1/* 2 * linux/drivers/input/serio/ambakmi.c 3 * 4 * Copyright (C) 2000-2003 Deep Blue Solutions Ltd. 5 * Copyright (C) 2002 Russell King. 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 */ 12#include <linux/module.h> 13#include <linux/init.h> 14#include <linux/serio.h> 15#include <linux/errno.h> 16#include <linux/interrupt.h> 17#include <linux/ioport.h> 18#include <linux/device.h> 19#include <linux/delay.h> 20#include <linux/slab.h> 21#include <linux/err.h> 22#include <linux/amba/bus.h> 23#include <linux/amba/kmi.h> 24#include <linux/clk.h> 25 26#include <asm/io.h> 27#include <asm/irq.h> 28 29#define KMI_BASE (kmi->base) 30 31struct amba_kmi_port { 32 struct serio *io; 33 struct clk *clk; 34 void __iomem *base; 35 unsigned int irq; 36 unsigned int divisor; 37 unsigned int open; 38}; 39 40static irqreturn_t amba_kmi_int(int irq, void *dev_id) 41{ 42 struct amba_kmi_port *kmi = dev_id; 43 unsigned int status = readb(KMIIR); 44 int handled = IRQ_NONE; 45 46 while (status & KMIIR_RXINTR) { 47 serio_interrupt(kmi->io, readb(KMIDATA), 0); 48 status = readb(KMIIR); 49 handled = IRQ_HANDLED; 50 } 51 52 return handled; 53} 54 55static int amba_kmi_write(struct serio *io, unsigned char val) 56{ 57 struct amba_kmi_port *kmi = io->port_data; 58 unsigned int timeleft = 10000; /* timeout in 100ms */ 59 60 while ((readb(KMISTAT) & KMISTAT_TXEMPTY) == 0 && --timeleft) 61 udelay(10); 62 63 if (timeleft) 64 writeb(val, KMIDATA); 65 66 return timeleft ? 0 : SERIO_TIMEOUT; 67} 68 69static int amba_kmi_open(struct serio *io) 70{ 71 struct amba_kmi_port *kmi = io->port_data; 72 unsigned int divisor; 73 int ret; 74 75 ret = clk_enable(kmi->clk); 76 if (ret) 77 goto out; 78 79 divisor = clk_get_rate(kmi->clk) / 8000000 - 1; 80 writeb(divisor, KMICLKDIV); 81 writeb(KMICR_EN, KMICR); 82 83 ret = request_irq(kmi->irq, amba_kmi_int, 0, "kmi-pl050", kmi); 84 if (ret) { 85 printk(KERN_ERR "kmi: failed to claim IRQ%d\n", kmi->irq); 86 writeb(0, KMICR); 87 goto clk_disable; 88 } 89 90 writeb(KMICR_EN | KMICR_RXINTREN, KMICR); 91 92 return 0; 93 94 clk_disable: 95 clk_disable(kmi->clk); 96 out: 97 return ret; 98} 99 100static void amba_kmi_close(struct serio *io) 101{ 102 struct amba_kmi_port *kmi = io->port_data; 103 104 writeb(0, KMICR); 105 106 free_irq(kmi->irq, kmi); 107 clk_disable(kmi->clk); 108} 109 110static int __devinit amba_kmi_probe(struct amba_device *dev, struct amba_id *id) 111{ 112 struct amba_kmi_port *kmi; 113 struct serio *io; 114 int ret; 115 116 ret = amba_request_regions(dev, NULL); 117 if (ret) 118 return ret; 119 120 kmi = kzalloc(sizeof(struct amba_kmi_port), GFP_KERNEL); 121 io = kzalloc(sizeof(struct serio), GFP_KERNEL); 122 if (!kmi || !io) { 123 ret = -ENOMEM; 124 goto out; 125 } 126 127 128 io->id.type = SERIO_8042; 129 io->write = amba_kmi_write; 130 io->open = amba_kmi_open; 131 io->close = amba_kmi_close; 132 strlcpy(io->name, dev_name(&dev->dev), sizeof(io->name)); 133 strlcpy(io->phys, dev_name(&dev->dev), sizeof(io->phys)); 134 io->port_data = kmi; 135 io->dev.parent = &dev->dev; 136 137 kmi->io = io; 138 kmi->base = ioremap(dev->res.start, resource_size(&dev->res)); 139 if (!kmi->base) { 140 ret = -ENOMEM; 141 goto out; 142 } 143 144 kmi->clk = clk_get(&dev->dev, "KMIREFCLK"); 145 if (IS_ERR(kmi->clk)) { 146 ret = PTR_ERR(kmi->clk); 147 goto unmap; 148 } 149 150 kmi->irq = dev->irq[0]; 151 amba_set_drvdata(dev, kmi); 152 153 serio_register_port(kmi->io); 154 return 0; 155 156 unmap: 157 iounmap(kmi->base); 158 out: 159 kfree(kmi); 160 kfree(io); 161 amba_release_regions(dev); 162 return ret; 163} 164 165static int __devexit amba_kmi_remove(struct amba_device *dev) 166{ 167 struct amba_kmi_port *kmi = amba_get_drvdata(dev); 168 169 amba_set_drvdata(dev, NULL); 170 171 serio_unregister_port(kmi->io); 172 clk_put(kmi->clk); 173 iounmap(kmi->base); 174 kfree(kmi); 175 amba_release_regions(dev); 176 return 0; 177} 178 179static int amba_kmi_resume(struct amba_device *dev) 180{ 181 struct amba_kmi_port *kmi = amba_get_drvdata(dev); 182 183 /* kick the serio layer to rescan this port */ 184 serio_reconnect(kmi->io); 185 186 return 0; 187} 188 189static struct amba_id amba_kmi_idtable[] = { 190 { 191 .id = 0x00041050, 192 .mask = 0x000fffff, 193 }, 194 { 0, 0 } 195}; 196 197static struct amba_driver ambakmi_driver = { 198 .drv = { 199 .name = "kmi-pl050", 200 .owner = THIS_MODULE, 201 }, 202 .id_table = amba_kmi_idtable, 203 .probe = amba_kmi_probe, 204 .remove = __devexit_p(amba_kmi_remove), 205 .resume = amba_kmi_resume, 206}; 207 208static int __init amba_kmi_init(void) 209{ 210 return amba_driver_register(&ambakmi_driver); 211} 212 213static void __exit amba_kmi_exit(void) 214{ 215 amba_driver_unregister(&ambakmi_driver); 216} 217 218module_init(amba_kmi_init); 219module_exit(amba_kmi_exit); 220 221MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>"); 222MODULE_DESCRIPTION("AMBA KMI controller driver"); 223MODULE_LICENSE("GPL"); 224