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Diffstat (limited to 'drivers/gpio/gpio-twl4030.c')
-rw-r--r--drivers/gpio/gpio-twl4030.c513
1 files changed, 513 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-twl4030.c b/drivers/gpio/gpio-twl4030.c
new file mode 100644
index 000000000000..b8b4f228757c
--- /dev/null
+++ b/drivers/gpio/gpio-twl4030.c
@@ -0,0 +1,513 @@
1/*
2 * Access to GPIOs on TWL4030/TPS659x0 chips
3 *
4 * Copyright (C) 2006-2007 Texas Instruments, Inc.
5 * Copyright (C) 2006 MontaVista Software, Inc.
6 *
7 * Code re-arranged and cleaned up by:
8 * Syed Mohammed Khasim <x0khasim@ti.com>
9 *
10 * Initial Code:
11 * Andy Lowe / Nishanth Menon
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
17 *
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
22 *
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 */
27
28#include <linux/module.h>
29#include <linux/init.h>
30#include <linux/interrupt.h>
31#include <linux/kthread.h>
32#include <linux/irq.h>
33#include <linux/gpio.h>
34#include <linux/platform_device.h>
35
36#include <linux/i2c/twl.h>
37
38
39/*
40 * The GPIO "subchip" supports 18 GPIOs which can be configured as
41 * inputs or outputs, with pullups or pulldowns on each pin. Each
42 * GPIO can trigger interrupts on either or both edges.
43 *
44 * GPIO interrupts can be fed to either of two IRQ lines; this is
45 * intended to support multiple hosts.
46 *
47 * There are also two LED pins used sometimes as output-only GPIOs.
48 */
49
50
51static struct gpio_chip twl_gpiochip;
52static int twl4030_gpio_irq_base;
53
54/* genirq interfaces are not available to modules */
55#ifdef MODULE
56#define is_module() true
57#else
58#define is_module() false
59#endif
60
61/* GPIO_CTRL Fields */
62#define MASK_GPIO_CTRL_GPIO0CD1 BIT(0)
63#define MASK_GPIO_CTRL_GPIO1CD2 BIT(1)
64#define MASK_GPIO_CTRL_GPIO_ON BIT(2)
65
66/* Mask for GPIO registers when aggregated into a 32-bit integer */
67#define GPIO_32_MASK 0x0003ffff
68
69/* Data structures */
70static DEFINE_MUTEX(gpio_lock);
71
72/* store usage of each GPIO. - each bit represents one GPIO */
73static unsigned int gpio_usage_count;
74
75/*----------------------------------------------------------------------*/
76
77/*
78 * To configure TWL4030 GPIO module registers
79 */
80static inline int gpio_twl4030_write(u8 address, u8 data)
81{
82 return twl_i2c_write_u8(TWL4030_MODULE_GPIO, data, address);
83}
84
85/*----------------------------------------------------------------------*/
86
87/*
88 * LED register offsets (use TWL4030_MODULE_{LED,PWMA,PWMB}))
89 * PWMs A and B are dedicated to LEDs A and B, respectively.
90 */
91
92#define TWL4030_LED_LEDEN 0x0
93
94/* LEDEN bits */
95#define LEDEN_LEDAON BIT(0)
96#define LEDEN_LEDBON BIT(1)
97#define LEDEN_LEDAEXT BIT(2)
98#define LEDEN_LEDBEXT BIT(3)
99#define LEDEN_LEDAPWM BIT(4)
100#define LEDEN_LEDBPWM BIT(5)
101#define LEDEN_PWM_LENGTHA BIT(6)
102#define LEDEN_PWM_LENGTHB BIT(7)
103
104#define TWL4030_PWMx_PWMxON 0x0
105#define TWL4030_PWMx_PWMxOFF 0x1
106
107#define PWMxON_LENGTH BIT(7)
108
109/*----------------------------------------------------------------------*/
110
111/*
112 * To read a TWL4030 GPIO module register
113 */
114static inline int gpio_twl4030_read(u8 address)
115{
116 u8 data;
117 int ret = 0;
118
119 ret = twl_i2c_read_u8(TWL4030_MODULE_GPIO, &data, address);
120 return (ret < 0) ? ret : data;
121}
122
123/*----------------------------------------------------------------------*/
124
125static u8 cached_leden; /* protected by gpio_lock */
126
127/* The LED lines are open drain outputs ... a FET pulls to GND, so an
128 * external pullup is needed. We could also expose the integrated PWM
129 * as a LED brightness control; we initialize it as "always on".
130 */
131static void twl4030_led_set_value(int led, int value)
132{
133 u8 mask = LEDEN_LEDAON | LEDEN_LEDAPWM;
134 int status;
135
136 if (led)
137 mask <<= 1;
138
139 mutex_lock(&gpio_lock);
140 if (value)
141 cached_leden &= ~mask;
142 else
143 cached_leden |= mask;
144 status = twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden,
145 TWL4030_LED_LEDEN);
146 mutex_unlock(&gpio_lock);
147}
148
149static int twl4030_set_gpio_direction(int gpio, int is_input)
150{
151 u8 d_bnk = gpio >> 3;
152 u8 d_msk = BIT(gpio & 0x7);
153 u8 reg = 0;
154 u8 base = REG_GPIODATADIR1 + d_bnk;
155 int ret = 0;
156
157 mutex_lock(&gpio_lock);
158 ret = gpio_twl4030_read(base);
159 if (ret >= 0) {
160 if (is_input)
161 reg = ret & ~d_msk;
162 else
163 reg = ret | d_msk;
164
165 ret = gpio_twl4030_write(base, reg);
166 }
167 mutex_unlock(&gpio_lock);
168 return ret;
169}
170
171static int twl4030_set_gpio_dataout(int gpio, int enable)
172{
173 u8 d_bnk = gpio >> 3;
174 u8 d_msk = BIT(gpio & 0x7);
175 u8 base = 0;
176
177 if (enable)
178 base = REG_SETGPIODATAOUT1 + d_bnk;
179 else
180 base = REG_CLEARGPIODATAOUT1 + d_bnk;
181
182 return gpio_twl4030_write(base, d_msk);
183}
184
185static int twl4030_get_gpio_datain(int gpio)
186{
187 u8 d_bnk = gpio >> 3;
188 u8 d_off = gpio & 0x7;
189 u8 base = 0;
190 int ret = 0;
191
192 if (unlikely((gpio >= TWL4030_GPIO_MAX)
193 || !(gpio_usage_count & BIT(gpio))))
194 return -EPERM;
195
196 base = REG_GPIODATAIN1 + d_bnk;
197 ret = gpio_twl4030_read(base);
198 if (ret > 0)
199 ret = (ret >> d_off) & 0x1;
200
201 return ret;
202}
203
204/*----------------------------------------------------------------------*/
205
206static int twl_request(struct gpio_chip *chip, unsigned offset)
207{
208 int status = 0;
209
210 mutex_lock(&gpio_lock);
211
212 /* Support the two LED outputs as output-only GPIOs. */
213 if (offset >= TWL4030_GPIO_MAX) {
214 u8 ledclr_mask = LEDEN_LEDAON | LEDEN_LEDAEXT
215 | LEDEN_LEDAPWM | LEDEN_PWM_LENGTHA;
216 u8 module = TWL4030_MODULE_PWMA;
217
218 offset -= TWL4030_GPIO_MAX;
219 if (offset) {
220 ledclr_mask <<= 1;
221 module = TWL4030_MODULE_PWMB;
222 }
223
224 /* initialize PWM to always-drive */
225 status = twl_i2c_write_u8(module, 0x7f,
226 TWL4030_PWMx_PWMxOFF);
227 if (status < 0)
228 goto done;
229 status = twl_i2c_write_u8(module, 0x7f,
230 TWL4030_PWMx_PWMxON);
231 if (status < 0)
232 goto done;
233
234 /* init LED to not-driven (high) */
235 module = TWL4030_MODULE_LED;
236 status = twl_i2c_read_u8(module, &cached_leden,
237 TWL4030_LED_LEDEN);
238 if (status < 0)
239 goto done;
240 cached_leden &= ~ledclr_mask;
241 status = twl_i2c_write_u8(module, cached_leden,
242 TWL4030_LED_LEDEN);
243 if (status < 0)
244 goto done;
245
246 status = 0;
247 goto done;
248 }
249
250 /* on first use, turn GPIO module "on" */
251 if (!gpio_usage_count) {
252 struct twl4030_gpio_platform_data *pdata;
253 u8 value = MASK_GPIO_CTRL_GPIO_ON;
254
255 /* optionally have the first two GPIOs switch vMMC1
256 * and vMMC2 power supplies based on card presence.
257 */
258 pdata = chip->dev->platform_data;
259 value |= pdata->mmc_cd & 0x03;
260
261 status = gpio_twl4030_write(REG_GPIO_CTRL, value);
262 }
263
264 if (!status)
265 gpio_usage_count |= (0x1 << offset);
266
267done:
268 mutex_unlock(&gpio_lock);
269 return status;
270}
271
272static void twl_free(struct gpio_chip *chip, unsigned offset)
273{
274 if (offset >= TWL4030_GPIO_MAX) {
275 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, 1);
276 return;
277 }
278
279 mutex_lock(&gpio_lock);
280
281 gpio_usage_count &= ~BIT(offset);
282
283 /* on last use, switch off GPIO module */
284 if (!gpio_usage_count)
285 gpio_twl4030_write(REG_GPIO_CTRL, 0x0);
286
287 mutex_unlock(&gpio_lock);
288}
289
290static int twl_direction_in(struct gpio_chip *chip, unsigned offset)
291{
292 return (offset < TWL4030_GPIO_MAX)
293 ? twl4030_set_gpio_direction(offset, 1)
294 : -EINVAL;
295}
296
297static int twl_get(struct gpio_chip *chip, unsigned offset)
298{
299 int status = 0;
300
301 if (offset < TWL4030_GPIO_MAX)
302 status = twl4030_get_gpio_datain(offset);
303 else if (offset == TWL4030_GPIO_MAX)
304 status = cached_leden & LEDEN_LEDAON;
305 else
306 status = cached_leden & LEDEN_LEDBON;
307 return (status < 0) ? 0 : status;
308}
309
310static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value)
311{
312 if (offset < TWL4030_GPIO_MAX) {
313 twl4030_set_gpio_dataout(offset, value);
314 return twl4030_set_gpio_direction(offset, 0);
315 } else {
316 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value);
317 return 0;
318 }
319}
320
321static void twl_set(struct gpio_chip *chip, unsigned offset, int value)
322{
323 if (offset < TWL4030_GPIO_MAX)
324 twl4030_set_gpio_dataout(offset, value);
325 else
326 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value);
327}
328
329static int twl_to_irq(struct gpio_chip *chip, unsigned offset)
330{
331 return (twl4030_gpio_irq_base && (offset < TWL4030_GPIO_MAX))
332 ? (twl4030_gpio_irq_base + offset)
333 : -EINVAL;
334}
335
336static struct gpio_chip twl_gpiochip = {
337 .label = "twl4030",
338 .owner = THIS_MODULE,
339 .request = twl_request,
340 .free = twl_free,
341 .direction_input = twl_direction_in,
342 .get = twl_get,
343 .direction_output = twl_direction_out,
344 .set = twl_set,
345 .to_irq = twl_to_irq,
346 .can_sleep = 1,
347};
348
349/*----------------------------------------------------------------------*/
350
351static int __devinit gpio_twl4030_pulls(u32 ups, u32 downs)
352{
353 u8 message[6];
354 unsigned i, gpio_bit;
355
356 /* For most pins, a pulldown was enabled by default.
357 * We should have data that's specific to this board.
358 */
359 for (gpio_bit = 1, i = 1; i < 6; i++) {
360 u8 bit_mask;
361 unsigned j;
362
363 for (bit_mask = 0, j = 0; j < 8; j += 2, gpio_bit <<= 1) {
364 if (ups & gpio_bit)
365 bit_mask |= 1 << (j + 1);
366 else if (downs & gpio_bit)
367 bit_mask |= 1 << (j + 0);
368 }
369 message[i] = bit_mask;
370 }
371
372 return twl_i2c_write(TWL4030_MODULE_GPIO, message,
373 REG_GPIOPUPDCTR1, 5);
374}
375
376static int __devinit gpio_twl4030_debounce(u32 debounce, u8 mmc_cd)
377{
378 u8 message[4];
379
380 /* 30 msec of debouncing is always used for MMC card detect,
381 * and is optional for everything else.
382 */
383 message[1] = (debounce & 0xff) | (mmc_cd & 0x03);
384 debounce >>= 8;
385 message[2] = (debounce & 0xff);
386 debounce >>= 8;
387 message[3] = (debounce & 0x03);
388
389 return twl_i2c_write(TWL4030_MODULE_GPIO, message,
390 REG_GPIO_DEBEN1, 3);
391}
392
393static int gpio_twl4030_remove(struct platform_device *pdev);
394
395static int __devinit gpio_twl4030_probe(struct platform_device *pdev)
396{
397 struct twl4030_gpio_platform_data *pdata = pdev->dev.platform_data;
398 int ret;
399
400 /* maybe setup IRQs */
401 if (pdata->irq_base) {
402 if (is_module()) {
403 dev_err(&pdev->dev,
404 "can't dispatch IRQs from modules\n");
405 goto no_irqs;
406 }
407 ret = twl4030_sih_setup(TWL4030_MODULE_GPIO);
408 if (ret < 0)
409 return ret;
410 WARN_ON(ret != pdata->irq_base);
411 twl4030_gpio_irq_base = ret;
412 }
413
414no_irqs:
415 /*
416 * NOTE: boards may waste power if they don't set pullups
417 * and pulldowns correctly ... default for non-ULPI pins is
418 * pulldown, and some other pins may have external pullups
419 * or pulldowns. Careful!
420 */
421 ret = gpio_twl4030_pulls(pdata->pullups, pdata->pulldowns);
422 if (ret)
423 dev_dbg(&pdev->dev, "pullups %.05x %.05x --> %d\n",
424 pdata->pullups, pdata->pulldowns,
425 ret);
426
427 ret = gpio_twl4030_debounce(pdata->debounce, pdata->mmc_cd);
428 if (ret)
429 dev_dbg(&pdev->dev, "debounce %.03x %.01x --> %d\n",
430 pdata->debounce, pdata->mmc_cd,
431 ret);
432
433 twl_gpiochip.base = pdata->gpio_base;
434 twl_gpiochip.ngpio = TWL4030_GPIO_MAX;
435 twl_gpiochip.dev = &pdev->dev;
436
437 /* NOTE: we assume VIBRA_CTL.VIBRA_EN, in MODULE_AUDIO_VOICE,
438 * is (still) clear if use_leds is set.
439 */
440 if (pdata->use_leds)
441 twl_gpiochip.ngpio += 2;
442
443 ret = gpiochip_add(&twl_gpiochip);
444 if (ret < 0) {
445 dev_err(&pdev->dev,
446 "could not register gpiochip, %d\n",
447 ret);
448 twl_gpiochip.ngpio = 0;
449 gpio_twl4030_remove(pdev);
450 } else if (pdata->setup) {
451 int status;
452
453 status = pdata->setup(&pdev->dev,
454 pdata->gpio_base, TWL4030_GPIO_MAX);
455 if (status)
456 dev_dbg(&pdev->dev, "setup --> %d\n", status);
457 }
458
459 return ret;
460}
461
462/* Cannot use __devexit as gpio_twl4030_probe() calls us */
463static int gpio_twl4030_remove(struct platform_device *pdev)
464{
465 struct twl4030_gpio_platform_data *pdata = pdev->dev.platform_data;
466 int status;
467
468 if (pdata->teardown) {
469 status = pdata->teardown(&pdev->dev,
470 pdata->gpio_base, TWL4030_GPIO_MAX);
471 if (status) {
472 dev_dbg(&pdev->dev, "teardown --> %d\n", status);
473 return status;
474 }
475 }
476
477 status = gpiochip_remove(&twl_gpiochip);
478 if (status < 0)
479 return status;
480
481 if (is_module())
482 return 0;
483
484 /* REVISIT no support yet for deregistering all the IRQs */
485 WARN_ON(1);
486 return -EIO;
487}
488
489/* Note: this hardware lives inside an I2C-based multi-function device. */
490MODULE_ALIAS("platform:twl4030_gpio");
491
492static struct platform_driver gpio_twl4030_driver = {
493 .driver.name = "twl4030_gpio",
494 .driver.owner = THIS_MODULE,
495 .probe = gpio_twl4030_probe,
496 .remove = gpio_twl4030_remove,
497};
498
499static int __init gpio_twl4030_init(void)
500{
501 return platform_driver_register(&gpio_twl4030_driver);
502}
503subsys_initcall(gpio_twl4030_init);
504
505static void __exit gpio_twl4030_exit(void)
506{
507 platform_driver_unregister(&gpio_twl4030_driver);
508}
509module_exit(gpio_twl4030_exit);
510
511MODULE_AUTHOR("Texas Instruments, Inc.");
512MODULE_DESCRIPTION("GPIO interface for TWL4030");
513MODULE_LICENSE("GPL");