1 /* 2 * linux/drivers/input/serio/sa1111ps2.c 3 * 4 * Copyright (C) 2002 Russell King 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License. 9 */ 10 #include <linux/module.h> 11 #include <linux/init.h> 12 #include <linux/input.h> 13 #include <linux/serio.h> 14 #include <linux/errno.h> 15 #include <linux/interrupt.h> 16 #include <linux/ioport.h> 17 #include <linux/delay.h> 18 #include <linux/device.h> 19 #include <linux/slab.h> 20 #include <linux/spinlock.h> 21 22 #include <asm/io.h> 23 #include <asm/irq.h> 24 #include <asm/system.h> 25 26 #include <asm/hardware/sa1111.h> 27 28 struct ps2if { 29 struct serio *io; 30 struct sa1111_dev *dev; 31 void __iomem *base; 32 unsigned int open; 33 spinlock_t lock; 34 unsigned int head; 35 unsigned int tail; 36 unsigned char buf[4]; 37 }; 38 39 /* 40 * Read all bytes waiting in the PS2 port. There should be 41 * at the most one, but we loop for safety. If there was a 42 * framing error, we have to manually clear the status. 43 */ 44 static irqreturn_t ps2_rxint(int irq, void *dev_id, struct pt_regs *regs) 45 { 46 struct ps2if *ps2if = dev_id; 47 unsigned int scancode, flag, status; 48 49 status = sa1111_readl(ps2if->base + SA1111_PS2STAT); 50 while (status & PS2STAT_RXF) { 51 if (status & PS2STAT_STP) 52 sa1111_writel(PS2STAT_STP, ps2if->base + SA1111_PS2STAT); 53 54 flag = (status & PS2STAT_STP ? SERIO_FRAME : 0) | 55 (status & PS2STAT_RXP ? 0 : SERIO_PARITY); 56 57 scancode = sa1111_readl(ps2if->base + SA1111_PS2DATA) & 0xff; 58 59 if (hweight8(scancode) & 1) 60 flag ^= SERIO_PARITY; 61 62 serio_interrupt(ps2if->io, scancode, flag, regs); 63 64 status = sa1111_readl(ps2if->base + SA1111_PS2STAT); 65 } 66 67 return IRQ_HANDLED; 68 } 69 70 /* 71 * Completion of ps2 write 72 */ 73 static irqreturn_t ps2_txint(int irq, void *dev_id, struct pt_regs *regs) 74 { 75 struct ps2if *ps2if = dev_id; 76 unsigned int status; 77 78 spin_lock(&ps2if->lock); 79 status = sa1111_readl(ps2if->base + SA1111_PS2STAT); 80 if (ps2if->head == ps2if->tail) { 81 disable_irq(irq); 82 /* done */ 83 } else if (status & PS2STAT_TXE) { 84 sa1111_writel(ps2if->buf[ps2if->tail], ps2if->base + SA1111_PS2DATA); 85 ps2if->tail = (ps2if->tail + 1) & (sizeof(ps2if->buf) - 1); 86 } 87 spin_unlock(&ps2if->lock); 88 89 return IRQ_HANDLED; 90 } 91 92 /* 93 * Write a byte to the PS2 port. We have to wait for the 94 * port to indicate that the transmitter is empty. 95 */ 96 static int ps2_write(struct serio *io, unsigned char val) 97 { 98 struct ps2if *ps2if = io->port_data; 99 unsigned long flags; 100 unsigned int head; 101 102 spin_lock_irqsave(&ps2if->lock, flags); 103 104 /* 105 * If the TX register is empty, we can go straight out. 106 */ 107 if (sa1111_readl(ps2if->base + SA1111_PS2STAT) & PS2STAT_TXE) { 108 sa1111_writel(val, ps2if->base + SA1111_PS2DATA); 109 } else { 110 if (ps2if->head == ps2if->tail) 111 enable_irq(ps2if->dev->irq[1]); 112 head = (ps2if->head + 1) & (sizeof(ps2if->buf) - 1); 113 if (head != ps2if->tail) { 114 ps2if->buf[ps2if->head] = val; 115 ps2if->head = head; 116 } 117 } 118 119 spin_unlock_irqrestore(&ps2if->lock, flags); 120 return 0; 121 } 122 123 static int ps2_open(struct serio *io) 124 { 125 struct ps2if *ps2if = io->port_data; 126 int ret; 127 128 sa1111_enable_device(ps2if->dev); 129 130 ret = request_irq(ps2if->dev->irq[0], ps2_rxint, 0, 131 SA1111_DRIVER_NAME(ps2if->dev), ps2if); 132 if (ret) { 133 printk(KERN_ERR "sa1111ps2: could not allocate IRQ%d: %d\n", 134 ps2if->dev->irq[0], ret); 135 return ret; 136 } 137 138 ret = request_irq(ps2if->dev->irq[1], ps2_txint, 0, 139 SA1111_DRIVER_NAME(ps2if->dev), ps2if); 140 if (ret) { 141 printk(KERN_ERR "sa1111ps2: could not allocate IRQ%d: %d\n", 142 ps2if->dev->irq[1], ret); 143 free_irq(ps2if->dev->irq[0], ps2if); 144 return ret; 145 } 146 147 ps2if->open = 1; 148 149 enable_irq_wake(ps2if->dev->irq[0]); 150 151 sa1111_writel(PS2CR_ENA, ps2if->base + SA1111_PS2CR); 152 return 0; 153 } 154 155 static void ps2_close(struct serio *io) 156 { 157 struct ps2if *ps2if = io->port_data; 158 159 sa1111_writel(0, ps2if->base + SA1111_PS2CR); 160 161 disable_irq_wake(ps2if->dev->irq[0]); 162 163 ps2if->open = 0; 164 165 free_irq(ps2if->dev->irq[1], ps2if); 166 free_irq(ps2if->dev->irq[0], ps2if); 167 168 sa1111_disable_device(ps2if->dev); 169 } 170 171 /* 172 * Clear the input buffer. 173 */ 174 static void __init ps2_clear_input(struct ps2if *ps2if) 175 { 176 int maxread = 100; 177 178 while (maxread--) { 179 if ((sa1111_readl(ps2if->base + SA1111_PS2DATA) & 0xff) == 0xff) 180 break; 181 } 182 } 183 184 static inline unsigned int 185 ps2_test_one(struct ps2if *ps2if, unsigned int mask) 186 { 187 unsigned int val; 188 189 sa1111_writel(PS2CR_ENA | mask, ps2if->base + SA1111_PS2CR); 190 191 udelay(2); 192 193 val = sa1111_readl(ps2if->base + SA1111_PS2STAT); 194 return val & (PS2STAT_KBC | PS2STAT_KBD); 195 } 196 197 /* 198 * Test the keyboard interface. We basically check to make sure that 199 * we can drive each line to the keyboard independently of each other. 200 */ 201 static int __init ps2_test(struct ps2if *ps2if) 202 { 203 unsigned int stat; 204 int ret = 0; 205 206 stat = ps2_test_one(ps2if, PS2CR_FKC); 207 if (stat != PS2STAT_KBD) { 208 printk("PS/2 interface test failed[1]: %02x\n", stat); 209 ret = -ENODEV; 210 } 211 212 stat = ps2_test_one(ps2if, 0); 213 if (stat != (PS2STAT_KBC | PS2STAT_KBD)) { 214 printk("PS/2 interface test failed[2]: %02x\n", stat); 215 ret = -ENODEV; 216 } 217 218 stat = ps2_test_one(ps2if, PS2CR_FKD); 219 if (stat != PS2STAT_KBC) { 220 printk("PS/2 interface test failed[3]: %02x\n", stat); 221 ret = -ENODEV; 222 } 223 224 sa1111_writel(0, ps2if->base + SA1111_PS2CR); 225 226 return ret; 227 } 228 229 /* 230 * Add one device to this driver. 231 */ 232 static int ps2_probe(struct sa1111_dev *dev) 233 { 234 struct ps2if *ps2if; 235 struct serio *serio; 236 int ret; 237 238 ps2if = kmalloc(sizeof(struct ps2if), GFP_KERNEL); 239 serio = kmalloc(sizeof(struct serio), GFP_KERNEL); 240 if (!ps2if || !serio) { 241 ret = -ENOMEM; 242 goto free; 243 } 244 245 memset(ps2if, 0, sizeof(struct ps2if)); 246 memset(serio, 0, sizeof(struct serio)); 247 248 serio->id.type = SERIO_8042; 249 serio->write = ps2_write; 250 serio->open = ps2_open; 251 serio->close = ps2_close; 252 strlcpy(serio->name, dev->dev.bus_id, sizeof(serio->name)); 253 strlcpy(serio->phys, dev->dev.bus_id, sizeof(serio->phys)); 254 serio->port_data = ps2if; 255 serio->dev.parent = &dev->dev; 256 ps2if->io = serio; 257 ps2if->dev = dev; 258 sa1111_set_drvdata(dev, ps2if); 259 260 spin_lock_init(&ps2if->lock); 261 262 /* 263 * Request the physical region for this PS2 port. 264 */ 265 if (!request_mem_region(dev->res.start, 266 dev->res.end - dev->res.start + 1, 267 SA1111_DRIVER_NAME(dev))) { 268 ret = -EBUSY; 269 goto free; 270 } 271 272 /* 273 * Our parent device has already mapped the region. 274 */ 275 ps2if->base = dev->mapbase; 276 277 sa1111_enable_device(ps2if->dev); 278 279 /* Incoming clock is 8MHz */ 280 sa1111_writel(0, ps2if->base + SA1111_PS2CLKDIV); 281 sa1111_writel(127, ps2if->base + SA1111_PS2PRECNT); 282 283 /* 284 * Flush any pending input. 285 */ 286 ps2_clear_input(ps2if); 287 288 /* 289 * Test the keyboard interface. 290 */ 291 ret = ps2_test(ps2if); 292 if (ret) 293 goto out; 294 295 /* 296 * Flush any pending input. 297 */ 298 ps2_clear_input(ps2if); 299 300 sa1111_disable_device(ps2if->dev); 301 serio_register_port(ps2if->io); 302 return 0; 303 304 out: 305 sa1111_disable_device(ps2if->dev); 306 release_mem_region(dev->res.start, 307 dev->res.end - dev->res.start + 1); 308 free: 309 sa1111_set_drvdata(dev, NULL); 310 kfree(ps2if); 311 kfree(serio); 312 return ret; 313 } 314 315 /* 316 * Remove one device from this driver. 317 */ 318 static int ps2_remove(struct sa1111_dev *dev) 319 { 320 struct ps2if *ps2if = sa1111_get_drvdata(dev); 321 322 serio_unregister_port(ps2if->io); 323 release_mem_region(dev->res.start, 324 dev->res.end - dev->res.start + 1); 325 sa1111_set_drvdata(dev, NULL); 326 327 kfree(ps2if); 328 329 return 0; 330 } 331 332 /* 333 * Our device driver structure 334 */ 335 static struct sa1111_driver ps2_driver = { 336 .drv = { 337 .name = "sa1111-ps2", 338 }, 339 .devid = SA1111_DEVID_PS2, 340 .probe = ps2_probe, 341 .remove = ps2_remove, 342 }; 343 344 static int __init ps2_init(void) 345 { 346 return sa1111_driver_register(&ps2_driver); 347 } 348 349 static void __exit ps2_exit(void) 350 { 351 sa1111_driver_unregister(&ps2_driver); 352 } 353 354 module_init(ps2_init); 355 module_exit(ps2_exit); 356 357 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>"); 358 MODULE_DESCRIPTION("SA1111 PS2 controller driver"); 359 MODULE_LICENSE("GPL"); 360