Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Provides I2C support for Philips PNX010x/PNX4008 boards. |
| 3 | * |
| 4 | * Authors: Dennis Kovalev <dkovalev@ru.mvista.com> |
| 5 | * Vitaly Wool <vwool@ru.mvista.com> |
| 6 | * |
| 7 | * 2004-2006 (c) MontaVista Software, Inc. This file is licensed under |
| 8 | * the terms of the GNU General Public License version 2. This program |
| 9 | * is licensed "as is" without any warranty of any kind, whether express |
| 10 | * or implied. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/interrupt.h> |
| 15 | #include <linux/ioport.h> |
| 16 | #include <linux/delay.h> |
| 17 | #include <linux/i2c.h> |
| 18 | #include <linux/timer.h> |
| 19 | #include <linux/completion.h> |
| 20 | #include <linux/platform_device.h> |
| 21 | #include <linux/i2c-pnx.h> |
Kevin Wells | a7d73d8 | 2009-11-12 00:25:52 +0100 | [diff] [blame^] | 22 | #include <linux/io.h> |
Russell King | a09e64f | 2008-08-05 16:14:15 +0100 | [diff] [blame] | 23 | #include <mach/hardware.h> |
Kevin Wells | a7d73d8 | 2009-11-12 00:25:52 +0100 | [diff] [blame^] | 24 | #include <mach/i2c.h> |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 25 | #include <asm/irq.h> |
| 26 | #include <asm/uaccess.h> |
| 27 | |
| 28 | #define I2C_PNX_TIMEOUT 10 /* msec */ |
| 29 | #define I2C_PNX_SPEED_KHZ 100 |
| 30 | #define I2C_PNX_REGION_SIZE 0x100 |
| 31 | #define PNX_DEFAULT_FREQ 13 /* MHz */ |
| 32 | |
| 33 | static inline int wait_timeout(long timeout, struct i2c_pnx_algo_data *data) |
| 34 | { |
| 35 | while (timeout > 0 && |
| 36 | (ioread32(I2C_REG_STS(data)) & mstatus_active)) { |
| 37 | mdelay(1); |
| 38 | timeout--; |
| 39 | } |
| 40 | return (timeout <= 0); |
| 41 | } |
| 42 | |
| 43 | static inline int wait_reset(long timeout, struct i2c_pnx_algo_data *data) |
| 44 | { |
| 45 | while (timeout > 0 && |
| 46 | (ioread32(I2C_REG_CTL(data)) & mcntrl_reset)) { |
| 47 | mdelay(1); |
| 48 | timeout--; |
| 49 | } |
| 50 | return (timeout <= 0); |
| 51 | } |
| 52 | |
| 53 | static inline void i2c_pnx_arm_timer(struct i2c_adapter *adap) |
| 54 | { |
| 55 | struct i2c_pnx_algo_data *data = adap->algo_data; |
| 56 | struct timer_list *timer = &data->mif.timer; |
| 57 | int expires = I2C_PNX_TIMEOUT / (1000 / HZ); |
| 58 | |
Kevin Wells | b2f125b | 2009-11-12 00:28:13 +0100 | [diff] [blame] | 59 | if (expires <= 1) |
| 60 | expires = 2; |
| 61 | |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 62 | del_timer_sync(timer); |
| 63 | |
| 64 | dev_dbg(&adap->dev, "Timer armed at %lu plus %u jiffies.\n", |
| 65 | jiffies, expires); |
| 66 | |
| 67 | timer->expires = jiffies + expires; |
| 68 | timer->data = (unsigned long)adap; |
| 69 | |
| 70 | add_timer(timer); |
| 71 | } |
| 72 | |
| 73 | /** |
| 74 | * i2c_pnx_start - start a device |
| 75 | * @slave_addr: slave address |
| 76 | * @adap: pointer to adapter structure |
| 77 | * |
| 78 | * Generate a START signal in the desired mode. |
| 79 | */ |
| 80 | static int i2c_pnx_start(unsigned char slave_addr, struct i2c_adapter *adap) |
| 81 | { |
| 82 | struct i2c_pnx_algo_data *alg_data = adap->algo_data; |
| 83 | |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 84 | dev_dbg(&adap->dev, "%s(): addr 0x%x mode %d\n", __func__, |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 85 | slave_addr, alg_data->mif.mode); |
| 86 | |
| 87 | /* Check for 7 bit slave addresses only */ |
| 88 | if (slave_addr & ~0x7f) { |
| 89 | dev_err(&adap->dev, "%s: Invalid slave address %x. " |
| 90 | "Only 7-bit addresses are supported\n", |
| 91 | adap->name, slave_addr); |
| 92 | return -EINVAL; |
| 93 | } |
| 94 | |
| 95 | /* First, make sure bus is idle */ |
| 96 | if (wait_timeout(I2C_PNX_TIMEOUT, alg_data)) { |
| 97 | /* Somebody else is monopolizing the bus */ |
| 98 | dev_err(&adap->dev, "%s: Bus busy. Slave addr = %02x, " |
| 99 | "cntrl = %x, stat = %x\n", |
| 100 | adap->name, slave_addr, |
| 101 | ioread32(I2C_REG_CTL(alg_data)), |
| 102 | ioread32(I2C_REG_STS(alg_data))); |
| 103 | return -EBUSY; |
| 104 | } else if (ioread32(I2C_REG_STS(alg_data)) & mstatus_afi) { |
| 105 | /* Sorry, we lost the bus */ |
| 106 | dev_err(&adap->dev, "%s: Arbitration failure. " |
| 107 | "Slave addr = %02x\n", adap->name, slave_addr); |
| 108 | return -EIO; |
| 109 | } |
| 110 | |
| 111 | /* |
| 112 | * OK, I2C is enabled and we have the bus. |
| 113 | * Clear the current TDI and AFI status flags. |
| 114 | */ |
| 115 | iowrite32(ioread32(I2C_REG_STS(alg_data)) | mstatus_tdi | mstatus_afi, |
| 116 | I2C_REG_STS(alg_data)); |
| 117 | |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 118 | dev_dbg(&adap->dev, "%s(): sending %#x\n", __func__, |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 119 | (slave_addr << 1) | start_bit | alg_data->mif.mode); |
| 120 | |
| 121 | /* Write the slave address, START bit and R/W bit */ |
| 122 | iowrite32((slave_addr << 1) | start_bit | alg_data->mif.mode, |
| 123 | I2C_REG_TX(alg_data)); |
| 124 | |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 125 | dev_dbg(&adap->dev, "%s(): exit\n", __func__); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 126 | |
| 127 | return 0; |
| 128 | } |
| 129 | |
| 130 | /** |
| 131 | * i2c_pnx_stop - stop a device |
| 132 | * @adap: pointer to I2C adapter structure |
| 133 | * |
| 134 | * Generate a STOP signal to terminate the master transaction. |
| 135 | */ |
| 136 | static void i2c_pnx_stop(struct i2c_adapter *adap) |
| 137 | { |
| 138 | struct i2c_pnx_algo_data *alg_data = adap->algo_data; |
| 139 | /* Only 1 msec max timeout due to interrupt context */ |
| 140 | long timeout = 1000; |
| 141 | |
| 142 | dev_dbg(&adap->dev, "%s(): entering: stat = %04x.\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 143 | __func__, ioread32(I2C_REG_STS(alg_data))); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 144 | |
| 145 | /* Write a STOP bit to TX FIFO */ |
| 146 | iowrite32(0xff | stop_bit, I2C_REG_TX(alg_data)); |
| 147 | |
| 148 | /* Wait until the STOP is seen. */ |
| 149 | while (timeout > 0 && |
| 150 | (ioread32(I2C_REG_STS(alg_data)) & mstatus_active)) { |
| 151 | /* may be called from interrupt context */ |
| 152 | udelay(1); |
| 153 | timeout--; |
| 154 | } |
| 155 | |
| 156 | dev_dbg(&adap->dev, "%s(): exiting: stat = %04x.\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 157 | __func__, ioread32(I2C_REG_STS(alg_data))); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 158 | } |
| 159 | |
| 160 | /** |
| 161 | * i2c_pnx_master_xmit - transmit data to slave |
| 162 | * @adap: pointer to I2C adapter structure |
| 163 | * |
| 164 | * Sends one byte of data to the slave |
| 165 | */ |
| 166 | static int i2c_pnx_master_xmit(struct i2c_adapter *adap) |
| 167 | { |
| 168 | struct i2c_pnx_algo_data *alg_data = adap->algo_data; |
| 169 | u32 val; |
| 170 | |
| 171 | dev_dbg(&adap->dev, "%s(): entering: stat = %04x.\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 172 | __func__, ioread32(I2C_REG_STS(alg_data))); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 173 | |
| 174 | if (alg_data->mif.len > 0) { |
| 175 | /* We still have something to talk about... */ |
| 176 | val = *alg_data->mif.buf++; |
| 177 | |
| 178 | if (alg_data->mif.len == 1) { |
| 179 | val |= stop_bit; |
| 180 | if (!alg_data->last) |
| 181 | val |= start_bit; |
| 182 | } |
| 183 | |
| 184 | alg_data->mif.len--; |
| 185 | iowrite32(val, I2C_REG_TX(alg_data)); |
| 186 | |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 187 | dev_dbg(&adap->dev, "%s(): xmit %#x [%d]\n", __func__, |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 188 | val, alg_data->mif.len + 1); |
| 189 | |
| 190 | if (alg_data->mif.len == 0) { |
| 191 | if (alg_data->last) { |
| 192 | /* Wait until the STOP is seen. */ |
| 193 | if (wait_timeout(I2C_PNX_TIMEOUT, alg_data)) |
| 194 | dev_err(&adap->dev, "The bus is still " |
| 195 | "active after timeout\n"); |
| 196 | } |
| 197 | /* Disable master interrupts */ |
| 198 | iowrite32(ioread32(I2C_REG_CTL(alg_data)) & |
| 199 | ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie), |
| 200 | I2C_REG_CTL(alg_data)); |
| 201 | |
| 202 | del_timer_sync(&alg_data->mif.timer); |
| 203 | |
| 204 | dev_dbg(&adap->dev, "%s(): Waking up xfer routine.\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 205 | __func__); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 206 | |
| 207 | complete(&alg_data->mif.complete); |
| 208 | } |
| 209 | } else if (alg_data->mif.len == 0) { |
| 210 | /* zero-sized transfer */ |
| 211 | i2c_pnx_stop(adap); |
| 212 | |
| 213 | /* Disable master interrupts. */ |
| 214 | iowrite32(ioread32(I2C_REG_CTL(alg_data)) & |
| 215 | ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie), |
| 216 | I2C_REG_CTL(alg_data)); |
| 217 | |
| 218 | /* Stop timer. */ |
| 219 | del_timer_sync(&alg_data->mif.timer); |
| 220 | dev_dbg(&adap->dev, "%s(): Waking up xfer routine after " |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 221 | "zero-xfer.\n", __func__); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 222 | |
| 223 | complete(&alg_data->mif.complete); |
| 224 | } |
| 225 | |
| 226 | dev_dbg(&adap->dev, "%s(): exiting: stat = %04x.\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 227 | __func__, ioread32(I2C_REG_STS(alg_data))); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 228 | |
| 229 | return 0; |
| 230 | } |
| 231 | |
| 232 | /** |
| 233 | * i2c_pnx_master_rcv - receive data from slave |
| 234 | * @adap: pointer to I2C adapter structure |
| 235 | * |
| 236 | * Reads one byte data from the slave |
| 237 | */ |
| 238 | static int i2c_pnx_master_rcv(struct i2c_adapter *adap) |
| 239 | { |
| 240 | struct i2c_pnx_algo_data *alg_data = adap->algo_data; |
| 241 | unsigned int val = 0; |
| 242 | u32 ctl = 0; |
| 243 | |
| 244 | dev_dbg(&adap->dev, "%s(): entering: stat = %04x.\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 245 | __func__, ioread32(I2C_REG_STS(alg_data))); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 246 | |
| 247 | /* Check, whether there is already data, |
| 248 | * or we didn't 'ask' for it yet. |
| 249 | */ |
| 250 | if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) { |
| 251 | dev_dbg(&adap->dev, "%s(): Write dummy data to fill " |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 252 | "Rx-fifo...\n", __func__); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 253 | |
| 254 | if (alg_data->mif.len == 1) { |
| 255 | /* Last byte, do not acknowledge next rcv. */ |
| 256 | val |= stop_bit; |
| 257 | if (!alg_data->last) |
| 258 | val |= start_bit; |
| 259 | |
| 260 | /* |
| 261 | * Enable interrupt RFDAIE (data in Rx fifo), |
| 262 | * and disable DRMIE (need data for Tx) |
| 263 | */ |
| 264 | ctl = ioread32(I2C_REG_CTL(alg_data)); |
| 265 | ctl |= mcntrl_rffie | mcntrl_daie; |
| 266 | ctl &= ~mcntrl_drmie; |
| 267 | iowrite32(ctl, I2C_REG_CTL(alg_data)); |
| 268 | } |
| 269 | |
| 270 | /* |
| 271 | * Now we'll 'ask' for data: |
| 272 | * For each byte we want to receive, we must |
| 273 | * write a (dummy) byte to the Tx-FIFO. |
| 274 | */ |
| 275 | iowrite32(val, I2C_REG_TX(alg_data)); |
| 276 | |
| 277 | return 0; |
| 278 | } |
| 279 | |
| 280 | /* Handle data. */ |
| 281 | if (alg_data->mif.len > 0) { |
| 282 | val = ioread32(I2C_REG_RX(alg_data)); |
| 283 | *alg_data->mif.buf++ = (u8) (val & 0xff); |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 284 | dev_dbg(&adap->dev, "%s(): rcv 0x%x [%d]\n", __func__, val, |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 285 | alg_data->mif.len); |
| 286 | |
| 287 | alg_data->mif.len--; |
| 288 | if (alg_data->mif.len == 0) { |
| 289 | if (alg_data->last) |
| 290 | /* Wait until the STOP is seen. */ |
| 291 | if (wait_timeout(I2C_PNX_TIMEOUT, alg_data)) |
| 292 | dev_err(&adap->dev, "The bus is still " |
| 293 | "active after timeout\n"); |
| 294 | |
| 295 | /* Disable master interrupts */ |
| 296 | ctl = ioread32(I2C_REG_CTL(alg_data)); |
| 297 | ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | |
| 298 | mcntrl_drmie | mcntrl_daie); |
| 299 | iowrite32(ctl, I2C_REG_CTL(alg_data)); |
| 300 | |
| 301 | /* Kill timer. */ |
| 302 | del_timer_sync(&alg_data->mif.timer); |
| 303 | complete(&alg_data->mif.complete); |
| 304 | } |
| 305 | } |
| 306 | |
| 307 | dev_dbg(&adap->dev, "%s(): exiting: stat = %04x.\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 308 | __func__, ioread32(I2C_REG_STS(alg_data))); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 309 | |
| 310 | return 0; |
| 311 | } |
| 312 | |
Vitaly Wool | 6c566fb7 | 2007-01-04 13:07:03 +0100 | [diff] [blame] | 313 | static irqreturn_t i2c_pnx_interrupt(int irq, void *dev_id) |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 314 | { |
| 315 | u32 stat, ctl; |
| 316 | struct i2c_adapter *adap = dev_id; |
| 317 | struct i2c_pnx_algo_data *alg_data = adap->algo_data; |
| 318 | |
| 319 | dev_dbg(&adap->dev, "%s(): mstat = %x mctrl = %x, mode = %d\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 320 | __func__, |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 321 | ioread32(I2C_REG_STS(alg_data)), |
| 322 | ioread32(I2C_REG_CTL(alg_data)), |
| 323 | alg_data->mif.mode); |
| 324 | stat = ioread32(I2C_REG_STS(alg_data)); |
| 325 | |
| 326 | /* let's see what kind of event this is */ |
| 327 | if (stat & mstatus_afi) { |
| 328 | /* We lost arbitration in the midst of a transfer */ |
| 329 | alg_data->mif.ret = -EIO; |
| 330 | |
| 331 | /* Disable master interrupts. */ |
| 332 | ctl = ioread32(I2C_REG_CTL(alg_data)); |
| 333 | ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | |
| 334 | mcntrl_drmie); |
| 335 | iowrite32(ctl, I2C_REG_CTL(alg_data)); |
| 336 | |
| 337 | /* Stop timer, to prevent timeout. */ |
| 338 | del_timer_sync(&alg_data->mif.timer); |
| 339 | complete(&alg_data->mif.complete); |
| 340 | } else if (stat & mstatus_nai) { |
| 341 | /* Slave did not acknowledge, generate a STOP */ |
| 342 | dev_dbg(&adap->dev, "%s(): " |
| 343 | "Slave did not acknowledge, generating a STOP.\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 344 | __func__); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 345 | i2c_pnx_stop(adap); |
| 346 | |
| 347 | /* Disable master interrupts. */ |
| 348 | ctl = ioread32(I2C_REG_CTL(alg_data)); |
| 349 | ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | |
| 350 | mcntrl_drmie); |
| 351 | iowrite32(ctl, I2C_REG_CTL(alg_data)); |
| 352 | |
| 353 | /* Our return value. */ |
| 354 | alg_data->mif.ret = -EIO; |
| 355 | |
| 356 | /* Stop timer, to prevent timeout. */ |
| 357 | del_timer_sync(&alg_data->mif.timer); |
| 358 | complete(&alg_data->mif.complete); |
| 359 | } else { |
| 360 | /* |
| 361 | * Two options: |
| 362 | * - Master Tx needs data. |
| 363 | * - There is data in the Rx-fifo |
| 364 | * The latter is only the case if we have requested for data, |
| 365 | * via a dummy write. (See 'i2c_pnx_master_rcv'.) |
| 366 | * We therefore check, as a sanity check, whether that interrupt |
| 367 | * has been enabled. |
| 368 | */ |
| 369 | if ((stat & mstatus_drmi) || !(stat & mstatus_rfe)) { |
| 370 | if (alg_data->mif.mode == I2C_SMBUS_WRITE) { |
| 371 | i2c_pnx_master_xmit(adap); |
| 372 | } else if (alg_data->mif.mode == I2C_SMBUS_READ) { |
| 373 | i2c_pnx_master_rcv(adap); |
| 374 | } |
| 375 | } |
| 376 | } |
| 377 | |
| 378 | /* Clear TDI and AFI bits */ |
| 379 | stat = ioread32(I2C_REG_STS(alg_data)); |
| 380 | iowrite32(stat | mstatus_tdi | mstatus_afi, I2C_REG_STS(alg_data)); |
| 381 | |
| 382 | dev_dbg(&adap->dev, "%s(): exiting, stat = %x ctrl = %x.\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 383 | __func__, ioread32(I2C_REG_STS(alg_data)), |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 384 | ioread32(I2C_REG_CTL(alg_data))); |
| 385 | |
| 386 | return IRQ_HANDLED; |
| 387 | } |
| 388 | |
| 389 | static void i2c_pnx_timeout(unsigned long data) |
| 390 | { |
| 391 | struct i2c_adapter *adap = (struct i2c_adapter *)data; |
| 392 | struct i2c_pnx_algo_data *alg_data = adap->algo_data; |
| 393 | u32 ctl; |
| 394 | |
| 395 | dev_err(&adap->dev, "Master timed out. stat = %04x, cntrl = %04x. " |
| 396 | "Resetting master...\n", |
| 397 | ioread32(I2C_REG_STS(alg_data)), |
| 398 | ioread32(I2C_REG_CTL(alg_data))); |
| 399 | |
| 400 | /* Reset master and disable interrupts */ |
| 401 | ctl = ioread32(I2C_REG_CTL(alg_data)); |
| 402 | ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | mcntrl_drmie); |
| 403 | iowrite32(ctl, I2C_REG_CTL(alg_data)); |
| 404 | |
| 405 | ctl |= mcntrl_reset; |
| 406 | iowrite32(ctl, I2C_REG_CTL(alg_data)); |
| 407 | wait_reset(I2C_PNX_TIMEOUT, alg_data); |
| 408 | alg_data->mif.ret = -EIO; |
| 409 | complete(&alg_data->mif.complete); |
| 410 | } |
| 411 | |
| 412 | static inline void bus_reset_if_active(struct i2c_adapter *adap) |
| 413 | { |
| 414 | struct i2c_pnx_algo_data *alg_data = adap->algo_data; |
| 415 | u32 stat; |
| 416 | |
| 417 | if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_active) { |
| 418 | dev_err(&adap->dev, |
| 419 | "%s: Bus is still active after xfer. Reset it...\n", |
| 420 | adap->name); |
| 421 | iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, |
| 422 | I2C_REG_CTL(alg_data)); |
| 423 | wait_reset(I2C_PNX_TIMEOUT, alg_data); |
| 424 | } else if (!(stat & mstatus_rfe) || !(stat & mstatus_tfe)) { |
| 425 | /* If there is data in the fifo's after transfer, |
| 426 | * flush fifo's by reset. |
| 427 | */ |
| 428 | iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, |
| 429 | I2C_REG_CTL(alg_data)); |
| 430 | wait_reset(I2C_PNX_TIMEOUT, alg_data); |
| 431 | } else if (stat & mstatus_nai) { |
| 432 | iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, |
| 433 | I2C_REG_CTL(alg_data)); |
| 434 | wait_reset(I2C_PNX_TIMEOUT, alg_data); |
| 435 | } |
| 436 | } |
| 437 | |
| 438 | /** |
| 439 | * i2c_pnx_xfer - generic transfer entry point |
| 440 | * @adap: pointer to I2C adapter structure |
| 441 | * @msgs: array of messages |
| 442 | * @num: number of messages |
| 443 | * |
| 444 | * Initiates the transfer |
| 445 | */ |
| 446 | static int |
| 447 | i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) |
| 448 | { |
| 449 | struct i2c_msg *pmsg; |
| 450 | int rc = 0, completed = 0, i; |
| 451 | struct i2c_pnx_algo_data *alg_data = adap->algo_data; |
| 452 | u32 stat = ioread32(I2C_REG_STS(alg_data)); |
| 453 | |
| 454 | dev_dbg(&adap->dev, "%s(): entering: %d messages, stat = %04x.\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 455 | __func__, num, ioread32(I2C_REG_STS(alg_data))); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 456 | |
| 457 | bus_reset_if_active(adap); |
| 458 | |
| 459 | /* Process transactions in a loop. */ |
| 460 | for (i = 0; rc >= 0 && i < num; i++) { |
| 461 | u8 addr; |
| 462 | |
| 463 | pmsg = &msgs[i]; |
| 464 | addr = pmsg->addr; |
| 465 | |
| 466 | if (pmsg->flags & I2C_M_TEN) { |
| 467 | dev_err(&adap->dev, |
| 468 | "%s: 10 bits addr not supported!\n", |
| 469 | adap->name); |
| 470 | rc = -EINVAL; |
| 471 | break; |
| 472 | } |
| 473 | |
| 474 | alg_data->mif.buf = pmsg->buf; |
| 475 | alg_data->mif.len = pmsg->len; |
| 476 | alg_data->mif.mode = (pmsg->flags & I2C_M_RD) ? |
| 477 | I2C_SMBUS_READ : I2C_SMBUS_WRITE; |
| 478 | alg_data->mif.ret = 0; |
| 479 | alg_data->last = (i == num - 1); |
| 480 | |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 481 | dev_dbg(&adap->dev, "%s(): mode %d, %d bytes\n", __func__, |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 482 | alg_data->mif.mode, |
| 483 | alg_data->mif.len); |
| 484 | |
| 485 | i2c_pnx_arm_timer(adap); |
| 486 | |
| 487 | /* initialize the completion var */ |
| 488 | init_completion(&alg_data->mif.complete); |
| 489 | |
| 490 | /* Enable master interrupt */ |
| 491 | iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_afie | |
| 492 | mcntrl_naie | mcntrl_drmie, |
| 493 | I2C_REG_CTL(alg_data)); |
| 494 | |
| 495 | /* Put start-code and slave-address on the bus. */ |
| 496 | rc = i2c_pnx_start(addr, adap); |
| 497 | if (rc < 0) |
| 498 | break; |
| 499 | |
| 500 | /* Wait for completion */ |
| 501 | wait_for_completion(&alg_data->mif.complete); |
| 502 | |
| 503 | if (!(rc = alg_data->mif.ret)) |
| 504 | completed++; |
| 505 | dev_dbg(&adap->dev, "%s(): Complete, return code = %d.\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 506 | __func__, rc); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 507 | |
| 508 | /* Clear TDI and AFI bits in case they are set. */ |
| 509 | if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_tdi) { |
| 510 | dev_dbg(&adap->dev, |
| 511 | "%s: TDI still set... clearing now.\n", |
| 512 | adap->name); |
| 513 | iowrite32(stat, I2C_REG_STS(alg_data)); |
| 514 | } |
| 515 | if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_afi) { |
| 516 | dev_dbg(&adap->dev, |
| 517 | "%s: AFI still set... clearing now.\n", |
| 518 | adap->name); |
| 519 | iowrite32(stat, I2C_REG_STS(alg_data)); |
| 520 | } |
| 521 | } |
| 522 | |
| 523 | bus_reset_if_active(adap); |
| 524 | |
| 525 | /* Cleanup to be sure... */ |
| 526 | alg_data->mif.buf = NULL; |
| 527 | alg_data->mif.len = 0; |
| 528 | |
| 529 | dev_dbg(&adap->dev, "%s(): exiting, stat = %x\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 530 | __func__, ioread32(I2C_REG_STS(alg_data))); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 531 | |
| 532 | if (completed != num) |
| 533 | return ((rc < 0) ? rc : -EREMOTEIO); |
| 534 | |
| 535 | return num; |
| 536 | } |
| 537 | |
| 538 | static u32 i2c_pnx_func(struct i2c_adapter *adapter) |
| 539 | { |
| 540 | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; |
| 541 | } |
| 542 | |
| 543 | static struct i2c_algorithm pnx_algorithm = { |
| 544 | .master_xfer = i2c_pnx_xfer, |
| 545 | .functionality = i2c_pnx_func, |
| 546 | }; |
| 547 | |
| 548 | static int i2c_pnx_controller_suspend(struct platform_device *pdev, |
| 549 | pm_message_t state) |
| 550 | { |
| 551 | struct i2c_pnx_data *i2c_pnx = platform_get_drvdata(pdev); |
| 552 | return i2c_pnx->suspend(pdev, state); |
| 553 | } |
| 554 | |
| 555 | static int i2c_pnx_controller_resume(struct platform_device *pdev) |
| 556 | { |
| 557 | struct i2c_pnx_data *i2c_pnx = platform_get_drvdata(pdev); |
| 558 | return i2c_pnx->resume(pdev); |
| 559 | } |
| 560 | |
| 561 | static int __devinit i2c_pnx_probe(struct platform_device *pdev) |
| 562 | { |
| 563 | unsigned long tmp; |
| 564 | int ret = 0; |
| 565 | struct i2c_pnx_algo_data *alg_data; |
| 566 | int freq_mhz; |
| 567 | struct i2c_pnx_data *i2c_pnx = pdev->dev.platform_data; |
| 568 | |
| 569 | if (!i2c_pnx || !i2c_pnx->adapter) { |
| 570 | dev_err(&pdev->dev, "%s: no platform data supplied\n", |
Harvey Harrison | 08882d2 | 2008-04-22 22:16:47 +0200 | [diff] [blame] | 571 | __func__); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 572 | ret = -EINVAL; |
| 573 | goto out; |
| 574 | } |
| 575 | |
| 576 | platform_set_drvdata(pdev, i2c_pnx); |
| 577 | |
| 578 | if (i2c_pnx->calculate_input_freq) |
| 579 | freq_mhz = i2c_pnx->calculate_input_freq(pdev); |
| 580 | else { |
| 581 | freq_mhz = PNX_DEFAULT_FREQ; |
| 582 | dev_info(&pdev->dev, "Setting bus frequency to default value: " |
Joe Perches | 898eb71 | 2007-10-18 03:06:30 -0700 | [diff] [blame] | 583 | "%d MHz\n", freq_mhz); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 584 | } |
| 585 | |
| 586 | i2c_pnx->adapter->algo = &pnx_algorithm; |
| 587 | |
| 588 | alg_data = i2c_pnx->adapter->algo_data; |
| 589 | init_timer(&alg_data->mif.timer); |
| 590 | alg_data->mif.timer.function = i2c_pnx_timeout; |
| 591 | alg_data->mif.timer.data = (unsigned long)i2c_pnx->adapter; |
| 592 | |
| 593 | /* Register I/O resource */ |
Julia Lawall | 449d2c7 | 2009-09-18 22:45:51 +0200 | [diff] [blame] | 594 | if (!request_mem_region(alg_data->base, I2C_PNX_REGION_SIZE, |
| 595 | pdev->name)) { |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 596 | dev_err(&pdev->dev, |
| 597 | "I/O region 0x%08x for I2C already in use.\n", |
| 598 | alg_data->base); |
| 599 | ret = -ENODEV; |
| 600 | goto out_drvdata; |
| 601 | } |
| 602 | |
| 603 | if (!(alg_data->ioaddr = |
| 604 | (u32)ioremap(alg_data->base, I2C_PNX_REGION_SIZE))) { |
| 605 | dev_err(&pdev->dev, "Couldn't ioremap I2C I/O region\n"); |
| 606 | ret = -ENOMEM; |
| 607 | goto out_release; |
| 608 | } |
| 609 | |
| 610 | i2c_pnx->set_clock_run(pdev); |
| 611 | |
| 612 | /* |
| 613 | * Clock Divisor High This value is the number of system clocks |
| 614 | * the serial clock (SCL) will be high. |
| 615 | * For example, if the system clock period is 50 ns and the maximum |
| 616 | * desired serial period is 10000 ns (100 kHz), then CLKHI would be |
| 617 | * set to 0.5*(f_sys/f_i2c)-2=0.5*(20e6/100e3)-2=98. The actual value |
| 618 | * programmed into CLKHI will vary from this slightly due to |
| 619 | * variations in the output pad's rise and fall times as well as |
| 620 | * the deglitching filter length. |
| 621 | */ |
| 622 | |
| 623 | tmp = ((freq_mhz * 1000) / I2C_PNX_SPEED_KHZ) / 2 - 2; |
| 624 | iowrite32(tmp, I2C_REG_CKH(alg_data)); |
| 625 | iowrite32(tmp, I2C_REG_CKL(alg_data)); |
| 626 | |
| 627 | iowrite32(mcntrl_reset, I2C_REG_CTL(alg_data)); |
| 628 | if (wait_reset(I2C_PNX_TIMEOUT, alg_data)) { |
| 629 | ret = -ENODEV; |
| 630 | goto out_unmap; |
| 631 | } |
| 632 | init_completion(&alg_data->mif.complete); |
| 633 | |
| 634 | ret = request_irq(alg_data->irq, i2c_pnx_interrupt, |
| 635 | 0, pdev->name, i2c_pnx->adapter); |
| 636 | if (ret) |
| 637 | goto out_clock; |
| 638 | |
| 639 | /* Register this adapter with the I2C subsystem */ |
| 640 | i2c_pnx->adapter->dev.parent = &pdev->dev; |
| 641 | ret = i2c_add_adapter(i2c_pnx->adapter); |
| 642 | if (ret < 0) { |
| 643 | dev_err(&pdev->dev, "I2C: Failed to add bus\n"); |
| 644 | goto out_irq; |
| 645 | } |
| 646 | |
| 647 | dev_dbg(&pdev->dev, "%s: Master at %#8x, irq %d.\n", |
| 648 | i2c_pnx->adapter->name, alg_data->base, alg_data->irq); |
| 649 | |
| 650 | return 0; |
| 651 | |
| 652 | out_irq: |
| 653 | free_irq(alg_data->irq, alg_data); |
| 654 | out_clock: |
| 655 | i2c_pnx->set_clock_stop(pdev); |
| 656 | out_unmap: |
| 657 | iounmap((void *)alg_data->ioaddr); |
| 658 | out_release: |
Julia Lawall | 449d2c7 | 2009-09-18 22:45:51 +0200 | [diff] [blame] | 659 | release_mem_region(alg_data->base, I2C_PNX_REGION_SIZE); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 660 | out_drvdata: |
| 661 | platform_set_drvdata(pdev, NULL); |
| 662 | out: |
| 663 | return ret; |
| 664 | } |
| 665 | |
| 666 | static int __devexit i2c_pnx_remove(struct platform_device *pdev) |
| 667 | { |
| 668 | struct i2c_pnx_data *i2c_pnx = platform_get_drvdata(pdev); |
| 669 | struct i2c_adapter *adap = i2c_pnx->adapter; |
| 670 | struct i2c_pnx_algo_data *alg_data = adap->algo_data; |
| 671 | |
| 672 | free_irq(alg_data->irq, alg_data); |
| 673 | i2c_del_adapter(adap); |
| 674 | i2c_pnx->set_clock_stop(pdev); |
| 675 | iounmap((void *)alg_data->ioaddr); |
Julia Lawall | 449d2c7 | 2009-09-18 22:45:51 +0200 | [diff] [blame] | 676 | release_mem_region(alg_data->base, I2C_PNX_REGION_SIZE); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 677 | platform_set_drvdata(pdev, NULL); |
| 678 | |
| 679 | return 0; |
| 680 | } |
| 681 | |
| 682 | static struct platform_driver i2c_pnx_driver = { |
| 683 | .driver = { |
| 684 | .name = "pnx-i2c", |
| 685 | .owner = THIS_MODULE, |
| 686 | }, |
| 687 | .probe = i2c_pnx_probe, |
| 688 | .remove = __devexit_p(i2c_pnx_remove), |
| 689 | .suspend = i2c_pnx_controller_suspend, |
| 690 | .resume = i2c_pnx_controller_resume, |
| 691 | }; |
| 692 | |
| 693 | static int __init i2c_adap_pnx_init(void) |
| 694 | { |
| 695 | return platform_driver_register(&i2c_pnx_driver); |
| 696 | } |
| 697 | |
| 698 | static void __exit i2c_adap_pnx_exit(void) |
| 699 | { |
| 700 | platform_driver_unregister(&i2c_pnx_driver); |
| 701 | } |
| 702 | |
| 703 | MODULE_AUTHOR("Vitaly Wool, Dennis Kovalev <source@mvista.com>"); |
| 704 | MODULE_DESCRIPTION("I2C driver for Philips IP3204-based I2C busses"); |
| 705 | MODULE_LICENSE("GPL"); |
Kay Sievers | add8eda | 2008-04-22 22:16:49 +0200 | [diff] [blame] | 706 | MODULE_ALIAS("platform:pnx-i2c"); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 707 | |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 708 | /* We need to make sure I2C is initialized before USB */ |
| 709 | subsys_initcall(i2c_adap_pnx_init); |
Vitaly Wool | 41561f2 | 2006-12-10 21:21:29 +0100 | [diff] [blame] | 710 | module_exit(i2c_adap_pnx_exit); |