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, sizeof(*gc), GFP_KERNEL); 60 if (!gc) 61 return -ENOMEM; 62 63 regs = devm_platform_ioremap_resource(pdev, 0); 64 if (IS_ERR(regs)) 65 return PTR_ERR(regs); 66 67 ret = bgpio_init(gc, dev, 4, regs + GEF_GPIO_IN, regs + GEF_GPIO_OUT, 68 NULL, NULL, regs + GEF_GPIO_DIRECT, 69 BGPIOF_BIG_ENDIAN_BYTE_ORDER); 70 if (ret) 71 return dev_err_probe(dev, ret, "bgpio_init failed\n"); 72 73 /* Setup pointers to chip functions */ 74 gc->label = devm_kasprintf(dev, GFP_KERNEL, "%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, ret, "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