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>
11 #include <dm/devres.h>
12 #include <linux/dmaengine.h>
13 #include <linux/pm_runtime.h>
14 #include "internals.h"
23 #include <dm/device_compat.h>
28 * spi_controller_dma_map_mem_op_data() - DMA-map the buffer attached to a
30 * @ctlr: the SPI controller requesting this dma_map()
31 * @op: the memory operation containing the buffer to map
32 * @sgt: a pointer to a non-initialized sg_table that will be filled by this
35 * Some controllers might want to do DMA on the data buffer embedded in @op.
36 * This helper prepares everything for you and provides a ready-to-use
37 * sg_table. This function is not intended to be called from spi drivers.
38 * Only SPI controller drivers should use it.
39 * Note that the caller must ensure the memory region pointed by
40 * op->data.buf.{in,out} is DMA-able before calling this function.
42 * Return: 0 in case of success, a negative error code otherwise.
44 int spi_controller_dma_map_mem_op_data(struct spi_controller *ctlr,
45 const struct spi_mem_op *op,
48 struct device *dmadev;
53 if (op->data.dir == SPI_MEM_DATA_OUT && ctlr->dma_tx)
54 dmadev = ctlr->dma_tx->device->dev;
55 else if (op->data.dir == SPI_MEM_DATA_IN && ctlr->dma_rx)
56 dmadev = ctlr->dma_rx->device->dev;
58 dmadev = ctlr->dev.parent;
63 return spi_map_buf(ctlr, dmadev, sgt, op->data.buf.in, op->data.nbytes,
64 op->data.dir == SPI_MEM_DATA_IN ?
65 DMA_FROM_DEVICE : DMA_TO_DEVICE);
67 EXPORT_SYMBOL_GPL(spi_controller_dma_map_mem_op_data);
70 * spi_controller_dma_unmap_mem_op_data() - DMA-unmap the buffer attached to a
72 * @ctlr: the SPI controller requesting this dma_unmap()
73 * @op: the memory operation containing the buffer to unmap
74 * @sgt: a pointer to an sg_table previously initialized by
75 * spi_controller_dma_map_mem_op_data()
77 * Some controllers might want to do DMA on the data buffer embedded in @op.
78 * This helper prepares things so that the CPU can access the
79 * op->data.buf.{in,out} buffer again.
81 * This function is not intended to be called from SPI drivers. Only SPI
82 * controller drivers should use it.
84 * This function should be called after the DMA operation has finished and is
85 * only valid if the previous spi_controller_dma_map_mem_op_data() call
88 * Return: 0 in case of success, a negative error code otherwise.
90 void spi_controller_dma_unmap_mem_op_data(struct spi_controller *ctlr,
91 const struct spi_mem_op *op,
94 struct device *dmadev;
99 if (op->data.dir == SPI_MEM_DATA_OUT && ctlr->dma_tx)
100 dmadev = ctlr->dma_tx->device->dev;
101 else if (op->data.dir == SPI_MEM_DATA_IN && ctlr->dma_rx)
102 dmadev = ctlr->dma_rx->device->dev;
104 dmadev = ctlr->dev.parent;
106 spi_unmap_buf(ctlr, dmadev, sgt,
107 op->data.dir == SPI_MEM_DATA_IN ?
108 DMA_FROM_DEVICE : DMA_TO_DEVICE);
110 EXPORT_SYMBOL_GPL(spi_controller_dma_unmap_mem_op_data);
111 #endif /* __UBOOT__ */
113 static int spi_check_buswidth_req(struct spi_slave *slave, u8 buswidth, bool tx)
115 u32 mode = slave->mode;
122 if ((tx && (mode & (SPI_TX_DUAL | SPI_TX_QUAD))) ||
123 (!tx && (mode & (SPI_RX_DUAL | SPI_RX_QUAD))))
129 if ((tx && (mode & SPI_TX_QUAD)) ||
130 (!tx && (mode & SPI_RX_QUAD)))
135 if ((tx && (mode & SPI_TX_OCTAL)) ||
136 (!tx && (mode & SPI_RX_OCTAL)))
148 static bool spi_mem_check_buswidth(struct spi_slave *slave,
149 const struct spi_mem_op *op)
151 if (spi_check_buswidth_req(slave, op->cmd.buswidth, true))
154 if (op->addr.nbytes &&
155 spi_check_buswidth_req(slave, op->addr.buswidth, true))
158 if (op->dummy.nbytes &&
159 spi_check_buswidth_req(slave, op->dummy.buswidth, true))
162 if (op->data.dir != SPI_MEM_NO_DATA &&
163 spi_check_buswidth_req(slave, op->data.buswidth,
164 op->data.dir == SPI_MEM_DATA_OUT))
170 bool spi_mem_dtr_supports_op(struct spi_slave *slave,
171 const struct spi_mem_op *op)
173 if (op->cmd.buswidth == 8 && op->cmd.nbytes % 2)
176 if (op->addr.nbytes && op->addr.buswidth == 8 && op->addr.nbytes % 2)
179 if (op->dummy.nbytes && op->dummy.buswidth == 8 && op->dummy.nbytes % 2)
182 if (op->data.dir != SPI_MEM_NO_DATA &&
183 op->dummy.buswidth == 8 && op->data.nbytes % 2)
186 return spi_mem_check_buswidth(slave, op);
188 EXPORT_SYMBOL_GPL(spi_mem_dtr_supports_op);
190 bool spi_mem_default_supports_op(struct spi_slave *slave,
191 const struct spi_mem_op *op)
193 if (op->cmd.dtr || op->addr.dtr || op->dummy.dtr || op->data.dtr)
196 if (op->cmd.nbytes != 1)
199 return spi_mem_check_buswidth(slave, op);
201 EXPORT_SYMBOL_GPL(spi_mem_default_supports_op);
204 * spi_mem_supports_op() - Check if a memory device and the controller it is
205 * connected to support a specific memory operation
206 * @slave: the SPI device
207 * @op: the memory operation to check
209 * Some controllers are only supporting Single or Dual IOs, others might only
210 * support specific opcodes, or it can even be that the controller and device
211 * both support Quad IOs but the hardware prevents you from using it because
212 * only 2 IO lines are connected.
214 * This function checks whether a specific operation is supported.
216 * Return: true if @op is supported, false otherwise.
218 bool spi_mem_supports_op(struct spi_slave *slave,
219 const struct spi_mem_op *op)
221 struct udevice *bus = slave->dev->parent;
222 struct dm_spi_ops *ops = spi_get_ops(bus);
224 if (ops->mem_ops && ops->mem_ops->supports_op)
225 return ops->mem_ops->supports_op(slave, op);
227 return spi_mem_default_supports_op(slave, op);
229 EXPORT_SYMBOL_GPL(spi_mem_supports_op);
232 * spi_mem_exec_op() - Execute a memory operation
233 * @slave: the SPI device
234 * @op: the memory operation to execute
236 * Executes a memory operation.
238 * This function first checks that @op is supported and then tries to execute
241 * Return: 0 in case of success, a negative error code otherwise.
243 int spi_mem_exec_op(struct spi_slave *slave, const struct spi_mem_op *op)
245 struct udevice *bus = slave->dev->parent;
246 struct dm_spi_ops *ops = spi_get_ops(bus);
247 unsigned int pos = 0;
248 const u8 *tx_buf = NULL;
255 if (!spi_mem_supports_op(slave, op))
258 ret = spi_claim_bus(slave);
262 if (ops->mem_ops && ops->mem_ops->exec_op) {
265 * Flush the message queue before executing our SPI memory
266 * operation to prevent preemption of regular SPI transfers.
268 spi_flush_queue(ctlr);
270 if (ctlr->auto_runtime_pm) {
271 ret = pm_runtime_get_sync(ctlr->dev.parent);
274 "Failed to power device: %d\n",
280 mutex_lock(&ctlr->bus_lock_mutex);
281 mutex_lock(&ctlr->io_mutex);
283 ret = ops->mem_ops->exec_op(slave, op);
286 mutex_unlock(&ctlr->io_mutex);
287 mutex_unlock(&ctlr->bus_lock_mutex);
289 if (ctlr->auto_runtime_pm)
290 pm_runtime_put(ctlr->dev.parent);
294 * Some controllers only optimize specific paths (typically the
295 * read path) and expect the core to use the regular SPI
296 * interface in other cases.
298 if (!ret || ret != -ENOTSUPP) {
299 spi_release_bus(slave);
305 tmpbufsize = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes;
308 * Allocate a buffer to transmit the CMD, ADDR cycles with kmalloc() so
309 * we're guaranteed that this buffer is DMA-able, as required by the
312 tmpbuf = kzalloc(tmpbufsize, GFP_KERNEL | GFP_DMA);
316 spi_message_init(&msg);
318 tmpbuf[0] = op->cmd.opcode;
319 xfers[xferpos].tx_buf = tmpbuf;
320 xfers[xferpos].len = op->cmd.nbytes;
321 xfers[xferpos].tx_nbits = op->cmd.buswidth;
322 spi_message_add_tail(&xfers[xferpos], &msg);
326 if (op->addr.nbytes) {
329 for (i = 0; i < op->addr.nbytes; i++)
330 tmpbuf[i + 1] = op->addr.val >>
331 (8 * (op->addr.nbytes - i - 1));
333 xfers[xferpos].tx_buf = tmpbuf + 1;
334 xfers[xferpos].len = op->addr.nbytes;
335 xfers[xferpos].tx_nbits = op->addr.buswidth;
336 spi_message_add_tail(&xfers[xferpos], &msg);
338 totalxferlen += op->addr.nbytes;
341 if (op->dummy.nbytes) {
342 memset(tmpbuf + op->addr.nbytes + 1, 0xff, op->dummy.nbytes);
343 xfers[xferpos].tx_buf = tmpbuf + op->addr.nbytes + 1;
344 xfers[xferpos].len = op->dummy.nbytes;
345 xfers[xferpos].tx_nbits = op->dummy.buswidth;
346 spi_message_add_tail(&xfers[xferpos], &msg);
348 totalxferlen += op->dummy.nbytes;
351 if (op->data.nbytes) {
352 if (op->data.dir == SPI_MEM_DATA_IN) {
353 xfers[xferpos].rx_buf = op->data.buf.in;
354 xfers[xferpos].rx_nbits = op->data.buswidth;
356 xfers[xferpos].tx_buf = op->data.buf.out;
357 xfers[xferpos].tx_nbits = op->data.buswidth;
360 xfers[xferpos].len = op->data.nbytes;
361 spi_message_add_tail(&xfers[xferpos], &msg);
363 totalxferlen += op->data.nbytes;
366 ret = spi_sync(slave, &msg);
373 if (msg.actual_length != totalxferlen)
377 if (op->data.nbytes) {
378 if (op->data.dir == SPI_MEM_DATA_IN)
379 rx_buf = op->data.buf.in;
381 tx_buf = op->data.buf.out;
384 op_len = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes;
387 * Avoid using malloc() here so that we can use this code in SPL where
388 * simple malloc may be used. That implementation does not allow free()
389 * so repeated calls to this code can exhaust the space.
391 * The value of op_len is small, since it does not include the actual
392 * data being sent, only the op-code and address. In fact, it should be
393 * possible to just use a small fixed value here instead of op_len.
397 op_buf[pos++] = op->cmd.opcode;
399 if (op->addr.nbytes) {
400 for (i = 0; i < op->addr.nbytes; i++)
401 op_buf[pos + i] = op->addr.val >>
402 (8 * (op->addr.nbytes - i - 1));
404 pos += op->addr.nbytes;
407 if (op->dummy.nbytes)
408 memset(op_buf + pos, 0xff, op->dummy.nbytes);
410 /* 1st transfer: opcode + address + dummy cycles */
411 flag = SPI_XFER_BEGIN;
412 /* Make sure to set END bit if no tx or rx data messages follow */
413 if (!tx_buf && !rx_buf)
414 flag |= SPI_XFER_END;
416 ret = spi_xfer(slave, op_len * 8, op_buf, NULL, flag);
420 /* 2nd transfer: rx or tx data path */
421 if (tx_buf || rx_buf) {
422 ret = spi_xfer(slave, op->data.nbytes * 8, tx_buf,
423 rx_buf, SPI_XFER_END);
428 spi_release_bus(slave);
430 for (i = 0; i < pos; i++)
431 debug("%02x ", op_buf[i]);
433 tx_buf || rx_buf ? op->data.nbytes : 0,
434 tx_buf || rx_buf ? (tx_buf ? "out" : "in") : "-");
435 for (i = 0; i < op->data.nbytes; i++)
436 debug("%02x ", tx_buf ? tx_buf[i] : rx_buf[i]);
437 debug("[ret %d]\n", ret);
441 #endif /* __UBOOT__ */
445 EXPORT_SYMBOL_GPL(spi_mem_exec_op);
448 * spi_mem_adjust_op_size() - Adjust the data size of a SPI mem operation to
449 * match controller limitations
450 * @slave: the SPI device
451 * @op: the operation to adjust
453 * Some controllers have FIFO limitations and must split a data transfer
454 * operation into multiple ones, others require a specific alignment for
455 * optimized accesses. This function allows SPI mem drivers to split a single
456 * operation into multiple sub-operations when required.
458 * Return: a negative error code if the controller can't properly adjust @op,
459 * 0 otherwise. Note that @op->data.nbytes will be updated if @op
460 * can't be handled in a single step.
462 int spi_mem_adjust_op_size(struct spi_slave *slave, struct spi_mem_op *op)
464 struct udevice *bus = slave->dev->parent;
465 struct dm_spi_ops *ops = spi_get_ops(bus);
467 if (ops->mem_ops && ops->mem_ops->adjust_op_size)
468 return ops->mem_ops->adjust_op_size(slave, op);
470 if (!ops->mem_ops || !ops->mem_ops->exec_op) {
473 len = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes;
474 if (slave->max_write_size && len > slave->max_write_size)
477 if (op->data.dir == SPI_MEM_DATA_IN) {
478 if (slave->max_read_size)
479 op->data.nbytes = min(op->data.nbytes,
480 slave->max_read_size);
481 } else if (slave->max_write_size) {
482 op->data.nbytes = min(op->data.nbytes,
483 slave->max_write_size - len);
486 if (!op->data.nbytes)
492 EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);
495 static inline struct spi_mem_driver *to_spi_mem_drv(struct device_driver *drv)
497 return container_of(drv, struct spi_mem_driver, spidrv.driver);
500 static int spi_mem_probe(struct spi_device *spi)
502 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
505 mem = devm_kzalloc(&spi->dev, sizeof(*mem), GFP_KERNEL);
510 spi_set_drvdata(spi, mem);
512 return memdrv->probe(mem);
515 static int spi_mem_remove(struct spi_device *spi)
517 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
518 struct spi_mem *mem = spi_get_drvdata(spi);
521 return memdrv->remove(mem);
526 static void spi_mem_shutdown(struct spi_device *spi)
528 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
529 struct spi_mem *mem = spi_get_drvdata(spi);
531 if (memdrv->shutdown)
532 memdrv->shutdown(mem);
536 * spi_mem_driver_register_with_owner() - Register a SPI memory driver
537 * @memdrv: the SPI memory driver to register
538 * @owner: the owner of this driver
540 * Registers a SPI memory driver.
542 * Return: 0 in case of success, a negative error core otherwise.
545 int spi_mem_driver_register_with_owner(struct spi_mem_driver *memdrv,
546 struct module *owner)
548 memdrv->spidrv.probe = spi_mem_probe;
549 memdrv->spidrv.remove = spi_mem_remove;
550 memdrv->spidrv.shutdown = spi_mem_shutdown;
552 return __spi_register_driver(owner, &memdrv->spidrv);
554 EXPORT_SYMBOL_GPL(spi_mem_driver_register_with_owner);
557 * spi_mem_driver_unregister_with_owner() - Unregister a SPI memory driver
558 * @memdrv: the SPI memory driver to unregister
560 * Unregisters a SPI memory driver.
562 void spi_mem_driver_unregister(struct spi_mem_driver *memdrv)
564 spi_unregister_driver(&memdrv->spidrv);
566 EXPORT_SYMBOL_GPL(spi_mem_driver_unregister);
567 #endif /* __UBOOT__ */