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1/*
2 * Driver for GE FPGA based GPIO
3 *
4 * Author: Martyn Welch <martyn.welch@ge.com>
5 *
6 * 2008 (c) GE Intelligent Platforms Embedded Systems, Inc.
7 *
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.
11 */
12
13/* TODO
14 *
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
18 */
19
20#include <linux/kernel.h>
21#include <linux/io.h>
22#include <linux/slab.h>
23#include <linux/of_device.h>
24#include <linux/of_gpio.h>
25#include <linux/of_address.h>
26#include <linux/module.h>
27#include <linux/gpio/driver.h>
28
29#define GEF_GPIO_DIRECT 0x00
30#define GEF_GPIO_IN 0x04
31#define GEF_GPIO_OUT 0x08
32#define GEF_GPIO_TRIG 0x0C
33#define GEF_GPIO_POLAR_A 0x10
34#define GEF_GPIO_POLAR_B 0x14
35#define GEF_GPIO_INT_STAT 0x18
36#define GEF_GPIO_OVERRUN 0x1C
37#define GEF_GPIO_MODE 0x20
38
39static const struct of_device_id gef_gpio_ids[] = {
40 {
41 .compatible = "gef,sbc610-gpio",
42 .data = (void *)19,
43 }, {
44 .compatible = "gef,sbc310-gpio",
45 .data = (void *)6,
46 }, {
47 .compatible = "ge,imp3a-gpio",
48 .data = (void *)16,
49 },
50 { }
51};
52MODULE_DEVICE_TABLE(of, gef_gpio_ids);
53
54static int __init gef_gpio_probe(struct platform_device *pdev)
55{
56 const struct of_device_id *of_id =
57 of_match_device(gef_gpio_ids, &pdev->dev);
58 struct gpio_chip *gc;
59 void __iomem *regs;
60 int ret;
61
62 gc = devm_kzalloc(&pdev->dev, sizeof(*gc), GFP_KERNEL);
63 if (!gc)
64 return -ENOMEM;
65
66 regs = of_iomap(pdev->dev.of_node, 0);
67 if (!regs)
68 return -ENOMEM;
69
70 ret = bgpio_init(gc, &pdev->dev, 4, regs + GEF_GPIO_IN,
71 regs + GEF_GPIO_OUT, NULL, NULL,
72 regs + GEF_GPIO_DIRECT, BGPIOF_BIG_ENDIAN_BYTE_ORDER);
73 if (ret) {
74 dev_err(&pdev->dev, "bgpio_init failed\n");
75 goto err0;
76 }
77
78 /* Setup pointers to chip functions */
79 gc->label = devm_kstrdup(&pdev->dev, pdev->dev.of_node->full_name,
80 GFP_KERNEL);
81 if (!gc->label) {
82 ret = -ENOMEM;
83 goto err0;
84 }
85
86 gc->base = -1;
87 gc->ngpio = (u16)(uintptr_t)of_id->data;
88 gc->of_gpio_n_cells = 2;
89 gc->of_node = pdev->dev.of_node;
90
91 /* This function adds a memory mapped GPIO chip */
92 ret = devm_gpiochip_add_data(&pdev->dev, gc, NULL);
93 if (ret)
94 goto err0;
95
96 return 0;
97err0:
98 iounmap(regs);
99 pr_err("%s: GPIO chip registration failed\n",
100 pdev->dev.of_node->full_name);
101 return ret;
102};
103
104static struct platform_driver gef_gpio_driver = {
105 .driver = {
106 .name = "gef-gpio",
107 .of_match_table = gef_gpio_ids,
108 },
109};
110module_platform_driver_probe(gef_gpio_driver, gef_gpio_probe);
111
112MODULE_DESCRIPTION("GE I/O FPGA GPIO driver");
113MODULE_AUTHOR("Martyn Welch <martyn.welch@ge.com");
114MODULE_LICENSE("GPL");
1/*
2 * Driver for GE FPGA based GPIO
3 *
4 * Author: Martyn Welch <martyn.welch@ge.com>
5 *
6 * 2008 (c) GE Intelligent Platforms Embedded Systems, Inc.
7 *
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.
11 */
12
13/* TODO
14 *
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
18 */
19
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>
31
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
41
42static void _gef_gpio_set(void __iomem *reg, unsigned int offset, int value)
43{
44 unsigned int data;
45
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);
52
53 iowrite32be(data, reg);
54}
55
56
57static int gef_gpio_dir_in(struct gpio_chip *chip, unsigned offset)
58{
59 unsigned int data;
60 struct of_mm_gpio_chip *mmchip = to_of_mm_gpio_chip(chip);
61
62 data = ioread32be(mmchip->regs + GEF_GPIO_DIRECT);
63 data = data | (0x1 << offset);
64 iowrite32be(data, mmchip->regs + GEF_GPIO_DIRECT);
65
66 return 0;
67}
68
69static int gef_gpio_dir_out(struct gpio_chip *chip, unsigned offset, int value)
70{
71 unsigned int data;
72 struct of_mm_gpio_chip *mmchip = to_of_mm_gpio_chip(chip);
73
74 /* Set direction before switching to input */
75 _gef_gpio_set(mmchip->regs + GEF_GPIO_OUT, offset, value);
76
77 data = ioread32be(mmchip->regs + GEF_GPIO_DIRECT);
78 data = data & ~(0x1 << offset);
79 iowrite32be(data, mmchip->regs + GEF_GPIO_DIRECT);
80
81 return 0;
82}
83
84static int gef_gpio_get(struct gpio_chip *chip, unsigned offset)
85{
86 unsigned int data;
87 int state = 0;
88 struct of_mm_gpio_chip *mmchip = to_of_mm_gpio_chip(chip);
89
90 data = ioread32be(mmchip->regs + GEF_GPIO_IN);
91 state = (int)((data >> offset) & 0x1);
92
93 return state;
94}
95
96static void gef_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
97{
98 struct of_mm_gpio_chip *mmchip = to_of_mm_gpio_chip(chip);
99
100 _gef_gpio_set(mmchip->regs + GEF_GPIO_OUT, offset, value);
101}
102
103static int __init gef_gpio_init(void)
104{
105 struct device_node *np;
106 int retval;
107 struct of_mm_gpio_chip *gef_gpio_chip;
108
109 for_each_compatible_node(np, NULL, "gef,sbc610-gpio") {
110
111 pr_debug("%s: Initialising GEF GPIO\n", np->full_name);
112
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;
119 }
120
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;
128
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);
134 }
135 }
136
137 for_each_compatible_node(np, NULL, "gef,sbc310-gpio") {
138
139 pr_debug("%s: Initialising GEF GPIO\n", np->full_name);
140
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;
147 }
148
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;
156
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);
162 }
163 }
164
165 for_each_compatible_node(np, NULL, "ge,imp3a-gpio") {
166
167 pr_debug("%s: Initialising GE GPIO\n", np->full_name);
168
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;
175 }
176
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;
184
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);
190 }
191 }
192
193 return 0;
194};
195arch_initcall(gef_gpio_init);
196
197MODULE_DESCRIPTION("GE I/O FPGA GPIO driver");
198MODULE_AUTHOR("Martyn Welch <martyn.welch@ge.com");
199MODULE_LICENSE("GPL");