1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (C) 2018 Exceet Electronics GmbH
4 * Copyright (C) 2018 Bootlin
6 * Author: Boris Brezillon <boris.brezillon@bootlin.com>
10 #include <dm/devres.h>
11 #include <linux/dmaengine.h>
12 #include <linux/pm_runtime.h>
13 #include "internals.h"
21 * spi_controller_dma_map_mem_op_data() - DMA-map the buffer attached to a
23 * @ctlr: the SPI controller requesting this dma_map()
24 * @op: the memory operation containing the buffer to map
25 * @sgt: a pointer to a non-initialized sg_table that will be filled by this
28 * Some controllers might want to do DMA on the data buffer embedded in @op.
29 * This helper prepares everything for you and provides a ready-to-use
30 * sg_table. This function is not intended to be called from spi drivers.
31 * Only SPI controller drivers should use it.
32 * Note that the caller must ensure the memory region pointed by
33 * op->data.buf.{in,out} is DMA-able before calling this function.
35 * Return: 0 in case of success, a negative error code otherwise.
37 int spi_controller_dma_map_mem_op_data(struct spi_controller *ctlr,
38 const struct spi_mem_op *op,
41 struct device *dmadev;
46 if (op->data.dir == SPI_MEM_DATA_OUT && ctlr->dma_tx)
47 dmadev = ctlr->dma_tx->device->dev;
48 else if (op->data.dir == SPI_MEM_DATA_IN && ctlr->dma_rx)
49 dmadev = ctlr->dma_rx->device->dev;
51 dmadev = ctlr->dev.parent;
56 return spi_map_buf(ctlr, dmadev, sgt, op->data.buf.in, op->data.nbytes,
57 op->data.dir == SPI_MEM_DATA_IN ?
58 DMA_FROM_DEVICE : DMA_TO_DEVICE);
60 EXPORT_SYMBOL_GPL(spi_controller_dma_map_mem_op_data);
63 * spi_controller_dma_unmap_mem_op_data() - DMA-unmap the buffer attached to a
65 * @ctlr: the SPI controller requesting this dma_unmap()
66 * @op: the memory operation containing the buffer to unmap
67 * @sgt: a pointer to an sg_table previously initialized by
68 * spi_controller_dma_map_mem_op_data()
70 * Some controllers might want to do DMA on the data buffer embedded in @op.
71 * This helper prepares things so that the CPU can access the
72 * op->data.buf.{in,out} buffer again.
74 * This function is not intended to be called from SPI drivers. Only SPI
75 * controller drivers should use it.
77 * This function should be called after the DMA operation has finished and is
78 * only valid if the previous spi_controller_dma_map_mem_op_data() call
81 * Return: 0 in case of success, a negative error code otherwise.
83 void spi_controller_dma_unmap_mem_op_data(struct spi_controller *ctlr,
84 const struct spi_mem_op *op,
87 struct device *dmadev;
92 if (op->data.dir == SPI_MEM_DATA_OUT && ctlr->dma_tx)
93 dmadev = ctlr->dma_tx->device->dev;
94 else if (op->data.dir == SPI_MEM_DATA_IN && ctlr->dma_rx)
95 dmadev = ctlr->dma_rx->device->dev;
97 dmadev = ctlr->dev.parent;
99 spi_unmap_buf(ctlr, dmadev, sgt,
100 op->data.dir == SPI_MEM_DATA_IN ?
101 DMA_FROM_DEVICE : DMA_TO_DEVICE);
103 EXPORT_SYMBOL_GPL(spi_controller_dma_unmap_mem_op_data);
104 #endif /* __UBOOT__ */
106 static int spi_check_buswidth_req(struct spi_slave *slave, u8 buswidth, bool tx)
108 u32 mode = slave->mode;
115 if ((tx && (mode & (SPI_TX_DUAL | SPI_TX_QUAD))) ||
116 (!tx && (mode & (SPI_RX_DUAL | SPI_RX_QUAD))))
122 if ((tx && (mode & SPI_TX_QUAD)) ||
123 (!tx && (mode & SPI_RX_QUAD)))
128 if ((tx && (mode & SPI_TX_OCTAL)) ||
129 (!tx && (mode & SPI_RX_OCTAL)))
141 bool spi_mem_default_supports_op(struct spi_slave *slave,
142 const struct spi_mem_op *op)
144 if (spi_check_buswidth_req(slave, op->cmd.buswidth, true))
147 if (op->addr.nbytes &&
148 spi_check_buswidth_req(slave, op->addr.buswidth, true))
151 if (op->dummy.nbytes &&
152 spi_check_buswidth_req(slave, op->dummy.buswidth, true))
155 if (op->data.nbytes &&
156 spi_check_buswidth_req(slave, op->data.buswidth,
157 op->data.dir == SPI_MEM_DATA_OUT))
162 EXPORT_SYMBOL_GPL(spi_mem_default_supports_op);
165 * spi_mem_supports_op() - Check if a memory device and the controller it is
166 * connected to support a specific memory operation
167 * @slave: the SPI device
168 * @op: the memory operation to check
170 * Some controllers are only supporting Single or Dual IOs, others might only
171 * support specific opcodes, or it can even be that the controller and device
172 * both support Quad IOs but the hardware prevents you from using it because
173 * only 2 IO lines are connected.
175 * This function checks whether a specific operation is supported.
177 * Return: true if @op is supported, false otherwise.
179 bool spi_mem_supports_op(struct spi_slave *slave,
180 const struct spi_mem_op *op)
182 struct udevice *bus = slave->dev->parent;
183 struct dm_spi_ops *ops = spi_get_ops(bus);
185 if (ops->mem_ops && ops->mem_ops->supports_op)
186 return ops->mem_ops->supports_op(slave, op);
188 return spi_mem_default_supports_op(slave, op);
190 EXPORT_SYMBOL_GPL(spi_mem_supports_op);
193 * spi_mem_exec_op() - Execute a memory operation
194 * @slave: the SPI device
195 * @op: the memory operation to execute
197 * Executes a memory operation.
199 * This function first checks that @op is supported and then tries to execute
202 * Return: 0 in case of success, a negative error code otherwise.
204 int spi_mem_exec_op(struct spi_slave *slave, const struct spi_mem_op *op)
206 struct udevice *bus = slave->dev->parent;
207 struct dm_spi_ops *ops = spi_get_ops(bus);
208 unsigned int pos = 0;
209 const u8 *tx_buf = NULL;
216 if (!spi_mem_supports_op(slave, op))
219 ret = spi_claim_bus(slave);
223 if (ops->mem_ops && ops->mem_ops->exec_op) {
226 * Flush the message queue before executing our SPI memory
227 * operation to prevent preemption of regular SPI transfers.
229 spi_flush_queue(ctlr);
231 if (ctlr->auto_runtime_pm) {
232 ret = pm_runtime_get_sync(ctlr->dev.parent);
235 "Failed to power device: %d\n",
241 mutex_lock(&ctlr->bus_lock_mutex);
242 mutex_lock(&ctlr->io_mutex);
244 ret = ops->mem_ops->exec_op(slave, op);
247 mutex_unlock(&ctlr->io_mutex);
248 mutex_unlock(&ctlr->bus_lock_mutex);
250 if (ctlr->auto_runtime_pm)
251 pm_runtime_put(ctlr->dev.parent);
255 * Some controllers only optimize specific paths (typically the
256 * read path) and expect the core to use the regular SPI
257 * interface in other cases.
259 if (!ret || ret != -ENOTSUPP) {
260 spi_release_bus(slave);
266 tmpbufsize = sizeof(op->cmd.opcode) + op->addr.nbytes +
270 * Allocate a buffer to transmit the CMD, ADDR cycles with kmalloc() so
271 * we're guaranteed that this buffer is DMA-able, as required by the
274 tmpbuf = kzalloc(tmpbufsize, GFP_KERNEL | GFP_DMA);
278 spi_message_init(&msg);
280 tmpbuf[0] = op->cmd.opcode;
281 xfers[xferpos].tx_buf = tmpbuf;
282 xfers[xferpos].len = sizeof(op->cmd.opcode);
283 xfers[xferpos].tx_nbits = op->cmd.buswidth;
284 spi_message_add_tail(&xfers[xferpos], &msg);
288 if (op->addr.nbytes) {
291 for (i = 0; i < op->addr.nbytes; i++)
292 tmpbuf[i + 1] = op->addr.val >>
293 (8 * (op->addr.nbytes - i - 1));
295 xfers[xferpos].tx_buf = tmpbuf + 1;
296 xfers[xferpos].len = op->addr.nbytes;
297 xfers[xferpos].tx_nbits = op->addr.buswidth;
298 spi_message_add_tail(&xfers[xferpos], &msg);
300 totalxferlen += op->addr.nbytes;
303 if (op->dummy.nbytes) {
304 memset(tmpbuf + op->addr.nbytes + 1, 0xff, op->dummy.nbytes);
305 xfers[xferpos].tx_buf = tmpbuf + op->addr.nbytes + 1;
306 xfers[xferpos].len = op->dummy.nbytes;
307 xfers[xferpos].tx_nbits = op->dummy.buswidth;
308 spi_message_add_tail(&xfers[xferpos], &msg);
310 totalxferlen += op->dummy.nbytes;
313 if (op->data.nbytes) {
314 if (op->data.dir == SPI_MEM_DATA_IN) {
315 xfers[xferpos].rx_buf = op->data.buf.in;
316 xfers[xferpos].rx_nbits = op->data.buswidth;
318 xfers[xferpos].tx_buf = op->data.buf.out;
319 xfers[xferpos].tx_nbits = op->data.buswidth;
322 xfers[xferpos].len = op->data.nbytes;
323 spi_message_add_tail(&xfers[xferpos], &msg);
325 totalxferlen += op->data.nbytes;
328 ret = spi_sync(slave, &msg);
335 if (msg.actual_length != totalxferlen)
339 if (op->data.nbytes) {
340 if (op->data.dir == SPI_MEM_DATA_IN)
341 rx_buf = op->data.buf.in;
343 tx_buf = op->data.buf.out;
346 op_len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
349 * Avoid using malloc() here so that we can use this code in SPL where
350 * simple malloc may be used. That implementation does not allow free()
351 * so repeated calls to this code can exhaust the space.
353 * The value of op_len is small, since it does not include the actual
354 * data being sent, only the op-code and address. In fact, it should be
355 * possible to just use a small fixed value here instead of op_len.
359 op_buf[pos++] = op->cmd.opcode;
361 if (op->addr.nbytes) {
362 for (i = 0; i < op->addr.nbytes; i++)
363 op_buf[pos + i] = op->addr.val >>
364 (8 * (op->addr.nbytes - i - 1));
366 pos += op->addr.nbytes;
369 if (op->dummy.nbytes)
370 memset(op_buf + pos, 0xff, op->dummy.nbytes);
372 /* 1st transfer: opcode + address + dummy cycles */
373 flag = SPI_XFER_BEGIN;
374 /* Make sure to set END bit if no tx or rx data messages follow */
375 if (!tx_buf && !rx_buf)
376 flag |= SPI_XFER_END;
378 ret = spi_xfer(slave, op_len * 8, op_buf, NULL, flag);
382 /* 2nd transfer: rx or tx data path */
383 if (tx_buf || rx_buf) {
384 ret = spi_xfer(slave, op->data.nbytes * 8, tx_buf,
385 rx_buf, SPI_XFER_END);
390 spi_release_bus(slave);
392 for (i = 0; i < pos; i++)
393 debug("%02x ", op_buf[i]);
395 tx_buf || rx_buf ? op->data.nbytes : 0,
396 tx_buf || rx_buf ? (tx_buf ? "out" : "in") : "-");
397 for (i = 0; i < op->data.nbytes; i++)
398 debug("%02x ", tx_buf ? tx_buf[i] : rx_buf[i]);
399 debug("[ret %d]\n", ret);
403 #endif /* __UBOOT__ */
407 EXPORT_SYMBOL_GPL(spi_mem_exec_op);
410 * spi_mem_adjust_op_size() - Adjust the data size of a SPI mem operation to
411 * match controller limitations
412 * @slave: the SPI device
413 * @op: the operation to adjust
415 * Some controllers have FIFO limitations and must split a data transfer
416 * operation into multiple ones, others require a specific alignment for
417 * optimized accesses. This function allows SPI mem drivers to split a single
418 * operation into multiple sub-operations when required.
420 * Return: a negative error code if the controller can't properly adjust @op,
421 * 0 otherwise. Note that @op->data.nbytes will be updated if @op
422 * can't be handled in a single step.
424 int spi_mem_adjust_op_size(struct spi_slave *slave, struct spi_mem_op *op)
426 struct udevice *bus = slave->dev->parent;
427 struct dm_spi_ops *ops = spi_get_ops(bus);
429 if (ops->mem_ops && ops->mem_ops->adjust_op_size)
430 return ops->mem_ops->adjust_op_size(slave, op);
432 if (!ops->mem_ops || !ops->mem_ops->exec_op) {
435 len = sizeof(op->cmd.opcode) + op->addr.nbytes +
437 if (slave->max_write_size && len > slave->max_write_size)
440 if (op->data.dir == SPI_MEM_DATA_IN) {
441 if (slave->max_read_size)
442 op->data.nbytes = min(op->data.nbytes,
443 slave->max_read_size);
444 } else if (slave->max_write_size) {
445 op->data.nbytes = min(op->data.nbytes,
446 slave->max_write_size - len);
449 if (!op->data.nbytes)
455 EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);
458 static inline struct spi_mem_driver *to_spi_mem_drv(struct device_driver *drv)
460 return container_of(drv, struct spi_mem_driver, spidrv.driver);
463 static int spi_mem_probe(struct spi_device *spi)
465 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
468 mem = devm_kzalloc(&spi->dev, sizeof(*mem), GFP_KERNEL);
473 spi_set_drvdata(spi, mem);
475 return memdrv->probe(mem);
478 static int spi_mem_remove(struct spi_device *spi)
480 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
481 struct spi_mem *mem = spi_get_drvdata(spi);
484 return memdrv->remove(mem);
489 static void spi_mem_shutdown(struct spi_device *spi)
491 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
492 struct spi_mem *mem = spi_get_drvdata(spi);
494 if (memdrv->shutdown)
495 memdrv->shutdown(mem);
499 * spi_mem_driver_register_with_owner() - Register a SPI memory driver
500 * @memdrv: the SPI memory driver to register
501 * @owner: the owner of this driver
503 * Registers a SPI memory driver.
505 * Return: 0 in case of success, a negative error core otherwise.
508 int spi_mem_driver_register_with_owner(struct spi_mem_driver *memdrv,
509 struct module *owner)
511 memdrv->spidrv.probe = spi_mem_probe;
512 memdrv->spidrv.remove = spi_mem_remove;
513 memdrv->spidrv.shutdown = spi_mem_shutdown;
515 return __spi_register_driver(owner, &memdrv->spidrv);
517 EXPORT_SYMBOL_GPL(spi_mem_driver_register_with_owner);
520 * spi_mem_driver_unregister_with_owner() - Unregister a SPI memory driver
521 * @memdrv: the SPI memory driver to unregister
523 * Unregisters a SPI memory driver.
525 void spi_mem_driver_unregister(struct spi_mem_driver *memdrv)
527 spi_unregister_driver(&memdrv->spidrv);
529 EXPORT_SYMBOL_GPL(spi_mem_driver_unregister);
530 #endif /* __UBOOT__ */