1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Driver for GE FPGA based GPIO |
4 | * |
5 | * Author: Martyn Welch <martyn.welch@ge.com> |
6 | * |
7 | * 2008 (c) GE Intelligent Platforms Embedded Systems, Inc. |
8 | */ |
9 | |
10 | /* |
11 | * TODO: |
12 | * |
13 | * Configuration of output modes (totem-pole/open-drain). |
14 | * Interrupt configuration - interrupts are always generated, the FPGA relies |
15 | * on the I/O interrupt controllers mask to stop them from being propagated. |
16 | */ |
17 | |
18 | #include <linux/gpio/driver.h> |
19 | #include <linux/io.h> |
20 | #include <linux/kernel.h> |
21 | #include <linux/mod_devicetable.h> |
22 | #include <linux/module.h> |
23 | #include <linux/platform_device.h> |
24 | #include <linux/property.h> |
25 | #include <linux/slab.h> |
26 | |
27 | #define GEF_GPIO_DIRECT 0x00 |
28 | #define GEF_GPIO_IN 0x04 |
29 | #define GEF_GPIO_OUT 0x08 |
30 | #define GEF_GPIO_TRIG 0x0C |
31 | #define GEF_GPIO_POLAR_A 0x10 |
32 | #define GEF_GPIO_POLAR_B 0x14 |
33 | #define GEF_GPIO_INT_STAT 0x18 |
34 | #define GEF_GPIO_OVERRUN 0x1C |
35 | #define GEF_GPIO_MODE 0x20 |
36 | |
37 | static const struct of_device_id gef_gpio_ids[] = { |
38 | { |
39 | .compatible = "gef,sbc610-gpio" , |
40 | .data = (void *)19, |
41 | }, { |
42 | .compatible = "gef,sbc310-gpio" , |
43 | .data = (void *)6, |
44 | }, { |
45 | .compatible = "ge,imp3a-gpio" , |
46 | .data = (void *)16, |
47 | }, |
48 | { } |
49 | }; |
50 | MODULE_DEVICE_TABLE(of, gef_gpio_ids); |
51 | |
52 | static int __init gef_gpio_probe(struct platform_device *pdev) |
53 | { |
54 | struct device *dev = &pdev->dev; |
55 | struct gpio_chip *gc; |
56 | void __iomem *regs; |
57 | int ret; |
58 | |
59 | gc = devm_kzalloc(dev, size: sizeof(*gc), GFP_KERNEL); |
60 | if (!gc) |
61 | return -ENOMEM; |
62 | |
63 | regs = devm_platform_ioremap_resource(pdev, index: 0); |
64 | if (IS_ERR(ptr: regs)) |
65 | return PTR_ERR(ptr: regs); |
66 | |
67 | ret = bgpio_init(gc, dev, sz: 4, dat: regs + GEF_GPIO_IN, set: regs + GEF_GPIO_OUT, |
68 | NULL, NULL, dirin: regs + GEF_GPIO_DIRECT, |
69 | BGPIOF_BIG_ENDIAN_BYTE_ORDER); |
70 | if (ret) |
71 | return dev_err_probe(dev, err: ret, fmt: "bgpio_init failed\n" ); |
72 | |
73 | /* Setup pointers to chip functions */ |
74 | gc->label = devm_kasprintf(dev, GFP_KERNEL, fmt: "%pfw" , dev_fwnode(dev)); |
75 | if (!gc->label) |
76 | return -ENOMEM; |
77 | |
78 | gc->base = -1; |
79 | gc->ngpio = (uintptr_t)device_get_match_data(dev); |
80 | |
81 | /* This function adds a memory mapped GPIO chip */ |
82 | ret = devm_gpiochip_add_data(dev, gc, NULL); |
83 | if (ret) |
84 | return dev_err_probe(dev, err: ret, fmt: "GPIO chip registration failed\n" ); |
85 | |
86 | return 0; |
87 | }; |
88 | |
89 | static struct platform_driver gef_gpio_driver = { |
90 | .driver = { |
91 | .name = "gef-gpio" , |
92 | .of_match_table = gef_gpio_ids, |
93 | }, |
94 | }; |
95 | module_platform_driver_probe(gef_gpio_driver, gef_gpio_probe); |
96 | |
97 | MODULE_DESCRIPTION("GE I/O FPGA GPIO driver" ); |
98 | MODULE_AUTHOR("Martyn Welch <martyn.welch@ge.com>" ); |
99 | MODULE_LICENSE("GPL" ); |
100 | |