Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * (C) Copyright 2003-2004 |
| 3 | * Humboldt Solutions Ltd, adrian@humboldt.co.uk. |
| 4 | |
| 5 | * This is a combined i2c adapter and algorithm driver for the |
| 6 | * MPC107/Tsi107 PowerPC northbridge and processors that include |
| 7 | * the same I2C unit (8240, 8245, 85xx). |
| 8 | * |
| 9 | * Release 0.8 |
| 10 | * |
| 11 | * This file is licensed under the terms of the GNU General Public |
| 12 | * License version 2. This program is licensed "as is" without any |
| 13 | * warranty of any kind, whether express or implied. |
| 14 | */ |
| 15 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | #include <linux/kernel.h> |
| 17 | #include <linux/module.h> |
| 18 | #include <linux/sched.h> |
| 19 | #include <linux/init.h> |
Russell King | d052d1b | 2005-10-29 19:07:23 +0100 | [diff] [blame] | 20 | #include <linux/platform_device.h> |
| 21 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | #include <asm/io.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #include <linux/fsl_devices.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | #include <linux/i2c.h> |
| 25 | #include <linux/interrupt.h> |
| 26 | #include <linux/delay.h> |
| 27 | |
| 28 | #define MPC_I2C_ADDR 0x00 |
| 29 | #define MPC_I2C_FDR 0x04 |
| 30 | #define MPC_I2C_CR 0x08 |
| 31 | #define MPC_I2C_SR 0x0c |
| 32 | #define MPC_I2C_DR 0x10 |
| 33 | #define MPC_I2C_DFSRR 0x14 |
| 34 | #define MPC_I2C_REGION 0x20 |
| 35 | |
| 36 | #define CCR_MEN 0x80 |
| 37 | #define CCR_MIEN 0x40 |
| 38 | #define CCR_MSTA 0x20 |
| 39 | #define CCR_MTX 0x10 |
| 40 | #define CCR_TXAK 0x08 |
| 41 | #define CCR_RSTA 0x04 |
| 42 | |
| 43 | #define CSR_MCF 0x80 |
| 44 | #define CSR_MAAS 0x40 |
| 45 | #define CSR_MBB 0x20 |
| 46 | #define CSR_MAL 0x10 |
| 47 | #define CSR_SRW 0x04 |
| 48 | #define CSR_MIF 0x02 |
| 49 | #define CSR_RXAK 0x01 |
| 50 | |
| 51 | struct mpc_i2c { |
Al Viro | 7366d36 | 2005-04-25 18:32:12 -0700 | [diff] [blame] | 52 | void __iomem *base; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | u32 interrupt; |
| 54 | wait_queue_head_t queue; |
| 55 | struct i2c_adapter adap; |
| 56 | int irq; |
| 57 | u32 flags; |
| 58 | }; |
| 59 | |
| 60 | static __inline__ void writeccr(struct mpc_i2c *i2c, u32 x) |
| 61 | { |
| 62 | writeb(x, i2c->base + MPC_I2C_CR); |
| 63 | } |
| 64 | |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 65 | static irqreturn_t mpc_i2c_isr(int irq, void *dev_id) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | { |
| 67 | struct mpc_i2c *i2c = dev_id; |
| 68 | if (readb(i2c->base + MPC_I2C_SR) & CSR_MIF) { |
| 69 | /* Read again to allow register to stabilise */ |
| 70 | i2c->interrupt = readb(i2c->base + MPC_I2C_SR); |
| 71 | writeb(0, i2c->base + MPC_I2C_SR); |
| 72 | wake_up_interruptible(&i2c->queue); |
| 73 | } |
| 74 | return IRQ_HANDLED; |
| 75 | } |
| 76 | |
Domen Puncer | 254db9b | 2007-07-12 14:12:31 +0200 | [diff] [blame] | 77 | /* Sometimes 9th clock pulse isn't generated, and slave doesn't release |
| 78 | * the bus, because it wants to send ACK. |
| 79 | * Following sequence of enabling/disabling and sending start/stop generates |
| 80 | * the pulse, so it's all OK. |
| 81 | */ |
| 82 | static void mpc_i2c_fixup(struct mpc_i2c *i2c) |
| 83 | { |
| 84 | writeccr(i2c, 0); |
| 85 | udelay(30); |
| 86 | writeccr(i2c, CCR_MEN); |
| 87 | udelay(30); |
| 88 | writeccr(i2c, CCR_MSTA | CCR_MTX); |
| 89 | udelay(30); |
| 90 | writeccr(i2c, CCR_MSTA | CCR_MTX | CCR_MEN); |
| 91 | udelay(30); |
| 92 | writeccr(i2c, CCR_MEN); |
| 93 | udelay(30); |
| 94 | } |
| 95 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing) |
| 97 | { |
| 98 | unsigned long orig_jiffies = jiffies; |
| 99 | u32 x; |
| 100 | int result = 0; |
| 101 | |
| 102 | if (i2c->irq == 0) |
| 103 | { |
| 104 | while (!(readb(i2c->base + MPC_I2C_SR) & CSR_MIF)) { |
| 105 | schedule(); |
| 106 | if (time_after(jiffies, orig_jiffies + timeout)) { |
| 107 | pr_debug("I2C: timeout\n"); |
| 108 | result = -EIO; |
| 109 | break; |
| 110 | } |
| 111 | } |
| 112 | x = readb(i2c->base + MPC_I2C_SR); |
| 113 | writeb(0, i2c->base + MPC_I2C_SR); |
| 114 | } else { |
| 115 | /* Interrupt mode */ |
| 116 | result = wait_event_interruptible_timeout(i2c->queue, |
| 117 | (i2c->interrupt & CSR_MIF), timeout * HZ); |
| 118 | |
| 119 | if (unlikely(result < 0)) |
| 120 | pr_debug("I2C: wait interrupted\n"); |
| 121 | else if (unlikely(!(i2c->interrupt & CSR_MIF))) { |
| 122 | pr_debug("I2C: wait timeout\n"); |
| 123 | result = -ETIMEDOUT; |
| 124 | } |
| 125 | |
| 126 | x = i2c->interrupt; |
| 127 | i2c->interrupt = 0; |
| 128 | } |
| 129 | |
| 130 | if (result < 0) |
| 131 | return result; |
| 132 | |
| 133 | if (!(x & CSR_MCF)) { |
| 134 | pr_debug("I2C: unfinished\n"); |
| 135 | return -EIO; |
| 136 | } |
| 137 | |
| 138 | if (x & CSR_MAL) { |
| 139 | pr_debug("I2C: MAL\n"); |
| 140 | return -EIO; |
| 141 | } |
| 142 | |
| 143 | if (writing && (x & CSR_RXAK)) { |
| 144 | pr_debug("I2C: No RXAK\n"); |
| 145 | /* generate stop */ |
| 146 | writeccr(i2c, CCR_MEN); |
| 147 | return -EIO; |
| 148 | } |
| 149 | return 0; |
| 150 | } |
| 151 | |
| 152 | static void mpc_i2c_setclock(struct mpc_i2c *i2c) |
| 153 | { |
| 154 | /* Set clock and filters */ |
| 155 | if (i2c->flags & FSL_I2C_DEV_SEPARATE_DFSRR) { |
| 156 | writeb(0x31, i2c->base + MPC_I2C_FDR); |
| 157 | writeb(0x10, i2c->base + MPC_I2C_DFSRR); |
| 158 | } else if (i2c->flags & FSL_I2C_DEV_CLOCK_5200) |
| 159 | writeb(0x3f, i2c->base + MPC_I2C_FDR); |
| 160 | else |
| 161 | writel(0x1031, i2c->base + MPC_I2C_FDR); |
| 162 | } |
| 163 | |
| 164 | static void mpc_i2c_start(struct mpc_i2c *i2c) |
| 165 | { |
| 166 | /* Clear arbitration */ |
| 167 | writeb(0, i2c->base + MPC_I2C_SR); |
| 168 | /* Start with MEN */ |
| 169 | writeccr(i2c, CCR_MEN); |
| 170 | } |
| 171 | |
| 172 | static void mpc_i2c_stop(struct mpc_i2c *i2c) |
| 173 | { |
| 174 | writeccr(i2c, CCR_MEN); |
Domen Puncer | 254db9b | 2007-07-12 14:12:31 +0200 | [diff] [blame] | 175 | writeccr(i2c, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 176 | } |
| 177 | |
| 178 | static int mpc_write(struct mpc_i2c *i2c, int target, |
| 179 | const u8 * data, int length, int restart) |
| 180 | { |
| 181 | int i; |
| 182 | unsigned timeout = i2c->adap.timeout; |
| 183 | u32 flags = restart ? CCR_RSTA : 0; |
| 184 | |
| 185 | /* Start with MEN */ |
| 186 | if (!restart) |
| 187 | writeccr(i2c, CCR_MEN); |
| 188 | /* Start as master */ |
| 189 | writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags); |
| 190 | /* Write target byte */ |
| 191 | writeb((target << 1), i2c->base + MPC_I2C_DR); |
| 192 | |
| 193 | if (i2c_wait(i2c, timeout, 1) < 0) |
| 194 | return -1; |
| 195 | |
| 196 | for (i = 0; i < length; i++) { |
| 197 | /* Write data byte */ |
| 198 | writeb(data[i], i2c->base + MPC_I2C_DR); |
| 199 | |
| 200 | if (i2c_wait(i2c, timeout, 1) < 0) |
| 201 | return -1; |
| 202 | } |
| 203 | |
| 204 | return 0; |
| 205 | } |
| 206 | |
| 207 | static int mpc_read(struct mpc_i2c *i2c, int target, |
| 208 | u8 * data, int length, int restart) |
| 209 | { |
| 210 | unsigned timeout = i2c->adap.timeout; |
| 211 | int i; |
| 212 | u32 flags = restart ? CCR_RSTA : 0; |
| 213 | |
| 214 | /* Start with MEN */ |
| 215 | if (!restart) |
| 216 | writeccr(i2c, CCR_MEN); |
| 217 | /* Switch to read - restart */ |
| 218 | writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags); |
| 219 | /* Write target address byte - this time with the read flag set */ |
| 220 | writeb((target << 1) | 1, i2c->base + MPC_I2C_DR); |
| 221 | |
| 222 | if (i2c_wait(i2c, timeout, 1) < 0) |
| 223 | return -1; |
| 224 | |
| 225 | if (length) { |
| 226 | if (length == 1) |
| 227 | writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK); |
| 228 | else |
| 229 | writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA); |
| 230 | /* Dummy read */ |
| 231 | readb(i2c->base + MPC_I2C_DR); |
| 232 | } |
| 233 | |
| 234 | for (i = 0; i < length; i++) { |
| 235 | if (i2c_wait(i2c, timeout, 0) < 0) |
| 236 | return -1; |
| 237 | |
| 238 | /* Generate txack on next to last byte */ |
| 239 | if (i == length - 2) |
| 240 | writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK); |
| 241 | /* Generate stop on last byte */ |
| 242 | if (i == length - 1) |
| 243 | writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_TXAK); |
| 244 | data[i] = readb(i2c->base + MPC_I2C_DR); |
| 245 | } |
| 246 | |
| 247 | return length; |
| 248 | } |
| 249 | |
| 250 | static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) |
| 251 | { |
| 252 | struct i2c_msg *pmsg; |
| 253 | int i; |
| 254 | int ret = 0; |
| 255 | unsigned long orig_jiffies = jiffies; |
| 256 | struct mpc_i2c *i2c = i2c_get_adapdata(adap); |
| 257 | |
| 258 | mpc_i2c_start(i2c); |
| 259 | |
| 260 | /* Allow bus up to 1s to become not busy */ |
| 261 | while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) { |
| 262 | if (signal_pending(current)) { |
| 263 | pr_debug("I2C: Interrupted\n"); |
| 264 | return -EINTR; |
| 265 | } |
| 266 | if (time_after(jiffies, orig_jiffies + HZ)) { |
| 267 | pr_debug("I2C: timeout\n"); |
Domen Puncer | 254db9b | 2007-07-12 14:12:31 +0200 | [diff] [blame] | 268 | if (readb(i2c->base + MPC_I2C_SR) == |
| 269 | (CSR_MCF | CSR_MBB | CSR_RXAK)) |
| 270 | mpc_i2c_fixup(i2c); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | return -EIO; |
| 272 | } |
| 273 | schedule(); |
| 274 | } |
| 275 | |
| 276 | for (i = 0; ret >= 0 && i < num; i++) { |
| 277 | pmsg = &msgs[i]; |
| 278 | pr_debug("Doing %s %d bytes to 0x%02x - %d of %d messages\n", |
| 279 | pmsg->flags & I2C_M_RD ? "read" : "write", |
| 280 | pmsg->len, pmsg->addr, i + 1, num); |
| 281 | if (pmsg->flags & I2C_M_RD) |
| 282 | ret = |
| 283 | mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i); |
| 284 | else |
| 285 | ret = |
| 286 | mpc_write(i2c, pmsg->addr, pmsg->buf, pmsg->len, i); |
| 287 | } |
| 288 | mpc_i2c_stop(i2c); |
| 289 | return (ret < 0) ? ret : num; |
| 290 | } |
| 291 | |
| 292 | static u32 mpc_functionality(struct i2c_adapter *adap) |
| 293 | { |
| 294 | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; |
| 295 | } |
| 296 | |
Jean Delvare | 8f9082c | 2006-09-03 22:39:46 +0200 | [diff] [blame] | 297 | static const struct i2c_algorithm mpc_algo = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | .master_xfer = mpc_xfer, |
| 299 | .functionality = mpc_functionality, |
| 300 | }; |
| 301 | |
| 302 | static struct i2c_adapter mpc_ops = { |
| 303 | .owner = THIS_MODULE, |
| 304 | .name = "MPC adapter", |
Jean Delvare | c7a4653 | 2005-08-11 23:41:56 +0200 | [diff] [blame] | 305 | .id = I2C_HW_MPC107, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 306 | .algo = &mpc_algo, |
| 307 | .class = I2C_CLASS_HWMON, |
| 308 | .timeout = 1, |
| 309 | .retries = 1 |
| 310 | }; |
| 311 | |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 312 | static int fsl_i2c_probe(struct platform_device *pdev) |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 313 | { |
| 314 | int result = 0; |
| 315 | struct mpc_i2c *i2c; |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 316 | struct fsl_i2c_platform_data *pdata; |
| 317 | struct resource *r = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 318 | |
| 319 | pdata = (struct fsl_i2c_platform_data *) pdev->dev.platform_data; |
| 320 | |
Deepak Saxena | 5263ebb | 2005-10-17 23:09:43 +0200 | [diff] [blame] | 321 | if (!(i2c = kzalloc(sizeof(*i2c), GFP_KERNEL))) { |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 322 | return -ENOMEM; |
| 323 | } |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 324 | |
| 325 | i2c->irq = platform_get_irq(pdev, 0); |
David Vrabel | 4894473 | 2006-01-19 17:56:29 +0000 | [diff] [blame] | 326 | if (i2c->irq < 0) { |
| 327 | result = -ENXIO; |
| 328 | goto fail_get_irq; |
| 329 | } |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 330 | i2c->flags = pdata->device_flags; |
| 331 | init_waitqueue_head(&i2c->queue); |
| 332 | |
| 333 | i2c->base = ioremap((phys_addr_t)r->start, MPC_I2C_REGION); |
| 334 | |
| 335 | if (!i2c->base) { |
| 336 | printk(KERN_ERR "i2c-mpc - failed to map controller\n"); |
| 337 | result = -ENOMEM; |
| 338 | goto fail_map; |
| 339 | } |
| 340 | |
| 341 | if (i2c->irq != 0) |
| 342 | if ((result = request_irq(i2c->irq, mpc_i2c_isr, |
Thomas Gleixner | dace145 | 2006-07-01 19:29:38 -0700 | [diff] [blame] | 343 | IRQF_SHARED, "i2c-mpc", i2c)) < 0) { |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 344 | printk(KERN_ERR |
| 345 | "i2c-mpc - failed to attach interrupt\n"); |
| 346 | goto fail_irq; |
| 347 | } |
| 348 | |
| 349 | mpc_i2c_setclock(i2c); |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 350 | platform_set_drvdata(pdev, i2c); |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 351 | |
| 352 | i2c->adap = mpc_ops; |
Grant Likely | 1469fa2 | 2007-07-12 14:12:29 +0200 | [diff] [blame] | 353 | i2c->adap.nr = pdev->id; |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 354 | i2c_set_adapdata(&i2c->adap, i2c); |
| 355 | i2c->adap.dev.parent = &pdev->dev; |
Grant Likely | 1469fa2 | 2007-07-12 14:12:29 +0200 | [diff] [blame] | 356 | if ((result = i2c_add_numbered_adapter(&i2c->adap)) < 0) { |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 357 | printk(KERN_ERR "i2c-mpc - failed to add adapter\n"); |
| 358 | goto fail_add; |
| 359 | } |
| 360 | |
| 361 | return result; |
| 362 | |
| 363 | fail_add: |
| 364 | if (i2c->irq != 0) |
Scott Wood | 322454a | 2007-08-14 18:37:14 +0200 | [diff] [blame^] | 365 | free_irq(i2c->irq, i2c); |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 366 | fail_irq: |
| 367 | iounmap(i2c->base); |
| 368 | fail_map: |
David Vrabel | 4894473 | 2006-01-19 17:56:29 +0000 | [diff] [blame] | 369 | fail_get_irq: |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 370 | kfree(i2c); |
| 371 | return result; |
| 372 | }; |
| 373 | |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 374 | static int fsl_i2c_remove(struct platform_device *pdev) |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 375 | { |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 376 | struct mpc_i2c *i2c = platform_get_drvdata(pdev); |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 377 | |
| 378 | i2c_del_adapter(&i2c->adap); |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 379 | platform_set_drvdata(pdev, NULL); |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 380 | |
| 381 | if (i2c->irq != 0) |
| 382 | free_irq(i2c->irq, i2c); |
| 383 | |
| 384 | iounmap(i2c->base); |
| 385 | kfree(i2c); |
| 386 | return 0; |
| 387 | }; |
| 388 | |
| 389 | /* Structure for a device driver */ |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 390 | static struct platform_driver fsl_i2c_driver = { |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 391 | .probe = fsl_i2c_probe, |
| 392 | .remove = fsl_i2c_remove, |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 393 | .driver = { |
| 394 | .owner = THIS_MODULE, |
| 395 | .name = "fsl-i2c", |
| 396 | }, |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 397 | }; |
| 398 | |
| 399 | static int __init fsl_i2c_init(void) |
| 400 | { |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 401 | return platform_driver_register(&fsl_i2c_driver); |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 402 | } |
| 403 | |
| 404 | static void __exit fsl_i2c_exit(void) |
| 405 | { |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 406 | platform_driver_unregister(&fsl_i2c_driver); |
Kumar Gala | 8c86cb1 | 2005-07-27 11:43:26 -0700 | [diff] [blame] | 407 | } |
| 408 | |
| 409 | module_init(fsl_i2c_init); |
| 410 | module_exit(fsl_i2c_exit); |
| 411 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 412 | MODULE_AUTHOR("Adrian Cox <adrian@humboldt.co.uk>"); |
| 413 | MODULE_DESCRIPTION |
| 414 | ("I2C-Bus adapter for MPC107 bridge and MPC824x/85xx/52xx processors"); |
| 415 | MODULE_LICENSE("GPL"); |