2 * Generic GPIO driver for logic cells found in the Nomadik SoC
4 * Copyright (C) 2008,2009 STMicroelectronics
5 * Copyright (C) 2009 Alessandro Rubini <rubini@unipv.it>
6 * Rewritten based on work by Prafulla WADASKAR <prafulla.wadaskar@st.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/device.h>
16 #include <linux/platform_device.h>
18 #include <linux/clk.h>
19 #include <linux/err.h>
20 #include <linux/gpio.h>
21 #include <linux/spinlock.h>
22 #include <linux/interrupt.h>
23 #include <linux/irq.h>
24 #include <linux/slab.h>
26 #include <plat/pincfg.h>
27 #include <mach/hardware.h>
28 #include <mach/gpio.h>
31 * The GPIO module in the Nomadik family of Systems-on-Chip is an
32 * AMBA device, managing 32 pins and alternate functions. The logic block
33 * is currently only used in the Nomadik.
35 * Symbols in this file are called "nmk_gpio" for "nomadik gpio"
38 #define NMK_GPIO_PER_CHIP 32
39 struct nmk_gpio_chip
{
40 struct gpio_chip chip
;
43 unsigned int parent_irq
;
45 /* Keep track of configured edges */
50 static void __nmk_gpio_set_mode(struct nmk_gpio_chip
*nmk_chip
,
51 unsigned offset
, int gpio_mode
)
53 u32 bit
= 1 << offset
;
56 afunc
= readl(nmk_chip
->addr
+ NMK_GPIO_AFSLA
) & ~bit
;
57 bfunc
= readl(nmk_chip
->addr
+ NMK_GPIO_AFSLB
) & ~bit
;
58 if (gpio_mode
& NMK_GPIO_ALT_A
)
60 if (gpio_mode
& NMK_GPIO_ALT_B
)
62 writel(afunc
, nmk_chip
->addr
+ NMK_GPIO_AFSLA
);
63 writel(bfunc
, nmk_chip
->addr
+ NMK_GPIO_AFSLB
);
66 static void __nmk_gpio_set_slpm(struct nmk_gpio_chip
*nmk_chip
,
67 unsigned offset
, enum nmk_gpio_slpm mode
)
69 u32 bit
= 1 << offset
;
72 slpm
= readl(nmk_chip
->addr
+ NMK_GPIO_SLPC
);
73 if (mode
== NMK_GPIO_SLPM_NOCHANGE
)
77 writel(slpm
, nmk_chip
->addr
+ NMK_GPIO_SLPC
);
80 static void __nmk_gpio_set_pull(struct nmk_gpio_chip
*nmk_chip
,
81 unsigned offset
, enum nmk_gpio_pull pull
)
83 u32 bit
= 1 << offset
;
86 pdis
= readl(nmk_chip
->addr
+ NMK_GPIO_PDIS
);
87 if (pull
== NMK_GPIO_PULL_NONE
)
91 writel(pdis
, nmk_chip
->addr
+ NMK_GPIO_PDIS
);
93 if (pull
== NMK_GPIO_PULL_UP
)
94 writel(bit
, nmk_chip
->addr
+ NMK_GPIO_DATS
);
95 else if (pull
== NMK_GPIO_PULL_DOWN
)
96 writel(bit
, nmk_chip
->addr
+ NMK_GPIO_DATC
);
99 static void __nmk_gpio_make_input(struct nmk_gpio_chip
*nmk_chip
,
102 writel(1 << offset
, nmk_chip
->addr
+ NMK_GPIO_DIRC
);
105 static void __nmk_config_pin(struct nmk_gpio_chip
*nmk_chip
, unsigned offset
,
108 static const char *afnames
[] = {
109 [NMK_GPIO_ALT_GPIO
] = "GPIO",
110 [NMK_GPIO_ALT_A
] = "A",
111 [NMK_GPIO_ALT_B
] = "B",
112 [NMK_GPIO_ALT_C
] = "C"
114 static const char *pullnames
[] = {
115 [NMK_GPIO_PULL_NONE
] = "none",
116 [NMK_GPIO_PULL_UP
] = "up",
117 [NMK_GPIO_PULL_DOWN
] = "down",
118 [3] /* illegal */ = "??"
120 static const char *slpmnames
[] = {
121 [NMK_GPIO_SLPM_INPUT
] = "input",
122 [NMK_GPIO_SLPM_NOCHANGE
] = "no-change",
125 int pin
= PIN_NUM(cfg
);
126 int pull
= PIN_PULL(cfg
);
127 int af
= PIN_ALT(cfg
);
128 int slpm
= PIN_SLPM(cfg
);
130 dev_dbg(nmk_chip
->chip
.dev
, "pin %d: af %s, pull %s, slpm %s\n",
131 pin
, afnames
[af
], pullnames
[pull
], slpmnames
[slpm
]);
133 __nmk_gpio_make_input(nmk_chip
, offset
);
134 __nmk_gpio_set_pull(nmk_chip
, offset
, pull
);
135 __nmk_gpio_set_slpm(nmk_chip
, offset
, slpm
);
136 __nmk_gpio_set_mode(nmk_chip
, offset
, af
);
140 * nmk_config_pin - configure a pin's mux attributes
141 * @cfg: pin confguration
143 * Configures a pin's mode (alternate function or GPIO), its pull up status,
144 * and its sleep mode based on the specified configuration. The @cfg is
145 * usually one of the SoC specific macros defined in mach/<soc>-pins.h. These
146 * are constructed using, and can be further enhanced with, the macros in
149 * If a pin's mode is set to GPIO, it is configured as an input to avoid
150 * side-effects. The gpio can be manipulated later using standard GPIO API
153 int nmk_config_pin(pin_cfg_t cfg
)
155 struct nmk_gpio_chip
*nmk_chip
;
156 int gpio
= PIN_NUM(cfg
);
159 nmk_chip
= get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio
));
163 spin_lock_irqsave(&nmk_chip
->lock
, flags
);
164 __nmk_config_pin(nmk_chip
, gpio
- nmk_chip
->chip
.base
, cfg
);
165 spin_unlock_irqrestore(&nmk_chip
->lock
, flags
);
169 EXPORT_SYMBOL(nmk_config_pin
);
172 * nmk_config_pins - configure several pins at once
173 * @cfgs: array of pin configurations
174 * @num: number of elments in the array
176 * Configures several pins using nmk_config_pin(). Refer to that function for
177 * further information.
179 int nmk_config_pins(pin_cfg_t
*cfgs
, int num
)
184 for (i
= 0; i
< num
; i
++) {
185 int ret
= nmk_config_pin(cfgs
[i
]);
192 EXPORT_SYMBOL(nmk_config_pins
);
195 * nmk_gpio_set_slpm() - configure the sleep mode of a pin
197 * @mode: NMK_GPIO_SLPM_INPUT or NMK_GPIO_SLPM_NOCHANGE,
199 * Sets the sleep mode of a pin. If @mode is NMK_GPIO_SLPM_INPUT, the pin is
200 * changed to an input (with pullup/down enabled) in sleep and deep sleep. If
201 * @mode is NMK_GPIO_SLPM_NOCHANGE, the pin remains in the state it was
202 * configured even when in sleep and deep sleep.
204 int nmk_gpio_set_slpm(int gpio
, enum nmk_gpio_slpm mode
)
206 struct nmk_gpio_chip
*nmk_chip
;
209 nmk_chip
= get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio
));
213 spin_lock_irqsave(&nmk_chip
->lock
, flags
);
214 __nmk_gpio_set_slpm(nmk_chip
, gpio
- nmk_chip
->chip
.base
, mode
);
215 spin_unlock_irqrestore(&nmk_chip
->lock
, flags
);
221 * nmk_gpio_set_pull() - enable/disable pull up/down on a gpio
223 * @pull: one of NMK_GPIO_PULL_DOWN, NMK_GPIO_PULL_UP, and NMK_GPIO_PULL_NONE
225 * Enables/disables pull up/down on a specified pin. This only takes effect if
226 * the pin is configured as an input (either explicitly or by the alternate
229 * NOTE: If enabling the pull up/down, the caller must ensure that the GPIO is
230 * configured as an input. Otherwise, due to the way the controller registers
231 * work, this function will change the value output on the pin.
233 int nmk_gpio_set_pull(int gpio
, enum nmk_gpio_pull pull
)
235 struct nmk_gpio_chip
*nmk_chip
;
238 nmk_chip
= get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio
));
242 spin_lock_irqsave(&nmk_chip
->lock
, flags
);
243 __nmk_gpio_set_pull(nmk_chip
, gpio
- nmk_chip
->chip
.base
, pull
);
244 spin_unlock_irqrestore(&nmk_chip
->lock
, flags
);
250 int nmk_gpio_set_mode(int gpio
, int gpio_mode
)
252 struct nmk_gpio_chip
*nmk_chip
;
255 nmk_chip
= get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio
));
259 spin_lock_irqsave(&nmk_chip
->lock
, flags
);
260 __nmk_gpio_set_mode(nmk_chip
, gpio
- nmk_chip
->chip
.base
, gpio_mode
);
261 spin_unlock_irqrestore(&nmk_chip
->lock
, flags
);
265 EXPORT_SYMBOL(nmk_gpio_set_mode
);
267 int nmk_gpio_get_mode(int gpio
)
269 struct nmk_gpio_chip
*nmk_chip
;
270 u32 afunc
, bfunc
, bit
;
272 nmk_chip
= get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio
));
276 bit
= 1 << (gpio
- nmk_chip
->chip
.base
);
278 afunc
= readl(nmk_chip
->addr
+ NMK_GPIO_AFSLA
) & bit
;
279 bfunc
= readl(nmk_chip
->addr
+ NMK_GPIO_AFSLB
) & bit
;
281 return (afunc
? NMK_GPIO_ALT_A
: 0) | (bfunc
? NMK_GPIO_ALT_B
: 0);
283 EXPORT_SYMBOL(nmk_gpio_get_mode
);
287 static inline int nmk_gpio_get_bitmask(int gpio
)
289 return 1 << (gpio
% 32);
292 static void nmk_gpio_irq_ack(unsigned int irq
)
295 struct nmk_gpio_chip
*nmk_chip
;
297 gpio
= NOMADIK_IRQ_TO_GPIO(irq
);
298 nmk_chip
= get_irq_chip_data(irq
);
301 writel(nmk_gpio_get_bitmask(gpio
), nmk_chip
->addr
+ NMK_GPIO_IC
);
304 enum nmk_gpio_irq_type
{
309 static void __nmk_gpio_irq_modify(struct nmk_gpio_chip
*nmk_chip
,
310 int gpio
, enum nmk_gpio_irq_type which
,
313 u32 rimsc
= which
== WAKE
? NMK_GPIO_RWIMSC
: NMK_GPIO_RIMSC
;
314 u32 fimsc
= which
== WAKE
? NMK_GPIO_FWIMSC
: NMK_GPIO_FIMSC
;
315 u32 bitmask
= nmk_gpio_get_bitmask(gpio
);
318 /* we must individually set/clear the two edges */
319 if (nmk_chip
->edge_rising
& bitmask
) {
320 reg
= readl(nmk_chip
->addr
+ rimsc
);
325 writel(reg
, nmk_chip
->addr
+ rimsc
);
327 if (nmk_chip
->edge_falling
& bitmask
) {
328 reg
= readl(nmk_chip
->addr
+ fimsc
);
333 writel(reg
, nmk_chip
->addr
+ fimsc
);
337 static int nmk_gpio_irq_modify(unsigned int irq
, enum nmk_gpio_irq_type which
,
341 struct nmk_gpio_chip
*nmk_chip
;
345 gpio
= NOMADIK_IRQ_TO_GPIO(irq
);
346 nmk_chip
= get_irq_chip_data(irq
);
347 bitmask
= nmk_gpio_get_bitmask(gpio
);
351 spin_lock_irqsave(&nmk_chip
->lock
, flags
);
352 __nmk_gpio_irq_modify(nmk_chip
, gpio
, which
, enable
);
353 spin_unlock_irqrestore(&nmk_chip
->lock
, flags
);
358 static void nmk_gpio_irq_mask(unsigned int irq
)
360 nmk_gpio_irq_modify(irq
, NORMAL
, false);
363 static void nmk_gpio_irq_unmask(unsigned int irq
)
365 nmk_gpio_irq_modify(irq
, NORMAL
, true);
368 static int nmk_gpio_irq_set_wake(unsigned int irq
, unsigned int on
)
370 return nmk_gpio_irq_modify(irq
, WAKE
, on
);
373 static int nmk_gpio_irq_set_type(unsigned int irq
, unsigned int type
)
375 struct irq_desc
*desc
= irq_to_desc(irq
);
376 bool enabled
= !(desc
->status
& IRQ_DISABLED
);
377 bool wake
= desc
->wake_depth
;
379 struct nmk_gpio_chip
*nmk_chip
;
383 gpio
= NOMADIK_IRQ_TO_GPIO(irq
);
384 nmk_chip
= get_irq_chip_data(irq
);
385 bitmask
= nmk_gpio_get_bitmask(gpio
);
389 if (type
& IRQ_TYPE_LEVEL_HIGH
)
391 if (type
& IRQ_TYPE_LEVEL_LOW
)
394 spin_lock_irqsave(&nmk_chip
->lock
, flags
);
397 __nmk_gpio_irq_modify(nmk_chip
, gpio
, NORMAL
, false);
400 __nmk_gpio_irq_modify(nmk_chip
, gpio
, WAKE
, false);
402 nmk_chip
->edge_rising
&= ~bitmask
;
403 if (type
& IRQ_TYPE_EDGE_RISING
)
404 nmk_chip
->edge_rising
|= bitmask
;
406 nmk_chip
->edge_falling
&= ~bitmask
;
407 if (type
& IRQ_TYPE_EDGE_FALLING
)
408 nmk_chip
->edge_falling
|= bitmask
;
411 __nmk_gpio_irq_modify(nmk_chip
, gpio
, NORMAL
, true);
414 __nmk_gpio_irq_modify(nmk_chip
, gpio
, WAKE
, true);
416 spin_unlock_irqrestore(&nmk_chip
->lock
, flags
);
421 static struct irq_chip nmk_gpio_irq_chip
= {
422 .name
= "Nomadik-GPIO",
423 .ack
= nmk_gpio_irq_ack
,
424 .mask
= nmk_gpio_irq_mask
,
425 .unmask
= nmk_gpio_irq_unmask
,
426 .set_type
= nmk_gpio_irq_set_type
,
427 .set_wake
= nmk_gpio_irq_set_wake
,
430 static void nmk_gpio_irq_handler(unsigned int irq
, struct irq_desc
*desc
)
432 struct nmk_gpio_chip
*nmk_chip
;
433 struct irq_chip
*host_chip
= get_irq_chip(irq
);
434 unsigned int gpio_irq
;
436 unsigned int first_irq
;
438 if (host_chip
->mask_ack
)
439 host_chip
->mask_ack(irq
);
441 host_chip
->mask(irq
);
446 nmk_chip
= get_irq_data(irq
);
447 first_irq
= NOMADIK_GPIO_TO_IRQ(nmk_chip
->chip
.base
);
448 while ( (pending
= readl(nmk_chip
->addr
+ NMK_GPIO_IS
)) ) {
449 gpio_irq
= first_irq
+ __ffs(pending
);
450 generic_handle_irq(gpio_irq
);
453 host_chip
->unmask(irq
);
456 static int nmk_gpio_init_irq(struct nmk_gpio_chip
*nmk_chip
)
458 unsigned int first_irq
;
461 first_irq
= NOMADIK_GPIO_TO_IRQ(nmk_chip
->chip
.base
);
462 for (i
= first_irq
; i
< first_irq
+ NMK_GPIO_PER_CHIP
; i
++) {
463 set_irq_chip(i
, &nmk_gpio_irq_chip
);
464 set_irq_handler(i
, handle_edge_irq
);
465 set_irq_flags(i
, IRQF_VALID
);
466 set_irq_chip_data(i
, nmk_chip
);
467 set_irq_type(i
, IRQ_TYPE_EDGE_FALLING
);
469 set_irq_chained_handler(nmk_chip
->parent_irq
, nmk_gpio_irq_handler
);
470 set_irq_data(nmk_chip
->parent_irq
, nmk_chip
);
475 static int nmk_gpio_make_input(struct gpio_chip
*chip
, unsigned offset
)
477 struct nmk_gpio_chip
*nmk_chip
=
478 container_of(chip
, struct nmk_gpio_chip
, chip
);
480 writel(1 << offset
, nmk_chip
->addr
+ NMK_GPIO_DIRC
);
484 static int nmk_gpio_get_input(struct gpio_chip
*chip
, unsigned offset
)
486 struct nmk_gpio_chip
*nmk_chip
=
487 container_of(chip
, struct nmk_gpio_chip
, chip
);
488 u32 bit
= 1 << offset
;
490 return (readl(nmk_chip
->addr
+ NMK_GPIO_DAT
) & bit
) != 0;
493 static void nmk_gpio_set_output(struct gpio_chip
*chip
, unsigned offset
,
496 struct nmk_gpio_chip
*nmk_chip
=
497 container_of(chip
, struct nmk_gpio_chip
, chip
);
498 u32 bit
= 1 << offset
;
501 writel(bit
, nmk_chip
->addr
+ NMK_GPIO_DATS
);
503 writel(bit
, nmk_chip
->addr
+ NMK_GPIO_DATC
);
506 static int nmk_gpio_make_output(struct gpio_chip
*chip
, unsigned offset
,
509 struct nmk_gpio_chip
*nmk_chip
=
510 container_of(chip
, struct nmk_gpio_chip
, chip
);
512 writel(1 << offset
, nmk_chip
->addr
+ NMK_GPIO_DIRS
);
513 nmk_gpio_set_output(chip
, offset
, val
);
518 static int nmk_gpio_to_irq(struct gpio_chip
*chip
, unsigned offset
)
520 struct nmk_gpio_chip
*nmk_chip
=
521 container_of(chip
, struct nmk_gpio_chip
, chip
);
523 return NOMADIK_GPIO_TO_IRQ(nmk_chip
->chip
.base
) + offset
;
526 /* This structure is replicated for each GPIO block allocated at probe time */
527 static struct gpio_chip nmk_gpio_template
= {
528 .direction_input
= nmk_gpio_make_input
,
529 .get
= nmk_gpio_get_input
,
530 .direction_output
= nmk_gpio_make_output
,
531 .set
= nmk_gpio_set_output
,
532 .to_irq
= nmk_gpio_to_irq
,
533 .ngpio
= NMK_GPIO_PER_CHIP
,
537 static int __init
nmk_gpio_probe(struct platform_device
*dev
)
539 struct nmk_gpio_platform_data
*pdata
= dev
->dev
.platform_data
;
540 struct nmk_gpio_chip
*nmk_chip
;
541 struct gpio_chip
*chip
;
542 struct resource
*res
;
550 res
= platform_get_resource(dev
, IORESOURCE_MEM
, 0);
556 irq
= platform_get_irq(dev
, 0);
562 if (request_mem_region(res
->start
, resource_size(res
),
563 dev_name(&dev
->dev
)) == NULL
) {
568 clk
= clk_get(&dev
->dev
, NULL
);
576 nmk_chip
= kzalloc(sizeof(*nmk_chip
), GFP_KERNEL
);
582 * The virt address in nmk_chip->addr is in the nomadik register space,
583 * so we can simply convert the resource address, without remapping
586 nmk_chip
->addr
= io_p2v(res
->start
);
587 nmk_chip
->chip
= nmk_gpio_template
;
588 nmk_chip
->parent_irq
= irq
;
589 spin_lock_init(&nmk_chip
->lock
);
591 chip
= &nmk_chip
->chip
;
592 chip
->base
= pdata
->first_gpio
;
593 chip
->label
= pdata
->name
;
594 chip
->dev
= &dev
->dev
;
595 chip
->owner
= THIS_MODULE
;
597 ret
= gpiochip_add(&nmk_chip
->chip
);
601 platform_set_drvdata(dev
, nmk_chip
);
603 nmk_gpio_init_irq(nmk_chip
);
605 dev_info(&dev
->dev
, "Bits %i-%i at address %p\n",
606 nmk_chip
->chip
.base
, nmk_chip
->chip
.base
+31, nmk_chip
->addr
);
615 release_mem_region(res
->start
, resource_size(res
));
617 dev_err(&dev
->dev
, "Failure %i for GPIO %i-%i\n", ret
,
618 pdata
->first_gpio
, pdata
->first_gpio
+31);
622 static struct platform_driver nmk_gpio_driver
= {
624 .owner
= THIS_MODULE
,
627 .probe
= nmk_gpio_probe
,
628 .suspend
= NULL
, /* to be done */
632 static int __init
nmk_gpio_init(void)
634 return platform_driver_register(&nmk_gpio_driver
);
637 core_initcall(nmk_gpio_init
);
639 MODULE_AUTHOR("Prafulla WADASKAR and Alessandro Rubini");
640 MODULE_DESCRIPTION("Nomadik GPIO Driver");
641 MODULE_LICENSE("GPL");