2 * arch/arm/plat-orion/gpio.c
4 * Marvell Orion SoC GPIO handling.
6 * This file is licensed under the terms of the GNU General Public
7 * License version 2. This program is licensed "as is" without any
8 * warranty of any kind, whether express or implied.
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/spinlock.h>
15 #include <linux/bitops.h>
19 static DEFINE_SPINLOCK(gpio_lock);
20 static const char *gpio_label[GPIO_MAX]; /* non null for allocated GPIOs */
21 static unsigned long gpio_valid[BITS_TO_LONGS(GPIO_MAX)];
23 static inline void __set_direction(unsigned pin, int input)
27 u = readl(GPIO_IO_CONF(pin));
31 u &= ~(1 << (pin & 31));
32 writel(u, GPIO_IO_CONF(pin));
35 static void __set_level(unsigned pin, int high)
39 u = readl(GPIO_OUT(pin));
43 u &= ~(1 << (pin & 31));
44 writel(u, GPIO_OUT(pin));
49 * GENERIC_GPIO primitives.
51 int gpio_direction_input(unsigned pin)
55 if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
56 pr_debug("%s: invalid GPIO %d\n", __func__, pin);
60 spin_lock_irqsave(&gpio_lock, flags);
63 * Some callers might not have used gpio_request(),
64 * so flag this pin as requested now.
66 if (gpio_label[pin] == NULL)
67 gpio_label[pin] = "?";
70 * Configure GPIO direction.
72 __set_direction(pin, 1);
74 spin_unlock_irqrestore(&gpio_lock, flags);
78 EXPORT_SYMBOL(gpio_direction_input);
80 int gpio_direction_output(unsigned pin, int value)
85 if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
86 pr_debug("%s: invalid GPIO %d\n", __func__, pin);
90 spin_lock_irqsave(&gpio_lock, flags);
93 * Some callers might not have used gpio_request(),
94 * so flag this pin as requested now.
96 if (gpio_label[pin] == NULL)
97 gpio_label[pin] = "?";
102 u = readl(GPIO_BLINK_EN(pin));
103 u &= ~(1 << (pin & 31));
104 writel(u, GPIO_BLINK_EN(pin));
107 * Configure GPIO output value.
109 __set_level(pin, value);
112 * Configure GPIO direction.
114 __set_direction(pin, 0);
116 spin_unlock_irqrestore(&gpio_lock, flags);
120 EXPORT_SYMBOL(gpio_direction_output);
122 int gpio_get_value(unsigned pin)
126 if (readl(GPIO_IO_CONF(pin)) & (1 << (pin & 31)))
127 val = readl(GPIO_DATA_IN(pin)) ^ readl(GPIO_IN_POL(pin));
129 val = readl(GPIO_OUT(pin));
131 return (val >> (pin & 31)) & 1;
133 EXPORT_SYMBOL(gpio_get_value);
135 void gpio_set_value(unsigned pin, int value)
140 spin_lock_irqsave(&gpio_lock, flags);
145 u = readl(GPIO_BLINK_EN(pin));
146 u &= ~(1 << (pin & 31));
147 writel(u, GPIO_BLINK_EN(pin));
150 * Configure GPIO output value.
152 __set_level(pin, value);
154 spin_unlock_irqrestore(&gpio_lock, flags);
156 EXPORT_SYMBOL(gpio_set_value);
158 int gpio_request(unsigned pin, const char *label)
163 if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
164 pr_debug("%s: invalid GPIO %d\n", __func__, pin);
168 spin_lock_irqsave(&gpio_lock, flags);
169 if (gpio_label[pin] == NULL) {
170 gpio_label[pin] = label ? label : "?";
173 pr_debug("%s: GPIO %d already used as %s\n",
174 __func__, pin, gpio_label[pin]);
177 spin_unlock_irqrestore(&gpio_lock, flags);
181 EXPORT_SYMBOL(gpio_request);
183 void gpio_free(unsigned pin)
185 if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
186 pr_debug("%s: invalid GPIO %d\n", __func__, pin);
190 if (gpio_label[pin] == NULL)
191 pr_warning("%s: GPIO %d already freed\n", __func__, pin);
193 gpio_label[pin] = NULL;
195 EXPORT_SYMBOL(gpio_free);
199 * Orion-specific GPIO API extensions.
201 void __init orion_gpio_set_unused(unsigned pin)
204 * Configure as output, drive low.
207 __set_direction(pin, 0);
210 void __init orion_gpio_set_valid(unsigned pin, int valid)
213 __set_bit(pin, gpio_valid);
215 __clear_bit(pin, gpio_valid);
218 void orion_gpio_set_blink(unsigned pin, int blink)
223 spin_lock_irqsave(&gpio_lock, flags);
226 * Set output value to zero.
230 u = readl(GPIO_BLINK_EN(pin));
232 u |= 1 << (pin & 31);
234 u &= ~(1 << (pin & 31));
235 writel(u, GPIO_BLINK_EN(pin));
237 spin_unlock_irqrestore(&gpio_lock, flags);
239 EXPORT_SYMBOL(orion_gpio_set_blink);