drivers/input/serio/rpckbd.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Copyright (c) 2000-2001 Vojtech Pavlik
   4  *  Copyright (c) 2002 Russell King
   5  */
   6
   7 /*
   8  * Acorn RiscPC PS/2 keyboard controller driver for Linux/ARM
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/serio.h>
  14 #include <linux/err.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/io.h>
  17 #include <linux/slab.h>
  18
  19 #include <mach/hardware.h>
  20 #include <asm/hardware/iomd.h>
  21
  22 MODULE_AUTHOR("Vojtech Pavlik, Russell King");
  23 MODULE_DESCRIPTION("Acorn RiscPC PS/2 keyboard controller driver");
  24 MODULE_LICENSE("GPL");
  25 MODULE_ALIAS("platform:kart");
  26
  27 struct rpckbd_data {
  28         int tx_irq;
  29         int rx_irq;
  30 };
  31
  32 static int rpckbd_write(struct serio *port, unsigned char val)
  33 {
  34         while (!(iomd_readb(IOMD_KCTRL) & (1 << 7)))
  35                 cpu_relax();
  36
  37         iomd_writeb(val, IOMD_KARTTX);
  38
  39         return 0;
  40 }
  41
  42 static irqreturn_t rpckbd_rx(int irq, void *dev_id)
  43 {
  44         struct serio *port = dev_id;
  45         unsigned int byte;
  46         int handled = IRQ_NONE;
  47
  48         while (iomd_readb(IOMD_KCTRL) & (1 << 5)) {
  49                 byte = iomd_readb(IOMD_KARTRX);
  50
  51                 serio_interrupt(port, byte, 0);
  52                 handled = IRQ_HANDLED;
  53         }
  54         return handled;
  55 }
  56
  57 static irqreturn_t rpckbd_tx(int irq, void *dev_id)
  58 {
  59         return IRQ_HANDLED;
  60 }
  61
  62 static int rpckbd_open(struct serio *port)
  63 {
  64         struct rpckbd_data *rpckbd = port->port_data;
  65
  66         /* Reset the keyboard state machine. */
  67         iomd_writeb(0, IOMD_KCTRL);
  68         iomd_writeb(8, IOMD_KCTRL);
  69         iomd_readb(IOMD_KARTRX);
  70
  71         if (request_irq(rpckbd->rx_irq, rpckbd_rx, 0, "rpckbd", port) != 0) {
  72                 printk(KERN_ERR "rpckbd.c: Could not allocate keyboard receive IRQ\n");
  73                 return -EBUSY;
  74         }
  75
  76         if (request_irq(rpckbd->tx_irq, rpckbd_tx, 0, "rpckbd", port) != 0) {
  77                 printk(KERN_ERR "rpckbd.c: Could not allocate keyboard transmit IRQ\n");
  78                 free_irq(rpckbd->rx_irq, port);
  79                 return -EBUSY;
  80         }
  81
  82         return 0;
  83 }
  84
  85 static void rpckbd_close(struct serio *port)
  86 {
  87         struct rpckbd_data *rpckbd = port->port_data;
  88
  89         free_irq(rpckbd->rx_irq, port);
  90         free_irq(rpckbd->tx_irq, port);
  91 }
  92
  93 /*
  94  * Allocate and initialize serio structure for subsequent registration
  95  * with serio core.
  96  */
  97 static int rpckbd_probe(struct platform_device *dev)
  98 {
  99         struct rpckbd_data *rpckbd;
 100         struct serio *serio;
 101         int tx_irq, rx_irq;
 102
 103         rx_irq = platform_get_irq(dev, 0);
 104         if (rx_irq < 0)
 105                 return rx_irq;
 106
 107         tx_irq = platform_get_irq(dev, 1);
 108         if (tx_irq < 0)
 109                 return tx_irq;
 110
 111         serio = kzalloc(sizeof(*serio), GFP_KERNEL);
 112         rpckbd = kzalloc(sizeof(*rpckbd), GFP_KERNEL);
 113         if (!serio || !rpckbd) {
 114                 kfree(rpckbd);
 115                 kfree(serio);
 116                 return -ENOMEM;
 117         }
 118
 119         rpckbd->rx_irq = rx_irq;
 120         rpckbd->tx_irq = tx_irq;
 121
 122         serio->id.type          = SERIO_8042;
 123         serio->write            = rpckbd_write;
 124         serio->open             = rpckbd_open;
 125         serio->close            = rpckbd_close;
 126         serio->dev.parent       = &dev->dev;
 127         serio->port_data        = rpckbd;
 128         strscpy(serio->name, "RiscPC PS/2 kbd port", sizeof(serio->name));
 129         strscpy(serio->phys, "rpckbd/serio0", sizeof(serio->phys));
 130
 131         platform_set_drvdata(dev, serio);
 132         serio_register_port(serio);
 133         return 0;
 134 }
 135
 136 static void rpckbd_remove(struct platform_device *dev)
 137 {
 138         struct serio *serio = platform_get_drvdata(dev);
 139         struct rpckbd_data *rpckbd = serio->port_data;
 140
 141         serio_unregister_port(serio);
 142         kfree(rpckbd);
 143 }
 144
 145 static struct platform_driver rpckbd_driver = {
 146         .probe          = rpckbd_probe,
 147         .remove         = rpckbd_remove,
 148         .driver         = {
 149                 .name   = "kart",
 150         },
 151 };
 152 module_platform_driver(rpckbd_driver);