Linux 3.11-rc3
[cris-mirror.git] / drivers / gpio / gpio-ge.c
blob7b95a4a8318c2bd43b0926521a39a2860f8f30ee
1 /*
2 * Driver for GE FPGA based GPIO
4 * Author: Martyn Welch <martyn.welch@ge.com>
6 * 2008 (c) GE Intelligent Platforms Embedded Systems, Inc.
8 * This file is licensed under the terms of the GNU General Public License
9 * version 2. This program is licensed "as is" without any warranty of any
10 * kind, whether express or implied.
13 /* TODO
15 * Configuration of output modes (totem-pole/open-drain)
16 * Interrupt configuration - interrupts are always generated the FPGA relies on
17 * the I/O interrupt controllers mask to stop them propergating
20 #include <linux/kernel.h>
21 #include <linux/compiler.h>
22 #include <linux/init.h>
23 #include <linux/io.h>
24 #include <linux/of.h>
25 #include <linux/of_device.h>
26 #include <linux/of_platform.h>
27 #include <linux/of_gpio.h>
28 #include <linux/gpio.h>
29 #include <linux/slab.h>
30 #include <linux/module.h>
32 #define GEF_GPIO_DIRECT 0x00
33 #define GEF_GPIO_IN 0x04
34 #define GEF_GPIO_OUT 0x08
35 #define GEF_GPIO_TRIG 0x0C
36 #define GEF_GPIO_POLAR_A 0x10
37 #define GEF_GPIO_POLAR_B 0x14
38 #define GEF_GPIO_INT_STAT 0x18
39 #define GEF_GPIO_OVERRUN 0x1C
40 #define GEF_GPIO_MODE 0x20
42 static void _gef_gpio_set(void __iomem *reg, unsigned int offset, int value)
44 unsigned int data;
46 data = ioread32be(reg);
47 /* value: 0=low; 1=high */
48 if (value & 0x1)
49 data = data | (0x1 << offset);
50 else
51 data = data & ~(0x1 << offset);
53 iowrite32be(data, reg);
57 static int gef_gpio_dir_in(struct gpio_chip *chip, unsigned offset)
59 unsigned int data;
60 struct of_mm_gpio_chip *mmchip = to_of_mm_gpio_chip(chip);
62 data = ioread32be(mmchip->regs + GEF_GPIO_DIRECT);
63 data = data | (0x1 << offset);
64 iowrite32be(data, mmchip->regs + GEF_GPIO_DIRECT);
66 return 0;
69 static int gef_gpio_dir_out(struct gpio_chip *chip, unsigned offset, int value)
71 unsigned int data;
72 struct of_mm_gpio_chip *mmchip = to_of_mm_gpio_chip(chip);
74 /* Set direction before switching to input */
75 _gef_gpio_set(mmchip->regs + GEF_GPIO_OUT, offset, value);
77 data = ioread32be(mmchip->regs + GEF_GPIO_DIRECT);
78 data = data & ~(0x1 << offset);
79 iowrite32be(data, mmchip->regs + GEF_GPIO_DIRECT);
81 return 0;
84 static int gef_gpio_get(struct gpio_chip *chip, unsigned offset)
86 unsigned int data;
87 int state = 0;
88 struct of_mm_gpio_chip *mmchip = to_of_mm_gpio_chip(chip);
90 data = ioread32be(mmchip->regs + GEF_GPIO_IN);
91 state = (int)((data >> offset) & 0x1);
93 return state;
96 static void gef_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
98 struct of_mm_gpio_chip *mmchip = to_of_mm_gpio_chip(chip);
100 _gef_gpio_set(mmchip->regs + GEF_GPIO_OUT, offset, value);
103 static int __init gef_gpio_init(void)
105 struct device_node *np;
106 int retval;
107 struct of_mm_gpio_chip *gef_gpio_chip;
109 for_each_compatible_node(np, NULL, "gef,sbc610-gpio") {
111 pr_debug("%s: Initialising GEF GPIO\n", np->full_name);
113 /* Allocate chip structure */
114 gef_gpio_chip = kzalloc(sizeof(*gef_gpio_chip), GFP_KERNEL);
115 if (!gef_gpio_chip) {
116 pr_err("%s: Unable to allocate structure\n",
117 np->full_name);
118 continue;
121 /* Setup pointers to chip functions */
122 gef_gpio_chip->gc.of_gpio_n_cells = 2;
123 gef_gpio_chip->gc.ngpio = 19;
124 gef_gpio_chip->gc.direction_input = gef_gpio_dir_in;
125 gef_gpio_chip->gc.direction_output = gef_gpio_dir_out;
126 gef_gpio_chip->gc.get = gef_gpio_get;
127 gef_gpio_chip->gc.set = gef_gpio_set;
129 /* This function adds a memory mapped GPIO chip */
130 retval = of_mm_gpiochip_add(np, gef_gpio_chip);
131 if (retval) {
132 kfree(gef_gpio_chip);
133 pr_err("%s: Unable to add GPIO\n", np->full_name);
137 for_each_compatible_node(np, NULL, "gef,sbc310-gpio") {
139 pr_debug("%s: Initialising GEF GPIO\n", np->full_name);
141 /* Allocate chip structure */
142 gef_gpio_chip = kzalloc(sizeof(*gef_gpio_chip), GFP_KERNEL);
143 if (!gef_gpio_chip) {
144 pr_err("%s: Unable to allocate structure\n",
145 np->full_name);
146 continue;
149 /* Setup pointers to chip functions */
150 gef_gpio_chip->gc.of_gpio_n_cells = 2;
151 gef_gpio_chip->gc.ngpio = 6;
152 gef_gpio_chip->gc.direction_input = gef_gpio_dir_in;
153 gef_gpio_chip->gc.direction_output = gef_gpio_dir_out;
154 gef_gpio_chip->gc.get = gef_gpio_get;
155 gef_gpio_chip->gc.set = gef_gpio_set;
157 /* This function adds a memory mapped GPIO chip */
158 retval = of_mm_gpiochip_add(np, gef_gpio_chip);
159 if (retval) {
160 kfree(gef_gpio_chip);
161 pr_err("%s: Unable to add GPIO\n", np->full_name);
165 for_each_compatible_node(np, NULL, "ge,imp3a-gpio") {
167 pr_debug("%s: Initialising GE GPIO\n", np->full_name);
169 /* Allocate chip structure */
170 gef_gpio_chip = kzalloc(sizeof(*gef_gpio_chip), GFP_KERNEL);
171 if (!gef_gpio_chip) {
172 pr_err("%s: Unable to allocate structure\n",
173 np->full_name);
174 continue;
177 /* Setup pointers to chip functions */
178 gef_gpio_chip->gc.of_gpio_n_cells = 2;
179 gef_gpio_chip->gc.ngpio = 16;
180 gef_gpio_chip->gc.direction_input = gef_gpio_dir_in;
181 gef_gpio_chip->gc.direction_output = gef_gpio_dir_out;
182 gef_gpio_chip->gc.get = gef_gpio_get;
183 gef_gpio_chip->gc.set = gef_gpio_set;
185 /* This function adds a memory mapped GPIO chip */
186 retval = of_mm_gpiochip_add(np, gef_gpio_chip);
187 if (retval) {
188 kfree(gef_gpio_chip);
189 pr_err("%s: Unable to add GPIO\n", np->full_name);
193 return 0;
195 arch_initcall(gef_gpio_init);
197 MODULE_DESCRIPTION("GE I/O FPGA GPIO driver");
198 MODULE_AUTHOR("Martyn Welch <martyn.welch@ge.com");
199 MODULE_LICENSE("GPL");