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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 | // SPDX-License-Identifier: GPL-2.0-only /* * Altera University Program PS2 controller driver * * Copyright (C) 2008 Thomas Chou <thomas@wytron.com.tw> * * Based on sa1111ps2.c, which is: * Copyright (C) 2002 Russell King */ #include <linux/module.h> #include <linux/input.h> #include <linux/serio.h> #include <linux/interrupt.h> #include <linux/platform_device.h> #include <linux/io.h> #include <linux/slab.h> #include <linux/of.h> #define DRV_NAME "altera_ps2" struct ps2if { struct serio *io; void __iomem *base; }; /* * Read all bytes waiting in the PS2 port. There should be * at the most one, but we loop for safety. */ static irqreturn_t altera_ps2_rxint(int irq, void *dev_id) { struct ps2if *ps2if = dev_id; unsigned int status; irqreturn_t handled = IRQ_NONE; while ((status = readl(ps2if->base)) & 0xffff0000) { serio_interrupt(ps2if->io, status & 0xff, 0); handled = IRQ_HANDLED; } return handled; } /* * Write a byte to the PS2 port. */ static int altera_ps2_write(struct serio *io, unsigned char val) { struct ps2if *ps2if = io->port_data; writel(val, ps2if->base); return 0; } static int altera_ps2_open(struct serio *io) { struct ps2if *ps2if = io->port_data; /* clear fifo */ while (readl(ps2if->base) & 0xffff0000) /* empty */; writel(1, ps2if->base + 4); /* enable rx irq */ return 0; } static void altera_ps2_close(struct serio *io) { struct ps2if *ps2if = io->port_data; writel(0, ps2if->base + 4); /* disable rx irq */ } /* * Add one device to this driver. */ static int altera_ps2_probe(struct platform_device *pdev) { struct ps2if *ps2if; struct serio *serio; int error, irq; ps2if = devm_kzalloc(&pdev->dev, sizeof(struct ps2if), GFP_KERNEL); if (!ps2if) return -ENOMEM; ps2if->base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); if (IS_ERR(ps2if->base)) return PTR_ERR(ps2if->base); irq = platform_get_irq(pdev, 0); if (irq < 0) return -ENXIO; error = devm_request_irq(&pdev->dev, irq, altera_ps2_rxint, 0, pdev->name, ps2if); if (error) { dev_err(&pdev->dev, "could not request IRQ %d\n", irq); return error; } serio = kzalloc(sizeof(struct serio), GFP_KERNEL); if (!serio) return -ENOMEM; serio->id.type = SERIO_8042; serio->write = altera_ps2_write; serio->open = altera_ps2_open; serio->close = altera_ps2_close; strscpy(serio->name, dev_name(&pdev->dev), sizeof(serio->name)); strscpy(serio->phys, dev_name(&pdev->dev), sizeof(serio->phys)); serio->port_data = ps2if; serio->dev.parent = &pdev->dev; ps2if->io = serio; dev_info(&pdev->dev, "base %p, irq %d\n", ps2if->base, irq); serio_register_port(ps2if->io); platform_set_drvdata(pdev, ps2if); return 0; } /* * Remove one device from this driver. */ static void altera_ps2_remove(struct platform_device *pdev) { struct ps2if *ps2if = platform_get_drvdata(pdev); serio_unregister_port(ps2if->io); } #ifdef CONFIG_OF static const struct of_device_id altera_ps2_match[] = { { .compatible = "ALTR,ps2-1.0", }, { .compatible = "altr,ps2-1.0", }, {}, }; MODULE_DEVICE_TABLE(of, altera_ps2_match); #endif /* CONFIG_OF */ /* * Our device driver structure */ static struct platform_driver altera_ps2_driver = { .probe = altera_ps2_probe, .remove_new = altera_ps2_remove, .driver = { .name = DRV_NAME, .of_match_table = of_match_ptr(altera_ps2_match), }, }; module_platform_driver(altera_ps2_driver); MODULE_DESCRIPTION("Altera University Program PS2 controller driver"); MODULE_AUTHOR("Thomas Chou <thomas@wytron.com.tw>"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:" DRV_NAME); |