1 /* 2 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * Driver is originally developed by Pavel Sokolov <psokolov@synopsys.com> 9 */ 10 11 #include <linux/module.h> 12 #include <linux/interrupt.h> 13 #include <linux/input.h> 14 #include <linux/serio.h> 15 #include <linux/platform_device.h> 16 #include <linux/io.h> 17 #include <linux/kernel.h> 18 #include <linux/slab.h> 19 20 #define ARC_PS2_PORTS 2 21 22 #define ARC_ARC_PS2_ID 0x0001f609 23 24 #define STAT_TIMEOUT 128 25 26 #define PS2_STAT_RX_FRM_ERR (1) 27 #define PS2_STAT_RX_BUF_OVER (1 << 1) 28 #define PS2_STAT_RX_INT_EN (1 << 2) 29 #define PS2_STAT_RX_VAL (1 << 3) 30 #define PS2_STAT_TX_ISNOT_FUL (1 << 4) 31 #define PS2_STAT_TX_INT_EN (1 << 5) 32 33 struct arc_ps2_port { 34 void __iomem *data_addr; 35 void __iomem *status_addr; 36 struct serio *io; 37 }; 38 39 struct arc_ps2_data { 40 struct arc_ps2_port port[ARC_PS2_PORTS]; 41 void __iomem *addr; 42 unsigned int frame_error; 43 unsigned int buf_overflow; 44 unsigned int total_int; 45 }; 46 47 static void arc_ps2_check_rx(struct arc_ps2_data *arc_ps2, 48 struct arc_ps2_port *port) 49 { 50 unsigned int timeout = 1000; 51 unsigned int flag, status; 52 unsigned char data; 53 54 do { 55 status = ioread32(port->status_addr); 56 if (!(status & PS2_STAT_RX_VAL)) 57 return; 58 59 data = ioread32(port->data_addr) & 0xff; 60 61 flag = 0; 62 arc_ps2->total_int++; 63 if (status & PS2_STAT_RX_FRM_ERR) { 64 arc_ps2->frame_error++; 65 flag |= SERIO_PARITY; 66 } else if (status & PS2_STAT_RX_BUF_OVER) { 67 arc_ps2->buf_overflow++; 68 flag |= SERIO_FRAME; 69 } 70 71 serio_interrupt(port->io, data, flag); 72 } while (--timeout); 73 74 dev_err(&port->io->dev, "PS/2 hardware stuck\n"); 75 } 76 77 static irqreturn_t arc_ps2_interrupt(int irq, void *dev) 78 { 79 struct arc_ps2_data *arc_ps2 = dev; 80 int i; 81 82 for (i = 0; i < ARC_PS2_PORTS; i++) 83 arc_ps2_check_rx(arc_ps2, &arc_ps2->port[i]); 84 85 return IRQ_HANDLED; 86 } 87 88 static int arc_ps2_write(struct serio *io, unsigned char val) 89 { 90 unsigned status; 91 struct arc_ps2_port *port = io->port_data; 92 int timeout = STAT_TIMEOUT; 93 94 do { 95 status = ioread32(port->status_addr); 96 cpu_relax(); 97 98 if (status & PS2_STAT_TX_ISNOT_FUL) { 99 iowrite32(val & 0xff, port->data_addr); 100 return 0; 101 } 102 103 } while (--timeout); 104 105 dev_err(&io->dev, "write timeout\n"); 106 return -ETIMEDOUT; 107 } 108 109 static int arc_ps2_open(struct serio *io) 110 { 111 struct arc_ps2_port *port = io->port_data; 112 113 iowrite32(PS2_STAT_RX_INT_EN, port->status_addr); 114 115 return 0; 116 } 117 118 static void arc_ps2_close(struct serio *io) 119 { 120 struct arc_ps2_port *port = io->port_data; 121 122 iowrite32(ioread32(port->status_addr) & ~PS2_STAT_RX_INT_EN, 123 port->status_addr); 124 } 125 126 static void __iomem *arc_ps2_calc_addr(struct arc_ps2_data *arc_ps2, 127 int index, bool status) 128 { 129 void __iomem *addr; 130 131 addr = arc_ps2->addr + 4 + 4 * index; 132 if (status) 133 addr += ARC_PS2_PORTS * 4; 134 135 return addr; 136 } 137 138 static void arc_ps2_inhibit_ports(struct arc_ps2_data *arc_ps2) 139 { 140 void __iomem *addr; 141 u32 val; 142 int i; 143 144 for (i = 0; i < ARC_PS2_PORTS; i++) { 145 addr = arc_ps2_calc_addr(arc_ps2, i, true); 146 val = ioread32(addr); 147 val &= ~(PS2_STAT_RX_INT_EN | PS2_STAT_TX_INT_EN); 148 iowrite32(val, addr); 149 } 150 } 151 152 static int arc_ps2_create_port(struct platform_device *pdev, 153 struct arc_ps2_data *arc_ps2, 154 int index) 155 { 156 struct arc_ps2_port *port = &arc_ps2->port[index]; 157 struct serio *io; 158 159 io = kzalloc(sizeof(struct serio), GFP_KERNEL); 160 if (!io) 161 return -ENOMEM; 162 163 io->id.type = SERIO_8042; 164 io->write = arc_ps2_write; 165 io->open = arc_ps2_open; 166 io->close = arc_ps2_close; 167 snprintf(io->name, sizeof(io->name), "ARC PS/2 port%d", index); 168 snprintf(io->phys, sizeof(io->phys), "arc/serio%d", index); 169 io->port_data = port; 170 171 port->io = io; 172 173 port->data_addr = arc_ps2_calc_addr(arc_ps2, index, false); 174 port->status_addr = arc_ps2_calc_addr(arc_ps2, index, true); 175 176 dev_dbg(&pdev->dev, "port%d is allocated (data = 0x%p, status = 0x%p)\n", 177 index, port->data_addr, port->status_addr); 178 179 serio_register_port(port->io); 180 return 0; 181 } 182 183 static int arc_ps2_probe(struct platform_device *pdev) 184 { 185 struct arc_ps2_data *arc_ps2; 186 struct resource *res; 187 int irq; 188 int error, id, i; 189 190 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 191 if (!res) { 192 dev_err(&pdev->dev, "no IO memory defined\n"); 193 return -EINVAL; 194 } 195 196 irq = platform_get_irq_byname(pdev, "arc_ps2_irq"); 197 if (irq < 0) { 198 dev_err(&pdev->dev, "no IRQ defined\n"); 199 return -EINVAL; 200 } 201 202 arc_ps2 = devm_kzalloc(&pdev->dev, sizeof(struct arc_ps2_data), 203 GFP_KERNEL); 204 if (!arc_ps2) { 205 dev_err(&pdev->dev, "out of memory\n"); 206 return -ENOMEM; 207 } 208 209 arc_ps2->addr = devm_request_and_ioremap(&pdev->dev, res); 210 if (!arc_ps2->addr) 211 return -EBUSY; 212 213 dev_info(&pdev->dev, "irq = %d, address = 0x%p, ports = %i\n", 214 irq, arc_ps2->addr, ARC_PS2_PORTS); 215 216 id = ioread32(arc_ps2->addr); 217 if (id != ARC_ARC_PS2_ID) { 218 dev_err(&pdev->dev, "device id does not match\n"); 219 return -ENXIO; 220 } 221 222 arc_ps2_inhibit_ports(arc_ps2); 223 224 error = devm_request_irq(&pdev->dev, irq, arc_ps2_interrupt, 225 0, "arc_ps2", arc_ps2); 226 if (error) { 227 dev_err(&pdev->dev, "Could not allocate IRQ\n"); 228 return error; 229 } 230 231 for (i = 0; i < ARC_PS2_PORTS; i++) { 232 error = arc_ps2_create_port(pdev, arc_ps2, i); 233 if (error) { 234 while (--i >= 0) 235 serio_unregister_port(arc_ps2->port[i].io); 236 return error; 237 } 238 } 239 240 platform_set_drvdata(pdev, arc_ps2); 241 242 return 0; 243 } 244 245 static int arc_ps2_remove(struct platform_device *pdev) 246 { 247 struct arc_ps2_data *arc_ps2 = platform_get_drvdata(pdev); 248 int i; 249 250 for (i = 0; i < ARC_PS2_PORTS; i++) 251 serio_unregister_port(arc_ps2->port[i].io); 252 253 dev_dbg(&pdev->dev, "interrupt count = %i\n", arc_ps2->total_int); 254 dev_dbg(&pdev->dev, "frame error count = %i\n", arc_ps2->frame_error); 255 dev_dbg(&pdev->dev, "buffer overflow count = %i\n", 256 arc_ps2->buf_overflow); 257 258 return 0; 259 } 260 261 static struct platform_driver arc_ps2_driver = { 262 .driver = { 263 .name = "arc_ps2", 264 .owner = THIS_MODULE, 265 }, 266 .probe = arc_ps2_probe, 267 .remove = arc_ps2_remove, 268 }; 269 270 module_platform_driver(arc_ps2_driver); 271 272 MODULE_LICENSE("GPL"); 273 MODULE_AUTHOR("Pavel Sokolov <psokolov@synopsys.com>"); 274 MODULE_DESCRIPTION("ARC PS/2 Driver"); 275