2 * Intel ICH6-10, Series 5 and 6, Atom C2000 (Avoton/Rangeley) GPIO driver
4 * Copyright (C) 2010 Extreme Engineering Solutions.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 #include <linux/ioport.h>
23 #include <linux/module.h>
24 #include <linux/pci.h>
25 #include <linux/gpio/driver.h>
26 #include <linux/platform_device.h>
27 #include <linux/mfd/lpc_ich.h>
28 #include <linux/bitops.h>
30 #define DRV_NAME "gpio_ich"
33 * GPIO register offsets in GPIO I/O space.
34 * Each chunk of 32 GPIOs is manipulated via its own USE_SELx, IO_SELx, and
35 * LVLx registers. Logic in the read/write functions takes a register and
36 * an absolute bit number and determines the proper register offset and bit
37 * number in that register. For example, to read the value of GPIO bit 50
38 * the code would access offset ichx_regs[2(=GPIO_LVL)][1(=50/32)],
48 static const u8 ichx_regs[4][3] = {
49 {0x00, 0x30, 0x40}, /* USE_SEL[1-3] offsets */
50 {0x04, 0x34, 0x44}, /* IO_SEL[1-3] offsets */
51 {0x0c, 0x38, 0x48}, /* LVL[1-3] offsets */
52 {0x18, 0x18, 0x18}, /* BLINK offset */
55 static const u8 ichx_reglen[3] = {
59 static const u8 avoton_regs[4][3] = {
65 static const u8 avoton_reglen[3] = {
69 #define ICHX_WRITE(val, reg, base_res) outl(val, (reg) + (base_res)->start)
70 #define ICHX_READ(reg, base_res) inl((reg) + (base_res)->start)
73 /* Max GPIO pins the chipset can have */
76 /* chipset registers */
80 /* GPO_BLINK is available on this chipset */
83 /* Whether the chipset has GPIO in GPE0_STS in the PM IO region */
86 /* USE_SEL is bogus on some chipsets, eg 3100 */
87 u32 use_sel_ignore[3];
89 /* Some chipsets have quirks, let these use their own request/get */
90 int (*request)(struct gpio_chip *chip, unsigned offset);
91 int (*get)(struct gpio_chip *chip, unsigned offset);
94 * Some chipsets don't let reading output values on GPIO_LVL register
95 * this option allows driver caching written output values
97 bool use_outlvl_cache;
103 struct gpio_chip chip;
104 struct resource *gpio_base; /* GPIO IO base */
105 struct resource *pm_base; /* Power Mangagment IO base */
106 struct ichx_desc *desc; /* Pointer to chipset-specific description */
107 u32 orig_gpio_ctrl; /* Orig CTRL value, used to restore on exit */
108 u8 use_gpio; /* Which GPIO groups are usable */
109 int outlvl_cache[3]; /* cached output values */
112 static int modparam_gpiobase = -1; /* dynamic */
113 module_param_named(gpiobase, modparam_gpiobase, int, 0444);
114 MODULE_PARM_DESC(gpiobase, "The GPIO number base. -1 means dynamic, which is the default.");
116 static int ichx_write_bit(int reg, unsigned nr, int val, int verify)
120 int reg_nr = nr / 32;
123 spin_lock_irqsave(&ichx_priv.lock, flags);
125 if (reg == GPIO_LVL && ichx_priv.desc->use_outlvl_cache)
126 data = ichx_priv.outlvl_cache[reg_nr];
128 data = ICHX_READ(ichx_priv.desc->regs[reg][reg_nr],
129 ichx_priv.gpio_base);
135 ICHX_WRITE(data, ichx_priv.desc->regs[reg][reg_nr],
136 ichx_priv.gpio_base);
137 if (reg == GPIO_LVL && ichx_priv.desc->use_outlvl_cache)
138 ichx_priv.outlvl_cache[reg_nr] = data;
140 tmp = ICHX_READ(ichx_priv.desc->regs[reg][reg_nr],
141 ichx_priv.gpio_base);
143 spin_unlock_irqrestore(&ichx_priv.lock, flags);
145 return (verify && data != tmp) ? -EPERM : 0;
148 static int ichx_read_bit(int reg, unsigned nr)
152 int reg_nr = nr / 32;
155 spin_lock_irqsave(&ichx_priv.lock, flags);
157 data = ICHX_READ(ichx_priv.desc->regs[reg][reg_nr],
158 ichx_priv.gpio_base);
160 if (reg == GPIO_LVL && ichx_priv.desc->use_outlvl_cache)
161 data = ichx_priv.outlvl_cache[reg_nr] | data;
163 spin_unlock_irqrestore(&ichx_priv.lock, flags);
165 return !!(data & BIT(bit));
168 static bool ichx_gpio_check_available(struct gpio_chip *gpio, unsigned nr)
170 return !!(ichx_priv.use_gpio & BIT(nr / 32));
173 static int ichx_gpio_get_direction(struct gpio_chip *gpio, unsigned nr)
175 return ichx_read_bit(GPIO_IO_SEL, nr);
178 static int ichx_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
181 * Try setting pin as an input and verify it worked since many pins
184 return ichx_write_bit(GPIO_IO_SEL, nr, 1, 1);
187 static int ichx_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
190 /* Disable blink hardware which is available for GPIOs from 0 to 31. */
191 if (nr < 32 && ichx_priv.desc->have_blink)
192 ichx_write_bit(GPO_BLINK, nr, 0, 0);
194 /* Set GPIO output value. */
195 ichx_write_bit(GPIO_LVL, nr, val, 0);
198 * Try setting pin as an output and verify it worked since many pins
201 return ichx_write_bit(GPIO_IO_SEL, nr, 0, 1);
204 static int ichx_gpio_get(struct gpio_chip *chip, unsigned nr)
206 return ichx_read_bit(GPIO_LVL, nr);
209 static int ich6_gpio_get(struct gpio_chip *chip, unsigned nr)
215 * GPI 0 - 15 need to be read from the power management registers on
216 * a ICH6/3100 bridge.
219 if (!ichx_priv.pm_base)
222 spin_lock_irqsave(&ichx_priv.lock, flags);
224 /* GPI 0 - 15 are latched, write 1 to clear*/
225 ICHX_WRITE(BIT(16 + nr), 0, ichx_priv.pm_base);
226 data = ICHX_READ(0, ichx_priv.pm_base);
228 spin_unlock_irqrestore(&ichx_priv.lock, flags);
230 return !!((data >> 16) & BIT(nr));
232 return ichx_gpio_get(chip, nr);
236 static int ichx_gpio_request(struct gpio_chip *chip, unsigned nr)
238 if (!ichx_gpio_check_available(chip, nr))
242 * Note we assume the BIOS properly set a bridge's USE value. Some
243 * chips (eg Intel 3100) have bogus USE values though, so first see if
244 * the chipset's USE value can be trusted for this specific bit.
245 * If it can't be trusted, assume that the pin can be used as a GPIO.
247 if (ichx_priv.desc->use_sel_ignore[nr / 32] & BIT(nr & 0x1f))
250 return ichx_read_bit(GPIO_USE_SEL, nr) ? 0 : -ENODEV;
253 static int ich6_gpio_request(struct gpio_chip *chip, unsigned nr)
256 * Fixups for bits 16 and 17 are necessary on the Intel ICH6/3100
257 * bridge as they are controlled by USE register bits 0 and 1. See
258 * "Table 704 GPIO_USE_SEL1 register" in the i3100 datasheet for
261 if (nr == 16 || nr == 17)
264 return ichx_gpio_request(chip, nr);
267 static void ichx_gpio_set(struct gpio_chip *chip, unsigned nr, int val)
269 ichx_write_bit(GPIO_LVL, nr, val, 0);
272 static void ichx_gpiolib_setup(struct gpio_chip *chip)
274 chip->owner = THIS_MODULE;
275 chip->label = DRV_NAME;
276 chip->parent = ichx_priv.dev;
278 /* Allow chip-specific overrides of request()/get() */
279 chip->request = ichx_priv.desc->request ?
280 ichx_priv.desc->request : ichx_gpio_request;
281 chip->get = ichx_priv.desc->get ?
282 ichx_priv.desc->get : ichx_gpio_get;
284 chip->set = ichx_gpio_set;
285 chip->get_direction = ichx_gpio_get_direction;
286 chip->direction_input = ichx_gpio_direction_input;
287 chip->direction_output = ichx_gpio_direction_output;
288 chip->base = modparam_gpiobase;
289 chip->ngpio = ichx_priv.desc->ngpio;
290 chip->can_sleep = false;
291 chip->dbg_show = NULL;
294 /* ICH6-based, 631xesb-based */
295 static struct ichx_desc ich6_desc = {
296 /* Bridges using the ICH6 controller need fixups for GPIO 0 - 17 */
297 .request = ich6_gpio_request,
298 .get = ich6_gpio_get,
300 /* GPIO 0-15 are read in the GPE0_STS PM register */
306 .reglen = ichx_reglen,
310 static struct ichx_desc i3100_desc = {
312 * Bits 16,17, 20 of USE_SEL and bit 16 of USE_SEL2 always read 0 on
313 * the Intel 3100. See "Table 712. GPIO Summary Table" of 3100
314 * Datasheet for more info.
316 .use_sel_ignore = {0x00130000, 0x00010000, 0x0},
318 /* The 3100 needs fixups for GPIO 0 - 17 */
319 .request = ich6_gpio_request,
320 .get = ich6_gpio_get,
322 /* GPIO 0-15 are read in the GPE0_STS PM register */
327 .reglen = ichx_reglen,
330 /* ICH7 and ICH8-based */
331 static struct ichx_desc ich7_desc = {
335 .reglen = ichx_reglen,
339 static struct ichx_desc ich9_desc = {
343 .reglen = ichx_reglen,
346 /* ICH10-based - Consumer/corporate versions have different amount of GPIO */
347 static struct ichx_desc ich10_cons_desc = {
351 .reglen = ichx_reglen,
353 static struct ichx_desc ich10_corp_desc = {
357 .reglen = ichx_reglen,
360 /* Intel 5 series, 6 series, 3400 series, and C200 series */
361 static struct ichx_desc intel5_desc = {
364 .reglen = ichx_reglen,
368 static struct ichx_desc avoton_desc = {
369 /* Avoton has only 59 GPIOs, but we assume the first set of register
370 * (Core) has 32 instead of 31 to keep gpio-ich compliance
374 .reglen = avoton_reglen,
375 .use_outlvl_cache = true,
378 static int ichx_gpio_request_regions(struct device *dev,
379 struct resource *res_base, const char *name, u8 use_gpio)
383 if (!res_base || !res_base->start || !res_base->end)
386 for (i = 0; i < ARRAY_SIZE(ichx_priv.desc->regs[0]); i++) {
387 if (!(use_gpio & BIT(i)))
389 if (!devm_request_region(dev,
390 res_base->start + ichx_priv.desc->regs[0][i],
391 ichx_priv.desc->reglen[i], name))
397 static int ichx_gpio_probe(struct platform_device *pdev)
399 struct device *dev = &pdev->dev;
400 struct lpc_ich_info *ich_info = dev_get_platdata(dev);
401 struct resource *res_base, *res_pm;
407 switch (ich_info->gpio_version) {
409 ichx_priv.desc = &i3100_desc;
412 ichx_priv.desc = &intel5_desc;
415 ichx_priv.desc = &ich6_desc;
418 ichx_priv.desc = &ich7_desc;
421 ichx_priv.desc = &ich9_desc;
423 case ICH_V10CORP_GPIO:
424 ichx_priv.desc = &ich10_corp_desc;
426 case ICH_V10CONS_GPIO:
427 ichx_priv.desc = &ich10_cons_desc;
430 ichx_priv.desc = &avoton_desc;
437 spin_lock_init(&ichx_priv.lock);
439 res_base = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_GPIO);
440 err = ichx_gpio_request_regions(dev, res_base, pdev->name,
445 ichx_priv.gpio_base = res_base;
446 ichx_priv.use_gpio = ich_info->use_gpio;
449 * If necessary, determine the I/O address of ACPI/power management
450 * registers which are needed to read the GPE0 register for GPI pins
451 * 0 - 15 on some chipsets.
453 if (!ichx_priv.desc->uses_gpe0)
456 res_pm = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_GPE0);
458 dev_warn(dev, "ACPI BAR is unavailable, GPI 0 - 15 unavailable\n");
462 if (!devm_request_region(dev, res_pm->start, resource_size(res_pm),
464 dev_warn(dev, "ACPI BAR is busy, GPI 0 - 15 unavailable\n");
468 ichx_priv.pm_base = res_pm;
471 ichx_gpiolib_setup(&ichx_priv.chip);
472 err = gpiochip_add_data(&ichx_priv.chip, NULL);
474 dev_err(dev, "Failed to register GPIOs\n");
478 dev_info(dev, "GPIO from %d to %d\n", ichx_priv.chip.base,
479 ichx_priv.chip.base + ichx_priv.chip.ngpio - 1);
484 static int ichx_gpio_remove(struct platform_device *pdev)
486 gpiochip_remove(&ichx_priv.chip);
491 static struct platform_driver ichx_gpio_driver = {
495 .probe = ichx_gpio_probe,
496 .remove = ichx_gpio_remove,
499 module_platform_driver(ichx_gpio_driver);
501 MODULE_AUTHOR("Peter Tyser <ptyser@xes-inc.com>");
502 MODULE_DESCRIPTION("GPIO interface for Intel ICH series");
503 MODULE_LICENSE("GPL");
504 MODULE_ALIAS("platform:"DRV_NAME);