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 bool spi_mem_default_supports_op(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))
169 EXPORT_SYMBOL_GPL(spi_mem_default_supports_op);
172 * spi_mem_supports_op() - Check if a memory device and the controller it is
173 * connected to support a specific memory operation
174 * @slave: the SPI device
175 * @op: the memory operation to check
177 * Some controllers are only supporting Single or Dual IOs, others might only
178 * support specific opcodes, or it can even be that the controller and device
179 * both support Quad IOs but the hardware prevents you from using it because
180 * only 2 IO lines are connected.
182 * This function checks whether a specific operation is supported.
184 * Return: true if @op is supported, false otherwise.
186 bool spi_mem_supports_op(struct spi_slave *slave,
187 const struct spi_mem_op *op)
189 struct udevice *bus = slave->dev->parent;
190 struct dm_spi_ops *ops = spi_get_ops(bus);
192 if (ops->mem_ops && ops->mem_ops->supports_op)
193 return ops->mem_ops->supports_op(slave, op);
195 return spi_mem_default_supports_op(slave, op);
197 EXPORT_SYMBOL_GPL(spi_mem_supports_op);
200 * spi_mem_exec_op() - Execute a memory operation
201 * @slave: the SPI device
202 * @op: the memory operation to execute
204 * Executes a memory operation.
206 * This function first checks that @op is supported and then tries to execute
209 * Return: 0 in case of success, a negative error code otherwise.
211 int spi_mem_exec_op(struct spi_slave *slave, const struct spi_mem_op *op)
213 struct udevice *bus = slave->dev->parent;
214 struct dm_spi_ops *ops = spi_get_ops(bus);
215 unsigned int pos = 0;
216 const u8 *tx_buf = NULL;
223 if (!spi_mem_supports_op(slave, op))
226 ret = spi_claim_bus(slave);
230 if (ops->mem_ops && ops->mem_ops->exec_op) {
233 * Flush the message queue before executing our SPI memory
234 * operation to prevent preemption of regular SPI transfers.
236 spi_flush_queue(ctlr);
238 if (ctlr->auto_runtime_pm) {
239 ret = pm_runtime_get_sync(ctlr->dev.parent);
242 "Failed to power device: %d\n",
248 mutex_lock(&ctlr->bus_lock_mutex);
249 mutex_lock(&ctlr->io_mutex);
251 ret = ops->mem_ops->exec_op(slave, op);
254 mutex_unlock(&ctlr->io_mutex);
255 mutex_unlock(&ctlr->bus_lock_mutex);
257 if (ctlr->auto_runtime_pm)
258 pm_runtime_put(ctlr->dev.parent);
262 * Some controllers only optimize specific paths (typically the
263 * read path) and expect the core to use the regular SPI
264 * interface in other cases.
266 if (!ret || ret != -ENOTSUPP) {
267 spi_release_bus(slave);
273 tmpbufsize = sizeof(op->cmd.opcode) + op->addr.nbytes +
277 * Allocate a buffer to transmit the CMD, ADDR cycles with kmalloc() so
278 * we're guaranteed that this buffer is DMA-able, as required by the
281 tmpbuf = kzalloc(tmpbufsize, GFP_KERNEL | GFP_DMA);
285 spi_message_init(&msg);
287 tmpbuf[0] = op->cmd.opcode;
288 xfers[xferpos].tx_buf = tmpbuf;
289 xfers[xferpos].len = sizeof(op->cmd.opcode);
290 xfers[xferpos].tx_nbits = op->cmd.buswidth;
291 spi_message_add_tail(&xfers[xferpos], &msg);
295 if (op->addr.nbytes) {
298 for (i = 0; i < op->addr.nbytes; i++)
299 tmpbuf[i + 1] = op->addr.val >>
300 (8 * (op->addr.nbytes - i - 1));
302 xfers[xferpos].tx_buf = tmpbuf + 1;
303 xfers[xferpos].len = op->addr.nbytes;
304 xfers[xferpos].tx_nbits = op->addr.buswidth;
305 spi_message_add_tail(&xfers[xferpos], &msg);
307 totalxferlen += op->addr.nbytes;
310 if (op->dummy.nbytes) {
311 memset(tmpbuf + op->addr.nbytes + 1, 0xff, op->dummy.nbytes);
312 xfers[xferpos].tx_buf = tmpbuf + op->addr.nbytes + 1;
313 xfers[xferpos].len = op->dummy.nbytes;
314 xfers[xferpos].tx_nbits = op->dummy.buswidth;
315 spi_message_add_tail(&xfers[xferpos], &msg);
317 totalxferlen += op->dummy.nbytes;
320 if (op->data.nbytes) {
321 if (op->data.dir == SPI_MEM_DATA_IN) {
322 xfers[xferpos].rx_buf = op->data.buf.in;
323 xfers[xferpos].rx_nbits = op->data.buswidth;
325 xfers[xferpos].tx_buf = op->data.buf.out;
326 xfers[xferpos].tx_nbits = op->data.buswidth;
329 xfers[xferpos].len = op->data.nbytes;
330 spi_message_add_tail(&xfers[xferpos], &msg);
332 totalxferlen += op->data.nbytes;
335 ret = spi_sync(slave, &msg);
342 if (msg.actual_length != totalxferlen)
346 if (op->data.nbytes) {
347 if (op->data.dir == SPI_MEM_DATA_IN)
348 rx_buf = op->data.buf.in;
350 tx_buf = op->data.buf.out;
353 op_len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
356 * Avoid using malloc() here so that we can use this code in SPL where
357 * simple malloc may be used. That implementation does not allow free()
358 * so repeated calls to this code can exhaust the space.
360 * The value of op_len is small, since it does not include the actual
361 * data being sent, only the op-code and address. In fact, it should be
362 * possible to just use a small fixed value here instead of op_len.
366 op_buf[pos++] = op->cmd.opcode;
368 if (op->addr.nbytes) {
369 for (i = 0; i < op->addr.nbytes; i++)
370 op_buf[pos + i] = op->addr.val >>
371 (8 * (op->addr.nbytes - i - 1));
373 pos += op->addr.nbytes;
376 if (op->dummy.nbytes)
377 memset(op_buf + pos, 0xff, op->dummy.nbytes);
379 /* 1st transfer: opcode + address + dummy cycles */
380 flag = SPI_XFER_BEGIN;
381 /* Make sure to set END bit if no tx or rx data messages follow */
382 if (!tx_buf && !rx_buf)
383 flag |= SPI_XFER_END;
385 ret = spi_xfer(slave, op_len * 8, op_buf, NULL, flag);
389 /* 2nd transfer: rx or tx data path */
390 if (tx_buf || rx_buf) {
391 ret = spi_xfer(slave, op->data.nbytes * 8, tx_buf,
392 rx_buf, SPI_XFER_END);
397 spi_release_bus(slave);
399 for (i = 0; i < pos; i++)
400 debug("%02x ", op_buf[i]);
402 tx_buf || rx_buf ? op->data.nbytes : 0,
403 tx_buf || rx_buf ? (tx_buf ? "out" : "in") : "-");
404 for (i = 0; i < op->data.nbytes; i++)
405 debug("%02x ", tx_buf ? tx_buf[i] : rx_buf[i]);
406 debug("[ret %d]\n", ret);
410 #endif /* __UBOOT__ */
414 EXPORT_SYMBOL_GPL(spi_mem_exec_op);
417 * spi_mem_adjust_op_size() - Adjust the data size of a SPI mem operation to
418 * match controller limitations
419 * @slave: the SPI device
420 * @op: the operation to adjust
422 * Some controllers have FIFO limitations and must split a data transfer
423 * operation into multiple ones, others require a specific alignment for
424 * optimized accesses. This function allows SPI mem drivers to split a single
425 * operation into multiple sub-operations when required.
427 * Return: a negative error code if the controller can't properly adjust @op,
428 * 0 otherwise. Note that @op->data.nbytes will be updated if @op
429 * can't be handled in a single step.
431 int spi_mem_adjust_op_size(struct spi_slave *slave, struct spi_mem_op *op)
433 struct udevice *bus = slave->dev->parent;
434 struct dm_spi_ops *ops = spi_get_ops(bus);
436 if (ops->mem_ops && ops->mem_ops->adjust_op_size)
437 return ops->mem_ops->adjust_op_size(slave, op);
439 if (!ops->mem_ops || !ops->mem_ops->exec_op) {
442 len = sizeof(op->cmd.opcode) + op->addr.nbytes +
444 if (slave->max_write_size && len > slave->max_write_size)
447 if (op->data.dir == SPI_MEM_DATA_IN) {
448 if (slave->max_read_size)
449 op->data.nbytes = min(op->data.nbytes,
450 slave->max_read_size);
451 } else if (slave->max_write_size) {
452 op->data.nbytes = min(op->data.nbytes,
453 slave->max_write_size - len);
456 if (!op->data.nbytes)
462 EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);
465 static inline struct spi_mem_driver *to_spi_mem_drv(struct device_driver *drv)
467 return container_of(drv, struct spi_mem_driver, spidrv.driver);
470 static int spi_mem_probe(struct spi_device *spi)
472 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
475 mem = devm_kzalloc(&spi->dev, sizeof(*mem), GFP_KERNEL);
480 spi_set_drvdata(spi, mem);
482 return memdrv->probe(mem);
485 static int spi_mem_remove(struct spi_device *spi)
487 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
488 struct spi_mem *mem = spi_get_drvdata(spi);
491 return memdrv->remove(mem);
496 static void spi_mem_shutdown(struct spi_device *spi)
498 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
499 struct spi_mem *mem = spi_get_drvdata(spi);
501 if (memdrv->shutdown)
502 memdrv->shutdown(mem);
506 * spi_mem_driver_register_with_owner() - Register a SPI memory driver
507 * @memdrv: the SPI memory driver to register
508 * @owner: the owner of this driver
510 * Registers a SPI memory driver.
512 * Return: 0 in case of success, a negative error core otherwise.
515 int spi_mem_driver_register_with_owner(struct spi_mem_driver *memdrv,
516 struct module *owner)
518 memdrv->spidrv.probe = spi_mem_probe;
519 memdrv->spidrv.remove = spi_mem_remove;
520 memdrv->spidrv.shutdown = spi_mem_shutdown;
522 return __spi_register_driver(owner, &memdrv->spidrv);
524 EXPORT_SYMBOL_GPL(spi_mem_driver_register_with_owner);
527 * spi_mem_driver_unregister_with_owner() - Unregister a SPI memory driver
528 * @memdrv: the SPI memory driver to unregister
530 * Unregisters a SPI memory driver.
532 void spi_mem_driver_unregister(struct spi_mem_driver *memdrv)
534 spi_unregister_driver(&memdrv->spidrv);
536 EXPORT_SYMBOL_GPL(spi_mem_driver_unregister);
537 #endif /* __UBOOT__ */