blob: d3e74f8585e0b087507c47618bc344d751c8800c [file] [log] [blame]
Philipp Zabela1635b82008-04-09 19:20:34 +01001/*
2 * Support for the GPIO/IRQ expander chips present on several HTC phones.
3 * These are implemented in CPLD chips present on the board.
4 *
5 * Copyright (c) 2007 Kevin O'Connor <kevin@koconnor.net>
6 * Copyright (c) 2007 Philipp Zabel <philipp.zabel@gmail.com>
7 *
8 * This file may be distributed under the terms of the GNU GPL license.
9 */
10
11#include <linux/kernel.h>
12#include <linux/errno.h>
13#include <linux/interrupt.h>
14#include <linux/irq.h>
15#include <linux/io.h>
16#include <linux/spinlock.h>
17#include <linux/platform_device.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090018#include <linux/slab.h>
Philipp Zabela1635b82008-04-09 19:20:34 +010019#include <linux/module.h>
20#include <linux/mfd/htc-egpio.h>
21
22struct egpio_chip {
23 int reg_start;
24 int cached_values;
25 unsigned long is_out;
26 struct device *dev;
27 struct gpio_chip chip;
28};
29
30struct egpio_info {
31 spinlock_t lock;
32
33 /* iomem info */
34 void __iomem *base_addr;
35 int bus_shift; /* byte shift */
36 int reg_shift; /* bit shift */
37 int reg_mask;
38
39 /* irq info */
40 int ack_register;
41 int ack_write;
42 u16 irqs_enabled;
43 uint irq_start;
44 int nirqs;
45 uint chained_irq;
46
47 /* egpio info */
48 struct egpio_chip *chip;
49 int nchips;
50};
51
52static inline void egpio_writew(u16 value, struct egpio_info *ei, int reg)
53{
54 writew(value, ei->base_addr + (reg << ei->bus_shift));
55}
56
57static inline u16 egpio_readw(struct egpio_info *ei, int reg)
58{
59 return readw(ei->base_addr + (reg << ei->bus_shift));
60}
61
62/*
63 * IRQs
64 */
65
66static inline void ack_irqs(struct egpio_info *ei)
67{
68 egpio_writew(ei->ack_write, ei, ei->ack_register);
69 pr_debug("EGPIO ack - write %x to base+%x\n",
70 ei->ack_write, ei->ack_register << ei->bus_shift);
71}
72
73static void egpio_ack(unsigned int irq)
74{
75}
76
77/* There does not appear to be a way to proactively mask interrupts
78 * on the egpio chip itself. So, we simply ignore interrupts that
79 * aren't desired. */
80static void egpio_mask(unsigned int irq)
81{
82 struct egpio_info *ei = get_irq_chip_data(irq);
83 ei->irqs_enabled &= ~(1 << (irq - ei->irq_start));
84 pr_debug("EGPIO mask %d %04x\n", irq, ei->irqs_enabled);
85}
86static void egpio_unmask(unsigned int irq)
87{
88 struct egpio_info *ei = get_irq_chip_data(irq);
89 ei->irqs_enabled |= 1 << (irq - ei->irq_start);
90 pr_debug("EGPIO unmask %d %04x\n", irq, ei->irqs_enabled);
91}
92
93static struct irq_chip egpio_muxed_chip = {
94 .name = "htc-egpio",
95 .ack = egpio_ack,
96 .mask = egpio_mask,
97 .unmask = egpio_unmask,
98};
99
100static void egpio_handler(unsigned int irq, struct irq_desc *desc)
101{
102 struct egpio_info *ei = get_irq_data(irq);
103 int irqpin;
104
105 /* Read current pins. */
106 unsigned long readval = egpio_readw(ei, ei->ack_register);
107 pr_debug("IRQ reg: %x\n", (unsigned int)readval);
108 /* Ack/unmask interrupts. */
109 ack_irqs(ei);
110 /* Process all set pins. */
111 readval &= ei->irqs_enabled;
Akinobu Mita984b3f52010-03-05 13:41:37 -0800112 for_each_set_bit(irqpin, &readval, ei->nirqs) {
Philipp Zabela1635b82008-04-09 19:20:34 +0100113 /* Run irq handler */
114 pr_debug("got IRQ %d\n", irqpin);
115 irq = ei->irq_start + irqpin;
Yinghai Lu08678b02008-08-19 20:50:05 -0700116 desc = irq_to_desc(irq);
Philipp Zabela1635b82008-04-09 19:20:34 +0100117 desc->handle_irq(irq, desc);
118 }
119}
120
121int htc_egpio_get_wakeup_irq(struct device *dev)
122{
123 struct egpio_info *ei = dev_get_drvdata(dev);
124
125 /* Read current pins. */
126 u16 readval = egpio_readw(ei, ei->ack_register);
127 /* Ack/unmask interrupts. */
128 ack_irqs(ei);
129 /* Return first set pin. */
130 readval &= ei->irqs_enabled;
131 return ei->irq_start + ffs(readval) - 1;
132}
133EXPORT_SYMBOL(htc_egpio_get_wakeup_irq);
134
135static inline int egpio_pos(struct egpio_info *ei, int bit)
136{
137 return bit >> ei->reg_shift;
138}
139
140static inline int egpio_bit(struct egpio_info *ei, int bit)
141{
142 return 1 << (bit & ((1 << ei->reg_shift)-1));
143}
144
145/*
146 * Input pins
147 */
148
149static int egpio_get(struct gpio_chip *chip, unsigned offset)
150{
151 struct egpio_chip *egpio;
152 struct egpio_info *ei;
153 unsigned bit;
154 int reg;
155 int value;
156
157 pr_debug("egpio_get_value(%d)\n", chip->base + offset);
158
159 egpio = container_of(chip, struct egpio_chip, chip);
160 ei = dev_get_drvdata(egpio->dev);
161 bit = egpio_bit(ei, offset);
162 reg = egpio->reg_start + egpio_pos(ei, offset);
163
164 value = egpio_readw(ei, reg);
165 pr_debug("readw(%p + %x) = %x\n",
166 ei->base_addr, reg << ei->bus_shift, value);
167 return value & bit;
168}
169
170static int egpio_direction_input(struct gpio_chip *chip, unsigned offset)
171{
172 struct egpio_chip *egpio;
173
174 egpio = container_of(chip, struct egpio_chip, chip);
175 return test_bit(offset, &egpio->is_out) ? -EINVAL : 0;
176}
177
178
179/*
180 * Output pins
181 */
182
183static void egpio_set(struct gpio_chip *chip, unsigned offset, int value)
184{
185 unsigned long flag;
186 struct egpio_chip *egpio;
187 struct egpio_info *ei;
188 unsigned bit;
189 int pos;
190 int reg;
191 int shift;
192
193 pr_debug("egpio_set(%s, %d(%d), %d)\n",
194 chip->label, offset, offset+chip->base, value);
195
196 egpio = container_of(chip, struct egpio_chip, chip);
197 ei = dev_get_drvdata(egpio->dev);
198 bit = egpio_bit(ei, offset);
199 pos = egpio_pos(ei, offset);
200 reg = egpio->reg_start + pos;
201 shift = pos << ei->reg_shift;
202
203 pr_debug("egpio %s: reg %d = 0x%04x\n", value ? "set" : "clear",
204 reg, (egpio->cached_values >> shift) & ei->reg_mask);
205
206 spin_lock_irqsave(&ei->lock, flag);
207 if (value)
208 egpio->cached_values |= (1 << offset);
209 else
210 egpio->cached_values &= ~(1 << offset);
211 egpio_writew((egpio->cached_values >> shift) & ei->reg_mask, ei, reg);
212 spin_unlock_irqrestore(&ei->lock, flag);
213}
214
215static int egpio_direction_output(struct gpio_chip *chip,
216 unsigned offset, int value)
217{
218 struct egpio_chip *egpio;
219
220 egpio = container_of(chip, struct egpio_chip, chip);
221 if (test_bit(offset, &egpio->is_out)) {
222 egpio_set(chip, offset, value);
223 return 0;
224 } else {
225 return -EINVAL;
226 }
227}
228
229static void egpio_write_cache(struct egpio_info *ei)
230{
231 int i;
232 struct egpio_chip *egpio;
233 int shift;
234
235 for (i = 0; i < ei->nchips; i++) {
236 egpio = &(ei->chip[i]);
237 if (!egpio->is_out)
238 continue;
239
240 for (shift = 0; shift < egpio->chip.ngpio;
241 shift += (1<<ei->reg_shift)) {
242
243 int reg = egpio->reg_start + egpio_pos(ei, shift);
244
245 if (!((egpio->is_out >> shift) & ei->reg_mask))
246 continue;
247
248 pr_debug("EGPIO: setting %x to %x, was %x\n", reg,
249 (egpio->cached_values >> shift) & ei->reg_mask,
250 egpio_readw(ei, reg));
251
252 egpio_writew((egpio->cached_values >> shift)
253 & ei->reg_mask, ei, reg);
254 }
255 }
256}
257
258
259/*
260 * Setup
261 */
262
263static int __init egpio_probe(struct platform_device *pdev)
264{
265 struct htc_egpio_platform_data *pdata = pdev->dev.platform_data;
266 struct resource *res;
267 struct egpio_info *ei;
268 struct gpio_chip *chip;
269 unsigned int irq, irq_end;
270 int i;
271 int ret;
272
273 /* Initialize ei data structure. */
274 ei = kzalloc(sizeof(*ei), GFP_KERNEL);
275 if (!ei)
276 return -ENOMEM;
277
278 spin_lock_init(&ei->lock);
279
280 /* Find chained irq */
281 ret = -EINVAL;
282 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
283 if (res)
284 ei->chained_irq = res->start;
285
286 /* Map egpio chip into virtual address space. */
287 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
288 if (!res)
289 goto fail;
Philipp Zabel9427c342009-02-04 21:27:48 +0100290 ei->base_addr = ioremap_nocache(res->start, resource_size(res));
Philipp Zabela1635b82008-04-09 19:20:34 +0100291 if (!ei->base_addr)
292 goto fail;
Samuel Ortiz504f97f2008-09-25 00:17:00 +0200293 pr_debug("EGPIO phys=%08x virt=%p\n", (u32)res->start, ei->base_addr);
Philipp Zabela1635b82008-04-09 19:20:34 +0100294
295 if ((pdata->bus_width != 16) && (pdata->bus_width != 32))
296 goto fail;
297 ei->bus_shift = fls(pdata->bus_width - 1) - 3;
298 pr_debug("bus_shift = %d\n", ei->bus_shift);
299
300 if ((pdata->reg_width != 8) && (pdata->reg_width != 16))
301 goto fail;
302 ei->reg_shift = fls(pdata->reg_width - 1);
303 pr_debug("reg_shift = %d\n", ei->reg_shift);
304
305 ei->reg_mask = (1 << pdata->reg_width) - 1;
306
307 platform_set_drvdata(pdev, ei);
308
309 ei->nchips = pdata->num_chips;
310 ei->chip = kzalloc(sizeof(struct egpio_chip) * ei->nchips, GFP_KERNEL);
Julia Lawall720fd662009-02-04 20:44:01 +0100311 if (!ei->chip) {
Philipp Zabela1635b82008-04-09 19:20:34 +0100312 ret = -ENOMEM;
313 goto fail;
314 }
315 for (i = 0; i < ei->nchips; i++) {
316 ei->chip[i].reg_start = pdata->chip[i].reg_start;
317 ei->chip[i].cached_values = pdata->chip[i].initial_values;
318 ei->chip[i].is_out = pdata->chip[i].direction;
319 ei->chip[i].dev = &(pdev->dev);
320 chip = &(ei->chip[i].chip);
321 chip->label = "htc-egpio";
David Brownelld8f388d2008-07-25 01:46:07 -0700322 chip->dev = &pdev->dev;
323 chip->owner = THIS_MODULE;
Philipp Zabela1635b82008-04-09 19:20:34 +0100324 chip->get = egpio_get;
325 chip->set = egpio_set;
326 chip->direction_input = egpio_direction_input;
327 chip->direction_output = egpio_direction_output;
328 chip->base = pdata->chip[i].gpio_base;
329 chip->ngpio = pdata->chip[i].num_gpios;
330
331 gpiochip_add(chip);
332 }
333
334 /* Set initial pin values */
335 egpio_write_cache(ei);
336
337 ei->irq_start = pdata->irq_base;
338 ei->nirqs = pdata->num_irqs;
339 ei->ack_register = pdata->ack_register;
340
341 if (ei->chained_irq) {
342 /* Setup irq handlers */
343 ei->ack_write = 0xFFFF;
344 if (pdata->invert_acks)
345 ei->ack_write = 0;
346 irq_end = ei->irq_start + ei->nirqs;
347 for (irq = ei->irq_start; irq < irq_end; irq++) {
348 set_irq_chip(irq, &egpio_muxed_chip);
349 set_irq_chip_data(irq, ei);
350 set_irq_handler(irq, handle_simple_irq);
351 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
352 }
353 set_irq_type(ei->chained_irq, IRQ_TYPE_EDGE_RISING);
354 set_irq_data(ei->chained_irq, ei);
355 set_irq_chained_handler(ei->chained_irq, egpio_handler);
356 ack_irqs(ei);
357
358 device_init_wakeup(&pdev->dev, 1);
359 }
360
361 return 0;
362
363fail:
364 printk(KERN_ERR "EGPIO failed to setup\n");
365 kfree(ei);
366 return ret;
367}
368
369static int __exit egpio_remove(struct platform_device *pdev)
370{
371 struct egpio_info *ei = platform_get_drvdata(pdev);
372 unsigned int irq, irq_end;
373
374 if (ei->chained_irq) {
375 irq_end = ei->irq_start + ei->nirqs;
376 for (irq = ei->irq_start; irq < irq_end; irq++) {
377 set_irq_chip(irq, NULL);
378 set_irq_handler(irq, NULL);
379 set_irq_flags(irq, 0);
380 }
381 set_irq_chained_handler(ei->chained_irq, NULL);
382 device_init_wakeup(&pdev->dev, 0);
383 }
384 iounmap(ei->base_addr);
385 kfree(ei->chip);
386 kfree(ei);
387
388 return 0;
389}
390
391#ifdef CONFIG_PM
392static int egpio_suspend(struct platform_device *pdev, pm_message_t state)
393{
394 struct egpio_info *ei = platform_get_drvdata(pdev);
395
396 if (ei->chained_irq && device_may_wakeup(&pdev->dev))
397 enable_irq_wake(ei->chained_irq);
398 return 0;
399}
400
401static int egpio_resume(struct platform_device *pdev)
402{
403 struct egpio_info *ei = platform_get_drvdata(pdev);
404
405 if (ei->chained_irq && device_may_wakeup(&pdev->dev))
406 disable_irq_wake(ei->chained_irq);
407
408 /* Update registers from the cache, in case
409 the CPLD was powered off during suspend */
410 egpio_write_cache(ei);
411 return 0;
412}
413#else
414#define egpio_suspend NULL
415#define egpio_resume NULL
416#endif
417
418
419static struct platform_driver egpio_driver = {
420 .driver = {
421 .name = "htc-egpio",
422 },
423 .remove = __exit_p(egpio_remove),
424 .suspend = egpio_suspend,
425 .resume = egpio_resume,
426};
427
428static int __init egpio_init(void)
429{
430 return platform_driver_probe(&egpio_driver, egpio_probe);
431}
432
433static void __exit egpio_exit(void)
434{
435 platform_driver_unregister(&egpio_driver);
436}
437
438/* start early for dependencies */
439subsys_initcall(egpio_init);
440module_exit(egpio_exit)
441
442MODULE_LICENSE("GPL");
443MODULE_AUTHOR("Kevin O'Connor <kevin@koconnor.net>");