2 * GPIO controller driver for Intel Lynxpoint PCH chipset>
3 * Copyright (c) 2012, Intel Corporation.
5 * Author: Mathias Nyman <mathias.nyman@linux.intel.com>
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms and conditions of the GNU General Public License,
9 * version 2, as published by the Free Software Foundation.
11 * This program is distributed in the hope it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
16 * You should have received a copy of the GNU General Public License along with
17 * this program; if not, write to the Free Software Foundation, Inc.,
18 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/types.h>
26 #include <linux/bitops.h>
27 #include <linux/interrupt.h>
28 #include <linux/irq.h>
29 #include <linux/gpio.h>
30 #include <linux/irqdomain.h>
31 #include <linux/slab.h>
32 #include <linux/acpi.h>
33 #include <linux/platform_device.h>
34 #include <linux/pm_runtime.h>
37 /* LynxPoint chipset has support for 94 gpio pins */
39 #define LP_NUM_GPIO 94
41 /* Bitmapped register offsets */
42 #define LP_ACPI_OWNED 0x00 /* Bitmap, set by bios, 0: pin reserved for ACPI */
43 #define LP_GC 0x7C /* set APIC IRQ to IRQ14 or IRQ15 for all pins */
44 #define LP_INT_STAT 0x80
45 #define LP_INT_ENABLE 0x90
47 /* Each pin has two 32 bit config registers, starting at 0x100 */
48 #define LP_CONFIG1 0x100
49 #define LP_CONFIG2 0x104
51 /* LP_CONFIG1 reg bits */
52 #define OUT_LVL_BIT BIT(31)
53 #define IN_LVL_BIT BIT(30)
54 #define TRIG_SEL_BIT BIT(4) /* 0: Edge, 1: Level */
55 #define INT_INV_BIT BIT(3) /* Invert interrupt triggering */
56 #define DIR_BIT BIT(2) /* 0: Output, 1: Input */
57 #define USE_SEL_BIT BIT(0) /* 0: Native, 1: GPIO */
59 /* LP_CONFIG2 reg bits */
60 #define GPINDIS_BIT BIT(2) /* disable input sensing */
61 #define GPIWP_BIT (BIT(0) | BIT(1)) /* weak pull options */
64 struct gpio_chip chip
;
65 struct irq_domain
*domain
;
66 struct platform_device
*pdev
;
68 unsigned long reg_base
;
72 * Lynxpoint gpios are controlled through both bitmapped registers and
73 * per gpio specific registers. The bitmapped registers are in chunks of
74 * 3 x 32bit registers to cover all 94 gpios
76 * per gpio specific registers consist of two 32bit registers per gpio
77 * (LP_CONFIG1 and LP_CONFIG2), with 94 gpios there's a total of
78 * 188 config registes.
80 * A simplified view of the register layout look like this:
82 * LP_ACPI_OWNED[31:0] gpio ownerships for gpios 0-31 (bitmapped registers)
83 * LP_ACPI_OWNED[63:32] gpio ownerships for gpios 32-63
84 * LP_ACPI_OWNED[94:64] gpio ownerships for gpios 63-94
86 * LP_INT_ENABLE[31:0] ...
87 * LP_INT_ENABLE[63:31] ...
88 * LP_INT_ENABLE[94:64] ...
89 * LP0_CONFIG1 (gpio 0) config1 reg for gpio 0 (per gpio registers)
90 * LP0_CONFIG2 (gpio 0) config2 reg for gpio 0
91 * LP1_CONFIG1 (gpio 1) config1 reg for gpio 1
92 * LP1_CONFIG2 (gpio 1) config2 reg for gpio 1
93 * LP2_CONFIG1 (gpio 2) ...
94 * LP2_CONFIG2 (gpio 2) ...
96 * LP94_CONFIG1 (gpio 94) ...
97 * LP94_CONFIG2 (gpio 94) ...
100 static unsigned long lp_gpio_reg(struct gpio_chip
*chip
, unsigned offset
,
103 struct lp_gpio
*lg
= container_of(chip
, struct lp_gpio
, chip
);
106 if (reg
== LP_CONFIG1
|| reg
== LP_CONFIG2
)
107 /* per gpio specific config registers */
108 reg_offset
= offset
* 8;
110 /* bitmapped registers */
111 reg_offset
= (offset
/ 32) * 4;
113 return lg
->reg_base
+ reg
+ reg_offset
;
116 static int lp_gpio_request(struct gpio_chip
*chip
, unsigned offset
)
118 struct lp_gpio
*lg
= container_of(chip
, struct lp_gpio
, chip
);
119 unsigned long reg
= lp_gpio_reg(chip
, offset
, LP_CONFIG1
);
120 unsigned long conf2
= lp_gpio_reg(chip
, offset
, LP_CONFIG2
);
121 unsigned long acpi_use
= lp_gpio_reg(chip
, offset
, LP_ACPI_OWNED
);
123 pm_runtime_get(&lg
->pdev
->dev
); /* should we put if failed */
125 /* Fail if BIOS reserved pin for ACPI use */
126 if (!(inl(acpi_use
) & BIT(offset
% 32))) {
127 dev_err(&lg
->pdev
->dev
, "gpio %d reserved for ACPI\n", offset
);
130 /* Fail if pin is in alternate function mode (not GPIO mode) */
131 if (!(inl(reg
) & USE_SEL_BIT
))
134 /* enable input sensing */
135 outl(inl(conf2
) & ~GPINDIS_BIT
, conf2
);
141 static void lp_gpio_free(struct gpio_chip
*chip
, unsigned offset
)
143 struct lp_gpio
*lg
= container_of(chip
, struct lp_gpio
, chip
);
144 unsigned long conf2
= lp_gpio_reg(chip
, offset
, LP_CONFIG2
);
146 /* disable input sensing */
147 outl(inl(conf2
) | GPINDIS_BIT
, conf2
);
149 pm_runtime_put(&lg
->pdev
->dev
);
152 static int lp_irq_type(struct irq_data
*d
, unsigned type
)
154 struct lp_gpio
*lg
= irq_data_get_irq_chip_data(d
);
155 u32 hwirq
= irqd_to_hwirq(d
);
158 unsigned long reg
= lp_gpio_reg(&lg
->chip
, hwirq
, LP_CONFIG1
);
160 if (hwirq
>= lg
->chip
.ngpio
)
163 spin_lock_irqsave(&lg
->lock
, flags
);
166 /* set both TRIG_SEL and INV bits to 0 for rising edge */
167 if (type
& IRQ_TYPE_EDGE_RISING
)
168 value
&= ~(TRIG_SEL_BIT
| INT_INV_BIT
);
170 /* TRIG_SEL bit 0, INV bit 1 for falling edge */
171 if (type
& IRQ_TYPE_EDGE_FALLING
)
172 value
= (value
| INT_INV_BIT
) & ~TRIG_SEL_BIT
;
174 /* TRIG_SEL bit 1, INV bit 0 for level low */
175 if (type
& IRQ_TYPE_LEVEL_LOW
)
176 value
= (value
| TRIG_SEL_BIT
) & ~INT_INV_BIT
;
178 /* TRIG_SEL bit 1, INV bit 1 for level high */
179 if (type
& IRQ_TYPE_LEVEL_HIGH
)
180 value
|= TRIG_SEL_BIT
| INT_INV_BIT
;
183 spin_unlock_irqrestore(&lg
->lock
, flags
);
188 static int lp_gpio_get(struct gpio_chip
*chip
, unsigned offset
)
190 unsigned long reg
= lp_gpio_reg(chip
, offset
, LP_CONFIG1
);
191 return inl(reg
) & IN_LVL_BIT
;
194 static void lp_gpio_set(struct gpio_chip
*chip
, unsigned offset
, int value
)
196 struct lp_gpio
*lg
= container_of(chip
, struct lp_gpio
, chip
);
197 unsigned long reg
= lp_gpio_reg(chip
, offset
, LP_CONFIG1
);
200 spin_lock_irqsave(&lg
->lock
, flags
);
203 outl(inl(reg
) | OUT_LVL_BIT
, reg
);
205 outl(inl(reg
) & ~OUT_LVL_BIT
, reg
);
207 spin_unlock_irqrestore(&lg
->lock
, flags
);
210 static int lp_gpio_direction_input(struct gpio_chip
*chip
, unsigned offset
)
212 struct lp_gpio
*lg
= container_of(chip
, struct lp_gpio
, chip
);
213 unsigned long reg
= lp_gpio_reg(chip
, offset
, LP_CONFIG1
);
216 spin_lock_irqsave(&lg
->lock
, flags
);
217 outl(inl(reg
) | DIR_BIT
, reg
);
218 spin_unlock_irqrestore(&lg
->lock
, flags
);
223 static int lp_gpio_direction_output(struct gpio_chip
*chip
,
224 unsigned offset
, int value
)
226 struct lp_gpio
*lg
= container_of(chip
, struct lp_gpio
, chip
);
227 unsigned long reg
= lp_gpio_reg(chip
, offset
, LP_CONFIG1
);
230 lp_gpio_set(chip
, offset
, value
);
232 spin_lock_irqsave(&lg
->lock
, flags
);
233 outl(inl(reg
) & ~DIR_BIT
, reg
);
234 spin_unlock_irqrestore(&lg
->lock
, flags
);
239 static int lp_gpio_to_irq(struct gpio_chip
*chip
, unsigned offset
)
241 struct lp_gpio
*lg
= container_of(chip
, struct lp_gpio
, chip
);
242 return irq_create_mapping(lg
->domain
, offset
);
245 static void lp_gpio_irq_handler(unsigned irq
, struct irq_desc
*desc
)
247 struct irq_data
*data
= irq_desc_get_irq_data(desc
);
248 struct lp_gpio
*lg
= irq_data_get_irq_handler_data(data
);
249 struct irq_chip
*chip
= irq_data_get_irq_chip(data
);
251 unsigned long reg
, ena
, pending
;
254 /* check from GPIO controller which pin triggered the interrupt */
255 for (base
= 0; base
< lg
->chip
.ngpio
; base
+= 32) {
256 reg
= lp_gpio_reg(&lg
->chip
, base
, LP_INT_STAT
);
257 ena
= lp_gpio_reg(&lg
->chip
, base
, LP_INT_ENABLE
);
259 while ((pending
= (inl(reg
) & inl(ena
)))) {
260 pin
= __ffs(pending
);
262 /* Clear before handling so we don't lose an edge */
264 virq
= irq_find_mapping(lg
->domain
, base
+ pin
);
265 generic_handle_irq(virq
);
271 static void lp_irq_unmask(struct irq_data
*d
)
275 static void lp_irq_mask(struct irq_data
*d
)
279 static void lp_irq_enable(struct irq_data
*d
)
281 struct lp_gpio
*lg
= irq_data_get_irq_chip_data(d
);
282 u32 hwirq
= irqd_to_hwirq(d
);
283 unsigned long reg
= lp_gpio_reg(&lg
->chip
, hwirq
, LP_INT_ENABLE
);
286 spin_lock_irqsave(&lg
->lock
, flags
);
287 outl(inl(reg
) | BIT(hwirq
% 32), reg
);
288 spin_unlock_irqrestore(&lg
->lock
, flags
);
291 static void lp_irq_disable(struct irq_data
*d
)
293 struct lp_gpio
*lg
= irq_data_get_irq_chip_data(d
);
294 u32 hwirq
= irqd_to_hwirq(d
);
295 unsigned long reg
= lp_gpio_reg(&lg
->chip
, hwirq
, LP_INT_ENABLE
);
298 spin_lock_irqsave(&lg
->lock
, flags
);
299 outl(inl(reg
) & ~BIT(hwirq
% 32), reg
);
300 spin_unlock_irqrestore(&lg
->lock
, flags
);
303 static struct irq_chip lp_irqchip
= {
305 .irq_mask
= lp_irq_mask
,
306 .irq_unmask
= lp_irq_unmask
,
307 .irq_enable
= lp_irq_enable
,
308 .irq_disable
= lp_irq_disable
,
309 .irq_set_type
= lp_irq_type
,
310 .flags
= IRQCHIP_SKIP_SET_WAKE
,
313 static void lp_gpio_irq_init_hw(struct lp_gpio
*lg
)
318 for (base
= 0; base
< lg
->chip
.ngpio
; base
+= 32) {
319 /* disable gpio pin interrupts */
320 reg
= lp_gpio_reg(&lg
->chip
, base
, LP_INT_ENABLE
);
322 /* Clear interrupt status register */
323 reg
= lp_gpio_reg(&lg
->chip
, base
, LP_INT_STAT
);
324 outl(0xffffffff, reg
);
328 static int lp_gpio_irq_map(struct irq_domain
*d
, unsigned int virq
,
331 struct lp_gpio
*lg
= d
->host_data
;
333 irq_set_chip_and_handler_name(virq
, &lp_irqchip
, handle_simple_irq
,
335 irq_set_chip_data(virq
, lg
);
336 irq_set_irq_type(virq
, IRQ_TYPE_NONE
);
341 static const struct irq_domain_ops lp_gpio_irq_ops
= {
342 .map
= lp_gpio_irq_map
,
345 static int lp_gpio_probe(struct platform_device
*pdev
)
348 struct gpio_chip
*gc
;
349 struct resource
*io_rc
, *irq_rc
;
350 struct device
*dev
= &pdev
->dev
;
351 unsigned long reg_len
;
355 lg
= devm_kzalloc(dev
, sizeof(struct lp_gpio
), GFP_KERNEL
);
357 dev_err(dev
, "can't allocate lp_gpio chip data\n");
362 platform_set_drvdata(pdev
, lg
);
364 io_rc
= platform_get_resource(pdev
, IORESOURCE_IO
, 0);
365 irq_rc
= platform_get_resource(pdev
, IORESOURCE_IRQ
, 0);
368 dev_err(dev
, "missing IO resources\n");
372 lg
->reg_base
= io_rc
->start
;
373 reg_len
= resource_size(io_rc
);
375 if (!devm_request_region(dev
, lg
->reg_base
, reg_len
, "lp-gpio")) {
376 dev_err(dev
, "failed requesting IO region 0x%x\n",
377 (unsigned int)lg
->reg_base
);
381 spin_lock_init(&lg
->lock
);
384 gc
->label
= dev_name(dev
);
385 gc
->owner
= THIS_MODULE
;
386 gc
->request
= lp_gpio_request
;
387 gc
->free
= lp_gpio_free
;
388 gc
->direction_input
= lp_gpio_direction_input
;
389 gc
->direction_output
= lp_gpio_direction_output
;
390 gc
->get
= lp_gpio_get
;
391 gc
->set
= lp_gpio_set
;
393 gc
->ngpio
= LP_NUM_GPIO
;
397 /* set up interrupts */
398 if (irq_rc
&& irq_rc
->start
) {
399 hwirq
= irq_rc
->start
;
400 gc
->to_irq
= lp_gpio_to_irq
;
402 lg
->domain
= irq_domain_add_linear(NULL
, LP_NUM_GPIO
,
403 &lp_gpio_irq_ops
, lg
);
407 lp_gpio_irq_init_hw(lg
);
409 irq_set_handler_data(hwirq
, lg
);
410 irq_set_chained_handler(hwirq
, lp_gpio_irq_handler
);
413 ret
= gpiochip_add(gc
);
415 dev_err(dev
, "failed adding lp-gpio chip\n");
418 pm_runtime_enable(dev
);
423 static int lp_gpio_runtime_suspend(struct device
*dev
)
428 static int lp_gpio_runtime_resume(struct device
*dev
)
433 static const struct dev_pm_ops lp_gpio_pm_ops
= {
434 .runtime_suspend
= lp_gpio_runtime_suspend
,
435 .runtime_resume
= lp_gpio_runtime_resume
,
438 static const struct acpi_device_id lynxpoint_gpio_acpi_match
[] = {
442 MODULE_DEVICE_TABLE(acpi
, lynxpoint_gpio_acpi_match
);
444 static int lp_gpio_remove(struct platform_device
*pdev
)
446 struct lp_gpio
*lg
= platform_get_drvdata(pdev
);
448 pm_runtime_disable(&pdev
->dev
);
449 err
= gpiochip_remove(&lg
->chip
);
451 dev_warn(&pdev
->dev
, "failed to remove gpio_chip.\n");
455 static struct platform_driver lp_gpio_driver
= {
456 .probe
= lp_gpio_probe
,
457 .remove
= lp_gpio_remove
,
460 .owner
= THIS_MODULE
,
461 .pm
= &lp_gpio_pm_ops
,
462 .acpi_match_table
= ACPI_PTR(lynxpoint_gpio_acpi_match
),
466 static int __init
lp_gpio_init(void)
468 return platform_driver_register(&lp_gpio_driver
);
471 subsys_initcall(lp_gpio_init
);