diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/spi/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/spi/Makefile | 1 | ||||
| -rw-r--r-- | drivers/spi/atmel_spi.c | 678 | ||||
| -rw-r--r-- | drivers/spi/atmel_spi.h | 167 |
4 files changed, 853 insertions, 0 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 9052f4c3493b..7e54e48efd5c 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig | |||
| @@ -51,6 +51,13 @@ config SPI_MASTER | |||
| 51 | comment "SPI Master Controller Drivers" | 51 | comment "SPI Master Controller Drivers" |
| 52 | depends on SPI_MASTER | 52 | depends on SPI_MASTER |
| 53 | 53 | ||
| 54 | config SPI_ATMEL | ||
| 55 | tristate "Atmel SPI Controller" | ||
| 56 | depends on (ARCH_AT91 || AVR32) && SPI_MASTER | ||
| 57 | help | ||
| 58 | This selects a driver for the Atmel SPI Controller, present on | ||
| 59 | many AT32 (AVR32) and AT91 (ARM) chips. | ||
| 60 | |||
| 54 | config SPI_BITBANG | 61 | config SPI_BITBANG |
| 55 | tristate "Bitbanging SPI master" | 62 | tristate "Bitbanging SPI master" |
| 56 | depends on SPI_MASTER && EXPERIMENTAL | 63 | depends on SPI_MASTER && EXPERIMENTAL |
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index bf271fe4e536..3c280ad89202 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile | |||
| @@ -12,6 +12,7 @@ obj-$(CONFIG_SPI_MASTER) += spi.o | |||
| 12 | 12 | ||
| 13 | # SPI master controller drivers (bus) | 13 | # SPI master controller drivers (bus) |
| 14 | obj-$(CONFIG_SPI_BITBANG) += spi_bitbang.o | 14 | obj-$(CONFIG_SPI_BITBANG) += spi_bitbang.o |
| 15 | obj-$(CONFIG_SPI_ATMEL) += atmel_spi.o | ||
| 15 | obj-$(CONFIG_SPI_BUTTERFLY) += spi_butterfly.o | 16 | obj-$(CONFIG_SPI_BUTTERFLY) += spi_butterfly.o |
| 16 | obj-$(CONFIG_SPI_IMX) += spi_imx.o | 17 | obj-$(CONFIG_SPI_IMX) += spi_imx.o |
| 17 | obj-$(CONFIG_SPI_PXA2XX) += pxa2xx_spi.o | 18 | obj-$(CONFIG_SPI_PXA2XX) += pxa2xx_spi.o |
diff --git a/drivers/spi/atmel_spi.c b/drivers/spi/atmel_spi.c new file mode 100644 index 000000000000..c2a9fef58edc --- /dev/null +++ b/drivers/spi/atmel_spi.c | |||
| @@ -0,0 +1,678 @@ | |||
| 1 | /* | ||
| 2 | * Driver for Atmel AT32 and AT91 SPI Controllers | ||
| 3 | * | ||
| 4 | * Copyright (C) 2006 Atmel Corporation | ||
| 5 | * | ||
| 6 | * This program is free software; you can redistribute it and/or modify | ||
| 7 | * it under the terms of the GNU General Public License version 2 as | ||
| 8 | * published by the Free Software Foundation. | ||
| 9 | */ | ||
| 10 | |||
| 11 | #include <linux/kernel.h> | ||
| 12 | #include <linux/init.h> | ||
| 13 | #include <linux/clk.h> | ||
| 14 | #include <linux/module.h> | ||
| 15 | #include <linux/platform_device.h> | ||
| 16 | #include <linux/delay.h> | ||
| 17 | #include <linux/dma-mapping.h> | ||
| 18 | #include <linux/err.h> | ||
| 19 | #include <linux/interrupt.h> | ||
| 20 | #include <linux/spi/spi.h> | ||
| 21 | |||
| 22 | #include <asm/io.h> | ||
| 23 | #include <asm/arch/board.h> | ||
| 24 | #include <asm/arch/gpio.h> | ||
| 25 | |||
| 26 | #include "atmel_spi.h" | ||
| 27 | |||
| 28 | /* | ||
| 29 | * The core SPI transfer engine just talks to a register bank to set up | ||
| 30 | * DMA transfers; transfer queue progress is driven by IRQs. The clock | ||
| 31 | * framework provides the base clock, subdivided for each spi_device. | ||
| 32 | * | ||
| 33 | * Newer controllers, marked with "new_1" flag, have: | ||
| 34 | * - CR.LASTXFER | ||
| 35 | * - SPI_MR.DIV32 may become FDIV or must-be-zero (here: always zero) | ||
| 36 | * - SPI_SR.TXEMPTY, SPI_SR.NSSR (and corresponding irqs) | ||
| 37 | * - SPI_CSRx.CSAAT | ||
| 38 | * - SPI_CSRx.SBCR allows faster clocking | ||
| 39 | */ | ||
| 40 | struct atmel_spi { | ||
| 41 | spinlock_t lock; | ||
| 42 | |||
| 43 | void __iomem *regs; | ||
| 44 | int irq; | ||
| 45 | struct clk *clk; | ||
| 46 | struct platform_device *pdev; | ||
| 47 | unsigned new_1:1; | ||
| 48 | |||
| 49 | u8 stopping; | ||
| 50 | struct list_head queue; | ||
| 51 | struct spi_transfer *current_transfer; | ||
| 52 | unsigned long remaining_bytes; | ||
| 53 | |||
| 54 | void *buffer; | ||
| 55 | dma_addr_t buffer_dma; | ||
| 56 | }; | ||
| 57 | |||
| 58 | #define BUFFER_SIZE PAGE_SIZE | ||
| 59 | #define INVALID_DMA_ADDRESS 0xffffffff | ||
| 60 | |||
| 61 | /* | ||
| 62 | * Earlier SPI controllers (e.g. on at91rm9200) have a design bug whereby | ||
| 63 | * they assume that spi slave device state will not change on deselect, so | ||
| 64 | * that automagic deselection is OK. Not so! Workaround uses nCSx pins | ||
| 65 | * as GPIOs; or newer controllers have CSAAT and friends. | ||
| 66 | * | ||
| 67 | * Since the CSAAT functionality is a bit weird on newer controllers | ||
| 68 | * as well, we use GPIO to control nCSx pins on all controllers. | ||
| 69 | */ | ||
| 70 | |||
| 71 | static inline void cs_activate(struct spi_device *spi) | ||
| 72 | { | ||
| 73 | unsigned gpio = (unsigned) spi->controller_data; | ||
| 74 | unsigned active = spi->mode & SPI_CS_HIGH; | ||
| 75 | |||
| 76 | dev_dbg(&spi->dev, "activate %u%s\n", gpio, active ? " (high)" : ""); | ||
| 77 | gpio_set_value(gpio, active); | ||
| 78 | } | ||
| 79 | |||
| 80 | static inline void cs_deactivate(struct spi_device *spi) | ||
| 81 | { | ||
| 82 | unsigned gpio = (unsigned) spi->controller_data; | ||
| 83 | unsigned active = spi->mode & SPI_CS_HIGH; | ||
| 84 | |||
| 85 | dev_dbg(&spi->dev, "DEactivate %u%s\n", gpio, active ? " (low)" : ""); | ||
| 86 | gpio_set_value(gpio, !active); | ||
| 87 | } | ||
| 88 | |||
| 89 | /* | ||
| 90 | * Submit next transfer for DMA. | ||
| 91 | * lock is held, spi irq is blocked | ||
| 92 | */ | ||
| 93 | static void atmel_spi_next_xfer(struct spi_master *master, | ||
| 94 | struct spi_message *msg) | ||
| 95 | { | ||
| 96 | struct atmel_spi *as = spi_master_get_devdata(master); | ||
| 97 | struct spi_transfer *xfer; | ||
| 98 | u32 len; | ||
| 99 | dma_addr_t tx_dma, rx_dma; | ||
| 100 | |||
| 101 | xfer = as->current_transfer; | ||
| 102 | if (!xfer || as->remaining_bytes == 0) { | ||
| 103 | if (xfer) | ||
| 104 | xfer = list_entry(xfer->transfer_list.next, | ||
| 105 | struct spi_transfer, transfer_list); | ||
| 106 | else | ||
| 107 | xfer = list_entry(msg->transfers.next, | ||
| 108 | struct spi_transfer, transfer_list); | ||
| 109 | as->remaining_bytes = xfer->len; | ||
| 110 | as->current_transfer = xfer; | ||
| 111 | } | ||
| 112 | |||
| 113 | len = as->remaining_bytes; | ||
| 114 | |||
| 115 | tx_dma = xfer->tx_dma; | ||
| 116 | rx_dma = xfer->rx_dma; | ||
| 117 | |||
| 118 | /* use scratch buffer only when rx or tx data is unspecified */ | ||
| 119 | if (rx_dma == INVALID_DMA_ADDRESS) { | ||
| 120 | rx_dma = as->buffer_dma; | ||
| 121 | if (len > BUFFER_SIZE) | ||
| 122 | len = BUFFER_SIZE; | ||
| 123 | } | ||
| 124 | if (tx_dma == INVALID_DMA_ADDRESS) { | ||
| 125 | tx_dma = as->buffer_dma; | ||
| 126 | if (len > BUFFER_SIZE) | ||
| 127 | len = BUFFER_SIZE; | ||
| 128 | memset(as->buffer, 0, len); | ||
| 129 | dma_sync_single_for_device(&as->pdev->dev, | ||
| 130 | as->buffer_dma, len, DMA_TO_DEVICE); | ||
| 131 | } | ||
| 132 | |||
| 133 | spi_writel(as, RPR, rx_dma); | ||
| 134 | spi_writel(as, TPR, tx_dma); | ||
| 135 | |||
| 136 | as->remaining_bytes -= len; | ||
| 137 | if (msg->spi->bits_per_word > 8) | ||
| 138 | len >>= 1; | ||
| 139 | |||
| 140 | /* REVISIT: when xfer->delay_usecs == 0, the PDC "next transfer" | ||
| 141 | * mechanism might help avoid the IRQ latency between transfers | ||
| 142 | * | ||
| 143 | * We're also waiting for ENDRX before we start the next | ||
| 144 | * transfer because we need to handle some difficult timing | ||
| 145 | * issues otherwise. If we wait for ENDTX in one transfer and | ||
| 146 | * then starts waiting for ENDRX in the next, it's difficult | ||
| 147 | * to tell the difference between the ENDRX interrupt we're | ||
| 148 | * actually waiting for and the ENDRX interrupt of the | ||
| 149 | * previous transfer. | ||
| 150 | * | ||
| 151 | * It should be doable, though. Just not now... | ||
| 152 | */ | ||
| 153 | spi_writel(as, TNCR, 0); | ||
| 154 | spi_writel(as, RNCR, 0); | ||
| 155 | spi_writel(as, IER, SPI_BIT(ENDRX) | SPI_BIT(OVRES)); | ||
| 156 | |||
| 157 | dev_dbg(&msg->spi->dev, | ||
| 158 | " start xfer %p: len %u tx %p/%08x rx %p/%08x imr %03x\n", | ||
| 159 | xfer, xfer->len, xfer->tx_buf, xfer->tx_dma, | ||
| 160 | xfer->rx_buf, xfer->rx_dma, spi_readl(as, IMR)); | ||
| 161 | |||
| 162 | spi_writel(as, TCR, len); | ||
| 163 | spi_writel(as, RCR, len); | ||
| 164 | spi_writel(as, PTCR, SPI_BIT(TXTEN) | SPI_BIT(RXTEN)); | ||
| 165 | } | ||
| 166 | |||
| 167 | static void atmel_spi_next_message(struct spi_master *master) | ||
| 168 | { | ||
| 169 | struct atmel_spi *as = spi_master_get_devdata(master); | ||
| 170 | struct spi_message *msg; | ||
| 171 | u32 mr; | ||
| 172 | |||
| 173 | BUG_ON(as->current_transfer); | ||
| 174 | |||
| 175 | msg = list_entry(as->queue.next, struct spi_message, queue); | ||
| 176 | |||
| 177 | /* Select the chip */ | ||
| 178 | mr = spi_readl(as, MR); | ||
| 179 | mr = SPI_BFINS(PCS, ~(1 << msg->spi->chip_select), mr); | ||
| 180 | spi_writel(as, MR, mr); | ||
| 181 | cs_activate(msg->spi); | ||
| 182 | |||
| 183 | atmel_spi_next_xfer(master, msg); | ||
| 184 | } | ||
| 185 | |||
| 186 | static void | ||
| 187 | atmel_spi_dma_map_xfer(struct atmel_spi *as, struct spi_transfer *xfer) | ||
| 188 | { | ||
| 189 | xfer->tx_dma = xfer->rx_dma = INVALID_DMA_ADDRESS; | ||
| 190 | if (xfer->tx_buf) | ||
| 191 | xfer->tx_dma = dma_map_single(&as->pdev->dev, | ||
| 192 | (void *) xfer->tx_buf, xfer->len, | ||
| 193 | DMA_TO_DEVICE); | ||
| 194 | if (xfer->rx_buf) | ||
| 195 | xfer->rx_dma = dma_map_single(&as->pdev->dev, | ||
| 196 | xfer->rx_buf, xfer->len, | ||
| 197 | DMA_FROM_DEVICE); | ||
| 198 | } | ||
| 199 | |||
| 200 | static void atmel_spi_dma_unmap_xfer(struct spi_master *master, | ||
| 201 | struct spi_transfer *xfer) | ||
| 202 | { | ||
| 203 | if (xfer->tx_dma != INVALID_DMA_ADDRESS) | ||
| 204 | dma_unmap_single(master->cdev.dev, xfer->tx_dma, | ||
| 205 | xfer->len, DMA_TO_DEVICE); | ||
| 206 | if (xfer->rx_dma != INVALID_DMA_ADDRESS) | ||
| 207 | dma_unmap_single(master->cdev.dev, xfer->rx_dma, | ||
| 208 | xfer->len, DMA_FROM_DEVICE); | ||
| 209 | } | ||
| 210 | |||
| 211 | static void | ||
| 212 | atmel_spi_msg_done(struct spi_master *master, struct atmel_spi *as, | ||
| 213 | struct spi_message *msg, int status) | ||
| 214 | { | ||
| 215 | cs_deactivate(msg->spi); | ||
| 216 | list_del(&msg->queue); | ||
| 217 | msg->status = status; | ||
| 218 | |||
| 219 | dev_dbg(master->cdev.dev, | ||
| 220 | "xfer complete: %u bytes transferred\n", | ||
| 221 | msg->actual_length); | ||
| 222 | |||
| 223 | spin_unlock(&as->lock); | ||
| 224 | msg->complete(msg->context); | ||
| 225 | spin_lock(&as->lock); | ||
| 226 | |||
| 227 | as->current_transfer = NULL; | ||
| 228 | |||
| 229 | /* continue if needed */ | ||
| 230 | if (list_empty(&as->queue) || as->stopping) | ||
| 231 | spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); | ||
| 232 | else | ||
| 233 | atmel_spi_next_message(master); | ||
| 234 | } | ||
| 235 | |||
| 236 | static irqreturn_t | ||
| 237 | atmel_spi_interrupt(int irq, void *dev_id) | ||
| 238 | { | ||
| 239 | struct spi_master *master = dev_id; | ||
| 240 | struct atmel_spi *as = spi_master_get_devdata(master); | ||
| 241 | struct spi_message *msg; | ||
| 242 | struct spi_transfer *xfer; | ||
| 243 | u32 status, pending, imr; | ||
| 244 | int ret = IRQ_NONE; | ||
| 245 | |||
| 246 | spin_lock(&as->lock); | ||
| 247 | |||
| 248 | xfer = as->current_transfer; | ||
| 249 | msg = list_entry(as->queue.next, struct spi_message, queue); | ||
| 250 | |||
| 251 | imr = spi_readl(as, IMR); | ||
| 252 | status = spi_readl(as, SR); | ||
| 253 | pending = status & imr; | ||
| 254 | |||
| 255 | if (pending & SPI_BIT(OVRES)) { | ||
| 256 | int timeout; | ||
| 257 | |||
| 258 | ret = IRQ_HANDLED; | ||
| 259 | |||
| 260 | spi_writel(as, IDR, (SPI_BIT(ENDTX) | SPI_BIT(ENDRX) | ||
| 261 | | SPI_BIT(OVRES))); | ||
| 262 | |||
| 263 | /* | ||
| 264 | * When we get an overrun, we disregard the current | ||
| 265 | * transfer. Data will not be copied back from any | ||
| 266 | * bounce buffer and msg->actual_len will not be | ||
| 267 | * updated with the last xfer. | ||
| 268 | * | ||
| 269 | * We will also not process any remaning transfers in | ||
| 270 | * the message. | ||
| 271 | * | ||
| 272 | * First, stop the transfer and unmap the DMA buffers. | ||
| 273 | */ | ||
| 274 | spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); | ||
| 275 | if (!msg->is_dma_mapped) | ||
| 276 | atmel_spi_dma_unmap_xfer(master, xfer); | ||
| 277 | |||
| 278 | /* REVISIT: udelay in irq is unfriendly */ | ||
| 279 | if (xfer->delay_usecs) | ||
| 280 | udelay(xfer->delay_usecs); | ||
| 281 | |||
| 282 | dev_warn(master->cdev.dev, "fifo overrun (%u/%u remaining)\n", | ||
| 283 | spi_readl(as, TCR), spi_readl(as, RCR)); | ||
| 284 | |||
| 285 | /* | ||
| 286 | * Clean up DMA registers and make sure the data | ||
| 287 | * registers are empty. | ||
| 288 | */ | ||
| 289 | spi_writel(as, RNCR, 0); | ||
| 290 | spi_writel(as, TNCR, 0); | ||
| 291 | spi_writel(as, RCR, 0); | ||
| 292 | spi_writel(as, TCR, 0); | ||
| 293 | for (timeout = 1000; timeout; timeout--) | ||
| 294 | if (spi_readl(as, SR) & SPI_BIT(TXEMPTY)) | ||
| 295 | break; | ||
| 296 | if (!timeout) | ||
| 297 | dev_warn(master->cdev.dev, | ||
| 298 | "timeout waiting for TXEMPTY"); | ||
| 299 | while (spi_readl(as, SR) & SPI_BIT(RDRF)) | ||
| 300 | spi_readl(as, RDR); | ||
| 301 | |||
| 302 | /* Clear any overrun happening while cleaning up */ | ||
| 303 | spi_readl(as, SR); | ||
| 304 | |||
| 305 | atmel_spi_msg_done(master, as, msg, -EIO); | ||
| 306 | } else if (pending & SPI_BIT(ENDRX)) { | ||
| 307 | ret = IRQ_HANDLED; | ||
| 308 | |||
| 309 | spi_writel(as, IDR, pending); | ||
| 310 | |||
| 311 | if (as->remaining_bytes == 0) { | ||
| 312 | msg->actual_length += xfer->len; | ||
| 313 | |||
| 314 | if (!msg->is_dma_mapped) | ||
| 315 | atmel_spi_dma_unmap_xfer(master, xfer); | ||
| 316 | |||
| 317 | /* REVISIT: udelay in irq is unfriendly */ | ||
| 318 | if (xfer->delay_usecs) | ||
| 319 | udelay(xfer->delay_usecs); | ||
| 320 | |||
| 321 | if (msg->transfers.prev == &xfer->transfer_list) { | ||
| 322 | /* report completed message */ | ||
| 323 | atmel_spi_msg_done(master, as, msg, 0); | ||
| 324 | } else { | ||
| 325 | if (xfer->cs_change) { | ||
| 326 | cs_deactivate(msg->spi); | ||
| 327 | udelay(1); | ||
| 328 | cs_activate(msg->spi); | ||
| 329 | } | ||
| 330 | |||
| 331 | /* | ||
| 332 | * Not done yet. Submit the next transfer. | ||
| 333 | * | ||
| 334 | * FIXME handle protocol options for xfer | ||
| 335 | */ | ||
| 336 | atmel_spi_next_xfer(master, msg); | ||
| 337 | } | ||
| 338 | } else { | ||
| 339 | /* | ||
| 340 | * Keep going, we still have data to send in | ||
| 341 | * the current transfer. | ||
| 342 | */ | ||
| 343 | atmel_spi_next_xfer(master, msg); | ||
| 344 | } | ||
| 345 | } | ||
| 346 | |||
| 347 | spin_unlock(&as->lock); | ||
| 348 | |||
| 349 | return ret; | ||
| 350 | } | ||
| 351 | |||
| 352 | #define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH) | ||
| 353 | |||
| 354 | static int atmel_spi_setup(struct spi_device *spi) | ||
| 355 | { | ||
| 356 | struct atmel_spi *as; | ||
| 357 | u32 scbr, csr; | ||
| 358 | unsigned int bits = spi->bits_per_word; | ||
| 359 | unsigned long bus_hz, sck_hz; | ||
| 360 | unsigned int npcs_pin; | ||
| 361 | int ret; | ||
| 362 | |||
| 363 | as = spi_master_get_devdata(spi->master); | ||
| 364 | |||
| 365 | if (as->stopping) | ||
| 366 | return -ESHUTDOWN; | ||
| 367 | |||
| 368 | if (spi->chip_select > spi->master->num_chipselect) { | ||
| 369 | dev_dbg(&spi->dev, | ||
| 370 | "setup: invalid chipselect %u (%u defined)\n", | ||
| 371 | spi->chip_select, spi->master->num_chipselect); | ||
| 372 | return -EINVAL; | ||
| 373 | } | ||
| 374 | |||
| 375 | if (bits == 0) | ||
| 376 | bits = 8; | ||
| 377 | if (bits < 8 || bits > 16) { | ||
| 378 | dev_dbg(&spi->dev, | ||
| 379 | "setup: invalid bits_per_word %u (8 to 16)\n", | ||
| 380 | bits); | ||
| 381 | return -EINVAL; | ||
| 382 | } | ||
| 383 | |||
| 384 | if (spi->mode & ~MODEBITS) { | ||
| 385 | dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n", | ||
| 386 | spi->mode & ~MODEBITS); | ||
| 387 | return -EINVAL; | ||
| 388 | } | ||
| 389 | |||
| 390 | /* speed zero convention is used by some upper layers */ | ||
| 391 | bus_hz = clk_get_rate(as->clk); | ||
| 392 | if (spi->max_speed_hz) { | ||
| 393 | /* assume div32/fdiv/mbz == 0 */ | ||
| 394 | if (!as->new_1) | ||
| 395 | bus_hz /= 2; | ||
| 396 | scbr = ((bus_hz + spi->max_speed_hz - 1) | ||
| 397 | / spi->max_speed_hz); | ||
| 398 | if (scbr >= (1 << SPI_SCBR_SIZE)) { | ||
| 399 | dev_dbg(&spi->dev, "setup: %d Hz too slow, scbr %u\n", | ||
| 400 | spi->max_speed_hz, scbr); | ||
| 401 | return -EINVAL; | ||
| 402 | } | ||
| 403 | } else | ||
| 404 | scbr = 0xff; | ||
| 405 | sck_hz = bus_hz / scbr; | ||
| 406 | |||
| 407 | csr = SPI_BF(SCBR, scbr) | SPI_BF(BITS, bits - 8); | ||
| 408 | if (spi->mode & SPI_CPOL) | ||
| 409 | csr |= SPI_BIT(CPOL); | ||
| 410 | if (!(spi->mode & SPI_CPHA)) | ||
| 411 | csr |= SPI_BIT(NCPHA); | ||
| 412 | |||
| 413 | /* TODO: DLYBS and DLYBCT */ | ||
| 414 | csr |= SPI_BF(DLYBS, 10); | ||
| 415 | csr |= SPI_BF(DLYBCT, 10); | ||
| 416 | |||
| 417 | /* chipselect must have been muxed as GPIO (e.g. in board setup) */ | ||
| 418 | npcs_pin = (unsigned int)spi->controller_data; | ||
| 419 | if (!spi->controller_state) { | ||
| 420 | ret = gpio_request(npcs_pin, "spi_npcs"); | ||
| 421 | if (ret) | ||
| 422 | return ret; | ||
| 423 | spi->controller_state = (void *)npcs_pin; | ||
| 424 | gpio_direction_output(npcs_pin); | ||
| 425 | } | ||
| 426 | |||
| 427 | dev_dbg(&spi->dev, | ||
| 428 | "setup: %lu Hz bpw %u mode 0x%x -> csr%d %08x\n", | ||
| 429 | sck_hz, bits, spi->mode, spi->chip_select, csr); | ||
| 430 | |||
| 431 | spi_writel(as, CSR0 + 4 * spi->chip_select, csr); | ||
| 432 | |||
| 433 | return 0; | ||
| 434 | } | ||
| 435 | |||
| 436 | static int atmel_spi_transfer(struct spi_device *spi, struct spi_message *msg) | ||
| 437 | { | ||
| 438 | struct atmel_spi *as; | ||
| 439 | struct spi_transfer *xfer; | ||
| 440 | unsigned long flags; | ||
| 441 | struct device *controller = spi->master->cdev.dev; | ||
| 442 | |||
| 443 | as = spi_master_get_devdata(spi->master); | ||
| 444 | |||
| 445 | dev_dbg(controller, "new message %p submitted for %s\n", | ||
| 446 | msg, spi->dev.bus_id); | ||
| 447 | |||
| 448 | if (unlikely(list_empty(&msg->transfers) | ||
| 449 | || !spi->max_speed_hz)) | ||
| 450 | return -EINVAL; | ||
| 451 | |||
| 452 | if (as->stopping) | ||
| 453 | return -ESHUTDOWN; | ||
| 454 | |||
| 455 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | ||
| 456 | if (!(xfer->tx_buf || xfer->rx_buf)) { | ||
| 457 | dev_dbg(&spi->dev, "missing rx or tx buf\n"); | ||
| 458 | return -EINVAL; | ||
| 459 | } | ||
| 460 | |||
| 461 | /* FIXME implement these protocol options!! */ | ||
| 462 | if (xfer->bits_per_word || xfer->speed_hz) { | ||
| 463 | dev_dbg(&spi->dev, "no protocol options yet\n"); | ||
| 464 | return -ENOPROTOOPT; | ||
| 465 | } | ||
| 466 | } | ||
| 467 | |||
| 468 | /* scrub dcache "early" */ | ||
| 469 | if (!msg->is_dma_mapped) { | ||
| 470 | list_for_each_entry(xfer, &msg->transfers, transfer_list) | ||
| 471 | atmel_spi_dma_map_xfer(as, xfer); | ||
| 472 | } | ||
| 473 | |||
| 474 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | ||
| 475 | dev_dbg(controller, | ||
| 476 | " xfer %p: len %u tx %p/%08x rx %p/%08x\n", | ||
| 477 | xfer, xfer->len, | ||
| 478 | xfer->tx_buf, xfer->tx_dma, | ||
| 479 | xfer->rx_buf, xfer->rx_dma); | ||
| 480 | } | ||
| 481 | |||
| 482 | msg->status = -EINPROGRESS; | ||
| 483 | msg->actual_length = 0; | ||
| 484 | |||
| 485 | spin_lock_irqsave(&as->lock, flags); | ||
| 486 | list_add_tail(&msg->queue, &as->queue); | ||
| 487 | if (!as->current_transfer) | ||
| 488 | atmel_spi_next_message(spi->master); | ||
| 489 | spin_unlock_irqrestore(&as->lock, flags); | ||
| 490 | |||
| 491 | return 0; | ||
| 492 | } | ||
| 493 | |||
| 494 | static void atmel_spi_cleanup(const struct spi_device *spi) | ||
| 495 | { | ||
| 496 | if (spi->controller_state) | ||
| 497 | gpio_free((unsigned int)spi->controller_data); | ||
| 498 | } | ||
| 499 | |||
| 500 | /*-------------------------------------------------------------------------*/ | ||
| 501 | |||
| 502 | static int __init atmel_spi_probe(struct platform_device *pdev) | ||
| 503 | { | ||
| 504 | struct resource *regs; | ||
| 505 | int irq; | ||
| 506 | struct clk *clk; | ||
| 507 | int ret; | ||
| 508 | struct spi_master *master; | ||
| 509 | struct atmel_spi *as; | ||
| 510 | |||
| 511 | regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); | ||
| 512 | if (!regs) | ||
| 513 | return -ENXIO; | ||
| 514 | |||
| 515 | irq = platform_get_irq(pdev, 0); | ||
| 516 | if (irq < 0) | ||
| 517 | return irq; | ||
| 518 | |||
| 519 | clk = clk_get(&pdev->dev, "spi_clk"); | ||
| 520 | if (IS_ERR(clk)) | ||
| 521 | return PTR_ERR(clk); | ||
| 522 | |||
| 523 | /* setup spi core then atmel-specific driver state */ | ||
| 524 | ret = -ENOMEM; | ||
| 525 | master = spi_alloc_master(&pdev->dev, sizeof *as); | ||
| 526 | if (!master) | ||
| 527 | goto out_free; | ||
| 528 | |||
| 529 | master->bus_num = pdev->id; | ||
| 530 | master->num_chipselect = 4; | ||
| 531 | master->setup = atmel_spi_setup; | ||
| 532 | master->transfer = atmel_spi_transfer; | ||
| 533 | master->cleanup = atmel_spi_cleanup; | ||
| 534 | platform_set_drvdata(pdev, master); | ||
| 535 | |||
| 536 | as = spi_master_get_devdata(master); | ||
| 537 | |||
| 538 | as->buffer = dma_alloc_coherent(&pdev->dev, BUFFER_SIZE, | ||
| 539 | &as->buffer_dma, GFP_KERNEL); | ||
| 540 | if (!as->buffer) | ||
| 541 | goto out_free; | ||
| 542 | |||
| 543 | spin_lock_init(&as->lock); | ||
| 544 | INIT_LIST_HEAD(&as->queue); | ||
| 545 | as->pdev = pdev; | ||
| 546 | as->regs = ioremap(regs->start, (regs->end - regs->start) + 1); | ||
| 547 | if (!as->regs) | ||
| 548 | goto out_free_buffer; | ||
| 549 | as->irq = irq; | ||
| 550 | as->clk = clk; | ||
| 551 | #ifdef CONFIG_ARCH_AT91 | ||
| 552 | if (!cpu_is_at91rm9200()) | ||
| 553 | as->new_1 = 1; | ||
| 554 | #endif | ||
| 555 | |||
| 556 | ret = request_irq(irq, atmel_spi_interrupt, 0, | ||
| 557 | pdev->dev.bus_id, master); | ||
| 558 | if (ret) | ||
| 559 | goto out_unmap_regs; | ||
| 560 | |||
| 561 | /* Initialize the hardware */ | ||
| 562 | clk_enable(clk); | ||
| 563 | spi_writel(as, CR, SPI_BIT(SWRST)); | ||
| 564 | spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS)); | ||
| 565 | spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); | ||
| 566 | spi_writel(as, CR, SPI_BIT(SPIEN)); | ||
| 567 | |||
| 568 | /* go! */ | ||
| 569 | dev_info(&pdev->dev, "Atmel SPI Controller at 0x%08lx (irq %d)\n", | ||
| 570 | (unsigned long)regs->start, irq); | ||
| 571 | |||
| 572 | ret = spi_register_master(master); | ||
| 573 | if (ret) | ||
| 574 | goto out_reset_hw; | ||
| 575 | |||
| 576 | return 0; | ||
| 577 | |||
| 578 | out_reset_hw: | ||
| 579 | spi_writel(as, CR, SPI_BIT(SWRST)); | ||
| 580 | clk_disable(clk); | ||
| 581 | free_irq(irq, master); | ||
| 582 | out_unmap_regs: | ||
| 583 | iounmap(as->regs); | ||
| 584 | out_free_buffer: | ||
| 585 | dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer, | ||
| 586 | as->buffer_dma); | ||
| 587 | out_free: | ||
| 588 | clk_put(clk); | ||
| 589 | spi_master_put(master); | ||
| 590 | return ret; | ||
| 591 | } | ||
| 592 | |||
| 593 | static int __exit atmel_spi_remove(struct platform_device *pdev) | ||
| 594 | { | ||
| 595 | struct spi_master *master = platform_get_drvdata(pdev); | ||
| 596 | struct atmel_spi *as = spi_master_get_devdata(master); | ||
| 597 | struct spi_message *msg; | ||
| 598 | |||
| 599 | /* reset the hardware and block queue progress */ | ||
| 600 | spin_lock_irq(&as->lock); | ||
| 601 | as->stopping = 1; | ||
| 602 | spi_writel(as, CR, SPI_BIT(SWRST)); | ||
| 603 | spi_readl(as, SR); | ||
| 604 | spin_unlock_irq(&as->lock); | ||
| 605 | |||
| 606 | /* Terminate remaining queued transfers */ | ||
| 607 | list_for_each_entry(msg, &as->queue, queue) { | ||
| 608 | /* REVISIT unmapping the dma is a NOP on ARM and AVR32 | ||
| 609 | * but we shouldn't depend on that... | ||
| 610 | */ | ||
| 611 | msg->status = -ESHUTDOWN; | ||
| 612 | msg->complete(msg->context); | ||
| 613 | } | ||
| 614 | |||
| 615 | dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer, | ||
| 616 | as->buffer_dma); | ||
| 617 | |||
| 618 | clk_disable(as->clk); | ||
| 619 | clk_put(as->clk); | ||
| 620 | free_irq(as->irq, master); | ||
| 621 | iounmap(as->regs); | ||
| 622 | |||
| 623 | spi_unregister_master(master); | ||
| 624 | |||
| 625 | return 0; | ||
| 626 | } | ||
| 627 | |||
| 628 | #ifdef CONFIG_PM | ||
| 629 | |||
| 630 | static int atmel_spi_suspend(struct platform_device *pdev, pm_message_t mesg) | ||
| 631 | { | ||
| 632 | struct spi_master *master = platform_get_drvdata(pdev); | ||
| 633 | struct atmel_spi *as = spi_master_get_devdata(master); | ||
| 634 | |||
| 635 | clk_disable(as->clk); | ||
| 636 | return 0; | ||
| 637 | } | ||
| 638 | |||
| 639 | static int atmel_spi_resume(struct platform_device *pdev) | ||
| 640 | { | ||
| 641 | struct spi_master *master = platform_get_drvdata(pdev); | ||
| 642 | struct atmel_spi *as = spi_master_get_devdata(master); | ||
| 643 | |||
| 644 | clk_enable(as->clk); | ||
| 645 | return 0; | ||
| 646 | } | ||
| 647 | |||
| 648 | #else | ||
| 649 | #define atmel_spi_suspend NULL | ||
| 650 | #define atmel_spi_resume NULL | ||
| 651 | #endif | ||
| 652 | |||
| 653 | |||
| 654 | static struct platform_driver atmel_spi_driver = { | ||
| 655 | .driver = { | ||
| 656 | .name = "atmel_spi", | ||
| 657 | .owner = THIS_MODULE, | ||
| 658 | }, | ||
| 659 | .suspend = atmel_spi_suspend, | ||
| 660 | .resume = atmel_spi_resume, | ||
| 661 | .remove = __exit_p(atmel_spi_remove), | ||
| 662 | }; | ||
| 663 | |||
| 664 | static int __init atmel_spi_init(void) | ||
| 665 | { | ||
| 666 | return platform_driver_probe(&atmel_spi_driver, atmel_spi_probe); | ||
| 667 | } | ||
| 668 | module_init(atmel_spi_init); | ||
| 669 | |||
| 670 | static void __exit atmel_spi_exit(void) | ||
| 671 | { | ||
| 672 | platform_driver_unregister(&atmel_spi_driver); | ||
| 673 | } | ||
| 674 | module_exit(atmel_spi_exit); | ||
| 675 | |||
| 676 | MODULE_DESCRIPTION("Atmel AT32/AT91 SPI Controller driver"); | ||
| 677 | MODULE_AUTHOR("Haavard Skinnemoen <hskinnemoen@atmel.com>"); | ||
| 678 | MODULE_LICENSE("GPL"); | ||
diff --git a/drivers/spi/atmel_spi.h b/drivers/spi/atmel_spi.h new file mode 100644 index 000000000000..6e06b6ad3a45 --- /dev/null +++ b/drivers/spi/atmel_spi.h | |||
| @@ -0,0 +1,167 @@ | |||
| 1 | /* | ||
| 2 | * Register definitions for Atmel Serial Peripheral Interface (SPI) | ||
| 3 | * | ||
| 4 | * Copyright (C) 2006 Atmel Corporation | ||
| 5 | * | ||
| 6 | * This program is free software; you can redistribute it and/or modify | ||
| 7 | * it under the terms of the GNU General Public License version 2 as | ||
| 8 | * published by the Free Software Foundation. | ||
| 9 | */ | ||
| 10 | #ifndef __ATMEL_SPI_H__ | ||
| 11 | #define __ATMEL_SPI_H__ | ||
| 12 | |||
| 13 | /* SPI register offsets */ | ||
| 14 | #define SPI_CR 0x0000 | ||
| 15 | #define SPI_MR 0x0004 | ||
| 16 | #define SPI_RDR 0x0008 | ||
| 17 | #define SPI_TDR 0x000c | ||
| 18 | #define SPI_SR 0x0010 | ||
| 19 | #define SPI_IER 0x0014 | ||
| 20 | #define SPI_IDR 0x0018 | ||
| 21 | #define SPI_IMR 0x001c | ||
| 22 | #define SPI_CSR0 0x0030 | ||
| 23 | #define SPI_CSR1 0x0034 | ||
| 24 | #define SPI_CSR2 0x0038 | ||
| 25 | #define SPI_CSR3 0x003c | ||
| 26 | #define SPI_RPR 0x0100 | ||
| 27 | #define SPI_RCR 0x0104 | ||
| 28 | #define SPI_TPR 0x0108 | ||
| 29 | #define SPI_TCR 0x010c | ||
| 30 | #define SPI_RNPR 0x0110 | ||
| 31 | #define SPI_RNCR 0x0114 | ||
| 32 | #define SPI_TNPR 0x0118 | ||
| 33 | #define SPI_TNCR 0x011c | ||
| 34 | #define SPI_PTCR 0x0120 | ||
| 35 | #define SPI_PTSR 0x0124 | ||
| 36 | |||
| 37 | /* Bitfields in CR */ | ||
| 38 | #define SPI_SPIEN_OFFSET 0 | ||
| 39 | #define SPI_SPIEN_SIZE 1 | ||
| 40 | #define SPI_SPIDIS_OFFSET 1 | ||
| 41 | #define SPI_SPIDIS_SIZE 1 | ||
| 42 | #define SPI_SWRST_OFFSET 7 | ||
| 43 | #define SPI_SWRST_SIZE 1 | ||
| 44 | #define SPI_LASTXFER_OFFSET 24 | ||
| 45 | #define SPI_LASTXFER_SIZE 1 | ||
| 46 | |||
| 47 | /* Bitfields in MR */ | ||
| 48 | #define SPI_MSTR_OFFSET 0 | ||
| 49 | #define SPI_MSTR_SIZE 1 | ||
| 50 | #define SPI_PS_OFFSET 1 | ||
| 51 | #define SPI_PS_SIZE 1 | ||
| 52 | #define SPI_PCSDEC_OFFSET 2 | ||
| 53 | #define SPI_PCSDEC_SIZE 1 | ||
| 54 | #define SPI_FDIV_OFFSET 3 | ||
| 55 | #define SPI_FDIV_SIZE 1 | ||
| 56 | #define SPI_MODFDIS_OFFSET 4 | ||
| 57 | #define SPI_MODFDIS_SIZE 1 | ||
| 58 | #define SPI_LLB_OFFSET 7 | ||
| 59 | #define SPI_LLB_SIZE 1 | ||
| 60 | #define SPI_PCS_OFFSET 16 | ||
| 61 | #define SPI_PCS_SIZE 4 | ||
| 62 | #define SPI_DLYBCS_OFFSET 24 | ||
| 63 | #define SPI_DLYBCS_SIZE 8 | ||
| 64 | |||
| 65 | /* Bitfields in RDR */ | ||
| 66 | #define SPI_RD_OFFSET 0 | ||
| 67 | #define SPI_RD_SIZE 16 | ||
| 68 | |||
| 69 | /* Bitfields in TDR */ | ||
| 70 | #define SPI_TD_OFFSET 0 | ||
| 71 | #define SPI_TD_SIZE 16 | ||
| 72 | |||
| 73 | /* Bitfields in SR */ | ||
| 74 | #define SPI_RDRF_OFFSET 0 | ||
| 75 | #define SPI_RDRF_SIZE 1 | ||
| 76 | #define SPI_TDRE_OFFSET 1 | ||
| 77 | #define SPI_TDRE_SIZE 1 | ||
| 78 | #define SPI_MODF_OFFSET 2 | ||
| 79 | #define SPI_MODF_SIZE 1 | ||
| 80 | #define SPI_OVRES_OFFSET 3 | ||
| 81 | #define SPI_OVRES_SIZE 1 | ||
| 82 | #define SPI_ENDRX_OFFSET 4 | ||
| 83 | #define SPI_ENDRX_SIZE 1 | ||
| 84 | #define SPI_ENDTX_OFFSET 5 | ||
| 85 | #define SPI_ENDTX_SIZE 1 | ||
| 86 | #define SPI_RXBUFF_OFFSET 6 | ||
| 87 | #define SPI_RXBUFF_SIZE 1 | ||
| 88 | #define SPI_TXBUFE_OFFSET 7 | ||
| 89 | #define SPI_TXBUFE_SIZE 1 | ||
| 90 | #define SPI_NSSR_OFFSET 8 | ||
| 91 | #define SPI_NSSR_SIZE 1 | ||
| 92 | #define SPI_TXEMPTY_OFFSET 9 | ||
| 93 | #define SPI_TXEMPTY_SIZE 1 | ||
| 94 | #define SPI_SPIENS_OFFSET 16 | ||
| 95 | #define SPI_SPIENS_SIZE 1 | ||
| 96 | |||
| 97 | /* Bitfields in CSR0 */ | ||
| 98 | #define SPI_CPOL_OFFSET 0 | ||
| 99 | #define SPI_CPOL_SIZE 1 | ||
| 100 | #define SPI_NCPHA_OFFSET 1 | ||
| 101 | #define SPI_NCPHA_SIZE 1 | ||
| 102 | #define SPI_CSAAT_OFFSET 3 | ||
| 103 | #define SPI_CSAAT_SIZE 1 | ||
| 104 | #define SPI_BITS_OFFSET 4 | ||
| 105 | #define SPI_BITS_SIZE 4 | ||
| 106 | #define SPI_SCBR_OFFSET 8 | ||
| 107 | #define SPI_SCBR_SIZE 8 | ||
| 108 | #define SPI_DLYBS_OFFSET 16 | ||
| 109 | #define SPI_DLYBS_SIZE 8 | ||
| 110 | #define SPI_DLYBCT_OFFSET 24 | ||
| 111 | #define SPI_DLYBCT_SIZE 8 | ||
| 112 | |||
| 113 | /* Bitfields in RCR */ | ||
| 114 | #define SPI_RXCTR_OFFSET 0 | ||
| 115 | #define SPI_RXCTR_SIZE 16 | ||
| 116 | |||
| 117 | /* Bitfields in TCR */ | ||
| 118 | #define SPI_TXCTR_OFFSET 0 | ||
| 119 | #define SPI_TXCTR_SIZE 16 | ||
| 120 | |||
| 121 | /* Bitfields in RNCR */ | ||
| 122 | #define SPI_RXNCR_OFFSET 0 | ||
| 123 | #define SPI_RXNCR_SIZE 16 | ||
| 124 | |||
| 125 | /* Bitfields in TNCR */ | ||
| 126 | #define SPI_TXNCR_OFFSET 0 | ||
| 127 | #define SPI_TXNCR_SIZE 16 | ||
| 128 | |||
| 129 | /* Bitfields in PTCR */ | ||
| 130 | #define SPI_RXTEN_OFFSET 0 | ||
| 131 | #define SPI_RXTEN_SIZE 1 | ||
| 132 | #define SPI_RXTDIS_OFFSET 1 | ||
| 133 | #define SPI_RXTDIS_SIZE 1 | ||
| 134 | #define SPI_TXTEN_OFFSET 8 | ||
| 135 | #define SPI_TXTEN_SIZE 1 | ||
| 136 | #define SPI_TXTDIS_OFFSET 9 | ||
| 137 | #define SPI_TXTDIS_SIZE 1 | ||
| 138 | |||
| 139 | /* Constants for BITS */ | ||
| 140 | #define SPI_BITS_8_BPT 0 | ||
| 141 | #define SPI_BITS_9_BPT 1 | ||
| 142 | #define SPI_BITS_10_BPT 2 | ||
| 143 | #define SPI_BITS_11_BPT 3 | ||
| 144 | #define SPI_BITS_12_BPT 4 | ||
| 145 | #define SPI_BITS_13_BPT 5 | ||
| 146 | #define SPI_BITS_14_BPT 6 | ||
| 147 | #define SPI_BITS_15_BPT 7 | ||
| 148 | #define SPI_BITS_16_BPT 8 | ||
| 149 | |||
| 150 | /* Bit manipulation macros */ | ||
| 151 | #define SPI_BIT(name) \ | ||
| 152 | (1 << SPI_##name##_OFFSET) | ||
| 153 | #define SPI_BF(name,value) \ | ||
| 154 | (((value) & ((1 << SPI_##name##_SIZE) - 1)) << SPI_##name##_OFFSET) | ||
| 155 | #define SPI_BFEXT(name,value) \ | ||
| 156 | (((value) >> SPI_##name##_OFFSET) & ((1 << SPI_##name##_SIZE) - 1)) | ||
| 157 | #define SPI_BFINS(name,value,old) \ | ||
| 158 | ( ((old) & ~(((1 << SPI_##name##_SIZE) - 1) << SPI_##name##_OFFSET)) \ | ||
| 159 | | SPI_BF(name,value)) | ||
| 160 | |||
| 161 | /* Register access macros */ | ||
| 162 | #define spi_readl(port,reg) \ | ||
| 163 | __raw_readl((port)->regs + SPI_##reg) | ||
| 164 | #define spi_writel(port,reg,value) \ | ||
| 165 | __raw_writel((value), (port)->regs + SPI_##reg) | ||
| 166 | |||
| 167 | #endif /* __ATMEL_SPI_H__ */ | ||
