEVICE) {
287 pr_debug("Not using parport%d.\n", port->number);
288 return;
289 }
290
291 adapter = kzalloc(sizeof(struct i2c_par), GFP_KERNEL);
292 if (!adapter)
293 return;
294 memset(&i2c_parport_cb, 0, sizeof(i2c_parport_cb));
295 i2c_parport_cb.flags = PARPORT_FLAG_EXCL;
296 i2c_parport_cb.irq_func = i2c_parport_irq;
297 i2c_parport_cb.private = adapter;
298
299 pr_debug("attaching to %s\n", port->name);
300 parport_disable_irq(port);
301 adapter->pdev = parport_register_dev_model(port, "i2c-parport",
302 &i2c_parport_cb, i);
303 if (!adapter->pdev) {
304 pr_err("Unable to register with parport\n");
305 goto err_free;
306 }
307
308
309 adapter->adapter.owner = THIS_MODULE;
310 adapter->adapter.class = I2C_CLASS_HWMON;
311 strlcpy(adapter->adapter.name, "Parallel port adapter",
312 sizeof(adapter->adapter.name));
313 adapter->algo_data = parport_algo_data;
314
315 if (!adapter_parm[type].getscl.val) {
316 adapter->algo_data.getscl = NULL;
317 adapter->algo_data.udelay = 50;
318 }
319 adapter->algo_data.data = port;
320 adapter->adapter.algo_data = &adapter->algo_data;
321 adapter->adapter.dev.parent = port->physport->dev;
322
323 if (parport_claim_or_block(adapter->pdev) < 0) {
324 dev_err(&adapter->pdev->dev,
325 "Could not claim parallel port\n");
326 goto err_unregister;
327 }
328
329
330 parport_setsda(port, 1);
331 parport_setscl(port, 1);
332
333 if (adapter_parm[type].init.val) {
334 line_set(port, 1, &adapter_parm[type].init);
335
336 msleep(100);
337 }
338
339 if (i2c_bit_add_bus(&adapter->adapter) < 0) {
340 dev_err(&adapter->pdev->dev, "Unable to register with I2C\n");
341 goto err_unregister;
342 }
343
344
345 if (adapter_parm[type].smbus_alert) {
346 struct i2c_client *ara;
347
348 ara = i2c_new_smbus_alert_device(&adapter->adapter,
349 &adapter->alert_data);
350 if (!IS_ERR(ara)) {
351 adapter->ara = ara;
352 parport_enable_irq(port);
353 } else {
354 dev_warn(&adapter->pdev->dev,
355 "Failed to register ARA client\n");
356 }
357 }
358
359
360 mutex_lock(&adapter_list_lock);
361 list_add_tail(&adapter->node, &adapter_list);
362 mutex_unlock(&adapter_list_lock);
363 return;
364
365 err_unregister:
366 parport_release(adapter->pdev);
367 parport_unregister_device(adapter->pdev);
368 err_free:
369 kfree(adapter);
370}
371
372static void i2c_parport_detach(struct parport *port)
373{
374 struct i2c_par *adapter, *_n;
375
376
377 mutex_lock(&adapter_list_lock);
378 list_for_each_entry_safe(adapter, _n, &adapter_list, node) {
379 if (adapter->pdev->port == port) {
380 if (adapter->ara) {
381 parport_disable_irq(port);
382 i2c_unregister_device(adapter->ara);
383 }
384 i2c_del_adapter(&adapter->adapter);
385
386
387 if (adapter_parm[type].init.val)
388 line_set(port, 0, &adapter_parm[type].init);
389
390 parport_release(adapter->pdev);
391 parport_unregister_device(adapter->pdev);
392 list_del(&adapter->node);
393 kfree(adapter);
394 }
395 }
396 mutex_unlock(&adapter_list_lock);
397}
398
399static struct parport_driver i2c_parport_driver = {
400 .name = "i2c-parport",
401 .match_port = i2c_parport_attach,
402 .detach = i2c_parport_detach,
403 .devmodel = true,
404};
405module_parport_driver(i2c_parport_driver);
406
407MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
408MODULE_DESCRIPTION("I2C bus over parallel port");
409MODULE_LICENSE("GPL");
410
