Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Uwe Zeisberger | f30c226 | 2006-10-03 23:01:26 +0200 | [diff] [blame] | 2 | * drivers/i2c/busses/i2c-ibm_iic.c |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3 | * |
| 4 | * Support for the IIC peripheral on IBM PPC 4xx |
| 5 | * |
| 6 | * Copyright (c) 2003, 2004 Zultys Technologies. |
| 7 | * Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net> |
| 8 | * |
Sean MacLennan | 838349b | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 9 | * Copyright (c) 2008 PIKA Technologies |
| 10 | * Sean MacLennan <smaclennan@pikatech.com> |
| 11 | * |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 12 | * Based on original work by |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | * Ian DaSilva <idasilva@mvista.com> |
| 14 | * Armin Kuster <akuster@mvista.com> |
| 15 | * Matt Porter <mporter@mvista.com> |
| 16 | * |
| 17 | * Copyright 2000-2003 MontaVista Software Inc. |
| 18 | * |
| 19 | * Original driver version was highly leveraged from i2c-elektor.c |
| 20 | * |
| 21 | * Copyright 1995-97 Simon G. Vogl |
| 22 | * 1998-99 Hans Berglund |
| 23 | * |
Jan Engelhardt | 96de0e2 | 2007-10-19 23:21:04 +0200 | [diff] [blame] | 24 | * With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | * and even Frodo Looijaard <frodol@dds.nl> |
| 26 | * |
| 27 | * This program is free software; you can redistribute it and/or modify it |
| 28 | * under the terms of the GNU General Public License as published by the |
| 29 | * Free Software Foundation; either version 2 of the License, or (at your |
| 30 | * option) any later version. |
| 31 | * |
| 32 | */ |
| 33 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | #include <linux/module.h> |
| 35 | #include <linux/kernel.h> |
| 36 | #include <linux/ioport.h> |
| 37 | #include <linux/delay.h> |
| 38 | #include <linux/slab.h> |
| 39 | #include <linux/init.h> |
| 40 | #include <linux/interrupt.h> |
| 41 | #include <asm/irq.h> |
| 42 | #include <asm/io.h> |
| 43 | #include <linux/i2c.h> |
| 44 | #include <linux/i2c-id.h> |
Sean MacLennan | 838349b | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 45 | #include <linux/of_platform.h> |
Sean MacLennan | b1204e6 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 46 | #include <linux/of_i2c.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | |
| 48 | #include "i2c-ibm_iic.h" |
| 49 | |
Sean MacLennan | 838349b | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 50 | #define DRIVER_VERSION "2.2" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | |
| 52 | MODULE_DESCRIPTION("IBM IIC driver v" DRIVER_VERSION); |
| 53 | MODULE_LICENSE("GPL"); |
| 54 | |
| 55 | static int iic_force_poll; |
| 56 | module_param(iic_force_poll, bool, 0); |
| 57 | MODULE_PARM_DESC(iic_force_poll, "Force polling mode"); |
| 58 | |
| 59 | static int iic_force_fast; |
| 60 | module_param(iic_force_fast, bool, 0); |
Paul Mundt | 852fb2a | 2008-04-11 12:07:04 +0200 | [diff] [blame] | 61 | MODULE_PARM_DESC(iic_force_fast, "Force fast mode (400 kHz)"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | |
| 63 | #define DBG_LEVEL 0 |
| 64 | |
| 65 | #ifdef DBG |
| 66 | #undef DBG |
| 67 | #endif |
| 68 | |
| 69 | #ifdef DBG2 |
| 70 | #undef DBG2 |
| 71 | #endif |
| 72 | |
| 73 | #if DBG_LEVEL > 0 |
| 74 | # define DBG(f,x...) printk(KERN_DEBUG "ibm-iic" f, ##x) |
| 75 | #else |
| 76 | # define DBG(f,x...) ((void)0) |
| 77 | #endif |
| 78 | #if DBG_LEVEL > 1 |
| 79 | # define DBG2(f,x...) DBG(f, ##x) |
| 80 | #else |
| 81 | # define DBG2(f,x...) ((void)0) |
| 82 | #endif |
| 83 | #if DBG_LEVEL > 2 |
| 84 | static void dump_iic_regs(const char* header, struct ibm_iic_private* dev) |
| 85 | { |
| 86 | volatile struct iic_regs __iomem *iic = dev->vaddr; |
| 87 | printk(KERN_DEBUG "ibm-iic%d: %s\n", dev->idx, header); |
| 88 | printk(KERN_DEBUG " cntl = 0x%02x, mdcntl = 0x%02x\n" |
| 89 | KERN_DEBUG " sts = 0x%02x, extsts = 0x%02x\n" |
| 90 | KERN_DEBUG " clkdiv = 0x%02x, xfrcnt = 0x%02x\n" |
| 91 | KERN_DEBUG " xtcntlss = 0x%02x, directcntl = 0x%02x\n", |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 92 | in_8(&iic->cntl), in_8(&iic->mdcntl), in_8(&iic->sts), |
| 93 | in_8(&iic->extsts), in_8(&iic->clkdiv), in_8(&iic->xfrcnt), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | in_8(&iic->xtcntlss), in_8(&iic->directcntl)); |
| 95 | } |
| 96 | # define DUMP_REGS(h,dev) dump_iic_regs((h),(dev)) |
| 97 | #else |
| 98 | # define DUMP_REGS(h,dev) ((void)0) |
| 99 | #endif |
| 100 | |
| 101 | /* Bus timings (in ns) for bit-banging */ |
| 102 | static struct i2c_timings { |
| 103 | unsigned int hd_sta; |
| 104 | unsigned int su_sto; |
| 105 | unsigned int low; |
| 106 | unsigned int high; |
| 107 | unsigned int buf; |
| 108 | } timings [] = { |
| 109 | /* Standard mode (100 KHz) */ |
| 110 | { |
| 111 | .hd_sta = 4000, |
| 112 | .su_sto = 4000, |
| 113 | .low = 4700, |
| 114 | .high = 4000, |
| 115 | .buf = 4700, |
| 116 | }, |
| 117 | /* Fast mode (400 KHz) */ |
| 118 | { |
| 119 | .hd_sta = 600, |
| 120 | .su_sto = 600, |
| 121 | .low = 1300, |
| 122 | .high = 600, |
| 123 | .buf = 1300, |
| 124 | }}; |
| 125 | |
| 126 | /* Enable/disable interrupt generation */ |
| 127 | static inline void iic_interrupt_mode(struct ibm_iic_private* dev, int enable) |
| 128 | { |
| 129 | out_8(&dev->vaddr->intmsk, enable ? INTRMSK_EIMTC : 0); |
| 130 | } |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 131 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | /* |
| 133 | * Initialize IIC interface. |
| 134 | */ |
| 135 | static void iic_dev_init(struct ibm_iic_private* dev) |
| 136 | { |
| 137 | volatile struct iic_regs __iomem *iic = dev->vaddr; |
| 138 | |
| 139 | DBG("%d: init\n", dev->idx); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 140 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | /* Clear master address */ |
| 142 | out_8(&iic->lmadr, 0); |
| 143 | out_8(&iic->hmadr, 0); |
| 144 | |
| 145 | /* Clear slave address */ |
| 146 | out_8(&iic->lsadr, 0); |
| 147 | out_8(&iic->hsadr, 0); |
| 148 | |
| 149 | /* Clear status & extended status */ |
| 150 | out_8(&iic->sts, STS_SCMP | STS_IRQA); |
| 151 | out_8(&iic->extsts, EXTSTS_IRQP | EXTSTS_IRQD | EXTSTS_LA |
| 152 | | EXTSTS_ICT | EXTSTS_XFRA); |
| 153 | |
| 154 | /* Set clock divider */ |
| 155 | out_8(&iic->clkdiv, dev->clckdiv); |
| 156 | |
| 157 | /* Clear transfer count */ |
| 158 | out_8(&iic->xfrcnt, 0); |
| 159 | |
| 160 | /* Clear extended control and status */ |
| 161 | out_8(&iic->xtcntlss, XTCNTLSS_SRC | XTCNTLSS_SRS | XTCNTLSS_SWC |
| 162 | | XTCNTLSS_SWS); |
| 163 | |
| 164 | /* Clear control register */ |
| 165 | out_8(&iic->cntl, 0); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 166 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | /* Enable interrupts if possible */ |
| 168 | iic_interrupt_mode(dev, dev->irq >= 0); |
| 169 | |
| 170 | /* Set mode control */ |
| 171 | out_8(&iic->mdcntl, MDCNTL_FMDB | MDCNTL_EINT | MDCNTL_EUBS |
| 172 | | (dev->fast_mode ? MDCNTL_FSM : 0)); |
| 173 | |
| 174 | DUMP_REGS("iic_init", dev); |
| 175 | } |
| 176 | |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 177 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | * Reset IIC interface |
| 179 | */ |
| 180 | static void iic_dev_reset(struct ibm_iic_private* dev) |
| 181 | { |
| 182 | volatile struct iic_regs __iomem *iic = dev->vaddr; |
| 183 | int i; |
| 184 | u8 dc; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 185 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 186 | DBG("%d: soft reset\n", dev->idx); |
| 187 | DUMP_REGS("reset", dev); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 188 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | /* Place chip in the reset state */ |
| 190 | out_8(&iic->xtcntlss, XTCNTLSS_SRST); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 191 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | /* Check if bus is free */ |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 193 | dc = in_8(&iic->directcntl); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | if (!DIRCTNL_FREE(dc)){ |
| 195 | DBG("%d: trying to regain bus control\n", dev->idx); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 196 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 197 | /* Try to set bus free state */ |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 198 | out_8(&iic->directcntl, DIRCNTL_SDAC | DIRCNTL_SCC); |
| 199 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | /* Wait until we regain bus control */ |
| 201 | for (i = 0; i < 100; ++i){ |
| 202 | dc = in_8(&iic->directcntl); |
| 203 | if (DIRCTNL_FREE(dc)) |
| 204 | break; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 205 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | /* Toggle SCL line */ |
| 207 | dc ^= DIRCNTL_SCC; |
| 208 | out_8(&iic->directcntl, dc); |
| 209 | udelay(10); |
| 210 | dc ^= DIRCNTL_SCC; |
| 211 | out_8(&iic->directcntl, dc); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 212 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | /* be nice */ |
| 214 | cond_resched(); |
| 215 | } |
| 216 | } |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 217 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 218 | /* Remove reset */ |
| 219 | out_8(&iic->xtcntlss, 0); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 220 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | /* Reinitialize interface */ |
| 222 | iic_dev_init(dev); |
| 223 | } |
| 224 | |
| 225 | /* |
| 226 | * Do 0-length transaction using bit-banging through IIC_DIRECTCNTL register. |
| 227 | */ |
| 228 | |
| 229 | /* Wait for SCL and/or SDA to be high */ |
| 230 | static int iic_dc_wait(volatile struct iic_regs __iomem *iic, u8 mask) |
| 231 | { |
| 232 | unsigned long x = jiffies + HZ / 28 + 2; |
| 233 | while ((in_8(&iic->directcntl) & mask) != mask){ |
| 234 | if (unlikely(time_after(jiffies, x))) |
| 235 | return -1; |
| 236 | cond_resched(); |
| 237 | } |
| 238 | return 0; |
| 239 | } |
| 240 | |
| 241 | static int iic_smbus_quick(struct ibm_iic_private* dev, const struct i2c_msg* p) |
| 242 | { |
| 243 | volatile struct iic_regs __iomem *iic = dev->vaddr; |
| 244 | const struct i2c_timings* t = &timings[dev->fast_mode ? 1 : 0]; |
| 245 | u8 mask, v, sda; |
| 246 | int i, res; |
| 247 | |
| 248 | /* Only 7-bit addresses are supported */ |
| 249 | if (unlikely(p->flags & I2C_M_TEN)){ |
| 250 | DBG("%d: smbus_quick - 10 bit addresses are not supported\n", |
| 251 | dev->idx); |
| 252 | return -EINVAL; |
| 253 | } |
| 254 | |
| 255 | DBG("%d: smbus_quick(0x%02x)\n", dev->idx, p->addr); |
| 256 | |
| 257 | /* Reset IIC interface */ |
| 258 | out_8(&iic->xtcntlss, XTCNTLSS_SRST); |
| 259 | |
| 260 | /* Wait for bus to become free */ |
| 261 | out_8(&iic->directcntl, DIRCNTL_SDAC | DIRCNTL_SCC); |
| 262 | if (unlikely(iic_dc_wait(iic, DIRCNTL_MSDA | DIRCNTL_MSC))) |
| 263 | goto err; |
| 264 | ndelay(t->buf); |
| 265 | |
| 266 | /* START */ |
| 267 | out_8(&iic->directcntl, DIRCNTL_SCC); |
| 268 | sda = 0; |
| 269 | ndelay(t->hd_sta); |
| 270 | |
| 271 | /* Send address */ |
| 272 | v = (u8)((p->addr << 1) | ((p->flags & I2C_M_RD) ? 1 : 0)); |
| 273 | for (i = 0, mask = 0x80; i < 8; ++i, mask >>= 1){ |
| 274 | out_8(&iic->directcntl, sda); |
| 275 | ndelay(t->low / 2); |
| 276 | sda = (v & mask) ? DIRCNTL_SDAC : 0; |
| 277 | out_8(&iic->directcntl, sda); |
| 278 | ndelay(t->low / 2); |
| 279 | |
| 280 | out_8(&iic->directcntl, DIRCNTL_SCC | sda); |
| 281 | if (unlikely(iic_dc_wait(iic, DIRCNTL_MSC))) |
| 282 | goto err; |
| 283 | ndelay(t->high); |
| 284 | } |
| 285 | |
| 286 | /* ACK */ |
| 287 | out_8(&iic->directcntl, sda); |
| 288 | ndelay(t->low / 2); |
| 289 | out_8(&iic->directcntl, DIRCNTL_SDAC); |
| 290 | ndelay(t->low / 2); |
| 291 | out_8(&iic->directcntl, DIRCNTL_SDAC | DIRCNTL_SCC); |
| 292 | if (unlikely(iic_dc_wait(iic, DIRCNTL_MSC))) |
| 293 | goto err; |
| 294 | res = (in_8(&iic->directcntl) & DIRCNTL_MSDA) ? -EREMOTEIO : 1; |
| 295 | ndelay(t->high); |
| 296 | |
| 297 | /* STOP */ |
| 298 | out_8(&iic->directcntl, 0); |
| 299 | ndelay(t->low); |
| 300 | out_8(&iic->directcntl, DIRCNTL_SCC); |
| 301 | if (unlikely(iic_dc_wait(iic, DIRCNTL_MSC))) |
| 302 | goto err; |
| 303 | ndelay(t->su_sto); |
| 304 | out_8(&iic->directcntl, DIRCNTL_SDAC | DIRCNTL_SCC); |
| 305 | |
| 306 | ndelay(t->buf); |
| 307 | |
| 308 | DBG("%d: smbus_quick -> %s\n", dev->idx, res ? "NACK" : "ACK"); |
| 309 | out: |
| 310 | /* Remove reset */ |
| 311 | out_8(&iic->xtcntlss, 0); |
| 312 | |
| 313 | /* Reinitialize interface */ |
| 314 | iic_dev_init(dev); |
| 315 | |
| 316 | return res; |
| 317 | err: |
| 318 | DBG("%d: smbus_quick - bus is stuck\n", dev->idx); |
| 319 | res = -EREMOTEIO; |
| 320 | goto out; |
| 321 | } |
| 322 | |
| 323 | /* |
| 324 | * IIC interrupt handler |
| 325 | */ |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 326 | static irqreturn_t iic_handler(int irq, void *dev_id) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 327 | { |
| 328 | struct ibm_iic_private* dev = (struct ibm_iic_private*)dev_id; |
| 329 | volatile struct iic_regs __iomem *iic = dev->vaddr; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 330 | |
| 331 | DBG2("%d: irq handler, STS = 0x%02x, EXTSTS = 0x%02x\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 332 | dev->idx, in_8(&iic->sts), in_8(&iic->extsts)); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 333 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 334 | /* Acknowledge IRQ and wakeup iic_wait_for_tc */ |
| 335 | out_8(&iic->sts, STS_IRQA | STS_SCMP); |
| 336 | wake_up_interruptible(&dev->wq); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 337 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 338 | return IRQ_HANDLED; |
| 339 | } |
| 340 | |
| 341 | /* |
| 342 | * Get master transfer result and clear errors if any. |
| 343 | * Returns the number of actually transferred bytes or error (<0) |
| 344 | */ |
| 345 | static int iic_xfer_result(struct ibm_iic_private* dev) |
| 346 | { |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 347 | volatile struct iic_regs __iomem *iic = dev->vaddr; |
| 348 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 349 | if (unlikely(in_8(&iic->sts) & STS_ERR)){ |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 350 | DBG("%d: xfer error, EXTSTS = 0x%02x\n", dev->idx, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 351 | in_8(&iic->extsts)); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 352 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 353 | /* Clear errors and possible pending IRQs */ |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 354 | out_8(&iic->extsts, EXTSTS_IRQP | EXTSTS_IRQD | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 355 | EXTSTS_LA | EXTSTS_ICT | EXTSTS_XFRA); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 356 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 357 | /* Flush master data buffer */ |
| 358 | out_8(&iic->mdcntl, in_8(&iic->mdcntl) | MDCNTL_FMDB); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 359 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 360 | /* Is bus free? |
| 361 | * If error happened during combined xfer |
| 362 | * IIC interface is usually stuck in some strange |
| 363 | * state, the only way out - soft reset. |
| 364 | */ |
| 365 | if ((in_8(&iic->extsts) & EXTSTS_BCS_MASK) != EXTSTS_BCS_FREE){ |
| 366 | DBG("%d: bus is stuck, resetting\n", dev->idx); |
| 367 | iic_dev_reset(dev); |
| 368 | } |
| 369 | return -EREMOTEIO; |
| 370 | } |
| 371 | else |
| 372 | return in_8(&iic->xfrcnt) & XFRCNT_MTC_MASK; |
| 373 | } |
| 374 | |
| 375 | /* |
| 376 | * Try to abort active transfer. |
| 377 | */ |
| 378 | static void iic_abort_xfer(struct ibm_iic_private* dev) |
| 379 | { |
| 380 | volatile struct iic_regs __iomem *iic = dev->vaddr; |
| 381 | unsigned long x; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 382 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 383 | DBG("%d: iic_abort_xfer\n", dev->idx); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 384 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 385 | out_8(&iic->cntl, CNTL_HMT); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 386 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 387 | /* |
| 388 | * Wait for the abort command to complete. |
| 389 | * It's not worth to be optimized, just poll (timeout >= 1 tick) |
| 390 | */ |
| 391 | x = jiffies + 2; |
| 392 | while ((in_8(&iic->extsts) & EXTSTS_BCS_MASK) != EXTSTS_BCS_FREE){ |
| 393 | if (time_after(jiffies, x)){ |
| 394 | DBG("%d: abort timeout, resetting...\n", dev->idx); |
| 395 | iic_dev_reset(dev); |
| 396 | return; |
| 397 | } |
| 398 | schedule(); |
| 399 | } |
| 400 | |
| 401 | /* Just to clear errors */ |
| 402 | iic_xfer_result(dev); |
| 403 | } |
| 404 | |
| 405 | /* |
| 406 | * Wait for master transfer to complete. |
| 407 | * It puts current process to sleep until we get interrupt or timeout expires. |
| 408 | * Returns the number of transferred bytes or error (<0) |
| 409 | */ |
| 410 | static int iic_wait_for_tc(struct ibm_iic_private* dev){ |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 411 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 412 | volatile struct iic_regs __iomem *iic = dev->vaddr; |
| 413 | int ret = 0; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 414 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 415 | if (dev->irq >= 0){ |
| 416 | /* Interrupt mode */ |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 417 | ret = wait_event_interruptible_timeout(dev->wq, |
Jean Delvare | 8a52c6b | 2009-03-28 21:34:43 +0100 | [diff] [blame^] | 418 | !(in_8(&iic->sts) & STS_PT), dev->adap.timeout); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 419 | |
| 420 | if (unlikely(ret < 0)) |
| 421 | DBG("%d: wait interrupted\n", dev->idx); |
| 422 | else if (unlikely(in_8(&iic->sts) & STS_PT)){ |
| 423 | DBG("%d: wait timeout\n", dev->idx); |
| 424 | ret = -ETIMEDOUT; |
| 425 | } |
| 426 | } |
| 427 | else { |
| 428 | /* Polling mode */ |
Jean Delvare | 8a52c6b | 2009-03-28 21:34:43 +0100 | [diff] [blame^] | 429 | unsigned long x = jiffies + dev->adap.timeout; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 430 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | while (in_8(&iic->sts) & STS_PT){ |
| 432 | if (unlikely(time_after(jiffies, x))){ |
| 433 | DBG("%d: poll timeout\n", dev->idx); |
| 434 | ret = -ETIMEDOUT; |
| 435 | break; |
| 436 | } |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 437 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 438 | if (unlikely(signal_pending(current))){ |
| 439 | DBG("%d: poll interrupted\n", dev->idx); |
| 440 | ret = -ERESTARTSYS; |
| 441 | break; |
| 442 | } |
| 443 | schedule(); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 444 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 445 | } |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 446 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 447 | if (unlikely(ret < 0)) |
| 448 | iic_abort_xfer(dev); |
| 449 | else |
| 450 | ret = iic_xfer_result(dev); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 451 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 452 | DBG2("%d: iic_wait_for_tc -> %d\n", dev->idx, ret); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 453 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | return ret; |
| 455 | } |
| 456 | |
| 457 | /* |
| 458 | * Low level master transfer routine |
| 459 | */ |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 460 | static int iic_xfer_bytes(struct ibm_iic_private* dev, struct i2c_msg* pm, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 461 | int combined_xfer) |
| 462 | { |
| 463 | volatile struct iic_regs __iomem *iic = dev->vaddr; |
| 464 | char* buf = pm->buf; |
| 465 | int i, j, loops, ret = 0; |
| 466 | int len = pm->len; |
| 467 | |
| 468 | u8 cntl = (in_8(&iic->cntl) & CNTL_AMD) | CNTL_PT; |
| 469 | if (pm->flags & I2C_M_RD) |
| 470 | cntl |= CNTL_RW; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 471 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 472 | loops = (len + 3) / 4; |
| 473 | for (i = 0; i < loops; ++i, len -= 4){ |
| 474 | int count = len > 4 ? 4 : len; |
| 475 | u8 cmd = cntl | ((count - 1) << CNTL_TCT_SHIFT); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 476 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 477 | if (!(cntl & CNTL_RW)) |
| 478 | for (j = 0; j < count; ++j) |
| 479 | out_8((void __iomem *)&iic->mdbuf, *buf++); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 480 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 481 | if (i < loops - 1) |
| 482 | cmd |= CNTL_CHT; |
| 483 | else if (combined_xfer) |
| 484 | cmd |= CNTL_RPST; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 485 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 486 | DBG2("%d: xfer_bytes, %d, CNTL = 0x%02x\n", dev->idx, count, cmd); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 487 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 488 | /* Start transfer */ |
| 489 | out_8(&iic->cntl, cmd); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 490 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 491 | /* Wait for completion */ |
| 492 | ret = iic_wait_for_tc(dev); |
| 493 | |
| 494 | if (unlikely(ret < 0)) |
| 495 | break; |
| 496 | else if (unlikely(ret != count)){ |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 497 | DBG("%d: xfer_bytes, requested %d, transfered %d\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 498 | dev->idx, count, ret); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 499 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 500 | /* If it's not a last part of xfer, abort it */ |
| 501 | if (combined_xfer || (i < loops - 1)) |
| 502 | iic_abort_xfer(dev); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 503 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 504 | ret = -EREMOTEIO; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 505 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | } |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 507 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 508 | if (cntl & CNTL_RW) |
| 509 | for (j = 0; j < count; ++j) |
| 510 | *buf++ = in_8((void __iomem *)&iic->mdbuf); |
| 511 | } |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 512 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 513 | return ret > 0 ? 0 : ret; |
| 514 | } |
| 515 | |
| 516 | /* |
| 517 | * Set target slave address for master transfer |
| 518 | */ |
| 519 | static inline void iic_address(struct ibm_iic_private* dev, struct i2c_msg* msg) |
| 520 | { |
| 521 | volatile struct iic_regs __iomem *iic = dev->vaddr; |
| 522 | u16 addr = msg->addr; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 523 | |
| 524 | DBG2("%d: iic_address, 0x%03x (%d-bit)\n", dev->idx, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 525 | addr, msg->flags & I2C_M_TEN ? 10 : 7); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 526 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 527 | if (msg->flags & I2C_M_TEN){ |
| 528 | out_8(&iic->cntl, CNTL_AMD); |
| 529 | out_8(&iic->lmadr, addr); |
| 530 | out_8(&iic->hmadr, 0xf0 | ((addr >> 7) & 0x06)); |
| 531 | } |
| 532 | else { |
| 533 | out_8(&iic->cntl, 0); |
| 534 | out_8(&iic->lmadr, addr << 1); |
| 535 | } |
| 536 | } |
| 537 | |
| 538 | static inline int iic_invalid_address(const struct i2c_msg* p) |
| 539 | { |
| 540 | return (p->addr > 0x3ff) || (!(p->flags & I2C_M_TEN) && (p->addr > 0x7f)); |
| 541 | } |
| 542 | |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 543 | static inline int iic_address_neq(const struct i2c_msg* p1, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 544 | const struct i2c_msg* p2) |
| 545 | { |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 546 | return (p1->addr != p2->addr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 547 | || ((p1->flags & I2C_M_TEN) != (p2->flags & I2C_M_TEN)); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 548 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 549 | |
| 550 | /* |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 551 | * Generic master transfer entrypoint. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 552 | * Returns the number of processed messages or error (<0) |
| 553 | */ |
| 554 | static int iic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) |
| 555 | { |
| 556 | struct ibm_iic_private* dev = (struct ibm_iic_private*)(i2c_get_adapdata(adap)); |
| 557 | volatile struct iic_regs __iomem *iic = dev->vaddr; |
| 558 | int i, ret = 0; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 559 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 560 | DBG2("%d: iic_xfer, %d msg(s)\n", dev->idx, num); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 561 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 562 | if (!num) |
| 563 | return 0; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 564 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 565 | /* Check the sanity of the passed messages. |
| 566 | * Uhh, generic i2c layer is more suitable place for such code... |
| 567 | */ |
| 568 | if (unlikely(iic_invalid_address(&msgs[0]))){ |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 569 | DBG("%d: invalid address 0x%03x (%d-bit)\n", dev->idx, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 570 | msgs[0].addr, msgs[0].flags & I2C_M_TEN ? 10 : 7); |
| 571 | return -EINVAL; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 572 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 573 | for (i = 0; i < num; ++i){ |
| 574 | if (unlikely(msgs[i].len <= 0)){ |
| 575 | if (num == 1 && !msgs[0].len){ |
| 576 | /* Special case for I2C_SMBUS_QUICK emulation. |
| 577 | * IBM IIC doesn't support 0-length transactions |
| 578 | * so we have to emulate them using bit-banging. |
| 579 | */ |
| 580 | return iic_smbus_quick(dev, &msgs[0]); |
| 581 | } |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 582 | DBG("%d: invalid len %d in msg[%d]\n", dev->idx, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 583 | msgs[i].len, i); |
| 584 | return -EINVAL; |
| 585 | } |
| 586 | if (unlikely(iic_address_neq(&msgs[0], &msgs[i]))){ |
| 587 | DBG("%d: invalid addr in msg[%d]\n", dev->idx, i); |
| 588 | return -EINVAL; |
| 589 | } |
| 590 | } |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 591 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 592 | /* Check bus state */ |
| 593 | if (unlikely((in_8(&iic->extsts) & EXTSTS_BCS_MASK) != EXTSTS_BCS_FREE)){ |
| 594 | DBG("%d: iic_xfer, bus is not free\n", dev->idx); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 595 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 596 | /* Usually it means something serious has happend. |
| 597 | * We *cannot* have unfinished previous transfer |
| 598 | * so it doesn't make any sense to try to stop it. |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 599 | * Probably we were not able to recover from the |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 600 | * previous error. |
| 601 | * The only *reasonable* thing I can think of here |
| 602 | * is soft reset. --ebs |
| 603 | */ |
| 604 | iic_dev_reset(dev); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 605 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 606 | if ((in_8(&iic->extsts) & EXTSTS_BCS_MASK) != EXTSTS_BCS_FREE){ |
| 607 | DBG("%d: iic_xfer, bus is still not free\n", dev->idx); |
| 608 | return -EREMOTEIO; |
| 609 | } |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 610 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 611 | else { |
| 612 | /* Flush master data buffer (just in case) */ |
| 613 | out_8(&iic->mdcntl, in_8(&iic->mdcntl) | MDCNTL_FMDB); |
| 614 | } |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 615 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 616 | /* Load slave address */ |
| 617 | iic_address(dev, &msgs[0]); |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 618 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 619 | /* Do real transfer */ |
| 620 | for (i = 0; i < num && !ret; ++i) |
| 621 | ret = iic_xfer_bytes(dev, &msgs[i], i < num - 1); |
| 622 | |
| 623 | return ret < 0 ? ret : num; |
| 624 | } |
| 625 | |
| 626 | static u32 iic_func(struct i2c_adapter *adap) |
| 627 | { |
| 628 | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR; |
| 629 | } |
| 630 | |
Jean Delvare | 8f9082c | 2006-09-03 22:39:46 +0200 | [diff] [blame] | 631 | static const struct i2c_algorithm iic_algo = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 632 | .master_xfer = iic_xfer, |
| 633 | .functionality = iic_func |
| 634 | }; |
| 635 | |
| 636 | /* |
| 637 | * Calculates IICx_CLCKDIV value for a specific OPB clock frequency |
| 638 | */ |
| 639 | static inline u8 iic_clckdiv(unsigned int opb) |
| 640 | { |
| 641 | /* Compatibility kludge, should go away after all cards |
| 642 | * are fixed to fill correct value for opbfreq. |
| 643 | * Previous driver version used hardcoded divider value 4, |
| 644 | * it corresponds to OPB frequency from the range (40, 50] MHz |
| 645 | */ |
| 646 | if (!opb){ |
| 647 | printk(KERN_WARNING "ibm-iic: using compatibility value for OPB freq," |
| 648 | " fix your board specific setup\n"); |
| 649 | opb = 50000000; |
| 650 | } |
| 651 | |
| 652 | /* Convert to MHz */ |
| 653 | opb /= 1000000; |
Stefan Roese | 217bcec | 2008-01-27 18:14:45 +0100 | [diff] [blame] | 654 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | if (opb < 20 || opb > 150){ |
Sean MacLennan | 681aae8 | 2008-04-22 22:16:46 +0200 | [diff] [blame] | 656 | printk(KERN_WARNING "ibm-iic: invalid OPB clock frequency %u MHz\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 657 | opb); |
| 658 | opb = opb < 20 ? 20 : 150; |
| 659 | } |
| 660 | return (u8)((opb + 9) / 10 - 1); |
| 661 | } |
| 662 | |
Sean MacLennan | 838349b | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 663 | static int __devinit iic_request_irq(struct of_device *ofdev, |
| 664 | struct ibm_iic_private *dev) |
| 665 | { |
| 666 | struct device_node *np = ofdev->node; |
| 667 | int irq; |
| 668 | |
| 669 | if (iic_force_poll) |
| 670 | return NO_IRQ; |
| 671 | |
| 672 | irq = irq_of_parse_and_map(np, 0); |
| 673 | if (irq == NO_IRQ) { |
| 674 | dev_err(&ofdev->dev, "irq_of_parse_and_map failed\n"); |
| 675 | return NO_IRQ; |
| 676 | } |
| 677 | |
| 678 | /* Disable interrupts until we finish initialization, assumes |
| 679 | * level-sensitive IRQ setup... |
| 680 | */ |
| 681 | iic_interrupt_mode(dev, 0); |
| 682 | if (request_irq(irq, iic_handler, 0, "IBM IIC", dev)) { |
| 683 | dev_err(&ofdev->dev, "request_irq %d failed\n", irq); |
| 684 | /* Fallback to the polling mode */ |
| 685 | return NO_IRQ; |
| 686 | } |
| 687 | |
| 688 | return irq; |
| 689 | } |
| 690 | |
| 691 | /* |
| 692 | * Register single IIC interface |
| 693 | */ |
| 694 | static int __devinit iic_probe(struct of_device *ofdev, |
| 695 | const struct of_device_id *match) |
| 696 | { |
| 697 | struct device_node *np = ofdev->node; |
| 698 | struct ibm_iic_private *dev; |
| 699 | struct i2c_adapter *adap; |
Sean MacLennan | b1204e6 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 700 | const u32 *freq; |
Sean MacLennan | 838349b | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 701 | int ret; |
| 702 | |
| 703 | dev = kzalloc(sizeof(*dev), GFP_KERNEL); |
| 704 | if (!dev) { |
| 705 | dev_err(&ofdev->dev, "failed to allocate device data\n"); |
| 706 | return -ENOMEM; |
| 707 | } |
| 708 | |
| 709 | dev_set_drvdata(&ofdev->dev, dev); |
| 710 | |
Sean MacLennan | 838349b | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 711 | dev->vaddr = of_iomap(np, 0); |
| 712 | if (dev->vaddr == NULL) { |
| 713 | dev_err(&ofdev->dev, "failed to iomap device\n"); |
| 714 | ret = -ENXIO; |
| 715 | goto error_cleanup; |
| 716 | } |
| 717 | |
| 718 | init_waitqueue_head(&dev->wq); |
| 719 | |
| 720 | dev->irq = iic_request_irq(ofdev, dev); |
| 721 | if (dev->irq == NO_IRQ) |
| 722 | dev_warn(&ofdev->dev, "using polling mode\n"); |
| 723 | |
| 724 | /* Board specific settings */ |
| 725 | if (iic_force_fast || of_get_property(np, "fast-mode", NULL)) |
| 726 | dev->fast_mode = 1; |
| 727 | |
| 728 | freq = of_get_property(np, "clock-frequency", NULL); |
| 729 | if (freq == NULL) { |
| 730 | freq = of_get_property(np->parent, "clock-frequency", NULL); |
| 731 | if (freq == NULL) { |
| 732 | dev_err(&ofdev->dev, "Unable to get bus frequency\n"); |
| 733 | ret = -EINVAL; |
| 734 | goto error_cleanup; |
| 735 | } |
| 736 | } |
| 737 | |
| 738 | dev->clckdiv = iic_clckdiv(*freq); |
| 739 | dev_dbg(&ofdev->dev, "clckdiv = %d\n", dev->clckdiv); |
| 740 | |
| 741 | /* Initialize IIC interface */ |
| 742 | iic_dev_init(dev); |
| 743 | |
| 744 | /* Register it with i2c layer */ |
| 745 | adap = &dev->adap; |
| 746 | adap->dev.parent = &ofdev->dev; |
| 747 | strlcpy(adap->name, "IBM IIC", sizeof(adap->name)); |
| 748 | i2c_set_adapdata(adap, dev); |
Jean Delvare | 3401b2f | 2008-07-14 22:38:29 +0200 | [diff] [blame] | 749 | adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD; |
Sean MacLennan | 838349b | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 750 | adap->algo = &iic_algo; |
Jean Delvare | 8a52c6b | 2009-03-28 21:34:43 +0100 | [diff] [blame^] | 751 | adap->timeout = HZ; |
Sean MacLennan | 838349b | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 752 | |
Sean MacLennan | b1204e6 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 753 | ret = i2c_add_adapter(adap); |
Sean MacLennan | 838349b | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 754 | if (ret < 0) { |
| 755 | dev_err(&ofdev->dev, "failed to register i2c adapter\n"); |
| 756 | goto error_cleanup; |
| 757 | } |
| 758 | |
Sean MacLennan | b1204e6 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 759 | /* Now register all the child nodes */ |
| 760 | of_register_i2c_devices(adap, np); |
| 761 | |
Sean MacLennan | 838349b | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 762 | dev_info(&ofdev->dev, "using %s mode\n", |
| 763 | dev->fast_mode ? "fast (400 kHz)" : "standard (100 kHz)"); |
| 764 | |
| 765 | return 0; |
| 766 | |
| 767 | error_cleanup: |
| 768 | if (dev->irq != NO_IRQ) { |
| 769 | iic_interrupt_mode(dev, 0); |
| 770 | free_irq(dev->irq, dev); |
| 771 | } |
| 772 | |
| 773 | if (dev->vaddr) |
| 774 | iounmap(dev->vaddr); |
| 775 | |
| 776 | dev_set_drvdata(&ofdev->dev, NULL); |
| 777 | kfree(dev); |
| 778 | return ret; |
| 779 | } |
| 780 | |
| 781 | /* |
| 782 | * Cleanup initialized IIC interface |
| 783 | */ |
| 784 | static int __devexit iic_remove(struct of_device *ofdev) |
| 785 | { |
| 786 | struct ibm_iic_private *dev = dev_get_drvdata(&ofdev->dev); |
| 787 | |
| 788 | dev_set_drvdata(&ofdev->dev, NULL); |
| 789 | |
| 790 | i2c_del_adapter(&dev->adap); |
| 791 | |
| 792 | if (dev->irq != NO_IRQ) { |
| 793 | iic_interrupt_mode(dev, 0); |
| 794 | free_irq(dev->irq, dev); |
| 795 | } |
| 796 | |
| 797 | iounmap(dev->vaddr); |
| 798 | kfree(dev); |
| 799 | |
| 800 | return 0; |
| 801 | } |
| 802 | |
| 803 | static const struct of_device_id ibm_iic_match[] = { |
Stefan Roese | d3dc685 | 2008-07-14 22:38:30 +0200 | [diff] [blame] | 804 | { .compatible = "ibm,iic", }, |
Sean MacLennan | 838349b | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 805 | {} |
| 806 | }; |
| 807 | |
| 808 | static struct of_platform_driver ibm_iic_driver = { |
| 809 | .name = "ibm-iic", |
| 810 | .match_table = ibm_iic_match, |
| 811 | .probe = iic_probe, |
| 812 | .remove = __devexit_p(iic_remove), |
| 813 | }; |
| 814 | |
| 815 | static int __init iic_init(void) |
| 816 | { |
| 817 | return of_register_platform_driver(&ibm_iic_driver); |
| 818 | } |
| 819 | |
| 820 | static void __exit iic_exit(void) |
| 821 | { |
| 822 | of_unregister_platform_driver(&ibm_iic_driver); |
| 823 | } |
Sean MacLennan | 838349b | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 824 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 825 | module_init(iic_init); |
| 826 | module_exit(iic_exit); |