2 * twl4030_gpio.c -- access to GPIOs on TWL4030/TPS659x0 chips
4 * Copyright (C) 2006-2007 Texas Instruments, Inc.
5 * Copyright (C) 2006 MontaVista Software, Inc.
7 * Code re-arranged and cleaned up by:
8 * Syed Mohammed Khasim <x0khasim@ti.com>
11 * Andy Lowe / Nishanth Menon
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.
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.
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
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 #include <linux/slab.h>
37 #include <linux/i2c/twl4030.h>
41 * The GPIO "subchip" supports 18 GPIOs which can be configured as
42 * inputs or outputs, with pullups or pulldowns on each pin. Each
43 * GPIO can trigger interrupts on either or both edges.
45 * GPIO interrupts can be fed to either of two IRQ lines; this is
46 * intended to support multiple hosts.
48 * There are also two LED pins used sometimes as output-only GPIOs.
50 * FIXME code currently only handles the first IRQ line.
54 static struct gpio_chip twl_gpiochip;
55 static int twl4030_gpio_irq_base;
57 /* genirq interfaces are not available to modules */
59 #define is_module() true
61 #define is_module() false
64 /* GPIO_CTRL Fields */
65 #define MASK_GPIO_CTRL_GPIO0CD1 BIT(0)
66 #define MASK_GPIO_CTRL_GPIO1CD2 BIT(1)
67 #define MASK_GPIO_CTRL_GPIO_ON BIT(2)
69 /* Mask for GPIO registers when aggregated into a 32-bit integer */
70 #define GPIO_32_MASK 0x0003ffff
73 static DEFINE_MUTEX(gpio_lock);
75 /* store usage of each GPIO. - each bit represents one GPIO */
76 static unsigned int gpio_usage_count;
78 /*----------------------------------------------------------------------*/
81 * To configure TWL4030 GPIO module registers
83 static inline int gpio_twl4030_write(u8 address, u8 data)
85 return twl4030_i2c_write_u8(TWL4030_MODULE_GPIO, data, address);
88 /*----------------------------------------------------------------------*/
91 * LED register offsets (use TWL4030_MODULE_{LED,PWMA,PWMB}))
92 * PWMs A and B are dedicated to LEDs A and B, respectively.
95 #define TWL4030_LED_LEDEN 0x0
98 #define LEDEN_LEDAON BIT(0)
99 #define LEDEN_LEDBON BIT(1)
100 #define LEDEN_LEDAEXT BIT(2)
101 #define LEDEN_LEDBEXT BIT(3)
102 #define LEDEN_LEDAPWM BIT(4)
103 #define LEDEN_LEDBPWM BIT(5)
104 #define LEDEN_PWM_LENGTHA BIT(6)
105 #define LEDEN_PWM_LENGTHB BIT(7)
107 #define TWL4030_PWMx_PWMxON 0x0
108 #define TWL4030_PWMx_PWMxOFF 0x1
110 #define PWMxON_LENGTH BIT(7)
112 /*----------------------------------------------------------------------*/
115 * To read a TWL4030 GPIO module register
117 static inline int gpio_twl4030_read(u8 address)
122 ret = twl4030_i2c_read_u8(TWL4030_MODULE_GPIO, &data, address);
123 return (ret < 0) ? ret : data;
126 /*----------------------------------------------------------------------*/
128 static u8 cached_leden; /* protected by gpio_lock */
130 /* The LED lines are open drain outputs ... a FET pulls to GND, so an
131 * external pullup is needed. We could also expose the integrated PWM
132 * as a LED brightness control; we initialize it as "always on".
134 static void twl4030_led_set_value(int led, int value)
136 u8 mask = LEDEN_LEDAON | LEDEN_LEDAPWM;
142 mutex_lock(&gpio_lock);
144 cached_leden &= ~mask;
146 cached_leden |= mask;
147 status = twl4030_i2c_write_u8(TWL4030_MODULE_LED, cached_leden,
149 mutex_unlock(&gpio_lock);
152 static int twl4030_set_gpio_direction(int gpio, int is_input)
154 u8 d_bnk = gpio >> 3;
155 u8 d_msk = BIT(gpio & 0x7);
157 u8 base = REG_GPIODATADIR1 + d_bnk;
160 mutex_lock(&gpio_lock);
161 ret = gpio_twl4030_read(base);
168 ret = gpio_twl4030_write(base, reg);
170 mutex_unlock(&gpio_lock);
174 static int twl4030_set_gpio_dataout(int gpio, int enable)
176 u8 d_bnk = gpio >> 3;
177 u8 d_msk = BIT(gpio & 0x7);
181 base = REG_SETGPIODATAOUT1 + d_bnk;
183 base = REG_CLEARGPIODATAOUT1 + d_bnk;
185 return gpio_twl4030_write(base, d_msk);
188 static int twl4030_get_gpio_datain(int gpio)
190 u8 d_bnk = gpio >> 3;
191 u8 d_off = gpio & 0x7;
195 if (unlikely((gpio >= TWL4030_GPIO_MAX)
196 || !(gpio_usage_count & BIT(gpio))))
199 base = REG_GPIODATAIN1 + d_bnk;
200 ret = gpio_twl4030_read(base);
202 ret = (ret >> d_off) & 0x1;
208 * Configure debounce timing value for a GPIO pin on TWL4030
210 int twl4030_set_gpio_debounce(int gpio, int enable)
212 u8 d_bnk = gpio >> 3;
213 u8 d_msk = BIT(gpio & 0x7);
218 if (unlikely((gpio >= TWL4030_GPIO_MAX)
219 || !(gpio_usage_count & BIT(gpio))))
222 base = REG_GPIO_DEBEN1 + d_bnk;
223 mutex_lock(&gpio_lock);
224 ret = gpio_twl4030_read(base);
231 ret = gpio_twl4030_write(base, reg);
233 mutex_unlock(&gpio_lock);
236 EXPORT_SYMBOL(twl4030_set_gpio_debounce);
240 * Configure Card detect for GPIO pin on TWL4030
242 * This means: VMMC1 or VMMC2 is enabled or disabled based
243 * on the status of GPIO-0 or GPIO-1 pins (respectively).
245 int twl4030_set_gpio_card_detect(int gpio, int enable)
248 u8 msk = (1 << gpio);
251 /* Only GPIO 0 or 1 can be used for CD feature.. */
252 if (unlikely((gpio >= TWL4030_GPIO_MAX)
253 || !(gpio_usage_count & BIT(gpio))
254 || (gpio >= TWL4030_GPIO_MAX_CD))) {
258 mutex_lock(&gpio_lock);
259 ret = gpio_twl4030_read(REG_GPIO_CTRL);
262 reg = (u8) (ret | msk);
264 reg = (u8) (ret & ~msk);
266 ret = gpio_twl4030_write(REG_GPIO_CTRL, reg);
268 mutex_unlock(&gpio_lock);
273 /*----------------------------------------------------------------------*/
275 static int twl_request(struct gpio_chip *chip, unsigned offset)
279 mutex_lock(&gpio_lock);
281 /* Support the two LED outputs as output-only GPIOs. */
282 if (offset >= TWL4030_GPIO_MAX) {
283 u8 ledclr_mask = LEDEN_LEDAON | LEDEN_LEDAEXT
284 | LEDEN_LEDAPWM | LEDEN_PWM_LENGTHA;
285 u8 module = TWL4030_MODULE_PWMA;
287 offset -= TWL4030_GPIO_MAX;
290 module = TWL4030_MODULE_PWMB;
293 /* initialize PWM to always-drive */
294 status = twl4030_i2c_write_u8(module, 0x7f,
295 TWL4030_PWMx_PWMxOFF);
298 status = twl4030_i2c_write_u8(module, 0x7f,
299 TWL4030_PWMx_PWMxON);
303 /* init LED to not-driven (high) */
304 module = TWL4030_MODULE_LED;
305 status = twl4030_i2c_read_u8(module, &cached_leden,
309 cached_leden &= ~ledclr_mask;
310 status = twl4030_i2c_write_u8(module, cached_leden,
319 /* on first use, turn GPIO module "on" */
320 if (!gpio_usage_count)
321 status = gpio_twl4030_write(REG_GPIO_CTRL,
322 MASK_GPIO_CTRL_GPIO_ON);
325 gpio_usage_count |= (0x1 << offset);
328 mutex_unlock(&gpio_lock);
332 static void twl_free(struct gpio_chip *chip, unsigned offset)
334 if (offset >= TWL4030_GPIO_MAX) {
335 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, 1);
339 mutex_lock(&gpio_lock);
341 gpio_usage_count &= ~BIT(offset);
343 /* on last use, switch off GPIO module */
344 if (!gpio_usage_count)
345 gpio_twl4030_write(REG_GPIO_CTRL, 0x0);
347 mutex_unlock(&gpio_lock);
350 static int twl_direction_in(struct gpio_chip *chip, unsigned offset)
352 return (offset < TWL4030_GPIO_MAX)
353 ? twl4030_set_gpio_direction(offset, 1)
357 static int twl_get(struct gpio_chip *chip, unsigned offset)
361 if (offset < TWL4030_GPIO_MAX)
362 status = twl4030_get_gpio_datain(offset);
363 else if (offset == TWL4030_GPIO_MAX)
364 status = cached_leden & LEDEN_LEDAON;
366 status = cached_leden & LEDEN_LEDBON;
367 return (status < 0) ? 0 : status;
370 static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value)
372 if (offset < TWL4030_GPIO_MAX) {
373 twl4030_set_gpio_dataout(offset, value);
374 return twl4030_set_gpio_direction(offset, 0);
376 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value);
381 static void twl_set(struct gpio_chip *chip, unsigned offset, int value)
383 if (offset < TWL4030_GPIO_MAX)
384 twl4030_set_gpio_dataout(offset, value);
386 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value);
389 static int twl_to_irq(struct gpio_chip *chip, unsigned offset)
391 return (twl4030_gpio_irq_base && (offset < TWL4030_GPIO_MAX))
392 ? (twl4030_gpio_irq_base + offset)
396 static struct gpio_chip twl_gpiochip = {
398 .owner = THIS_MODULE,
399 .request = twl_request,
401 .direction_input = twl_direction_in,
403 .direction_output = twl_direction_out,
405 .to_irq = twl_to_irq,
409 /*----------------------------------------------------------------------*/
411 static int __devinit gpio_twl4030_pulls(u32 ups, u32 downs)
414 unsigned i, gpio_bit;
416 /* For most pins, a pulldown was enabled by default.
417 * We should have data that's specific to this board.
419 for (gpio_bit = 1, i = 1; i < 6; i++) {
423 for (bit_mask = 0, j = 0; j < 8; j += 2, gpio_bit <<= 1) {
425 bit_mask |= 1 << (j + 1);
426 else if (downs & gpio_bit)
427 bit_mask |= 1 << (j + 0);
429 message[i] = bit_mask;
432 return twl4030_i2c_write(TWL4030_MODULE_GPIO, message,
433 REG_GPIOPUPDCTR1, 5);
436 static int gpio_twl4030_remove(struct platform_device *pdev);
438 static int __devinit gpio_twl4030_probe(struct platform_device *pdev)
440 struct twl4030_gpio_platform_data *pdata = pdev->dev.platform_data;
443 /* maybe setup IRQs */
444 if (pdata->irq_base) {
447 "can't dispatch IRQs from modules\n");
450 ret = twl4030_sih_setup(TWL4030_MODULE_GPIO);
453 WARN_ON(ret != pdata->irq_base);
454 twl4030_gpio_irq_base = ret;
459 * NOTE: boards may waste power if they don't set pullups
460 * and pulldowns correctly ... default for non-ULPI pins is
461 * pulldown, and some other pins may have external pullups
462 * or pulldowns. Careful!
464 ret = gpio_twl4030_pulls(pdata->pullups, pdata->pulldowns);
466 dev_dbg(&pdev->dev, "pullups %.05x %.05x --> %d\n",
467 pdata->pullups, pdata->pulldowns,
470 twl_gpiochip.base = pdata->gpio_base;
471 twl_gpiochip.ngpio = TWL4030_GPIO_MAX;
472 twl_gpiochip.dev = &pdev->dev;
474 /* NOTE: we assume VIBRA_CTL.VIBRA_EN, in MODULE_AUDIO_VOICE,
475 * is (still) clear if use_leds is set.
478 twl_gpiochip.ngpio += 2;
480 ret = gpiochip_add(&twl_gpiochip);
483 "could not register gpiochip, %d\n",
485 twl_gpiochip.ngpio = 0;
486 gpio_twl4030_remove(pdev);
487 } else if (pdata->setup) {
490 status = pdata->setup(&pdev->dev,
491 pdata->gpio_base, TWL4030_GPIO_MAX);
493 dev_dbg(&pdev->dev, "setup --> %d\n", status);
499 static int __devexit gpio_twl4030_remove(struct platform_device *pdev)
501 struct twl4030_gpio_platform_data *pdata = pdev->dev.platform_data;
504 if (pdata->teardown) {
505 status = pdata->teardown(&pdev->dev,
506 pdata->gpio_base, TWL4030_GPIO_MAX);
508 dev_dbg(&pdev->dev, "teardown --> %d\n", status);
513 status = gpiochip_remove(&twl_gpiochip);
520 /* REVISIT no support yet for deregistering all the IRQs */
525 /* Note: this hardware lives inside an I2C-based multi-function device. */
526 MODULE_ALIAS("platform:twl4030_gpio");
528 static struct platform_driver gpio_twl4030_driver = {
529 .driver.name = "twl4030_gpio",
530 .driver.owner = THIS_MODULE,
531 .probe = gpio_twl4030_probe,
532 .remove = __devexit_p(gpio_twl4030_remove),
535 static int __init gpio_twl4030_init(void)
537 return platform_driver_register(&gpio_twl4030_driver);
539 subsys_initcall(gpio_twl4030_init);
541 static void __exit gpio_twl4030_exit(void)
543 platform_driver_unregister(&gpio_twl4030_driver);
545 module_exit(gpio_twl4030_exit);
547 MODULE_AUTHOR("Texas Instruments, Inc.");
548 MODULE_DESCRIPTION("GPIO interface for TWL4030");
549 MODULE_LICENSE("GPL");