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14#include <linux/bitops.h>
15#include <linux/device.h>
16#include <linux/errno.h>
17#include <linux/gpio/driver.h>
18#include <linux/io.h>
19#include <linux/ioport.h>
20#include <linux/interrupt.h>
21#include <linux/irqdesc.h>
22#include <linux/isa.h>
23#include <linux/kernel.h>
24#include <linux/module.h>
25#include <linux/moduleparam.h>
26#include <linux/spinlock.h>
27
28#define WS16C48_EXTENT 16
29#define MAX_NUM_WS16C48 max_num_isa_dev(WS16C48_EXTENT)
30
31static unsigned int base[MAX_NUM_WS16C48];
32static unsigned int num_ws16c48;
33module_param_array(base, uint, &num_ws16c48, 0);
34MODULE_PARM_DESC(base, "WinSystems WS16C48 base addresses");
35
36static unsigned int irq[MAX_NUM_WS16C48];
37module_param_array(irq, uint, NULL, 0);
38MODULE_PARM_DESC(irq, "WinSystems WS16C48 interrupt line numbers");
39
40
41
42
43
44
45
46
47
48
49
50
51struct ws16c48_gpio {
52 struct gpio_chip chip;
53 unsigned char io_state[6];
54 unsigned char out_state[6];
55 spinlock_t lock;
56 unsigned long irq_mask;
57 unsigned long flow_mask;
58 unsigned base;
59 unsigned irq;
60};
61
62static int ws16c48_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
63{
64 struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
65 const unsigned port = offset / 8;
66 const unsigned mask = BIT(offset % 8);
67
68 return !!(ws16c48gpio->io_state[port] & mask);
69}
70
71static int ws16c48_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
72{
73 struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
74 const unsigned port = offset / 8;
75 const unsigned mask = BIT(offset % 8);
76 unsigned long flags;
77
78 spin_lock_irqsave(&ws16c48gpio->lock, flags);
79
80 ws16c48gpio->io_state[port] |= mask;
81 ws16c48gpio->out_state[port] &= ~mask;
82 outb(ws16c48gpio->out_state[port], ws16c48gpio->base + port);
83
84 spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
85
86 return 0;
87}
88
89static int ws16c48_gpio_direction_output(struct gpio_chip *chip,
90 unsigned offset, int value)
91{
92 struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
93 const unsigned port = offset / 8;
94 const unsigned mask = BIT(offset % 8);
95 unsigned long flags;
96
97 spin_lock_irqsave(&ws16c48gpio->lock, flags);
98
99 ws16c48gpio->io_state[port] &= ~mask;
100 if (value)
101 ws16c48gpio->out_state[port] |= mask;
102 else
103 ws16c48gpio->out_state[port] &= ~mask;
104 outb(ws16c48gpio->out_state[port], ws16c48gpio->base + port);
105
106 spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
107
108 return 0;
109}
110
111static int ws16c48_gpio_get(struct gpio_chip *chip, unsigned offset)
112{
113 struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
114 const unsigned port = offset / 8;
115 const unsigned mask = BIT(offset % 8);
116 unsigned long flags;
117 unsigned port_state;
118
119 spin_lock_irqsave(&ws16c48gpio->lock, flags);
120
121
122 if (!(ws16c48gpio->io_state[port] & mask)) {
123 spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
124 return -EINVAL;
125 }
126
127 port_state = inb(ws16c48gpio->base + port);
128
129 spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
130
131 return !!(port_state & mask);
132}
133
134static void ws16c48_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
135{
136 struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
137 const unsigned port = offset / 8;
138 const unsigned mask = BIT(offset % 8);
139 unsigned long flags;
140
141 spin_lock_irqsave(&ws16c48gpio->lock, flags);
142
143
144 if (ws16c48gpio->io_state[port] & mask) {
145 spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
146 return;
147 }
148
149 if (value)
150 ws16c48gpio->out_state[port] |= mask;
151 else
152 ws16c48gpio->out_state[port] &= ~mask;
153 outb(ws16c48gpio->out_state[port], ws16c48gpio->base + port);
154
155 spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
156}
157
158static void ws16c48_irq_ack(struct irq_data *data)
159{
160 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
161 struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
162 const unsigned long offset = irqd_to_hwirq(data);
163 const unsigned port = offset / 8;
164 const unsigned mask = BIT(offset % 8);
165 unsigned long flags;
166 unsigned port_state;
167
168
169 if (port > 2)
170 return;
171
172 spin_lock_irqsave(&ws16c48gpio->lock, flags);
173
174 port_state = ws16c48gpio->irq_mask >> (8*port);
175
176 outb(0x80, ws16c48gpio->base + 7);
177 outb(port_state & ~mask, ws16c48gpio->base + 8 + port);
178 outb(port_state | mask, ws16c48gpio->base + 8 + port);
179 outb(0xC0, ws16c48gpio->base + 7);
180
181 spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
182}
183
184static void ws16c48_irq_mask(struct irq_data *data)
185{
186 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
187 struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
188 const unsigned long offset = irqd_to_hwirq(data);
189 const unsigned long mask = BIT(offset);
190 const unsigned port = offset / 8;
191 unsigned long flags;
192
193
194 if (port > 2)
195 return;
196
197 spin_lock_irqsave(&ws16c48gpio->lock, flags);
198
199 ws16c48gpio->irq_mask &= ~mask;
200
201 outb(0x80, ws16c48gpio->base + 7);
202 outb(ws16c48gpio->irq_mask >> (8*port), ws16c48gpio->base + 8 + port);
203 outb(0xC0, ws16c48gpio->base + 7);
204
205 spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
206}
207
208static void ws16c48_irq_unmask(struct irq_data *data)
209{
210 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
211 struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
212 const unsigned long offset = irqd_to_hwirq(data);
213 const unsigned long mask = BIT(offset);
214 const unsigned port = offset / 8;
215 unsigned long flags;
216
217
218 if (port > 2)
219 return;
220
221 spin_lock_irqsave(&ws16c48gpio->lock, flags);
222
223 ws16c48gpio->irq_mask |= mask;
224
225 outb(0x80, ws16c48gpio->base + 7);
226 outb(ws16c48gpio->irq_mask >> (8*port), ws16c48gpio->base + 8 + port);
227 outb(0xC0, ws16c48gpio->base + 7);
228
229 spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
230}
231
232static int ws16c48_irq_set_type(struct irq_data *data, unsigned flow_type)
233{
234 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
235 struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
236 const unsigned long offset = irqd_to_hwirq(data);
237 const unsigned long mask = BIT(offset);
238 const unsigned port = offset / 8;
239 unsigned long flags;
240
241
242 if (port > 2)
243 return -EINVAL;
244
245 spin_lock_irqsave(&ws16c48gpio->lock, flags);
246
247 switch (flow_type) {
248 case IRQ_TYPE_NONE:
249 break;
250 case IRQ_TYPE_EDGE_RISING:
251 ws16c48gpio->flow_mask |= mask;
252 break;
253 case IRQ_TYPE_EDGE_FALLING:
254 ws16c48gpio->flow_mask &= ~mask;
255 break;
256 default:
257 spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
258 return -EINVAL;
259 }
260
261 outb(0x40, ws16c48gpio->base + 7);
262 outb(ws16c48gpio->flow_mask >> (8*port), ws16c48gpio->base + 8 + port);
263 outb(0xC0, ws16c48gpio->base + 7);
264
265 spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
266
267 return 0;
268}
269
270static struct irq_chip ws16c48_irqchip = {
271 .name = "ws16c48",
272 .irq_ack = ws16c48_irq_ack,
273 .irq_mask = ws16c48_irq_mask,
274 .irq_unmask = ws16c48_irq_unmask,
275 .irq_set_type = ws16c48_irq_set_type
276};
277
278static irqreturn_t ws16c48_irq_handler(int irq, void *dev_id)
279{
280 struct ws16c48_gpio *const ws16c48gpio = dev_id;
281 struct gpio_chip *const chip = &ws16c48gpio->chip;
282 unsigned long int_pending;
283 unsigned long port;
284 unsigned long int_id;
285 unsigned long gpio;
286
287 int_pending = inb(ws16c48gpio->base + 6) & 0x7;
288 if (!int_pending)
289 return IRQ_NONE;
290
291
292 do {
293 for_each_set_bit(port, &int_pending, 3) {
294 int_id = inb(ws16c48gpio->base + 8 + port);
295 for_each_set_bit(gpio, &int_id, 8)
296 generic_handle_irq(irq_find_mapping(
297 chip->irqdomain, gpio + 8*port));
298 }
299
300 int_pending = inb(ws16c48gpio->base + 6) & 0x7;
301 } while (int_pending);
302
303 return IRQ_HANDLED;
304}
305
306static int ws16c48_probe(struct device *dev, unsigned int id)
307{
308 struct ws16c48_gpio *ws16c48gpio;
309 const char *const name = dev_name(dev);
310 int err;
311
312 ws16c48gpio = devm_kzalloc(dev, sizeof(*ws16c48gpio), GFP_KERNEL);
313 if (!ws16c48gpio)
314 return -ENOMEM;
315
316 if (!devm_request_region(dev, base[id], WS16C48_EXTENT, name)) {
317 dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
318 base[id], base[id] + WS16C48_EXTENT);
319 return -EBUSY;
320 }
321
322 ws16c48gpio->chip.label = name;
323 ws16c48gpio->chip.parent = dev;
324 ws16c48gpio->chip.owner = THIS_MODULE;
325 ws16c48gpio->chip.base = -1;
326 ws16c48gpio->chip.ngpio = 48;
327 ws16c48gpio->chip.get_direction = ws16c48_gpio_get_direction;
328 ws16c48gpio->chip.direction_input = ws16c48_gpio_direction_input;
329 ws16c48gpio->chip.direction_output = ws16c48_gpio_direction_output;
330 ws16c48gpio->chip.get = ws16c48_gpio_get;
331 ws16c48gpio->chip.set = ws16c48_gpio_set;
332 ws16c48gpio->base = base[id];
333 ws16c48gpio->irq = irq[id];
334
335 spin_lock_init(&ws16c48gpio->lock);
336
337 dev_set_drvdata(dev, ws16c48gpio);
338
339 err = gpiochip_add_data(&ws16c48gpio->chip, ws16c48gpio);
340 if (err) {
341 dev_err(dev, "GPIO registering failed (%d)\n", err);
342 return err;
343 }
344
345
346 outb(0x80, base[id] + 7);
347 outb(0, base[id] + 8);
348 outb(0, base[id] + 9);
349 outb(0, base[id] + 10);
350 outb(0xC0, base[id] + 7);
351
352 err = gpiochip_irqchip_add(&ws16c48gpio->chip, &ws16c48_irqchip, 0,
353 handle_edge_irq, IRQ_TYPE_NONE);
354 if (err) {
355 dev_err(dev, "Could not add irqchip (%d)\n", err);
356 goto err_gpiochip_remove;
357 }
358
359 err = request_irq(irq[id], ws16c48_irq_handler, IRQF_SHARED, name,
360 ws16c48gpio);
361 if (err) {
362 dev_err(dev, "IRQ handler registering failed (%d)\n", err);
363 goto err_gpiochip_remove;
364 }
365
366 return 0;
367
368err_gpiochip_remove:
369 gpiochip_remove(&ws16c48gpio->chip);
370 return err;
371}
372
373static int ws16c48_remove(struct device *dev, unsigned int id)
374{
375 struct ws16c48_gpio *const ws16c48gpio = dev_get_drvdata(dev);
376
377 free_irq(ws16c48gpio->irq, ws16c48gpio);
378 gpiochip_remove(&ws16c48gpio->chip);
379
380 return 0;
381}
382
383static struct isa_driver ws16c48_driver = {
384 .probe = ws16c48_probe,
385 .driver = {
386 .name = "ws16c48"
387 },
388 .remove = ws16c48_remove
389};
390
391module_isa_driver(ws16c48_driver, num_ws16c48);
392
393MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
394MODULE_DESCRIPTION("WinSystems WS16C48 GPIO driver");
395MODULE_LICENSE("GPL v2");
396
