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))
167 if (op->cmd.dtr || op->addr.dtr || op->dummy.dtr || op->data.dtr)
172 EXPORT_SYMBOL_GPL(spi_mem_default_supports_op);
175 * spi_mem_supports_op() - Check if a memory device and the controller it is
176 * connected to support a specific memory operation
177 * @slave: the SPI device
178 * @op: the memory operation to check
180 * Some controllers are only supporting Single or Dual IOs, others might only
181 * support specific opcodes, or it can even be that the controller and device
182 * both support Quad IOs but the hardware prevents you from using it because
183 * only 2 IO lines are connected.
185 * This function checks whether a specific operation is supported.
187 * Return: true if @op is supported, false otherwise.
189 bool spi_mem_supports_op(struct spi_slave *slave,
190 const struct spi_mem_op *op)
192 struct udevice *bus = slave->dev->parent;
193 struct dm_spi_ops *ops = spi_get_ops(bus);
195 if (ops->mem_ops && ops->mem_ops->supports_op)
196 return ops->mem_ops->supports_op(slave, op);
198 return spi_mem_default_supports_op(slave, op);
200 EXPORT_SYMBOL_GPL(spi_mem_supports_op);
203 * spi_mem_exec_op() - Execute a memory operation
204 * @slave: the SPI device
205 * @op: the memory operation to execute
207 * Executes a memory operation.
209 * This function first checks that @op is supported and then tries to execute
212 * Return: 0 in case of success, a negative error code otherwise.
214 int spi_mem_exec_op(struct spi_slave *slave, const struct spi_mem_op *op)
216 struct udevice *bus = slave->dev->parent;
217 struct dm_spi_ops *ops = spi_get_ops(bus);
218 unsigned int pos = 0;
219 const u8 *tx_buf = NULL;
226 if (!spi_mem_supports_op(slave, op))
229 ret = spi_claim_bus(slave);
233 if (ops->mem_ops && ops->mem_ops->exec_op) {
236 * Flush the message queue before executing our SPI memory
237 * operation to prevent preemption of regular SPI transfers.
239 spi_flush_queue(ctlr);
241 if (ctlr->auto_runtime_pm) {
242 ret = pm_runtime_get_sync(ctlr->dev.parent);
245 "Failed to power device: %d\n",
251 mutex_lock(&ctlr->bus_lock_mutex);
252 mutex_lock(&ctlr->io_mutex);
254 ret = ops->mem_ops->exec_op(slave, op);
257 mutex_unlock(&ctlr->io_mutex);
258 mutex_unlock(&ctlr->bus_lock_mutex);
260 if (ctlr->auto_runtime_pm)
261 pm_runtime_put(ctlr->dev.parent);
265 * Some controllers only optimize specific paths (typically the
266 * read path) and expect the core to use the regular SPI
267 * interface in other cases.
269 if (!ret || ret != -ENOTSUPP) {
270 spi_release_bus(slave);
276 tmpbufsize = sizeof(op->cmd.opcode) + op->addr.nbytes +
280 * Allocate a buffer to transmit the CMD, ADDR cycles with kmalloc() so
281 * we're guaranteed that this buffer is DMA-able, as required by the
284 tmpbuf = kzalloc(tmpbufsize, GFP_KERNEL | GFP_DMA);
288 spi_message_init(&msg);
290 tmpbuf[0] = op->cmd.opcode;
291 xfers[xferpos].tx_buf = tmpbuf;
292 xfers[xferpos].len = sizeof(op->cmd.opcode);
293 xfers[xferpos].tx_nbits = op->cmd.buswidth;
294 spi_message_add_tail(&xfers[xferpos], &msg);
298 if (op->addr.nbytes) {
301 for (i = 0; i < op->addr.nbytes; i++)
302 tmpbuf[i + 1] = op->addr.val >>
303 (8 * (op->addr.nbytes - i - 1));
305 xfers[xferpos].tx_buf = tmpbuf + 1;
306 xfers[xferpos].len = op->addr.nbytes;
307 xfers[xferpos].tx_nbits = op->addr.buswidth;
308 spi_message_add_tail(&xfers[xferpos], &msg);
310 totalxferlen += op->addr.nbytes;
313 if (op->dummy.nbytes) {
314 memset(tmpbuf + op->addr.nbytes + 1, 0xff, op->dummy.nbytes);
315 xfers[xferpos].tx_buf = tmpbuf + op->addr.nbytes + 1;
316 xfers[xferpos].len = op->dummy.nbytes;
317 xfers[xferpos].tx_nbits = op->dummy.buswidth;
318 spi_message_add_tail(&xfers[xferpos], &msg);
320 totalxferlen += op->dummy.nbytes;
323 if (op->data.nbytes) {
324 if (op->data.dir == SPI_MEM_DATA_IN) {
325 xfers[xferpos].rx_buf = op->data.buf.in;
326 xfers[xferpos].rx_nbits = op->data.buswidth;
328 xfers[xferpos].tx_buf = op->data.buf.out;
329 xfers[xferpos].tx_nbits = op->data.buswidth;
332 xfers[xferpos].len = op->data.nbytes;
333 spi_message_add_tail(&xfers[xferpos], &msg);
335 totalxferlen += op->data.nbytes;
338 ret = spi_sync(slave, &msg);
345 if (msg.actual_length != totalxferlen)
349 if (op->data.nbytes) {
350 if (op->data.dir == SPI_MEM_DATA_IN)
351 rx_buf = op->data.buf.in;
353 tx_buf = op->data.buf.out;
356 op_len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
359 * Avoid using malloc() here so that we can use this code in SPL where
360 * simple malloc may be used. That implementation does not allow free()
361 * so repeated calls to this code can exhaust the space.
363 * The value of op_len is small, since it does not include the actual
364 * data being sent, only the op-code and address. In fact, it should be
365 * possible to just use a small fixed value here instead of op_len.
369 op_buf[pos++] = op->cmd.opcode;
371 if (op->addr.nbytes) {
372 for (i = 0; i < op->addr.nbytes; i++)
373 op_buf[pos + i] = op->addr.val >>
374 (8 * (op->addr.nbytes - i - 1));
376 pos += op->addr.nbytes;
379 if (op->dummy.nbytes)
380 memset(op_buf + pos, 0xff, op->dummy.nbytes);
382 /* 1st transfer: opcode + address + dummy cycles */
383 flag = SPI_XFER_BEGIN;
384 /* Make sure to set END bit if no tx or rx data messages follow */
385 if (!tx_buf && !rx_buf)
386 flag |= SPI_XFER_END;
388 ret = spi_xfer(slave, op_len * 8, op_buf, NULL, flag);
392 /* 2nd transfer: rx or tx data path */
393 if (tx_buf || rx_buf) {
394 ret = spi_xfer(slave, op->data.nbytes * 8, tx_buf,
395 rx_buf, SPI_XFER_END);
400 spi_release_bus(slave);
402 for (i = 0; i < pos; i++)
403 debug("%02x ", op_buf[i]);
405 tx_buf || rx_buf ? op->data.nbytes : 0,
406 tx_buf || rx_buf ? (tx_buf ? "out" : "in") : "-");
407 for (i = 0; i < op->data.nbytes; i++)
408 debug("%02x ", tx_buf ? tx_buf[i] : rx_buf[i]);
409 debug("[ret %d]\n", ret);
413 #endif /* __UBOOT__ */
417 EXPORT_SYMBOL_GPL(spi_mem_exec_op);
420 * spi_mem_adjust_op_size() - Adjust the data size of a SPI mem operation to
421 * match controller limitations
422 * @slave: the SPI device
423 * @op: the operation to adjust
425 * Some controllers have FIFO limitations and must split a data transfer
426 * operation into multiple ones, others require a specific alignment for
427 * optimized accesses. This function allows SPI mem drivers to split a single
428 * operation into multiple sub-operations when required.
430 * Return: a negative error code if the controller can't properly adjust @op,
431 * 0 otherwise. Note that @op->data.nbytes will be updated if @op
432 * can't be handled in a single step.
434 int spi_mem_adjust_op_size(struct spi_slave *slave, struct spi_mem_op *op)
436 struct udevice *bus = slave->dev->parent;
437 struct dm_spi_ops *ops = spi_get_ops(bus);
439 if (ops->mem_ops && ops->mem_ops->adjust_op_size)
440 return ops->mem_ops->adjust_op_size(slave, op);
442 if (!ops->mem_ops || !ops->mem_ops->exec_op) {
445 len = sizeof(op->cmd.opcode) + op->addr.nbytes +
447 if (slave->max_write_size && len > slave->max_write_size)
450 if (op->data.dir == SPI_MEM_DATA_IN) {
451 if (slave->max_read_size)
452 op->data.nbytes = min(op->data.nbytes,
453 slave->max_read_size);
454 } else if (slave->max_write_size) {
455 op->data.nbytes = min(op->data.nbytes,
456 slave->max_write_size - len);
459 if (!op->data.nbytes)
465 EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);
468 static inline struct spi_mem_driver *to_spi_mem_drv(struct device_driver *drv)
470 return container_of(drv, struct spi_mem_driver, spidrv.driver);
473 static int spi_mem_probe(struct spi_device *spi)
475 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
478 mem = devm_kzalloc(&spi->dev, sizeof(*mem), GFP_KERNEL);
483 spi_set_drvdata(spi, mem);
485 return memdrv->probe(mem);
488 static int spi_mem_remove(struct spi_device *spi)
490 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
491 struct spi_mem *mem = spi_get_drvdata(spi);
494 return memdrv->remove(mem);
499 static void spi_mem_shutdown(struct spi_device *spi)
501 struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
502 struct spi_mem *mem = spi_get_drvdata(spi);
504 if (memdrv->shutdown)
505 memdrv->shutdown(mem);
509 * spi_mem_driver_register_with_owner() - Register a SPI memory driver
510 * @memdrv: the SPI memory driver to register
511 * @owner: the owner of this driver
513 * Registers a SPI memory driver.
515 * Return: 0 in case of success, a negative error core otherwise.
518 int spi_mem_driver_register_with_owner(struct spi_mem_driver *memdrv,
519 struct module *owner)
521 memdrv->spidrv.probe = spi_mem_probe;
522 memdrv->spidrv.remove = spi_mem_remove;
523 memdrv->spidrv.shutdown = spi_mem_shutdown;
525 return __spi_register_driver(owner, &memdrv->spidrv);
527 EXPORT_SYMBOL_GPL(spi_mem_driver_register_with_owner);
530 * spi_mem_driver_unregister_with_owner() - Unregister a SPI memory driver
531 * @memdrv: the SPI memory driver to unregister
533 * Unregisters a SPI memory driver.
535 void spi_mem_driver_unregister(struct spi_mem_driver *memdrv)
537 spi_unregister_driver(&memdrv->spidrv);
539 EXPORT_SYMBOL_GPL(spi_mem_driver_unregister);
540 #endif /* __UBOOT__ */