David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1 | /* |
| 2 | * mmc_spi.c - Access SD/MMC cards through SPI master controllers |
| 3 | * |
| 4 | * (C) Copyright 2005, Intec Automation, |
| 5 | * Mike Lavender (mike@steroidmicros) |
| 6 | * (C) Copyright 2006-2007, David Brownell |
| 7 | * (C) Copyright 2007, Axis Communications, |
| 8 | * Hans-Peter Nilsson (hp@axis.com) |
| 9 | * (C) Copyright 2007, ATRON electronic GmbH, |
| 10 | * Jan Nikitenko <jan.nikitenko@gmail.com> |
| 11 | * |
| 12 | * |
| 13 | * This program is free software; you can redistribute it and/or modify |
| 14 | * it under the terms of the GNU General Public License as published by |
| 15 | * the Free Software Foundation; either version 2 of the License, or |
| 16 | * (at your option) any later version. |
| 17 | * |
| 18 | * This program is distributed in the hope that it will be useful, |
| 19 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 20 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 21 | * GNU General Public License for more details. |
| 22 | * |
| 23 | * You should have received a copy of the GNU General Public License |
| 24 | * along with this program; if not, write to the Free Software |
| 25 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 26 | */ |
Wolfgang Muees | 56e303e | 2009-04-07 15:26:30 +0100 | [diff] [blame] | 27 | #include <linux/sched.h> |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 28 | #include <linux/delay.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 29 | #include <linux/slab.h> |
David Brownell | 23fd504 | 2007-10-14 14:50:25 -0700 | [diff] [blame] | 30 | #include <linux/bio.h> |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 31 | #include <linux/dma-mapping.h> |
| 32 | #include <linux/crc7.h> |
| 33 | #include <linux/crc-itu-t.h> |
Al Viro | e5712a6 | 2007-10-17 01:09:07 +0100 | [diff] [blame] | 34 | #include <linux/scatterlist.h> |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 35 | |
| 36 | #include <linux/mmc/host.h> |
| 37 | #include <linux/mmc/mmc.h> /* for R1_SPI_* bit values */ |
| 38 | |
| 39 | #include <linux/spi/spi.h> |
| 40 | #include <linux/spi/mmc_spi.h> |
| 41 | |
| 42 | #include <asm/unaligned.h> |
| 43 | |
| 44 | |
| 45 | /* NOTES: |
| 46 | * |
| 47 | * - For now, we won't try to interoperate with a real mmc/sd/sdio |
| 48 | * controller, although some of them do have hardware support for |
| 49 | * SPI protocol. The main reason for such configs would be mmc-ish |
| 50 | * cards like DataFlash, which don't support that "native" protocol. |
| 51 | * |
| 52 | * We don't have a "DataFlash/MMC/SD/SDIO card slot" abstraction to |
| 53 | * switch between driver stacks, and in any case if "native" mode |
| 54 | * is available, it will be faster and hence preferable. |
| 55 | * |
| 56 | * - MMC depends on a different chipselect management policy than the |
| 57 | * SPI interface currently supports for shared bus segments: it needs |
| 58 | * to issue multiple spi_message requests with the chipselect active, |
| 59 | * using the results of one message to decide the next one to issue. |
| 60 | * |
| 61 | * Pending updates to the programming interface, this driver expects |
| 62 | * that it not share the bus with other drivers (precluding conflicts). |
| 63 | * |
| 64 | * - We tell the controller to keep the chipselect active from the |
| 65 | * beginning of an mmc_host_ops.request until the end. So beware |
| 66 | * of SPI controller drivers that mis-handle the cs_change flag! |
| 67 | * |
| 68 | * However, many cards seem OK with chipselect flapping up/down |
| 69 | * during that time ... at least on unshared bus segments. |
| 70 | */ |
| 71 | |
| 72 | |
| 73 | /* |
| 74 | * Local protocol constants, internal to data block protocols. |
| 75 | */ |
| 76 | |
| 77 | /* Response tokens used to ack each block written: */ |
| 78 | #define SPI_MMC_RESPONSE_CODE(x) ((x) & 0x1f) |
| 79 | #define SPI_RESPONSE_ACCEPTED ((2 << 1)|1) |
| 80 | #define SPI_RESPONSE_CRC_ERR ((5 << 1)|1) |
| 81 | #define SPI_RESPONSE_WRITE_ERR ((6 << 1)|1) |
| 82 | |
| 83 | /* Read and write blocks start with these tokens and end with crc; |
| 84 | * on error, read tokens act like a subset of R2_SPI_* values. |
| 85 | */ |
| 86 | #define SPI_TOKEN_SINGLE 0xfe /* single block r/w, multiblock read */ |
| 87 | #define SPI_TOKEN_MULTI_WRITE 0xfc /* multiblock write */ |
| 88 | #define SPI_TOKEN_STOP_TRAN 0xfd /* terminate multiblock write */ |
| 89 | |
| 90 | #define MMC_SPI_BLOCKSIZE 512 |
| 91 | |
| 92 | |
| 93 | /* These fixed timeouts come from the latest SD specs, which say to ignore |
| 94 | * the CSD values. The R1B value is for card erase (e.g. the "I forgot the |
| 95 | * card's password" scenario); it's mostly applied to STOP_TRANSMISSION after |
| 96 | * reads which takes nowhere near that long. Older cards may be able to use |
| 97 | * shorter timeouts ... but why bother? |
| 98 | */ |
Wolfgang Muees | 56e303e | 2009-04-07 15:26:30 +0100 | [diff] [blame] | 99 | #define r1b_timeout (HZ * 3) |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 100 | |
Wolfgang Muees | 5cf20aa | 2009-04-08 10:14:07 +0100 | [diff] [blame] | 101 | /* One of the critical speed parameters is the amount of data which may |
| 102 | * be transfered in one command. If this value is too low, the SD card |
| 103 | * controller has to do multiple partial block writes (argggh!). With |
| 104 | * today (2008) SD cards there is little speed gain if we transfer more |
| 105 | * than 64 KBytes at a time. So use this value until there is any indication |
| 106 | * that we should do more here. |
| 107 | */ |
| 108 | #define MMC_SPI_BLOCKSATONCE 128 |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 109 | |
| 110 | /****************************************************************************/ |
| 111 | |
| 112 | /* |
| 113 | * Local Data Structures |
| 114 | */ |
| 115 | |
| 116 | /* "scratch" is per-{command,block} data exchanged with the card */ |
| 117 | struct scratch { |
| 118 | u8 status[29]; |
| 119 | u8 data_token; |
| 120 | __be16 crc_val; |
| 121 | }; |
| 122 | |
| 123 | struct mmc_spi_host { |
| 124 | struct mmc_host *mmc; |
| 125 | struct spi_device *spi; |
| 126 | |
| 127 | unsigned char power_mode; |
| 128 | u16 powerup_msecs; |
| 129 | |
| 130 | struct mmc_spi_platform_data *pdata; |
| 131 | |
| 132 | /* for bulk data transfers */ |
| 133 | struct spi_transfer token, t, crc, early_status; |
| 134 | struct spi_message m; |
| 135 | |
| 136 | /* for status readback */ |
| 137 | struct spi_transfer status; |
| 138 | struct spi_message readback; |
| 139 | |
| 140 | /* underlying DMA-aware controller, or null */ |
| 141 | struct device *dma_dev; |
| 142 | |
| 143 | /* buffer used for commands and for message "overhead" */ |
| 144 | struct scratch *data; |
| 145 | dma_addr_t data_dma; |
| 146 | |
| 147 | /* Specs say to write ones most of the time, even when the card |
| 148 | * has no need to read its input data; and many cards won't care. |
| 149 | * This is our source of those ones. |
| 150 | */ |
| 151 | void *ones; |
| 152 | dma_addr_t ones_dma; |
| 153 | }; |
| 154 | |
| 155 | |
| 156 | /****************************************************************************/ |
| 157 | |
| 158 | /* |
| 159 | * MMC-over-SPI protocol glue, used by the MMC stack interface |
| 160 | */ |
| 161 | |
| 162 | static inline int mmc_cs_off(struct mmc_spi_host *host) |
| 163 | { |
| 164 | /* chipselect will always be inactive after setup() */ |
| 165 | return spi_setup(host->spi); |
| 166 | } |
| 167 | |
| 168 | static int |
| 169 | mmc_spi_readbytes(struct mmc_spi_host *host, unsigned len) |
| 170 | { |
| 171 | int status; |
| 172 | |
| 173 | if (len > sizeof(*host->data)) { |
| 174 | WARN_ON(1); |
| 175 | return -EIO; |
| 176 | } |
| 177 | |
| 178 | host->status.len = len; |
| 179 | |
| 180 | if (host->dma_dev) |
| 181 | dma_sync_single_for_device(host->dma_dev, |
| 182 | host->data_dma, sizeof(*host->data), |
| 183 | DMA_FROM_DEVICE); |
| 184 | |
Ernst Schwab | 4751c1c | 2010-02-18 12:47:46 +0100 | [diff] [blame] | 185 | status = spi_sync_locked(host->spi, &host->readback); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 186 | |
| 187 | if (host->dma_dev) |
| 188 | dma_sync_single_for_cpu(host->dma_dev, |
| 189 | host->data_dma, sizeof(*host->data), |
| 190 | DMA_FROM_DEVICE); |
| 191 | |
| 192 | return status; |
| 193 | } |
| 194 | |
Wolfgang Muees | 56e303e | 2009-04-07 15:26:30 +0100 | [diff] [blame] | 195 | static int mmc_spi_skip(struct mmc_spi_host *host, unsigned long timeout, |
| 196 | unsigned n, u8 byte) |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 197 | { |
| 198 | u8 *cp = host->data->status; |
Wolfgang Muees | 56e303e | 2009-04-07 15:26:30 +0100 | [diff] [blame] | 199 | unsigned long start = jiffies; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 200 | |
| 201 | while (1) { |
| 202 | int status; |
| 203 | unsigned i; |
| 204 | |
| 205 | status = mmc_spi_readbytes(host, n); |
| 206 | if (status < 0) |
| 207 | return status; |
| 208 | |
| 209 | for (i = 0; i < n; i++) { |
| 210 | if (cp[i] != byte) |
| 211 | return cp[i]; |
| 212 | } |
| 213 | |
Wolfgang Muees | 56e303e | 2009-04-07 15:26:30 +0100 | [diff] [blame] | 214 | if (time_is_before_jiffies(start + timeout)) |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 215 | break; |
Wolfgang Muees | 56e303e | 2009-04-07 15:26:30 +0100 | [diff] [blame] | 216 | |
| 217 | /* If we need long timeouts, we may release the CPU. |
| 218 | * We use jiffies here because we want to have a relation |
| 219 | * between elapsed time and the blocking of the scheduler. |
| 220 | */ |
| 221 | if (time_is_before_jiffies(start+1)) |
| 222 | schedule(); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 223 | } |
| 224 | return -ETIMEDOUT; |
| 225 | } |
| 226 | |
| 227 | static inline int |
Wolfgang Muees | 56e303e | 2009-04-07 15:26:30 +0100 | [diff] [blame] | 228 | mmc_spi_wait_unbusy(struct mmc_spi_host *host, unsigned long timeout) |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 229 | { |
| 230 | return mmc_spi_skip(host, timeout, sizeof(host->data->status), 0); |
| 231 | } |
| 232 | |
Wolfgang Muees | 56e303e | 2009-04-07 15:26:30 +0100 | [diff] [blame] | 233 | static int mmc_spi_readtoken(struct mmc_spi_host *host, unsigned long timeout) |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 234 | { |
Matthew Fleming | 162350e | 2008-10-02 12:21:42 +0100 | [diff] [blame] | 235 | return mmc_spi_skip(host, timeout, 1, 0xff); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 236 | } |
| 237 | |
| 238 | |
| 239 | /* |
| 240 | * Note that for SPI, cmd->resp[0] is not the same data as "native" protocol |
| 241 | * hosts return! The low byte holds R1_SPI bits. The next byte may hold |
| 242 | * R2_SPI bits ... for SEND_STATUS, or after data read errors. |
| 243 | * |
| 244 | * cmd->resp[1] holds any four-byte response, for R3 (READ_OCR) and on |
| 245 | * newer cards R7 (IF_COND). |
| 246 | */ |
| 247 | |
| 248 | static char *maptype(struct mmc_command *cmd) |
| 249 | { |
| 250 | switch (mmc_spi_resp_type(cmd)) { |
| 251 | case MMC_RSP_SPI_R1: return "R1"; |
| 252 | case MMC_RSP_SPI_R1B: return "R1B"; |
| 253 | case MMC_RSP_SPI_R2: return "R2/R5"; |
| 254 | case MMC_RSP_SPI_R3: return "R3/R4/R7"; |
| 255 | default: return "?"; |
| 256 | } |
| 257 | } |
| 258 | |
| 259 | /* return zero, else negative errno after setting cmd->error */ |
| 260 | static int mmc_spi_response_get(struct mmc_spi_host *host, |
| 261 | struct mmc_command *cmd, int cs_on) |
| 262 | { |
| 263 | u8 *cp = host->data->status; |
| 264 | u8 *end = cp + host->t.len; |
| 265 | int value = 0; |
Wolfgang Muees | ab5a643 | 2009-04-08 09:48:58 +0100 | [diff] [blame] | 266 | int bitshift; |
| 267 | u8 leftover = 0; |
| 268 | unsigned short rotator; |
| 269 | int i; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 270 | char tag[32]; |
| 271 | |
| 272 | snprintf(tag, sizeof(tag), " ... CMD%d response SPI_%s", |
| 273 | cmd->opcode, maptype(cmd)); |
| 274 | |
| 275 | /* Except for data block reads, the whole response will already |
| 276 | * be stored in the scratch buffer. It's somewhere after the |
| 277 | * command and the first byte we read after it. We ignore that |
| 278 | * first byte. After STOP_TRANSMISSION command it may include |
| 279 | * two data bits, but otherwise it's all ones. |
| 280 | */ |
| 281 | cp += 8; |
| 282 | while (cp < end && *cp == 0xff) |
| 283 | cp++; |
| 284 | |
| 285 | /* Data block reads (R1 response types) may need more data... */ |
| 286 | if (cp == end) { |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 287 | cp = host->data->status; |
Wolfgang Muees | ab5a643 | 2009-04-08 09:48:58 +0100 | [diff] [blame] | 288 | end = cp+1; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 289 | |
| 290 | /* Card sends N(CR) (== 1..8) bytes of all-ones then one |
| 291 | * status byte ... and we already scanned 2 bytes. |
| 292 | * |
| 293 | * REVISIT block read paths use nasty byte-at-a-time I/O |
| 294 | * so it can always DMA directly into the target buffer. |
| 295 | * It'd probably be better to memcpy() the first chunk and |
| 296 | * avoid extra i/o calls... |
Wolfgang Muees | ea15ba5 | 2009-03-11 14:17:43 +0100 | [diff] [blame] | 297 | * |
| 298 | * Note we check for more than 8 bytes, because in practice, |
| 299 | * some SD cards are slow... |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 300 | */ |
Wolfgang Muees | ea15ba5 | 2009-03-11 14:17:43 +0100 | [diff] [blame] | 301 | for (i = 2; i < 16; i++) { |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 302 | value = mmc_spi_readbytes(host, 1); |
| 303 | if (value < 0) |
| 304 | goto done; |
| 305 | if (*cp != 0xff) |
| 306 | goto checkstatus; |
| 307 | } |
| 308 | value = -ETIMEDOUT; |
| 309 | goto done; |
| 310 | } |
| 311 | |
| 312 | checkstatus: |
Wolfgang Muees | ab5a643 | 2009-04-08 09:48:58 +0100 | [diff] [blame] | 313 | bitshift = 0; |
| 314 | if (*cp & 0x80) { |
| 315 | /* Houston, we have an ugly card with a bit-shifted response */ |
| 316 | rotator = *cp++ << 8; |
| 317 | /* read the next byte */ |
| 318 | if (cp == end) { |
| 319 | value = mmc_spi_readbytes(host, 1); |
| 320 | if (value < 0) |
| 321 | goto done; |
| 322 | cp = host->data->status; |
| 323 | end = cp+1; |
| 324 | } |
| 325 | rotator |= *cp++; |
| 326 | while (rotator & 0x8000) { |
| 327 | bitshift++; |
| 328 | rotator <<= 1; |
| 329 | } |
| 330 | cmd->resp[0] = rotator >> 8; |
| 331 | leftover = rotator; |
| 332 | } else { |
| 333 | cmd->resp[0] = *cp++; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 334 | } |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 335 | cmd->error = 0; |
| 336 | |
| 337 | /* Status byte: the entire seven-bit R1 response. */ |
| 338 | if (cmd->resp[0] != 0) { |
Wolfgang Muees | fdd858d | 2009-05-26 08:56:19 +0100 | [diff] [blame] | 339 | if ((R1_SPI_PARAMETER | R1_SPI_ADDRESS) |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 340 | & cmd->resp[0]) |
Wolfgang Muees | fdd858d | 2009-05-26 08:56:19 +0100 | [diff] [blame] | 341 | value = -EFAULT; /* Bad address */ |
| 342 | else if (R1_SPI_ILLEGAL_COMMAND & cmd->resp[0]) |
| 343 | value = -ENOSYS; /* Function not implemented */ |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 344 | else if (R1_SPI_COM_CRC & cmd->resp[0]) |
Wolfgang Muees | fdd858d | 2009-05-26 08:56:19 +0100 | [diff] [blame] | 345 | value = -EILSEQ; /* Illegal byte sequence */ |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 346 | else if ((R1_SPI_ERASE_SEQ | R1_SPI_ERASE_RESET) |
| 347 | & cmd->resp[0]) |
Wolfgang Muees | fdd858d | 2009-05-26 08:56:19 +0100 | [diff] [blame] | 348 | value = -EIO; /* I/O error */ |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 349 | /* else R1_SPI_IDLE, "it's resetting" */ |
| 350 | } |
| 351 | |
| 352 | switch (mmc_spi_resp_type(cmd)) { |
| 353 | |
| 354 | /* SPI R1B == R1 + busy; STOP_TRANSMISSION (for multiblock reads) |
| 355 | * and less-common stuff like various erase operations. |
| 356 | */ |
| 357 | case MMC_RSP_SPI_R1B: |
| 358 | /* maybe we read all the busy tokens already */ |
| 359 | while (cp < end && *cp == 0) |
| 360 | cp++; |
| 361 | if (cp == end) |
| 362 | mmc_spi_wait_unbusy(host, r1b_timeout); |
| 363 | break; |
| 364 | |
| 365 | /* SPI R2 == R1 + second status byte; SEND_STATUS |
| 366 | * SPI R5 == R1 + data byte; IO_RW_DIRECT |
| 367 | */ |
| 368 | case MMC_RSP_SPI_R2: |
Wolfgang Muees | ab5a643 | 2009-04-08 09:48:58 +0100 | [diff] [blame] | 369 | /* read the next byte */ |
| 370 | if (cp == end) { |
| 371 | value = mmc_spi_readbytes(host, 1); |
| 372 | if (value < 0) |
| 373 | goto done; |
| 374 | cp = host->data->status; |
| 375 | end = cp+1; |
| 376 | } |
| 377 | if (bitshift) { |
| 378 | rotator = leftover << 8; |
| 379 | rotator |= *cp << bitshift; |
| 380 | cmd->resp[0] |= (rotator & 0xFF00); |
| 381 | } else { |
| 382 | cmd->resp[0] |= *cp << 8; |
| 383 | } |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 384 | break; |
| 385 | |
| 386 | /* SPI R3, R4, or R7 == R1 + 4 bytes */ |
| 387 | case MMC_RSP_SPI_R3: |
Wolfgang Muees | ab5a643 | 2009-04-08 09:48:58 +0100 | [diff] [blame] | 388 | rotator = leftover << 8; |
| 389 | cmd->resp[1] = 0; |
| 390 | for (i = 0; i < 4; i++) { |
| 391 | cmd->resp[1] <<= 8; |
| 392 | /* read the next byte */ |
| 393 | if (cp == end) { |
| 394 | value = mmc_spi_readbytes(host, 1); |
| 395 | if (value < 0) |
| 396 | goto done; |
| 397 | cp = host->data->status; |
| 398 | end = cp+1; |
| 399 | } |
| 400 | if (bitshift) { |
| 401 | rotator |= *cp++ << bitshift; |
| 402 | cmd->resp[1] |= (rotator >> 8); |
| 403 | rotator <<= 8; |
| 404 | } else { |
| 405 | cmd->resp[1] |= *cp++; |
| 406 | } |
| 407 | } |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 408 | break; |
| 409 | |
| 410 | /* SPI R1 == just one status byte */ |
| 411 | case MMC_RSP_SPI_R1: |
| 412 | break; |
| 413 | |
| 414 | default: |
| 415 | dev_dbg(&host->spi->dev, "bad response type %04x\n", |
| 416 | mmc_spi_resp_type(cmd)); |
| 417 | if (value >= 0) |
| 418 | value = -EINVAL; |
| 419 | goto done; |
| 420 | } |
| 421 | |
| 422 | if (value < 0) |
| 423 | dev_dbg(&host->spi->dev, "%s: resp %04x %08x\n", |
| 424 | tag, cmd->resp[0], cmd->resp[1]); |
| 425 | |
| 426 | /* disable chipselect on errors and some success cases */ |
| 427 | if (value >= 0 && cs_on) |
| 428 | return value; |
| 429 | done: |
| 430 | if (value < 0) |
| 431 | cmd->error = value; |
| 432 | mmc_cs_off(host); |
| 433 | return value; |
| 434 | } |
| 435 | |
| 436 | /* Issue command and read its response. |
| 437 | * Returns zero on success, negative for error. |
| 438 | * |
| 439 | * On error, caller must cope with mmc core retry mechanism. That |
| 440 | * means immediate low-level resubmit, which affects the bus lock... |
| 441 | */ |
| 442 | static int |
| 443 | mmc_spi_command_send(struct mmc_spi_host *host, |
| 444 | struct mmc_request *mrq, |
| 445 | struct mmc_command *cmd, int cs_on) |
| 446 | { |
| 447 | struct scratch *data = host->data; |
| 448 | u8 *cp = data->status; |
| 449 | u32 arg = cmd->arg; |
| 450 | int status; |
| 451 | struct spi_transfer *t; |
| 452 | |
| 453 | /* We can handle most commands (except block reads) in one full |
| 454 | * duplex I/O operation before either starting the next transfer |
| 455 | * (data block or command) or else deselecting the card. |
| 456 | * |
| 457 | * First, write 7 bytes: |
| 458 | * - an all-ones byte to ensure the card is ready |
| 459 | * - opcode byte (plus start and transmission bits) |
| 460 | * - four bytes of big-endian argument |
| 461 | * - crc7 (plus end bit) ... always computed, it's cheap |
| 462 | * |
| 463 | * We init the whole buffer to all-ones, which is what we need |
| 464 | * to write while we're reading (later) response data. |
| 465 | */ |
| 466 | memset(cp++, 0xff, sizeof(data->status)); |
| 467 | |
| 468 | *cp++ = 0x40 | cmd->opcode; |
| 469 | *cp++ = (u8)(arg >> 24); |
| 470 | *cp++ = (u8)(arg >> 16); |
| 471 | *cp++ = (u8)(arg >> 8); |
| 472 | *cp++ = (u8)arg; |
| 473 | *cp++ = (crc7(0, &data->status[1], 5) << 1) | 0x01; |
| 474 | |
| 475 | /* Then, read up to 13 bytes (while writing all-ones): |
| 476 | * - N(CR) (== 1..8) bytes of all-ones |
| 477 | * - status byte (for all response types) |
| 478 | * - the rest of the response, either: |
| 479 | * + nothing, for R1 or R1B responses |
| 480 | * + second status byte, for R2 responses |
| 481 | * + four data bytes, for R3 and R7 responses |
| 482 | * |
| 483 | * Finally, read some more bytes ... in the nice cases we know in |
| 484 | * advance how many, and reading 1 more is always OK: |
| 485 | * - N(EC) (== 0..N) bytes of all-ones, before deselect/finish |
| 486 | * - N(RC) (== 1..N) bytes of all-ones, before next command |
| 487 | * - N(WR) (== 1..N) bytes of all-ones, before data write |
| 488 | * |
| 489 | * So in those cases one full duplex I/O of at most 21 bytes will |
| 490 | * handle the whole command, leaving the card ready to receive a |
| 491 | * data block or new command. We do that whenever we can, shaving |
| 492 | * CPU and IRQ costs (especially when using DMA or FIFOs). |
| 493 | * |
| 494 | * There are two other cases, where it's not generally practical |
| 495 | * to rely on a single I/O: |
| 496 | * |
| 497 | * - R1B responses need at least N(EC) bytes of all-zeroes. |
| 498 | * |
| 499 | * In this case we can *try* to fit it into one I/O, then |
| 500 | * maybe read more data later. |
| 501 | * |
| 502 | * - Data block reads are more troublesome, since a variable |
| 503 | * number of padding bytes precede the token and data. |
| 504 | * + N(CX) (== 0..8) bytes of all-ones, before CSD or CID |
| 505 | * + N(AC) (== 1..many) bytes of all-ones |
| 506 | * |
| 507 | * In this case we currently only have minimal speedups here: |
| 508 | * when N(CR) == 1 we can avoid I/O in response_get(). |
| 509 | */ |
| 510 | if (cs_on && (mrq->data->flags & MMC_DATA_READ)) { |
| 511 | cp += 2; /* min(N(CR)) + status */ |
| 512 | /* R1 */ |
| 513 | } else { |
| 514 | cp += 10; /* max(N(CR)) + status + min(N(RC),N(WR)) */ |
| 515 | if (cmd->flags & MMC_RSP_SPI_S2) /* R2/R5 */ |
| 516 | cp++; |
| 517 | else if (cmd->flags & MMC_RSP_SPI_B4) /* R3/R4/R7 */ |
| 518 | cp += 4; |
| 519 | else if (cmd->flags & MMC_RSP_BUSY) /* R1B */ |
| 520 | cp = data->status + sizeof(data->status); |
| 521 | /* else: R1 (most commands) */ |
| 522 | } |
| 523 | |
| 524 | dev_dbg(&host->spi->dev, " mmc_spi: CMD%d, resp %s\n", |
| 525 | cmd->opcode, maptype(cmd)); |
| 526 | |
| 527 | /* send command, leaving chipselect active */ |
| 528 | spi_message_init(&host->m); |
| 529 | |
| 530 | t = &host->t; |
| 531 | memset(t, 0, sizeof(*t)); |
| 532 | t->tx_buf = t->rx_buf = data->status; |
| 533 | t->tx_dma = t->rx_dma = host->data_dma; |
| 534 | t->len = cp - data->status; |
| 535 | t->cs_change = 1; |
| 536 | spi_message_add_tail(t, &host->m); |
| 537 | |
| 538 | if (host->dma_dev) { |
| 539 | host->m.is_dma_mapped = 1; |
| 540 | dma_sync_single_for_device(host->dma_dev, |
| 541 | host->data_dma, sizeof(*host->data), |
| 542 | DMA_BIDIRECTIONAL); |
| 543 | } |
Ernst Schwab | 4751c1c | 2010-02-18 12:47:46 +0100 | [diff] [blame] | 544 | status = spi_sync_locked(host->spi, &host->m); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 545 | |
| 546 | if (host->dma_dev) |
| 547 | dma_sync_single_for_cpu(host->dma_dev, |
| 548 | host->data_dma, sizeof(*host->data), |
| 549 | DMA_BIDIRECTIONAL); |
| 550 | if (status < 0) { |
| 551 | dev_dbg(&host->spi->dev, " ... write returned %d\n", status); |
| 552 | cmd->error = status; |
| 553 | return status; |
| 554 | } |
| 555 | |
| 556 | /* after no-data commands and STOP_TRANSMISSION, chipselect off */ |
| 557 | return mmc_spi_response_get(host, cmd, cs_on); |
| 558 | } |
| 559 | |
| 560 | /* Build data message with up to four separate transfers. For TX, we |
| 561 | * start by writing the data token. And in most cases, we finish with |
| 562 | * a status transfer. |
| 563 | * |
| 564 | * We always provide TX data for data and CRC. The MMC/SD protocol |
| 565 | * requires us to write ones; but Linux defaults to writing zeroes; |
| 566 | * so we explicitly initialize it to all ones on RX paths. |
| 567 | * |
| 568 | * We also handle DMA mapping, so the underlying SPI controller does |
| 569 | * not need to (re)do it for each message. |
| 570 | */ |
| 571 | static void |
| 572 | mmc_spi_setup_data_message( |
| 573 | struct mmc_spi_host *host, |
| 574 | int multiple, |
| 575 | enum dma_data_direction direction) |
| 576 | { |
| 577 | struct spi_transfer *t; |
| 578 | struct scratch *scratch = host->data; |
| 579 | dma_addr_t dma = host->data_dma; |
| 580 | |
| 581 | spi_message_init(&host->m); |
| 582 | if (dma) |
| 583 | host->m.is_dma_mapped = 1; |
| 584 | |
| 585 | /* for reads, readblock() skips 0xff bytes before finding |
| 586 | * the token; for writes, this transfer issues that token. |
| 587 | */ |
| 588 | if (direction == DMA_TO_DEVICE) { |
| 589 | t = &host->token; |
| 590 | memset(t, 0, sizeof(*t)); |
| 591 | t->len = 1; |
| 592 | if (multiple) |
| 593 | scratch->data_token = SPI_TOKEN_MULTI_WRITE; |
| 594 | else |
| 595 | scratch->data_token = SPI_TOKEN_SINGLE; |
| 596 | t->tx_buf = &scratch->data_token; |
| 597 | if (dma) |
| 598 | t->tx_dma = dma + offsetof(struct scratch, data_token); |
| 599 | spi_message_add_tail(t, &host->m); |
| 600 | } |
| 601 | |
| 602 | /* Body of transfer is buffer, then CRC ... |
| 603 | * either TX-only, or RX with TX-ones. |
| 604 | */ |
| 605 | t = &host->t; |
| 606 | memset(t, 0, sizeof(*t)); |
| 607 | t->tx_buf = host->ones; |
| 608 | t->tx_dma = host->ones_dma; |
| 609 | /* length and actual buffer info are written later */ |
| 610 | spi_message_add_tail(t, &host->m); |
| 611 | |
| 612 | t = &host->crc; |
| 613 | memset(t, 0, sizeof(*t)); |
| 614 | t->len = 2; |
| 615 | if (direction == DMA_TO_DEVICE) { |
| 616 | /* the actual CRC may get written later */ |
| 617 | t->tx_buf = &scratch->crc_val; |
| 618 | if (dma) |
| 619 | t->tx_dma = dma + offsetof(struct scratch, crc_val); |
| 620 | } else { |
| 621 | t->tx_buf = host->ones; |
| 622 | t->tx_dma = host->ones_dma; |
| 623 | t->rx_buf = &scratch->crc_val; |
| 624 | if (dma) |
| 625 | t->rx_dma = dma + offsetof(struct scratch, crc_val); |
| 626 | } |
| 627 | spi_message_add_tail(t, &host->m); |
| 628 | |
| 629 | /* |
| 630 | * A single block read is followed by N(EC) [0+] all-ones bytes |
| 631 | * before deselect ... don't bother. |
| 632 | * |
| 633 | * Multiblock reads are followed by N(AC) [1+] all-ones bytes before |
| 634 | * the next block is read, or a STOP_TRANSMISSION is issued. We'll |
| 635 | * collect that single byte, so readblock() doesn't need to. |
| 636 | * |
| 637 | * For a write, the one-byte data response follows immediately, then |
| 638 | * come zero or more busy bytes, then N(WR) [1+] all-ones bytes. |
| 639 | * Then single block reads may deselect, and multiblock ones issue |
| 640 | * the next token (next data block, or STOP_TRAN). We can try to |
| 641 | * minimize I/O ops by using a single read to collect end-of-busy. |
| 642 | */ |
| 643 | if (multiple || direction == DMA_TO_DEVICE) { |
| 644 | t = &host->early_status; |
| 645 | memset(t, 0, sizeof(*t)); |
| 646 | t->len = (direction == DMA_TO_DEVICE) |
| 647 | ? sizeof(scratch->status) |
| 648 | : 1; |
| 649 | t->tx_buf = host->ones; |
| 650 | t->tx_dma = host->ones_dma; |
| 651 | t->rx_buf = scratch->status; |
| 652 | if (dma) |
| 653 | t->rx_dma = dma + offsetof(struct scratch, status); |
| 654 | t->cs_change = 1; |
| 655 | spi_message_add_tail(t, &host->m); |
| 656 | } |
| 657 | } |
| 658 | |
| 659 | /* |
| 660 | * Write one block: |
| 661 | * - caller handled preceding N(WR) [1+] all-ones bytes |
| 662 | * - data block |
| 663 | * + token |
| 664 | * + data bytes |
| 665 | * + crc16 |
| 666 | * - an all-ones byte ... card writes a data-response byte |
| 667 | * - followed by N(EC) [0+] all-ones bytes, card writes zero/'busy' |
| 668 | * |
| 669 | * Return negative errno, else success. |
| 670 | */ |
| 671 | static int |
Matthew Fleming | 162350e | 2008-10-02 12:21:42 +0100 | [diff] [blame] | 672 | mmc_spi_writeblock(struct mmc_spi_host *host, struct spi_transfer *t, |
Wolfgang Muees | 56e303e | 2009-04-07 15:26:30 +0100 | [diff] [blame] | 673 | unsigned long timeout) |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 674 | { |
| 675 | struct spi_device *spi = host->spi; |
| 676 | int status, i; |
| 677 | struct scratch *scratch = host->data; |
Wolfgang Muees | f079a8f | 2009-03-16 12:23:03 +0100 | [diff] [blame] | 678 | u32 pattern; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 679 | |
| 680 | if (host->mmc->use_spi_crc) |
| 681 | scratch->crc_val = cpu_to_be16( |
| 682 | crc_itu_t(0, t->tx_buf, t->len)); |
| 683 | if (host->dma_dev) |
| 684 | dma_sync_single_for_device(host->dma_dev, |
| 685 | host->data_dma, sizeof(*scratch), |
| 686 | DMA_BIDIRECTIONAL); |
| 687 | |
Ernst Schwab | 4751c1c | 2010-02-18 12:47:46 +0100 | [diff] [blame] | 688 | status = spi_sync_locked(spi, &host->m); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 689 | |
| 690 | if (status != 0) { |
| 691 | dev_dbg(&spi->dev, "write error (%d)\n", status); |
| 692 | return status; |
| 693 | } |
| 694 | |
| 695 | if (host->dma_dev) |
| 696 | dma_sync_single_for_cpu(host->dma_dev, |
| 697 | host->data_dma, sizeof(*scratch), |
| 698 | DMA_BIDIRECTIONAL); |
| 699 | |
| 700 | /* |
| 701 | * Get the transmission data-response reply. It must follow |
| 702 | * immediately after the data block we transferred. This reply |
| 703 | * doesn't necessarily tell whether the write operation succeeded; |
| 704 | * it just says if the transmission was ok and whether *earlier* |
| 705 | * writes succeeded; see the standard. |
Wolfgang Muees | f079a8f | 2009-03-16 12:23:03 +0100 | [diff] [blame] | 706 | * |
| 707 | * In practice, there are (even modern SDHC-)cards which are late |
| 708 | * in sending the response, and miss the time frame by a few bits, |
| 709 | * so we have to cope with this situation and check the response |
| 710 | * bit-by-bit. Arggh!!! |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 711 | */ |
Wolfgang Muees | f079a8f | 2009-03-16 12:23:03 +0100 | [diff] [blame] | 712 | pattern = scratch->status[0] << 24; |
| 713 | pattern |= scratch->status[1] << 16; |
| 714 | pattern |= scratch->status[2] << 8; |
| 715 | pattern |= scratch->status[3]; |
| 716 | |
| 717 | /* First 3 bit of pattern are undefined */ |
| 718 | pattern |= 0xE0000000; |
| 719 | |
| 720 | /* left-adjust to leading 0 bit */ |
| 721 | while (pattern & 0x80000000) |
| 722 | pattern <<= 1; |
| 723 | /* right-adjust for pattern matching. Code is in bit 4..0 now. */ |
| 724 | pattern >>= 27; |
| 725 | |
| 726 | switch (pattern) { |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 727 | case SPI_RESPONSE_ACCEPTED: |
| 728 | status = 0; |
| 729 | break; |
| 730 | case SPI_RESPONSE_CRC_ERR: |
| 731 | /* host shall then issue MMC_STOP_TRANSMISSION */ |
| 732 | status = -EILSEQ; |
| 733 | break; |
| 734 | case SPI_RESPONSE_WRITE_ERR: |
| 735 | /* host shall then issue MMC_STOP_TRANSMISSION, |
| 736 | * and should MMC_SEND_STATUS to sort it out |
| 737 | */ |
| 738 | status = -EIO; |
| 739 | break; |
| 740 | default: |
| 741 | status = -EPROTO; |
| 742 | break; |
| 743 | } |
| 744 | if (status != 0) { |
| 745 | dev_dbg(&spi->dev, "write error %02x (%d)\n", |
| 746 | scratch->status[0], status); |
| 747 | return status; |
| 748 | } |
| 749 | |
| 750 | t->tx_buf += t->len; |
| 751 | if (host->dma_dev) |
| 752 | t->tx_dma += t->len; |
| 753 | |
| 754 | /* Return when not busy. If we didn't collect that status yet, |
| 755 | * we'll need some more I/O. |
| 756 | */ |
Wolfgang Muees | f079a8f | 2009-03-16 12:23:03 +0100 | [diff] [blame] | 757 | for (i = 4; i < sizeof(scratch->status); i++) { |
| 758 | /* card is non-busy if the most recent bit is 1 */ |
| 759 | if (scratch->status[i] & 0x01) |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 760 | return 0; |
| 761 | } |
Matthew Fleming | 162350e | 2008-10-02 12:21:42 +0100 | [diff] [blame] | 762 | return mmc_spi_wait_unbusy(host, timeout); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 763 | } |
| 764 | |
| 765 | /* |
| 766 | * Read one block: |
| 767 | * - skip leading all-ones bytes ... either |
| 768 | * + N(AC) [1..f(clock,CSD)] usually, else |
| 769 | * + N(CX) [0..8] when reading CSD or CID |
| 770 | * - data block |
| 771 | * + token ... if error token, no data or crc |
| 772 | * + data bytes |
| 773 | * + crc16 |
| 774 | * |
| 775 | * After single block reads, we're done; N(EC) [0+] all-ones bytes follow |
| 776 | * before dropping chipselect. |
| 777 | * |
| 778 | * For multiblock reads, caller either reads the next block or issues a |
| 779 | * STOP_TRANSMISSION command. |
| 780 | */ |
| 781 | static int |
Matthew Fleming | 162350e | 2008-10-02 12:21:42 +0100 | [diff] [blame] | 782 | mmc_spi_readblock(struct mmc_spi_host *host, struct spi_transfer *t, |
Wolfgang Muees | 56e303e | 2009-04-07 15:26:30 +0100 | [diff] [blame] | 783 | unsigned long timeout) |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 784 | { |
| 785 | struct spi_device *spi = host->spi; |
| 786 | int status; |
| 787 | struct scratch *scratch = host->data; |
Wolfgang Muees | ab5a643 | 2009-04-08 09:48:58 +0100 | [diff] [blame] | 788 | unsigned int bitshift; |
| 789 | u8 leftover; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 790 | |
| 791 | /* At least one SD card sends an all-zeroes byte when N(CX) |
| 792 | * applies, before the all-ones bytes ... just cope with that. |
| 793 | */ |
| 794 | status = mmc_spi_readbytes(host, 1); |
| 795 | if (status < 0) |
| 796 | return status; |
| 797 | status = scratch->status[0]; |
| 798 | if (status == 0xff || status == 0) |
Matthew Fleming | 162350e | 2008-10-02 12:21:42 +0100 | [diff] [blame] | 799 | status = mmc_spi_readtoken(host, timeout); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 800 | |
Wolfgang Muees | ab5a643 | 2009-04-08 09:48:58 +0100 | [diff] [blame] | 801 | if (status < 0) { |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 802 | dev_dbg(&spi->dev, "read error %02x (%d)\n", status, status); |
Wolfgang Muees | ab5a643 | 2009-04-08 09:48:58 +0100 | [diff] [blame] | 803 | return status; |
| 804 | } |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 805 | |
Wolfgang Muees | ab5a643 | 2009-04-08 09:48:58 +0100 | [diff] [blame] | 806 | /* The token may be bit-shifted... |
| 807 | * the first 0-bit precedes the data stream. |
| 808 | */ |
| 809 | bitshift = 7; |
| 810 | while (status & 0x80) { |
| 811 | status <<= 1; |
| 812 | bitshift--; |
| 813 | } |
| 814 | leftover = status << 1; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 815 | |
Wolfgang Muees | ab5a643 | 2009-04-08 09:48:58 +0100 | [diff] [blame] | 816 | if (host->dma_dev) { |
| 817 | dma_sync_single_for_device(host->dma_dev, |
| 818 | host->data_dma, sizeof(*scratch), |
| 819 | DMA_BIDIRECTIONAL); |
| 820 | dma_sync_single_for_device(host->dma_dev, |
| 821 | t->rx_dma, t->len, |
| 822 | DMA_FROM_DEVICE); |
| 823 | } |
| 824 | |
Ernst Schwab | 4751c1c | 2010-02-18 12:47:46 +0100 | [diff] [blame] | 825 | status = spi_sync_locked(spi, &host->m); |
Wolfgang Muees | ab5a643 | 2009-04-08 09:48:58 +0100 | [diff] [blame] | 826 | |
| 827 | if (host->dma_dev) { |
| 828 | dma_sync_single_for_cpu(host->dma_dev, |
| 829 | host->data_dma, sizeof(*scratch), |
| 830 | DMA_BIDIRECTIONAL); |
| 831 | dma_sync_single_for_cpu(host->dma_dev, |
| 832 | t->rx_dma, t->len, |
| 833 | DMA_FROM_DEVICE); |
| 834 | } |
| 835 | |
| 836 | if (bitshift) { |
| 837 | /* Walk through the data and the crc and do |
| 838 | * all the magic to get byte-aligned data. |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 839 | */ |
Wolfgang Muees | ab5a643 | 2009-04-08 09:48:58 +0100 | [diff] [blame] | 840 | u8 *cp = t->rx_buf; |
| 841 | unsigned int len; |
| 842 | unsigned int bitright = 8 - bitshift; |
| 843 | u8 temp; |
| 844 | for (len = t->len; len; len--) { |
| 845 | temp = *cp; |
| 846 | *cp++ = leftover | (temp >> bitshift); |
| 847 | leftover = temp << bitright; |
| 848 | } |
| 849 | cp = (u8 *) &scratch->crc_val; |
| 850 | temp = *cp; |
| 851 | *cp++ = leftover | (temp >> bitshift); |
| 852 | leftover = temp << bitright; |
| 853 | temp = *cp; |
| 854 | *cp = leftover | (temp >> bitshift); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 855 | } |
| 856 | |
| 857 | if (host->mmc->use_spi_crc) { |
| 858 | u16 crc = crc_itu_t(0, t->rx_buf, t->len); |
| 859 | |
| 860 | be16_to_cpus(&scratch->crc_val); |
| 861 | if (scratch->crc_val != crc) { |
| 862 | dev_dbg(&spi->dev, "read - crc error: crc_val=0x%04x, " |
| 863 | "computed=0x%04x len=%d\n", |
| 864 | scratch->crc_val, crc, t->len); |
| 865 | return -EILSEQ; |
| 866 | } |
| 867 | } |
| 868 | |
| 869 | t->rx_buf += t->len; |
| 870 | if (host->dma_dev) |
| 871 | t->rx_dma += t->len; |
| 872 | |
| 873 | return 0; |
| 874 | } |
| 875 | |
| 876 | /* |
| 877 | * An MMC/SD data stage includes one or more blocks, optional CRCs, |
| 878 | * and inline handshaking. That handhaking makes it unlike most |
| 879 | * other SPI protocol stacks. |
| 880 | */ |
| 881 | static void |
| 882 | mmc_spi_data_do(struct mmc_spi_host *host, struct mmc_command *cmd, |
| 883 | struct mmc_data *data, u32 blk_size) |
| 884 | { |
| 885 | struct spi_device *spi = host->spi; |
| 886 | struct device *dma_dev = host->dma_dev; |
| 887 | struct spi_transfer *t; |
| 888 | enum dma_data_direction direction; |
| 889 | struct scatterlist *sg; |
| 890 | unsigned n_sg; |
| 891 | int multiple = (data->blocks > 1); |
Matthew Fleming | 162350e | 2008-10-02 12:21:42 +0100 | [diff] [blame] | 892 | u32 clock_rate; |
Wolfgang Muees | 56e303e | 2009-04-07 15:26:30 +0100 | [diff] [blame] | 893 | unsigned long timeout; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 894 | |
| 895 | if (data->flags & MMC_DATA_READ) |
| 896 | direction = DMA_FROM_DEVICE; |
| 897 | else |
| 898 | direction = DMA_TO_DEVICE; |
| 899 | mmc_spi_setup_data_message(host, multiple, direction); |
| 900 | t = &host->t; |
| 901 | |
Matthew Fleming | 162350e | 2008-10-02 12:21:42 +0100 | [diff] [blame] | 902 | if (t->speed_hz) |
| 903 | clock_rate = t->speed_hz; |
| 904 | else |
| 905 | clock_rate = spi->max_speed_hz; |
| 906 | |
Wolfgang Muees | 56e303e | 2009-04-07 15:26:30 +0100 | [diff] [blame] | 907 | timeout = data->timeout_ns + |
| 908 | data->timeout_clks * 1000000 / clock_rate; |
| 909 | timeout = usecs_to_jiffies((unsigned int)(timeout / 1000)) + 1; |
Matthew Fleming | 162350e | 2008-10-02 12:21:42 +0100 | [diff] [blame] | 910 | |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 911 | /* Handle scatterlist segments one at a time, with synch for |
| 912 | * each 512-byte block |
| 913 | */ |
| 914 | for (sg = data->sg, n_sg = data->sg_len; n_sg; n_sg--, sg++) { |
| 915 | int status = 0; |
| 916 | dma_addr_t dma_addr = 0; |
| 917 | void *kmap_addr; |
| 918 | unsigned length = sg->length; |
| 919 | enum dma_data_direction dir = direction; |
| 920 | |
| 921 | /* set up dma mapping for controller drivers that might |
| 922 | * use DMA ... though they may fall back to PIO |
| 923 | */ |
| 924 | if (dma_dev) { |
| 925 | /* never invalidate whole *shared* pages ... */ |
| 926 | if ((sg->offset != 0 || length != PAGE_SIZE) |
| 927 | && dir == DMA_FROM_DEVICE) |
| 928 | dir = DMA_BIDIRECTIONAL; |
| 929 | |
Jens Axboe | 45711f1 | 2007-10-22 21:19:53 +0200 | [diff] [blame] | 930 | dma_addr = dma_map_page(dma_dev, sg_page(sg), 0, |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 931 | PAGE_SIZE, dir); |
| 932 | if (direction == DMA_TO_DEVICE) |
| 933 | t->tx_dma = dma_addr + sg->offset; |
| 934 | else |
| 935 | t->rx_dma = dma_addr + sg->offset; |
| 936 | } |
| 937 | |
| 938 | /* allow pio too; we don't allow highmem */ |
Jens Axboe | 45711f1 | 2007-10-22 21:19:53 +0200 | [diff] [blame] | 939 | kmap_addr = kmap(sg_page(sg)); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 940 | if (direction == DMA_TO_DEVICE) |
| 941 | t->tx_buf = kmap_addr + sg->offset; |
| 942 | else |
| 943 | t->rx_buf = kmap_addr + sg->offset; |
| 944 | |
| 945 | /* transfer each block, and update request status */ |
| 946 | while (length) { |
| 947 | t->len = min(length, blk_size); |
| 948 | |
| 949 | dev_dbg(&host->spi->dev, |
| 950 | " mmc_spi: %s block, %d bytes\n", |
| 951 | (direction == DMA_TO_DEVICE) |
| 952 | ? "write" |
| 953 | : "read", |
| 954 | t->len); |
| 955 | |
| 956 | if (direction == DMA_TO_DEVICE) |
Matthew Fleming | 162350e | 2008-10-02 12:21:42 +0100 | [diff] [blame] | 957 | status = mmc_spi_writeblock(host, t, timeout); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 958 | else |
Matthew Fleming | 162350e | 2008-10-02 12:21:42 +0100 | [diff] [blame] | 959 | status = mmc_spi_readblock(host, t, timeout); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 960 | if (status < 0) |
| 961 | break; |
| 962 | |
| 963 | data->bytes_xfered += t->len; |
| 964 | length -= t->len; |
| 965 | |
| 966 | if (!multiple) |
| 967 | break; |
| 968 | } |
| 969 | |
| 970 | /* discard mappings */ |
| 971 | if (direction == DMA_FROM_DEVICE) |
Jens Axboe | 45711f1 | 2007-10-22 21:19:53 +0200 | [diff] [blame] | 972 | flush_kernel_dcache_page(sg_page(sg)); |
| 973 | kunmap(sg_page(sg)); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 974 | if (dma_dev) |
| 975 | dma_unmap_page(dma_dev, dma_addr, PAGE_SIZE, dir); |
| 976 | |
| 977 | if (status < 0) { |
| 978 | data->error = status; |
| 979 | dev_dbg(&spi->dev, "%s status %d\n", |
| 980 | (direction == DMA_TO_DEVICE) |
| 981 | ? "write" : "read", |
| 982 | status); |
| 983 | break; |
| 984 | } |
| 985 | } |
| 986 | |
| 987 | /* NOTE some docs describe an MMC-only SET_BLOCK_COUNT (CMD23) that |
| 988 | * can be issued before multiblock writes. Unlike its more widely |
| 989 | * documented analogue for SD cards (SET_WR_BLK_ERASE_COUNT, ACMD23), |
| 990 | * that can affect the STOP_TRAN logic. Complete (and current) |
| 991 | * MMC specs should sort that out before Linux starts using CMD23. |
| 992 | */ |
| 993 | if (direction == DMA_TO_DEVICE && multiple) { |
| 994 | struct scratch *scratch = host->data; |
| 995 | int tmp; |
| 996 | const unsigned statlen = sizeof(scratch->status); |
| 997 | |
| 998 | dev_dbg(&spi->dev, " mmc_spi: STOP_TRAN\n"); |
| 999 | |
| 1000 | /* Tweak the per-block message we set up earlier by morphing |
| 1001 | * it to hold single buffer with the token followed by some |
| 1002 | * all-ones bytes ... skip N(BR) (0..1), scan the rest for |
| 1003 | * "not busy any longer" status, and leave chip selected. |
| 1004 | */ |
| 1005 | INIT_LIST_HEAD(&host->m.transfers); |
| 1006 | list_add(&host->early_status.transfer_list, |
| 1007 | &host->m.transfers); |
| 1008 | |
| 1009 | memset(scratch->status, 0xff, statlen); |
| 1010 | scratch->status[0] = SPI_TOKEN_STOP_TRAN; |
| 1011 | |
| 1012 | host->early_status.tx_buf = host->early_status.rx_buf; |
| 1013 | host->early_status.tx_dma = host->early_status.rx_dma; |
| 1014 | host->early_status.len = statlen; |
| 1015 | |
| 1016 | if (host->dma_dev) |
| 1017 | dma_sync_single_for_device(host->dma_dev, |
| 1018 | host->data_dma, sizeof(*scratch), |
| 1019 | DMA_BIDIRECTIONAL); |
| 1020 | |
Ernst Schwab | 4751c1c | 2010-02-18 12:47:46 +0100 | [diff] [blame] | 1021 | tmp = spi_sync_locked(spi, &host->m); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1022 | |
| 1023 | if (host->dma_dev) |
| 1024 | dma_sync_single_for_cpu(host->dma_dev, |
| 1025 | host->data_dma, sizeof(*scratch), |
| 1026 | DMA_BIDIRECTIONAL); |
| 1027 | |
| 1028 | if (tmp < 0) { |
| 1029 | if (!data->error) |
| 1030 | data->error = tmp; |
| 1031 | return; |
| 1032 | } |
| 1033 | |
| 1034 | /* Ideally we collected "not busy" status with one I/O, |
| 1035 | * avoiding wasteful byte-at-a-time scanning... but more |
| 1036 | * I/O is often needed. |
| 1037 | */ |
| 1038 | for (tmp = 2; tmp < statlen; tmp++) { |
| 1039 | if (scratch->status[tmp] != 0) |
| 1040 | return; |
| 1041 | } |
Matthew Fleming | 162350e | 2008-10-02 12:21:42 +0100 | [diff] [blame] | 1042 | tmp = mmc_spi_wait_unbusy(host, timeout); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1043 | if (tmp < 0 && !data->error) |
| 1044 | data->error = tmp; |
| 1045 | } |
| 1046 | } |
| 1047 | |
| 1048 | /****************************************************************************/ |
| 1049 | |
| 1050 | /* |
| 1051 | * MMC driver implementation -- the interface to the MMC stack |
| 1052 | */ |
| 1053 | |
| 1054 | static void mmc_spi_request(struct mmc_host *mmc, struct mmc_request *mrq) |
| 1055 | { |
| 1056 | struct mmc_spi_host *host = mmc_priv(mmc); |
| 1057 | int status = -EINVAL; |
Sonic Zhang | 061c6c8 | 2010-07-12 15:50:56 +0800 | [diff] [blame^] | 1058 | int crc_retry = 5; |
| 1059 | struct mmc_command stop; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1060 | |
| 1061 | #ifdef DEBUG |
| 1062 | /* MMC core and layered drivers *MUST* issue SPI-aware commands */ |
| 1063 | { |
| 1064 | struct mmc_command *cmd; |
| 1065 | int invalid = 0; |
| 1066 | |
| 1067 | cmd = mrq->cmd; |
| 1068 | if (!mmc_spi_resp_type(cmd)) { |
| 1069 | dev_dbg(&host->spi->dev, "bogus command\n"); |
| 1070 | cmd->error = -EINVAL; |
| 1071 | invalid = 1; |
| 1072 | } |
| 1073 | |
| 1074 | cmd = mrq->stop; |
| 1075 | if (cmd && !mmc_spi_resp_type(cmd)) { |
| 1076 | dev_dbg(&host->spi->dev, "bogus STOP command\n"); |
| 1077 | cmd->error = -EINVAL; |
| 1078 | invalid = 1; |
| 1079 | } |
| 1080 | |
| 1081 | if (invalid) { |
| 1082 | dump_stack(); |
| 1083 | mmc_request_done(host->mmc, mrq); |
| 1084 | return; |
| 1085 | } |
| 1086 | } |
| 1087 | #endif |
| 1088 | |
Ernst Schwab | 4751c1c | 2010-02-18 12:47:46 +0100 | [diff] [blame] | 1089 | /* request exclusive bus access */ |
| 1090 | spi_bus_lock(host->spi->master); |
| 1091 | |
Sonic Zhang | 061c6c8 | 2010-07-12 15:50:56 +0800 | [diff] [blame^] | 1092 | crc_recover: |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1093 | /* issue command; then optionally data and stop */ |
| 1094 | status = mmc_spi_command_send(host, mrq, mrq->cmd, mrq->data != NULL); |
| 1095 | if (status == 0 && mrq->data) { |
| 1096 | mmc_spi_data_do(host, mrq->cmd, mrq->data, mrq->data->blksz); |
Sonic Zhang | 061c6c8 | 2010-07-12 15:50:56 +0800 | [diff] [blame^] | 1097 | |
| 1098 | /* |
| 1099 | * The SPI bus is not always reliable for large data transfers. |
| 1100 | * If an occasional crc error is reported by the SD device with |
| 1101 | * data read/write over SPI, it may be recovered by repeating |
| 1102 | * the last SD command again. The retry count is set to 5 to |
| 1103 | * ensure the driver passes stress tests. |
| 1104 | */ |
| 1105 | if (mrq->data->error == -EILSEQ && crc_retry) { |
| 1106 | stop.opcode = MMC_STOP_TRANSMISSION; |
| 1107 | stop.arg = 0; |
| 1108 | stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC; |
| 1109 | status = mmc_spi_command_send(host, mrq, &stop, 0); |
| 1110 | crc_retry--; |
| 1111 | mrq->data->error = 0; |
| 1112 | goto crc_recover; |
| 1113 | } |
| 1114 | |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1115 | if (mrq->stop) |
| 1116 | status = mmc_spi_command_send(host, mrq, mrq->stop, 0); |
| 1117 | else |
| 1118 | mmc_cs_off(host); |
| 1119 | } |
| 1120 | |
Ernst Schwab | 4751c1c | 2010-02-18 12:47:46 +0100 | [diff] [blame] | 1121 | /* release the bus */ |
| 1122 | spi_bus_unlock(host->spi->master); |
| 1123 | |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1124 | mmc_request_done(host->mmc, mrq); |
| 1125 | } |
| 1126 | |
| 1127 | /* See Section 6.4.1, in SD "Simplified Physical Layer Specification 2.0" |
| 1128 | * |
| 1129 | * NOTE that here we can't know that the card has just been powered up; |
| 1130 | * not all MMC/SD sockets support power switching. |
| 1131 | * |
| 1132 | * FIXME when the card is still in SPI mode, e.g. from a previous kernel, |
| 1133 | * this doesn't seem to do the right thing at all... |
| 1134 | */ |
| 1135 | static void mmc_spi_initsequence(struct mmc_spi_host *host) |
| 1136 | { |
| 1137 | /* Try to be very sure any previous command has completed; |
| 1138 | * wait till not-busy, skip debris from any old commands. |
| 1139 | */ |
| 1140 | mmc_spi_wait_unbusy(host, r1b_timeout); |
| 1141 | mmc_spi_readbytes(host, 10); |
| 1142 | |
| 1143 | /* |
| 1144 | * Do a burst with chipselect active-high. We need to do this to |
| 1145 | * meet the requirement of 74 clock cycles with both chipselect |
| 1146 | * and CMD (MOSI) high before CMD0 ... after the card has been |
| 1147 | * powered up to Vdd(min), and so is ready to take commands. |
| 1148 | * |
| 1149 | * Some cards are particularly needy of this (e.g. Viking "SD256") |
| 1150 | * while most others don't seem to care. |
| 1151 | * |
| 1152 | * Note that this is one of the places MMC/SD plays games with the |
| 1153 | * SPI protocol. Another is that when chipselect is released while |
| 1154 | * the card returns BUSY status, the clock must issue several cycles |
| 1155 | * with chipselect high before the card will stop driving its output. |
| 1156 | */ |
| 1157 | host->spi->mode |= SPI_CS_HIGH; |
| 1158 | if (spi_setup(host->spi) != 0) { |
| 1159 | /* Just warn; most cards work without it. */ |
| 1160 | dev_warn(&host->spi->dev, |
| 1161 | "can't change chip-select polarity\n"); |
| 1162 | host->spi->mode &= ~SPI_CS_HIGH; |
| 1163 | } else { |
| 1164 | mmc_spi_readbytes(host, 18); |
| 1165 | |
| 1166 | host->spi->mode &= ~SPI_CS_HIGH; |
| 1167 | if (spi_setup(host->spi) != 0) { |
| 1168 | /* Wot, we can't get the same setup we had before? */ |
| 1169 | dev_err(&host->spi->dev, |
| 1170 | "can't restore chip-select polarity\n"); |
| 1171 | } |
| 1172 | } |
| 1173 | } |
| 1174 | |
| 1175 | static char *mmc_powerstring(u8 power_mode) |
| 1176 | { |
| 1177 | switch (power_mode) { |
| 1178 | case MMC_POWER_OFF: return "off"; |
| 1179 | case MMC_POWER_UP: return "up"; |
| 1180 | case MMC_POWER_ON: return "on"; |
| 1181 | } |
| 1182 | return "?"; |
| 1183 | } |
| 1184 | |
| 1185 | static void mmc_spi_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) |
| 1186 | { |
| 1187 | struct mmc_spi_host *host = mmc_priv(mmc); |
| 1188 | |
| 1189 | if (host->power_mode != ios->power_mode) { |
| 1190 | int canpower; |
| 1191 | |
| 1192 | canpower = host->pdata && host->pdata->setpower; |
| 1193 | |
| 1194 | dev_dbg(&host->spi->dev, "mmc_spi: power %s (%d)%s\n", |
| 1195 | mmc_powerstring(ios->power_mode), |
| 1196 | ios->vdd, |
| 1197 | canpower ? ", can switch" : ""); |
| 1198 | |
| 1199 | /* switch power on/off if possible, accounting for |
| 1200 | * max 250msec powerup time if needed. |
| 1201 | */ |
| 1202 | if (canpower) { |
| 1203 | switch (ios->power_mode) { |
| 1204 | case MMC_POWER_OFF: |
| 1205 | case MMC_POWER_UP: |
| 1206 | host->pdata->setpower(&host->spi->dev, |
| 1207 | ios->vdd); |
| 1208 | if (ios->power_mode == MMC_POWER_UP) |
| 1209 | msleep(host->powerup_msecs); |
| 1210 | } |
| 1211 | } |
| 1212 | |
| 1213 | /* See 6.4.1 in the simplified SD card physical spec 2.0 */ |
| 1214 | if (ios->power_mode == MMC_POWER_ON) |
| 1215 | mmc_spi_initsequence(host); |
| 1216 | |
| 1217 | /* If powering down, ground all card inputs to avoid power |
| 1218 | * delivery from data lines! On a shared SPI bus, this |
| 1219 | * will probably be temporary; 6.4.2 of the simplified SD |
| 1220 | * spec says this must last at least 1msec. |
| 1221 | * |
| 1222 | * - Clock low means CPOL 0, e.g. mode 0 |
| 1223 | * - MOSI low comes from writing zero |
| 1224 | * - Chipselect is usually active low... |
| 1225 | */ |
| 1226 | if (canpower && ios->power_mode == MMC_POWER_OFF) { |
| 1227 | int mres; |
Jan Nikitenko | 1685a03 | 2008-07-24 01:27:07 +0200 | [diff] [blame] | 1228 | u8 nullbyte = 0; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1229 | |
| 1230 | host->spi->mode &= ~(SPI_CPOL|SPI_CPHA); |
| 1231 | mres = spi_setup(host->spi); |
| 1232 | if (mres < 0) |
| 1233 | dev_dbg(&host->spi->dev, |
| 1234 | "switch to SPI mode 0 failed\n"); |
| 1235 | |
Jan Nikitenko | 1685a03 | 2008-07-24 01:27:07 +0200 | [diff] [blame] | 1236 | if (spi_write(host->spi, &nullbyte, 1) < 0) |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1237 | dev_dbg(&host->spi->dev, |
| 1238 | "put spi signals to low failed\n"); |
| 1239 | |
| 1240 | /* |
| 1241 | * Now clock should be low due to spi mode 0; |
| 1242 | * MOSI should be low because of written 0x00; |
| 1243 | * chipselect should be low (it is active low) |
| 1244 | * power supply is off, so now MMC is off too! |
| 1245 | * |
| 1246 | * FIXME no, chipselect can be high since the |
| 1247 | * device is inactive and SPI_CS_HIGH is clear... |
| 1248 | */ |
| 1249 | msleep(10); |
| 1250 | if (mres == 0) { |
| 1251 | host->spi->mode |= (SPI_CPOL|SPI_CPHA); |
| 1252 | mres = spi_setup(host->spi); |
| 1253 | if (mres < 0) |
| 1254 | dev_dbg(&host->spi->dev, |
| 1255 | "switch back to SPI mode 3" |
| 1256 | " failed\n"); |
| 1257 | } |
| 1258 | } |
| 1259 | |
| 1260 | host->power_mode = ios->power_mode; |
| 1261 | } |
| 1262 | |
| 1263 | if (host->spi->max_speed_hz != ios->clock && ios->clock != 0) { |
| 1264 | int status; |
| 1265 | |
| 1266 | host->spi->max_speed_hz = ios->clock; |
| 1267 | status = spi_setup(host->spi); |
| 1268 | dev_dbg(&host->spi->dev, |
| 1269 | "mmc_spi: clock to %d Hz, %d\n", |
| 1270 | host->spi->max_speed_hz, status); |
| 1271 | } |
| 1272 | } |
| 1273 | |
| 1274 | static int mmc_spi_get_ro(struct mmc_host *mmc) |
| 1275 | { |
| 1276 | struct mmc_spi_host *host = mmc_priv(mmc); |
| 1277 | |
| 1278 | if (host->pdata && host->pdata->get_ro) |
Anton Vorontsov | 08f80bb | 2008-06-17 18:17:39 +0400 | [diff] [blame] | 1279 | return !!host->pdata->get_ro(mmc->parent); |
| 1280 | /* |
| 1281 | * Board doesn't support read only detection; let the mmc core |
| 1282 | * decide what to do. |
| 1283 | */ |
| 1284 | return -ENOSYS; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1285 | } |
| 1286 | |
Anton Vorontsov | 619ef4b | 2008-06-17 18:17:21 +0400 | [diff] [blame] | 1287 | static int mmc_spi_get_cd(struct mmc_host *mmc) |
| 1288 | { |
| 1289 | struct mmc_spi_host *host = mmc_priv(mmc); |
| 1290 | |
| 1291 | if (host->pdata && host->pdata->get_cd) |
| 1292 | return !!host->pdata->get_cd(mmc->parent); |
| 1293 | return -ENOSYS; |
| 1294 | } |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1295 | |
| 1296 | static const struct mmc_host_ops mmc_spi_ops = { |
| 1297 | .request = mmc_spi_request, |
| 1298 | .set_ios = mmc_spi_set_ios, |
| 1299 | .get_ro = mmc_spi_get_ro, |
Anton Vorontsov | 619ef4b | 2008-06-17 18:17:21 +0400 | [diff] [blame] | 1300 | .get_cd = mmc_spi_get_cd, |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1301 | }; |
| 1302 | |
| 1303 | |
| 1304 | /****************************************************************************/ |
| 1305 | |
| 1306 | /* |
| 1307 | * SPI driver implementation |
| 1308 | */ |
| 1309 | |
| 1310 | static irqreturn_t |
| 1311 | mmc_spi_detect_irq(int irq, void *mmc) |
| 1312 | { |
| 1313 | struct mmc_spi_host *host = mmc_priv(mmc); |
| 1314 | u16 delay_msec = max(host->pdata->detect_delay, (u16)100); |
| 1315 | |
| 1316 | mmc_detect_change(mmc, msecs_to_jiffies(delay_msec)); |
| 1317 | return IRQ_HANDLED; |
| 1318 | } |
| 1319 | |
| 1320 | static int mmc_spi_probe(struct spi_device *spi) |
| 1321 | { |
| 1322 | void *ones; |
| 1323 | struct mmc_host *mmc; |
| 1324 | struct mmc_spi_host *host; |
| 1325 | int status; |
| 1326 | |
David Brownell | 70d6027 | 2009-06-30 11:41:27 -0700 | [diff] [blame] | 1327 | /* We rely on full duplex transfers, mostly to reduce |
| 1328 | * per-transfer overheads (by making fewer transfers). |
| 1329 | */ |
| 1330 | if (spi->master->flags & SPI_MASTER_HALF_DUPLEX) |
| 1331 | return -EINVAL; |
| 1332 | |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1333 | /* MMC and SD specs only seem to care that sampling is on the |
| 1334 | * rising edge ... meaning SPI modes 0 or 3. So either SPI mode |
Wolfgang Muees | 48881ca | 2009-03-11 14:13:15 +0100 | [diff] [blame] | 1335 | * should be legit. We'll use mode 0 since the steady state is 0, |
| 1336 | * which is appropriate for hotplugging, unless the platform data |
| 1337 | * specify mode 3 (if hardware is not compatible to mode 0). |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1338 | */ |
Wolfgang Muees | 48881ca | 2009-03-11 14:13:15 +0100 | [diff] [blame] | 1339 | if (spi->mode != SPI_MODE_3) |
| 1340 | spi->mode = SPI_MODE_0; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1341 | spi->bits_per_word = 8; |
| 1342 | |
| 1343 | status = spi_setup(spi); |
| 1344 | if (status < 0) { |
| 1345 | dev_dbg(&spi->dev, "needs SPI mode %02x, %d KHz; %d\n", |
| 1346 | spi->mode, spi->max_speed_hz / 1000, |
| 1347 | status); |
| 1348 | return status; |
| 1349 | } |
| 1350 | |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1351 | /* We need a supply of ones to transmit. This is the only time |
| 1352 | * the CPU touches these, so cache coherency isn't a concern. |
| 1353 | * |
| 1354 | * NOTE if many systems use more than one MMC-over-SPI connector |
| 1355 | * it'd save some memory to share this. That's evidently rare. |
| 1356 | */ |
| 1357 | status = -ENOMEM; |
| 1358 | ones = kmalloc(MMC_SPI_BLOCKSIZE, GFP_KERNEL); |
| 1359 | if (!ones) |
| 1360 | goto nomem; |
| 1361 | memset(ones, 0xff, MMC_SPI_BLOCKSIZE); |
| 1362 | |
| 1363 | mmc = mmc_alloc_host(sizeof(*host), &spi->dev); |
| 1364 | if (!mmc) |
| 1365 | goto nomem; |
| 1366 | |
| 1367 | mmc->ops = &mmc_spi_ops; |
| 1368 | mmc->max_blk_size = MMC_SPI_BLOCKSIZE; |
Martin K. Petersen | a36274e | 2010-09-10 01:33:59 -0400 | [diff] [blame] | 1369 | mmc->max_segs = MMC_SPI_BLOCKSATONCE; |
Wolfgang Muees | 5cf20aa | 2009-04-08 10:14:07 +0100 | [diff] [blame] | 1370 | mmc->max_req_size = MMC_SPI_BLOCKSATONCE * MMC_SPI_BLOCKSIZE; |
| 1371 | mmc->max_blk_count = MMC_SPI_BLOCKSATONCE; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1372 | |
Pierre Ossman | 23af603 | 2008-07-06 01:10:27 +0200 | [diff] [blame] | 1373 | mmc->caps = MMC_CAP_SPI; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1374 | |
| 1375 | /* SPI doesn't need the lowspeed device identification thing for |
| 1376 | * MMC or SD cards, since it never comes up in open drain mode. |
| 1377 | * That's good; some SPI masters can't handle very low speeds! |
| 1378 | * |
| 1379 | * However, low speed SDIO cards need not handle over 400 KHz; |
| 1380 | * that's the only reason not to use a few MHz for f_min (until |
| 1381 | * the upper layer reads the target frequency from the CSD). |
| 1382 | */ |
| 1383 | mmc->f_min = 400000; |
| 1384 | mmc->f_max = spi->max_speed_hz; |
| 1385 | |
| 1386 | host = mmc_priv(mmc); |
| 1387 | host->mmc = mmc; |
| 1388 | host->spi = spi; |
| 1389 | |
| 1390 | host->ones = ones; |
| 1391 | |
| 1392 | /* Platform data is used to hook up things like card sensing |
| 1393 | * and power switching gpios. |
| 1394 | */ |
Anton Vorontsov | 9c43df5 | 2008-12-30 18:15:28 +0300 | [diff] [blame] | 1395 | host->pdata = mmc_spi_get_pdata(spi); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1396 | if (host->pdata) |
| 1397 | mmc->ocr_avail = host->pdata->ocr_mask; |
| 1398 | if (!mmc->ocr_avail) { |
| 1399 | dev_warn(&spi->dev, "ASSUMING 3.2-3.4 V slot power\n"); |
| 1400 | mmc->ocr_avail = MMC_VDD_32_33|MMC_VDD_33_34; |
| 1401 | } |
| 1402 | if (host->pdata && host->pdata->setpower) { |
| 1403 | host->powerup_msecs = host->pdata->powerup_msecs; |
| 1404 | if (!host->powerup_msecs || host->powerup_msecs > 250) |
| 1405 | host->powerup_msecs = 250; |
| 1406 | } |
| 1407 | |
| 1408 | dev_set_drvdata(&spi->dev, mmc); |
| 1409 | |
| 1410 | /* preallocate dma buffers */ |
| 1411 | host->data = kmalloc(sizeof(*host->data), GFP_KERNEL); |
| 1412 | if (!host->data) |
| 1413 | goto fail_nobuf1; |
| 1414 | |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1415 | if (spi->master->dev.parent->dma_mask) { |
| 1416 | struct device *dev = spi->master->dev.parent; |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1417 | |
| 1418 | host->dma_dev = dev; |
| 1419 | host->ones_dma = dma_map_single(dev, ones, |
| 1420 | MMC_SPI_BLOCKSIZE, DMA_TO_DEVICE); |
| 1421 | host->data_dma = dma_map_single(dev, host->data, |
| 1422 | sizeof(*host->data), DMA_BIDIRECTIONAL); |
| 1423 | |
| 1424 | /* REVISIT in theory those map operations can fail... */ |
| 1425 | |
| 1426 | dma_sync_single_for_cpu(host->dma_dev, |
| 1427 | host->data_dma, sizeof(*host->data), |
| 1428 | DMA_BIDIRECTIONAL); |
| 1429 | } |
| 1430 | |
| 1431 | /* setup message for status/busy readback */ |
| 1432 | spi_message_init(&host->readback); |
| 1433 | host->readback.is_dma_mapped = (host->dma_dev != NULL); |
| 1434 | |
| 1435 | spi_message_add_tail(&host->status, &host->readback); |
| 1436 | host->status.tx_buf = host->ones; |
| 1437 | host->status.tx_dma = host->ones_dma; |
| 1438 | host->status.rx_buf = &host->data->status; |
| 1439 | host->status.rx_dma = host->data_dma + offsetof(struct scratch, status); |
| 1440 | host->status.cs_change = 1; |
| 1441 | |
| 1442 | /* register card detect irq */ |
| 1443 | if (host->pdata && host->pdata->init) { |
| 1444 | status = host->pdata->init(&spi->dev, mmc_spi_detect_irq, mmc); |
| 1445 | if (status != 0) |
| 1446 | goto fail_glue_init; |
| 1447 | } |
| 1448 | |
Anton Vorontsov | 619ef4b | 2008-06-17 18:17:21 +0400 | [diff] [blame] | 1449 | /* pass platform capabilities, if any */ |
| 1450 | if (host->pdata) |
| 1451 | mmc->caps |= host->pdata->caps; |
| 1452 | |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1453 | status = mmc_add_host(mmc); |
| 1454 | if (status != 0) |
| 1455 | goto fail_add_host; |
| 1456 | |
Anton Vorontsov | 619ef4b | 2008-06-17 18:17:21 +0400 | [diff] [blame] | 1457 | dev_info(&spi->dev, "SD/MMC host %s%s%s%s%s\n", |
Kay Sievers | d1b2686 | 2008-11-08 21:37:46 +0100 | [diff] [blame] | 1458 | dev_name(&mmc->class_dev), |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1459 | host->dma_dev ? "" : ", no DMA", |
| 1460 | (host->pdata && host->pdata->get_ro) |
| 1461 | ? "" : ", no WP", |
| 1462 | (host->pdata && host->pdata->setpower) |
Anton Vorontsov | 619ef4b | 2008-06-17 18:17:21 +0400 | [diff] [blame] | 1463 | ? "" : ", no poweroff", |
| 1464 | (mmc->caps & MMC_CAP_NEEDS_POLL) |
| 1465 | ? ", cd polling" : ""); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1466 | return 0; |
| 1467 | |
| 1468 | fail_add_host: |
| 1469 | mmc_remove_host (mmc); |
| 1470 | fail_glue_init: |
| 1471 | if (host->dma_dev) |
| 1472 | dma_unmap_single(host->dma_dev, host->data_dma, |
| 1473 | sizeof(*host->data), DMA_BIDIRECTIONAL); |
| 1474 | kfree(host->data); |
| 1475 | |
| 1476 | fail_nobuf1: |
| 1477 | mmc_free_host(mmc); |
Anton Vorontsov | 9c43df5 | 2008-12-30 18:15:28 +0300 | [diff] [blame] | 1478 | mmc_spi_put_pdata(spi); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1479 | dev_set_drvdata(&spi->dev, NULL); |
| 1480 | |
| 1481 | nomem: |
| 1482 | kfree(ones); |
| 1483 | return status; |
| 1484 | } |
| 1485 | |
| 1486 | |
| 1487 | static int __devexit mmc_spi_remove(struct spi_device *spi) |
| 1488 | { |
| 1489 | struct mmc_host *mmc = dev_get_drvdata(&spi->dev); |
| 1490 | struct mmc_spi_host *host; |
| 1491 | |
| 1492 | if (mmc) { |
| 1493 | host = mmc_priv(mmc); |
| 1494 | |
| 1495 | /* prevent new mmc_detect_change() calls */ |
| 1496 | if (host->pdata && host->pdata->exit) |
| 1497 | host->pdata->exit(&spi->dev, mmc); |
| 1498 | |
| 1499 | mmc_remove_host(mmc); |
| 1500 | |
| 1501 | if (host->dma_dev) { |
| 1502 | dma_unmap_single(host->dma_dev, host->ones_dma, |
| 1503 | MMC_SPI_BLOCKSIZE, DMA_TO_DEVICE); |
| 1504 | dma_unmap_single(host->dma_dev, host->data_dma, |
| 1505 | sizeof(*host->data), DMA_BIDIRECTIONAL); |
| 1506 | } |
| 1507 | |
| 1508 | kfree(host->data); |
| 1509 | kfree(host->ones); |
| 1510 | |
| 1511 | spi->max_speed_hz = mmc->f_max; |
| 1512 | mmc_free_host(mmc); |
Anton Vorontsov | 9c43df5 | 2008-12-30 18:15:28 +0300 | [diff] [blame] | 1513 | mmc_spi_put_pdata(spi); |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1514 | dev_set_drvdata(&spi->dev, NULL); |
| 1515 | } |
| 1516 | return 0; |
| 1517 | } |
| 1518 | |
Grant Likely | 2ffe8c5 | 2010-06-08 07:48:19 -0600 | [diff] [blame] | 1519 | #if defined(CONFIG_OF) |
| 1520 | static struct of_device_id mmc_spi_of_match_table[] __devinitdata = { |
| 1521 | { .compatible = "mmc-spi-slot", }, |
Anton Vorontsov | fbe0f83 | 2010-08-08 18:14:22 +0400 | [diff] [blame] | 1522 | {}, |
Grant Likely | 2ffe8c5 | 2010-06-08 07:48:19 -0600 | [diff] [blame] | 1523 | }; |
| 1524 | #endif |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1525 | |
| 1526 | static struct spi_driver mmc_spi_driver = { |
| 1527 | .driver = { |
| 1528 | .name = "mmc_spi", |
| 1529 | .bus = &spi_bus_type, |
| 1530 | .owner = THIS_MODULE, |
Grant Likely | 2ffe8c5 | 2010-06-08 07:48:19 -0600 | [diff] [blame] | 1531 | #if defined(CONFIG_OF) |
| 1532 | .of_match_table = mmc_spi_of_match_table, |
| 1533 | #endif |
David Brownell | 15a0580 | 2007-08-08 09:12:54 -0700 | [diff] [blame] | 1534 | }, |
| 1535 | .probe = mmc_spi_probe, |
| 1536 | .remove = __devexit_p(mmc_spi_remove), |
| 1537 | }; |
| 1538 | |
| 1539 | |
| 1540 | static int __init mmc_spi_init(void) |
| 1541 | { |
| 1542 | return spi_register_driver(&mmc_spi_driver); |
| 1543 | } |
| 1544 | module_init(mmc_spi_init); |
| 1545 | |
| 1546 | |
| 1547 | static void __exit mmc_spi_exit(void) |
| 1548 | { |
| 1549 | spi_unregister_driver(&mmc_spi_driver); |
| 1550 | } |
| 1551 | module_exit(mmc_spi_exit); |
| 1552 | |
| 1553 | |
| 1554 | MODULE_AUTHOR("Mike Lavender, David Brownell, " |
| 1555 | "Hans-Peter Nilsson, Jan Nikitenko"); |
| 1556 | MODULE_DESCRIPTION("SPI SD/MMC host driver"); |
| 1557 | MODULE_LICENSE("GPL"); |
Anton Vorontsov | e0626e3 | 2009-09-22 16:46:08 -0700 | [diff] [blame] | 1558 | MODULE_ALIAS("spi:mmc_spi"); |