| Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame] | 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/basic_mmio_gpio.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 | |
| 39 | static 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 | }; |
| 52 | MODULE_DEVICE_TABLE(of, gef_gpio_ids); |
| 53 | |
| 54 | static 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 bgpio_chip *bgc; |
| 59 | void __iomem *regs; |
| 60 | int ret; |
| 61 | |
| 62 | bgc = devm_kzalloc(&pdev->dev, sizeof(*bgc), GFP_KERNEL); |
| 63 | if (!bgc) |
| 64 | return -ENOMEM; |
| 65 | |
| 66 | regs = of_iomap(pdev->dev.of_node, 0); |
| 67 | if (!regs) |
| 68 | return -ENOMEM; |
| 69 | |
| 70 | ret = bgpio_init(bgc, &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 | bgc->gc.label = devm_kstrdup(&pdev->dev, pdev->dev.of_node->full_name, |
| 80 | GFP_KERNEL); |
| 81 | if (!bgc->gc.label) { |
| 82 | ret = -ENOMEM; |
| 83 | goto err0; |
| 84 | } |
| 85 | |
| 86 | bgc->gc.base = -1; |
| 87 | bgc->gc.ngpio = (u16)(uintptr_t)of_id->data; |
| 88 | bgc->gc.of_gpio_n_cells = 2; |
| 89 | bgc->gc.of_node = pdev->dev.of_node; |
| 90 | |
| 91 | /* This function adds a memory mapped GPIO chip */ |
| 92 | ret = gpiochip_add(&bgc->gc); |
| 93 | if (ret) |
| 94 | goto err0; |
| 95 | |
| 96 | return 0; |
| 97 | err0: |
| 98 | iounmap(regs); |
| 99 | pr_err("%s: GPIO chip registration failed\n", |
| 100 | pdev->dev.of_node->full_name); |
| 101 | return ret; |
| 102 | }; |
| 103 | |
| 104 | static struct platform_driver gef_gpio_driver = { |
| 105 | .driver = { |
| 106 | .name = "gef-gpio", |
| 107 | .of_match_table = gef_gpio_ids, |
| 108 | }, |
| 109 | }; |
| 110 | module_platform_driver_probe(gef_gpio_driver, gef_gpio_probe); |
| 111 | |
| 112 | MODULE_DESCRIPTION("GE I/O FPGA GPIO driver"); |
| 113 | MODULE_AUTHOR("Martyn Welch <martyn.welch@ge.com"); |
| 114 | MODULE_LICENSE("GPL"); |