1 /*
2  * MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
3  * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
4  *
5  * Based on code from Freescale,
6  * Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * as published by the Free Software Foundation; either version 2
11  * of the License, or (at your option) any later version.
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
20  * MA  02110-1301, USA.
21  */
22 
23 #include <linux/init.h>
24 #include <linux/interrupt.h>
25 #include <linux/io.h>
26 #include <linux/irq.h>
27 #include <linux/gpio.h>
28 #include <mach/mx23.h>
29 #include <mach/mx28.h>
30 #include <asm-generic/bug.h>
31 
32 #include "gpio.h"
33 
34 static struct mxs_gpio_port *mxs_gpio_ports;
35 static int gpio_table_size;
36 
37 #define PINCTRL_DOUT(n)		((cpu_is_mx23() ? 0x0500 : 0x0700) + (n) * 0x10)
38 #define PINCTRL_DIN(n)		((cpu_is_mx23() ? 0x0600 : 0x0900) + (n) * 0x10)
39 #define PINCTRL_DOE(n)		((cpu_is_mx23() ? 0x0700 : 0x0b00) + (n) * 0x10)
40 #define PINCTRL_PIN2IRQ(n)	((cpu_is_mx23() ? 0x0800 : 0x1000) + (n) * 0x10)
41 #define PINCTRL_IRQEN(n)	((cpu_is_mx23() ? 0x0900 : 0x1100) + (n) * 0x10)
42 #define PINCTRL_IRQLEV(n)	((cpu_is_mx23() ? 0x0a00 : 0x1200) + (n) * 0x10)
43 #define PINCTRL_IRQPOL(n)	((cpu_is_mx23() ? 0x0b00 : 0x1300) + (n) * 0x10)
44 #define PINCTRL_IRQSTAT(n)	((cpu_is_mx23() ? 0x0c00 : 0x1400) + (n) * 0x10)
45 
46 #define GPIO_INT_FALL_EDGE	0x0
47 #define GPIO_INT_LOW_LEV	0x1
48 #define GPIO_INT_RISE_EDGE	0x2
49 #define GPIO_INT_HIGH_LEV	0x3
50 #define GPIO_INT_LEV_MASK	(1 << 0)
51 #define GPIO_INT_POL_MASK	(1 << 1)
52 
53 /* Note: This driver assumes 32 GPIOs are handled in one register */
54 
clear_gpio_irqstatus(struct mxs_gpio_port * port,u32 index)55 static void clear_gpio_irqstatus(struct mxs_gpio_port *port, u32 index)
56 {
57 	__mxs_clrl(1 << index, port->base + PINCTRL_IRQSTAT(port->id));
58 }
59 
set_gpio_irqenable(struct mxs_gpio_port * port,u32 index,int enable)60 static void set_gpio_irqenable(struct mxs_gpio_port *port, u32 index,
61 				int enable)
62 {
63 	if (enable) {
64 		__mxs_setl(1 << index, port->base + PINCTRL_IRQEN(port->id));
65 		__mxs_setl(1 << index, port->base + PINCTRL_PIN2IRQ(port->id));
66 	} else {
67 		__mxs_clrl(1 << index, port->base + PINCTRL_IRQEN(port->id));
68 	}
69 }
70 
mxs_gpio_ack_irq(struct irq_data * d)71 static void mxs_gpio_ack_irq(struct irq_data *d)
72 {
73 	u32 gpio = irq_to_gpio(d->irq);
74 	clear_gpio_irqstatus(&mxs_gpio_ports[gpio / 32], gpio & 0x1f);
75 }
76 
mxs_gpio_mask_irq(struct irq_data * d)77 static void mxs_gpio_mask_irq(struct irq_data *d)
78 {
79 	u32 gpio = irq_to_gpio(d->irq);
80 	set_gpio_irqenable(&mxs_gpio_ports[gpio / 32], gpio & 0x1f, 0);
81 }
82 
mxs_gpio_unmask_irq(struct irq_data * d)83 static void mxs_gpio_unmask_irq(struct irq_data *d)
84 {
85 	u32 gpio = irq_to_gpio(d->irq);
86 	set_gpio_irqenable(&mxs_gpio_ports[gpio / 32], gpio & 0x1f, 1);
87 }
88 
89 static int mxs_gpio_get(struct gpio_chip *chip, unsigned offset);
90 
mxs_gpio_set_irq_type(struct irq_data * d,unsigned int type)91 static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
92 {
93 	u32 gpio = irq_to_gpio(d->irq);
94 	u32 pin_mask = 1 << (gpio & 31);
95 	struct mxs_gpio_port *port = &mxs_gpio_ports[gpio / 32];
96 	void __iomem *pin_addr;
97 	int edge;
98 
99 	switch (type) {
100 	case IRQ_TYPE_EDGE_RISING:
101 		edge = GPIO_INT_RISE_EDGE;
102 		break;
103 	case IRQ_TYPE_EDGE_FALLING:
104 		edge = GPIO_INT_FALL_EDGE;
105 		break;
106 	case IRQ_TYPE_LEVEL_LOW:
107 		edge = GPIO_INT_LOW_LEV;
108 		break;
109 	case IRQ_TYPE_LEVEL_HIGH:
110 		edge = GPIO_INT_HIGH_LEV;
111 		break;
112 	default:
113 		return -EINVAL;
114 	}
115 
116 	/* set level or edge */
117 	pin_addr = port->base + PINCTRL_IRQLEV(port->id);
118 	if (edge & GPIO_INT_LEV_MASK)
119 		__mxs_setl(pin_mask, pin_addr);
120 	else
121 		__mxs_clrl(pin_mask, pin_addr);
122 
123 	/* set polarity */
124 	pin_addr = port->base + PINCTRL_IRQPOL(port->id);
125 	if (edge & GPIO_INT_POL_MASK)
126 		__mxs_setl(pin_mask, pin_addr);
127 	else
128 		__mxs_clrl(pin_mask, pin_addr);
129 
130 	clear_gpio_irqstatus(port, gpio & 0x1f);
131 
132 	return 0;
133 }
134 
135 /* MXS has one interrupt *per* gpio port */
mxs_gpio_irq_handler(u32 irq,struct irq_desc * desc)136 static void mxs_gpio_irq_handler(u32 irq, struct irq_desc *desc)
137 {
138 	u32 irq_stat;
139 	struct mxs_gpio_port *port = (struct mxs_gpio_port *)irq_get_handler_data(irq);
140 	u32 gpio_irq_no_base = port->virtual_irq_start;
141 
142 	desc->irq_data.chip->irq_ack(&desc->irq_data);
143 
144 	irq_stat = __raw_readl(port->base + PINCTRL_IRQSTAT(port->id)) &
145 			__raw_readl(port->base + PINCTRL_IRQEN(port->id));
146 
147 	while (irq_stat != 0) {
148 		int irqoffset = fls(irq_stat) - 1;
149 		generic_handle_irq(gpio_irq_no_base + irqoffset);
150 		irq_stat &= ~(1 << irqoffset);
151 	}
152 }
153 
154 /*
155  * Set interrupt number "irq" in the GPIO as a wake-up source.
156  * While system is running, all registered GPIO interrupts need to have
157  * wake-up enabled. When system is suspended, only selected GPIO interrupts
158  * need to have wake-up enabled.
159  * @param  irq          interrupt source number
160  * @param  enable       enable as wake-up if equal to non-zero
161  * @return       This function returns 0 on success.
162  */
mxs_gpio_set_wake_irq(struct irq_data * d,unsigned int enable)163 static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable)
164 {
165 	u32 gpio = irq_to_gpio(d->irq);
166 	u32 gpio_idx = gpio & 0x1f;
167 	struct mxs_gpio_port *port = &mxs_gpio_ports[gpio / 32];
168 
169 	if (enable) {
170 		if (port->irq_high && (gpio_idx >= 16))
171 			enable_irq_wake(port->irq_high);
172 		else
173 			enable_irq_wake(port->irq);
174 	} else {
175 		if (port->irq_high && (gpio_idx >= 16))
176 			disable_irq_wake(port->irq_high);
177 		else
178 			disable_irq_wake(port->irq);
179 	}
180 
181 	return 0;
182 }
183 
184 static struct irq_chip gpio_irq_chip = {
185 	.name = "mxs gpio",
186 	.irq_ack = mxs_gpio_ack_irq,
187 	.irq_mask = mxs_gpio_mask_irq,
188 	.irq_unmask = mxs_gpio_unmask_irq,
189 	.irq_set_type = mxs_gpio_set_irq_type,
190 	.irq_set_wake = mxs_gpio_set_wake_irq,
191 };
192 
mxs_set_gpio_direction(struct gpio_chip * chip,unsigned offset,int dir)193 static void mxs_set_gpio_direction(struct gpio_chip *chip, unsigned offset,
194 				int dir)
195 {
196 	struct mxs_gpio_port *port =
197 		container_of(chip, struct mxs_gpio_port, chip);
198 	void __iomem *pin_addr = port->base + PINCTRL_DOE(port->id);
199 
200 	if (dir)
201 		__mxs_setl(1 << offset, pin_addr);
202 	else
203 		__mxs_clrl(1 << offset, pin_addr);
204 }
205 
mxs_gpio_get(struct gpio_chip * chip,unsigned offset)206 static int mxs_gpio_get(struct gpio_chip *chip, unsigned offset)
207 {
208 	struct mxs_gpio_port *port =
209 		container_of(chip, struct mxs_gpio_port, chip);
210 
211 	return (__raw_readl(port->base + PINCTRL_DIN(port->id)) >> offset) & 1;
212 }
213 
mxs_gpio_set(struct gpio_chip * chip,unsigned offset,int value)214 static void mxs_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
215 {
216 	struct mxs_gpio_port *port =
217 		container_of(chip, struct mxs_gpio_port, chip);
218 	void __iomem *pin_addr = port->base + PINCTRL_DOUT(port->id);
219 
220 	if (value)
221 		__mxs_setl(1 << offset, pin_addr);
222 	else
223 		__mxs_clrl(1 << offset, pin_addr);
224 }
225 
mxs_gpio_to_irq(struct gpio_chip * chip,unsigned offset)226 static int mxs_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
227 {
228 	struct mxs_gpio_port *port =
229 		container_of(chip, struct mxs_gpio_port, chip);
230 
231 	return port->virtual_irq_start + offset;
232 }
233 
mxs_gpio_direction_input(struct gpio_chip * chip,unsigned offset)234 static int mxs_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
235 {
236 	mxs_set_gpio_direction(chip, offset, 0);
237 	return 0;
238 }
239 
mxs_gpio_direction_output(struct gpio_chip * chip,unsigned offset,int value)240 static int mxs_gpio_direction_output(struct gpio_chip *chip,
241 				     unsigned offset, int value)
242 {
243 	mxs_gpio_set(chip, offset, value);
244 	mxs_set_gpio_direction(chip, offset, 1);
245 	return 0;
246 }
247 
mxs_gpio_init(struct mxs_gpio_port * port,int cnt)248 int __init mxs_gpio_init(struct mxs_gpio_port *port, int cnt)
249 {
250 	int i, j;
251 
252 	/* save for local usage */
253 	mxs_gpio_ports = port;
254 	gpio_table_size = cnt;
255 
256 	pr_info("MXS GPIO hardware\n");
257 
258 	for (i = 0; i < cnt; i++) {
259 		/* disable the interrupt and clear the status */
260 		__raw_writel(0, port[i].base + PINCTRL_PIN2IRQ(i));
261 		__raw_writel(0, port[i].base + PINCTRL_IRQEN(i));
262 
263 		/* clear address has to be used to clear IRQSTAT bits */
264 		__mxs_clrl(~0U, port[i].base + PINCTRL_IRQSTAT(i));
265 
266 		for (j = port[i].virtual_irq_start;
267 			j < port[i].virtual_irq_start + 32; j++) {
268 			irq_set_chip_and_handler(j, &gpio_irq_chip,
269 						 handle_level_irq);
270 			set_irq_flags(j, IRQF_VALID);
271 		}
272 
273 		/* setup one handler for each entry */
274 		irq_set_chained_handler(port[i].irq, mxs_gpio_irq_handler);
275 		irq_set_handler_data(port[i].irq, &port[i]);
276 
277 		/* register gpio chip */
278 		port[i].chip.direction_input = mxs_gpio_direction_input;
279 		port[i].chip.direction_output = mxs_gpio_direction_output;
280 		port[i].chip.get = mxs_gpio_get;
281 		port[i].chip.set = mxs_gpio_set;
282 		port[i].chip.to_irq = mxs_gpio_to_irq;
283 		port[i].chip.base = i * 32;
284 		port[i].chip.ngpio = 32;
285 
286 		/* its a serious configuration bug when it fails */
287 		BUG_ON(gpiochip_add(&port[i].chip) < 0);
288 	}
289 
290 	return 0;
291 }
292 
293 #define MX23_GPIO_BASE	MX23_IO_ADDRESS(MX23_PINCTRL_BASE_ADDR)
294 #define MX28_GPIO_BASE	MX28_IO_ADDRESS(MX28_PINCTRL_BASE_ADDR)
295 
296 #define DEFINE_MXS_GPIO_PORT(_base, _irq, _id)				\
297 	{								\
298 		.chip.label = "gpio-" #_id,				\
299 		.id = _id,						\
300 		.irq = _irq,						\
301 		.base = _base,						\
302 		.virtual_irq_start = MXS_GPIO_IRQ_START + (_id) * 32,	\
303 	}
304 
305 #ifdef CONFIG_SOC_IMX23
306 static struct mxs_gpio_port mx23_gpio_ports[] = {
307 	DEFINE_MXS_GPIO_PORT(MX23_GPIO_BASE, MX23_INT_GPIO0, 0),
308 	DEFINE_MXS_GPIO_PORT(MX23_GPIO_BASE, MX23_INT_GPIO1, 1),
309 	DEFINE_MXS_GPIO_PORT(MX23_GPIO_BASE, MX23_INT_GPIO2, 2),
310 };
311 
mx23_register_gpios(void)312 int __init mx23_register_gpios(void)
313 {
314 	return mxs_gpio_init(mx23_gpio_ports, ARRAY_SIZE(mx23_gpio_ports));
315 }
316 #endif
317 
318 #ifdef CONFIG_SOC_IMX28
319 static struct mxs_gpio_port mx28_gpio_ports[] = {
320 	DEFINE_MXS_GPIO_PORT(MX28_GPIO_BASE, MX28_INT_GPIO0, 0),
321 	DEFINE_MXS_GPIO_PORT(MX28_GPIO_BASE, MX28_INT_GPIO1, 1),
322 	DEFINE_MXS_GPIO_PORT(MX28_GPIO_BASE, MX28_INT_GPIO2, 2),
323 	DEFINE_MXS_GPIO_PORT(MX28_GPIO_BASE, MX28_INT_GPIO3, 3),
324 	DEFINE_MXS_GPIO_PORT(MX28_GPIO_BASE, MX28_INT_GPIO4, 4),
325 };
326 
mx28_register_gpios(void)327 int __init mx28_register_gpios(void)
328 {
329 	return mxs_gpio_init(mx28_gpio_ports, ARRAY_SIZE(mx28_gpio_ports));
330 }
331 #endif
332