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authorRussell King <rmk@dyn-67.arm.linux.org.uk>2008-07-10 11:41:50 -0400
committerRussell King <rmk+kernel@arm.linux.org.uk>2008-07-10 11:41:50 -0400
commitf0006314d37639714da9658cf4ff3f1f9f420764 (patch)
treeb8a18e014a40f2f8fd5148aab09c869dfaabd7a9 /arch/arm/plat-mxc/gpio.c
parenta177ba3b7a08beef3f0fe74efa0f90701891945a (diff)
parent1bd55a436f1f90de0e7f476e514e01bd67497b88 (diff)
Merge branch 'imx' into devel
Conflicts: arch/arm/mm/Kconfig
Diffstat (limited to 'arch/arm/plat-mxc/gpio.c')
-rw-r--r--arch/arm/plat-mxc/gpio.c253
1 files changed, 253 insertions, 0 deletions
diff --git a/arch/arm/plat-mxc/gpio.c b/arch/arm/plat-mxc/gpio.c
new file mode 100644
index 000000000000..4a7736717d86
--- /dev/null
+++ b/arch/arm/plat-mxc/gpio.c
@@ -0,0 +1,253 @@
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 2004-2006 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, MA 02110-1301, USA.
20 */
21
22#include <linux/init.h>
23#include <linux/io.h>
24#include <linux/irq.h>
25#include <linux/gpio.h>
26#include <asm/hardware.h>
27#include <asm-generic/bug.h>
28
29static struct mxc_gpio_port *mxc_gpio_ports;
30static int gpio_table_size;
31
32/* Note: This driver assumes 32 GPIOs are handled in one register */
33
34static void _clear_gpio_irqstatus(struct mxc_gpio_port *port, u32 index)
35{
36 __raw_writel(1 << index, port->base + GPIO_ISR);
37}
38
39static void _set_gpio_irqenable(struct mxc_gpio_port *port, u32 index,
40 int enable)
41{
42 u32 l;
43
44 l = __raw_readl(port->base + GPIO_IMR);
45 l = (l & (~(1 << index))) | (!!enable << index);
46 __raw_writel(l, port->base + GPIO_IMR);
47}
48
49static void gpio_ack_irq(u32 irq)
50{
51 u32 gpio = irq_to_gpio(irq);
52 _clear_gpio_irqstatus(&mxc_gpio_ports[gpio / 32], gpio & 0x1f);
53}
54
55static void gpio_mask_irq(u32 irq)
56{
57 u32 gpio = irq_to_gpio(irq);
58 _set_gpio_irqenable(&mxc_gpio_ports[gpio / 32], gpio & 0x1f, 0);
59}
60
61static void gpio_unmask_irq(u32 irq)
62{
63 u32 gpio = irq_to_gpio(irq);
64 _set_gpio_irqenable(&mxc_gpio_ports[gpio / 32], gpio & 0x1f, 1);
65}
66
67static int gpio_set_irq_type(u32 irq, u32 type)
68{
69 u32 gpio = irq_to_gpio(irq);
70 struct mxc_gpio_port *port = &mxc_gpio_ports[gpio / 32];
71 u32 bit, val;
72 int edge;
73 void __iomem *reg = port->base;
74
75 switch (type) {
76 case IRQT_RISING:
77 edge = GPIO_INT_RISE_EDGE;
78 break;
79 case IRQT_FALLING:
80 edge = GPIO_INT_FALL_EDGE;
81 break;
82 case IRQT_LOW:
83 edge = GPIO_INT_LOW_LEV;
84 break;
85 case IRQT_HIGH:
86 edge = GPIO_INT_HIGH_LEV;
87 break;
88 default: /* this includes IRQT_BOTHEDGE */
89 return -EINVAL;
90 }
91
92 reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */
93 bit = gpio & 0xf;
94 val = __raw_readl(reg) & ~(0x3 << (bit << 1));
95 __raw_writel(val | (edge << (bit << 1)), reg);
96 _clear_gpio_irqstatus(port, gpio & 0x1f);
97
98 return 0;
99}
100
101/* handle n interrupts in one status register */
102static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat)
103{
104 u32 gpio_irq_no;
105
106 gpio_irq_no = port->virtual_irq_start;
107 for (; irq_stat != 0; irq_stat >>= 1, gpio_irq_no++) {
108
109 if ((irq_stat & 1) == 0)
110 continue;
111
112 BUG_ON(!(irq_desc[gpio_irq_no].handle_irq));
113 irq_desc[gpio_irq_no].handle_irq(gpio_irq_no,
114 &irq_desc[gpio_irq_no]);
115 }
116}
117
118#ifdef CONFIG_ARCH_MX3
119/* MX3 has one interrupt *per* gpio port */
120static void mx3_gpio_irq_handler(u32 irq, struct irq_desc *desc)
121{
122 u32 irq_stat;
123 struct mxc_gpio_port *port = (struct mxc_gpio_port *)get_irq_data(irq);
124
125 irq_stat = __raw_readl(port->base + GPIO_ISR) &
126 __raw_readl(port->base + GPIO_IMR);
127 BUG_ON(!irq_stat);
128 mxc_gpio_irq_handler(port, irq_stat);
129}
130#endif
131
132#ifdef CONFIG_ARCH_MX2
133/* MX2 has one interrupt *for all* gpio ports */
134static void mx2_gpio_irq_handler(u32 irq, struct irq_desc *desc)
135{
136 int i;
137 u32 irq_msk, irq_stat;
138 struct mxc_gpio_port *port = (struct mxc_gpio_port *)get_irq_data(irq);
139
140 /* walk through all interrupt status registers */
141 for (i = 0; i < gpio_table_size; i++) {
142 irq_msk = __raw_readl(port[i].base + GPIO_IMR);
143 if (!irq_msk)
144 continue;
145
146 irq_stat = __raw_readl(port[i].base + GPIO_ISR) & irq_msk;
147 if (irq_stat)
148 mxc_gpio_irq_handler(&port[i], irq_stat);
149 }
150}
151#endif
152
153static struct irq_chip gpio_irq_chip = {
154 .ack = gpio_ack_irq,
155 .mask = gpio_mask_irq,
156 .unmask = gpio_unmask_irq,
157 .set_type = gpio_set_irq_type,
158};
159
160static void _set_gpio_direction(struct gpio_chip *chip, unsigned offset,
161 int dir)
162{
163 struct mxc_gpio_port *port =
164 container_of(chip, struct mxc_gpio_port, chip);
165 u32 l;
166
167 l = __raw_readl(port->base + GPIO_GDIR);
168 if (dir)
169 l |= 1 << offset;
170 else
171 l &= ~(1 << offset);
172 __raw_writel(l, port->base + GPIO_GDIR);
173}
174
175static void mxc_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
176{
177 struct mxc_gpio_port *port =
178 container_of(chip, struct mxc_gpio_port, chip);
179 void __iomem *reg = port->base + GPIO_DR;
180 u32 l;
181
182 l = (__raw_readl(reg) & (~(1 << offset))) | (value << offset);
183 __raw_writel(l, reg);
184}
185
186static int mxc_gpio_get(struct gpio_chip *chip, unsigned offset)
187{
188 struct mxc_gpio_port *port =
189 container_of(chip, struct mxc_gpio_port, chip);
190
191 return (__raw_readl(port->base + GPIO_DR) >> offset) & 1;
192}
193
194static int mxc_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
195{
196 _set_gpio_direction(chip, offset, 0);
197 return 0;
198}
199
200static int mxc_gpio_direction_output(struct gpio_chip *chip,
201 unsigned offset, int value)
202{
203 _set_gpio_direction(chip, offset, 1);
204 mxc_gpio_set(chip, offset, value);
205 return 0;
206}
207
208int __init mxc_gpio_init(struct mxc_gpio_port *port, int cnt)
209{
210 int i, j;
211
212 /* save for local usage */
213 mxc_gpio_ports = port;
214 gpio_table_size = cnt;
215
216 printk(KERN_INFO "MXC GPIO hardware\n");
217
218 for (i = 0; i < cnt; i++) {
219 /* disable the interrupt and clear the status */
220 __raw_writel(0, port[i].base + GPIO_IMR);
221 __raw_writel(~0, port[i].base + GPIO_ISR);
222 for (j = port[i].virtual_irq_start;
223 j < port[i].virtual_irq_start + 32; j++) {
224 set_irq_chip(j, &gpio_irq_chip);
225 set_irq_handler(j, handle_edge_irq);
226 set_irq_flags(j, IRQF_VALID);
227 }
228
229 /* register gpio chip */
230 port[i].chip.direction_input = mxc_gpio_direction_input;
231 port[i].chip.direction_output = mxc_gpio_direction_output;
232 port[i].chip.get = mxc_gpio_get;
233 port[i].chip.set = mxc_gpio_set;
234 port[i].chip.base = i * 32;
235 port[i].chip.ngpio = 32;
236
237 /* its a serious configuration bug when it fails */
238 BUG_ON( gpiochip_add(&port[i].chip) < 0 );
239
240#ifdef CONFIG_ARCH_MX3
241 /* setup one handler for each entry */
242 set_irq_chained_handler(port[i].irq, mx3_gpio_irq_handler);
243 set_irq_data(port[i].irq, &port[i]);
244#endif
245 }
246
247#ifdef CONFIG_ARCH_MX2
248 /* setup one handler for all GPIO interrupts */
249 set_irq_chained_handler(port[0].irq, mx2_gpio_irq_handler);
250 set_irq_data(port[0].irq, port);
251#endif
252 return 0;
253}