2 * GPIO support for RDC SoC R3210/R8610
4 * Copyright (C) 2007, Florian Fainelli <florian@openwrt.org>
5 * Copyright (C) 2008, Volker Weiss <dev@tintuc.de>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (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.
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., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #include <linux/spinlock.h>
26 #include <linux/types.h>
27 #include <linux/module.h>
29 #include <asm/rdc321x_gpio.h>
30 #include <asm/rdc321x_defs.h>
33 /* spin lock to protect our private copy of GPIO data register plus
34 the access to PCI conf registers. */
35 static DEFINE_SPINLOCK(gpio_lock);
37 /* copy of GPIO data registers */
38 static u32 gpio_data_reg1;
39 static u32 gpio_data_reg2;
41 static u32 gpio_request_data[2];
44 static inline void rdc321x_conf_write(unsigned addr, u32 value)
46 outl((1 << 31) | (7 << 11) | addr, RDC3210_CFGREG_ADDR);
47 outl(value, RDC3210_CFGREG_DATA);
50 static inline void rdc321x_conf_or(unsigned addr, u32 value)
52 outl((1 << 31) | (7 << 11) | addr, RDC3210_CFGREG_ADDR);
53 value |= inl(RDC3210_CFGREG_DATA);
54 outl(value, RDC3210_CFGREG_DATA);
57 static inline u32 rdc321x_conf_read(unsigned addr)
59 outl((1 << 31) | (7 << 11) | addr, RDC3210_CFGREG_ADDR);
61 return inl(RDC3210_CFGREG_DATA);
64 /* configure pin as GPIO */
65 static void rdc321x_configure_gpio(unsigned gpio)
69 spin_lock_irqsave(&gpio_lock, flags);
70 rdc321x_conf_or(gpio < 32
71 ? RDC321X_GPIO_CTRL_REG1 : RDC321X_GPIO_CTRL_REG2,
73 spin_unlock_irqrestore(&gpio_lock, flags);
76 /* initially setup the 2 copies of the gpio data registers.
77 This function is called before the platform setup code. */
78 static int __init rdc321x_gpio_setup(void)
80 /* this might not be, what others (BIOS, bootloader, etc.)
81 wrote to these registers before, but it's a good guess. Still
82 better than just using 0xffffffff. */
84 gpio_data_reg1 = rdc321x_conf_read(RDC321X_GPIO_DATA_REG1);
85 gpio_data_reg2 = rdc321x_conf_read(RDC321X_GPIO_DATA_REG2);
90 /* determine, if gpio number is valid */
91 static inline int rdc321x_is_gpio(unsigned gpio)
93 return gpio <= RDC321X_MAX_GPIO;
97 int rdc_gpio_request(unsigned gpio, const char *label)
101 if (!rdc321x_is_gpio(gpio))
104 spin_lock_irqsave(&gpio_lock, flags);
105 if (gpio_request_data[(gpio & 0x20) ? 1 : 0] & (1 << (gpio & 0x1f)))
107 gpio_request_data[(gpio & 0x20) ? 1 : 0] |= (1 << (gpio & 0x1f));
108 spin_unlock_irqrestore(&gpio_lock, flags);
112 spin_unlock_irqrestore(&gpio_lock, flags);
115 EXPORT_SYMBOL(rdc_gpio_request);
117 /* release previously-claimed GPIO */
118 void rdc_gpio_free(unsigned gpio)
122 if (!rdc321x_is_gpio(gpio))
125 spin_lock_irqsave(&gpio_lock, flags);
126 gpio_request_data[(gpio & 0x20) ? 1 : 0] &= ~(1 << (gpio & 0x1f));
127 spin_unlock_irqrestore(&gpio_lock, flags);
129 EXPORT_SYMBOL(rdc_gpio_free);
132 int rdc_gpio_get_value(unsigned gpio)
137 spin_lock_irqsave(&gpio_lock, flags);
138 reg = rdc321x_conf_read(gpio < 32
139 ? RDC321X_GPIO_DATA_REG1 : RDC321X_GPIO_DATA_REG2);
140 spin_unlock_irqrestore(&gpio_lock, flags);
142 return (1 << (gpio & 0x1f)) & reg ? 1 : 0;
144 EXPORT_SYMBOL(rdc_gpio_get_value);
146 /* set GPIO pin to value */
147 void rdc_gpio_set_value(unsigned gpio, int value)
152 reg = 1 << (gpio & 0x1f);
154 spin_lock_irqsave(&gpio_lock, flags);
156 gpio_data_reg1 |= reg;
158 gpio_data_reg1 &= ~reg;
159 rdc321x_conf_write(RDC321X_GPIO_DATA_REG1, gpio_data_reg1);
160 spin_unlock_irqrestore(&gpio_lock, flags);
162 spin_lock_irqsave(&gpio_lock, flags);
164 gpio_data_reg2 |= reg;
166 gpio_data_reg2 &= ~reg;
167 rdc321x_conf_write(RDC321X_GPIO_DATA_REG2, gpio_data_reg2);
168 spin_unlock_irqrestore(&gpio_lock, flags);
171 EXPORT_SYMBOL(rdc_gpio_set_value);
173 /* configure GPIO pin as input */
174 int rdc_gpio_direction_input(unsigned gpio)
176 if (!rdc321x_is_gpio(gpio))
179 rdc321x_configure_gpio(gpio);
183 EXPORT_SYMBOL(rdc_gpio_direction_input);
185 /* configure GPIO pin as output and set value */
186 int rdc_gpio_direction_output(unsigned gpio, int value)
188 if (!rdc321x_is_gpio(gpio))
191 gpio_set_value(gpio, value);
192 rdc321x_configure_gpio(gpio);
196 EXPORT_SYMBOL(rdc_gpio_direction_output);
198 arch_initcall(rdc321x_gpio_setup);