2 * Miscellaneous functions for IDT EB434 board
4 * Copyright 2004 IDT Inc. (rischelp@idt.com)
5 * Copyright 2006 Phil Sutter <n0-1@freewrt.org>
6 * Copyright 2007 Florian Fainelli <florian@openwrt.org>
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
14 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
15 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
16 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
19 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
20 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 * You should have received a copy of the GNU General Public License along
25 * with this program; if not, write to the Free Software Foundation, Inc.,
26 * 675 Mass Ave, Cambridge, MA 02139, USA.
29 #include <linux/kernel.h>
30 #include <linux/init.h>
31 #include <linux/types.h>
32 #include <linux/export.h>
33 #include <linux/spinlock.h>
34 #include <linux/platform_device.h>
35 #include <linux/gpio/driver.h>
37 #include <asm/mach-rc32434/rb.h>
38 #include <asm/mach-rc32434/gpio.h>
40 struct rb532_gpio_chip
{
41 struct gpio_chip chip
;
42 void __iomem
*regbase
;
45 static struct resource rb532_gpio_reg0_res
[] = {
48 .start
= REGBASE
+ GPIOBASE
,
49 .end
= REGBASE
+ GPIOBASE
+ sizeof(struct rb532_gpio_reg
) - 1,
50 .flags
= IORESOURCE_MEM
,
54 /* rb532_set_bit - sanely set a bit
56 * bitval: new value for the bit
57 * offset: bit index in the 4 byte address range
58 * ioaddr: 4 byte aligned address being altered
60 static inline void rb532_set_bit(unsigned bitval
,
61 unsigned offset
, void __iomem
*ioaddr
)
66 local_irq_save(flags
);
69 val
&= ~(!bitval
<< offset
); /* unset bit if bitval == 0 */
70 val
|= (!!bitval
<< offset
); /* set bit if bitval == 1 */
73 local_irq_restore(flags
);
76 /* rb532_get_bit - read a bit
78 * returns the boolean state of the bit, which may be > 1
80 static inline int rb532_get_bit(unsigned offset
, void __iomem
*ioaddr
)
82 return readl(ioaddr
) & (1 << offset
);
86 * Return GPIO level */
87 static int rb532_gpio_get(struct gpio_chip
*chip
, unsigned offset
)
89 struct rb532_gpio_chip
*gpch
;
91 gpch
= gpiochip_get_data(chip
);
92 return !!rb532_get_bit(offset
, gpch
->regbase
+ GPIOD
);
96 * Set output GPIO level
98 static void rb532_gpio_set(struct gpio_chip
*chip
,
99 unsigned offset
, int value
)
101 struct rb532_gpio_chip
*gpch
;
103 gpch
= gpiochip_get_data(chip
);
104 rb532_set_bit(value
, offset
, gpch
->regbase
+ GPIOD
);
108 * Set GPIO direction to input
110 static int rb532_gpio_direction_input(struct gpio_chip
*chip
, unsigned offset
)
112 struct rb532_gpio_chip
*gpch
;
114 gpch
= gpiochip_get_data(chip
);
116 /* disable alternate function in case it's set */
117 rb532_set_bit(0, offset
, gpch
->regbase
+ GPIOFUNC
);
119 rb532_set_bit(0, offset
, gpch
->regbase
+ GPIOCFG
);
124 * Set GPIO direction to output
126 static int rb532_gpio_direction_output(struct gpio_chip
*chip
,
127 unsigned offset
, int value
)
129 struct rb532_gpio_chip
*gpch
;
131 gpch
= gpiochip_get_data(chip
);
133 /* disable alternate function in case it's set */
134 rb532_set_bit(0, offset
, gpch
->regbase
+ GPIOFUNC
);
136 /* set the initial output value */
137 rb532_set_bit(value
, offset
, gpch
->regbase
+ GPIOD
);
139 rb532_set_bit(1, offset
, gpch
->regbase
+ GPIOCFG
);
143 static int rb532_gpio_to_irq(struct gpio_chip
*chip
, unsigned gpio
)
145 return 8 + 4 * 32 + gpio
;
148 static struct rb532_gpio_chip rb532_gpio_chip
[] = {
152 .direction_input
= rb532_gpio_direction_input
,
153 .direction_output
= rb532_gpio_direction_output
,
154 .get
= rb532_gpio_get
,
155 .set
= rb532_gpio_set
,
156 .to_irq
= rb532_gpio_to_irq
,
164 * Set GPIO interrupt level
166 void rb532_gpio_set_ilevel(int bit
, unsigned gpio
)
168 rb532_set_bit(bit
, gpio
, rb532_gpio_chip
->regbase
+ GPIOILEVEL
);
170 EXPORT_SYMBOL(rb532_gpio_set_ilevel
);
173 * Set GPIO interrupt status
175 void rb532_gpio_set_istat(int bit
, unsigned gpio
)
177 rb532_set_bit(bit
, gpio
, rb532_gpio_chip
->regbase
+ GPIOISTAT
);
179 EXPORT_SYMBOL(rb532_gpio_set_istat
);
182 * Configure GPIO alternate function
184 void rb532_gpio_set_func(unsigned gpio
)
186 rb532_set_bit(1, gpio
, rb532_gpio_chip
->regbase
+ GPIOFUNC
);
188 EXPORT_SYMBOL(rb532_gpio_set_func
);
190 int __init
rb532_gpio_init(void)
194 r
= rb532_gpio_reg0_res
;
195 rb532_gpio_chip
->regbase
= ioremap(r
->start
, resource_size(r
));
197 if (!rb532_gpio_chip
->regbase
) {
198 printk(KERN_ERR
"rb532: cannot remap GPIO register 0\n");
202 /* Register our GPIO chip */
203 gpiochip_add_data(&rb532_gpio_chip
->chip
, rb532_gpio_chip
);
207 arch_initcall(rb532_gpio_init
);