Lines Matching +full:spi +full:- +full:sck +full:- +full:cs +full:- +full:delay
1 // SPDX-License-Identifier: GPL-2.0+
3 // Freescale MXS SPI host driver
15 // Based on code from U-Boot bootloader by:
18 // Based on spi-stmp.c, which is:
26 #include <linux/delay.h>
28 #include <linux/dma-mapping.h>
39 #include <linux/spi/spi.h>
40 #include <linux/spi/mxs-spi.h>
41 #include <trace/events/spi.h>
42 #include <linux/dma/mxs-dma.h>
44 #define DRIVER_NAME "mxs-spi"
56 #define TXRX_DEASSERT_CS (1<<1) /* De-assert CS at end of txrx */
61 unsigned int sck; /* Rate requested (vs actual) */ member
67 struct mxs_spi *spi = spi_controller_get_devdata(dev->controller); in mxs_spi_setup_transfer() local
68 struct mxs_ssp *ssp = &spi->ssp; in mxs_spi_setup_transfer()
69 const unsigned int hz = min(dev->max_speed_hz, t->speed_hz); in mxs_spi_setup_transfer()
72 dev_err(&dev->dev, "SPI clock rate of zero not allowed\n"); in mxs_spi_setup_transfer()
73 return -EINVAL; in mxs_spi_setup_transfer()
76 if (hz != spi->sck) { in mxs_spi_setup_transfer()
80 * ssp->clk_rate. Otherwise we would set the rate every transfer in mxs_spi_setup_transfer()
83 spi->sck = hz; in mxs_spi_setup_transfer()
91 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); in mxs_spi_setup_transfer()
95 ((dev->mode & SPI_CPOL) ? BM_SSP_CTRL1_POLARITY : 0) | in mxs_spi_setup_transfer()
96 ((dev->mode & SPI_CPHA) ? BM_SSP_CTRL1_PHASE : 0), in mxs_spi_setup_transfer()
97 ssp->base + HW_SSP_CTRL1(ssp)); in mxs_spi_setup_transfer()
99 writel(0x0, ssp->base + HW_SSP_CMD0); in mxs_spi_setup_transfer()
100 writel(0x0, ssp->base + HW_SSP_CMD1); in mxs_spi_setup_transfer()
105 static u32 mxs_spi_cs_to_reg(unsigned cs) in mxs_spi_cs_to_reg() argument
114 * the datasheet for further details. In SPI mode, they are used to in mxs_spi_cs_to_reg()
115 * toggle the chip-select lines (nCS pins). in mxs_spi_cs_to_reg()
117 if (cs & 1) in mxs_spi_cs_to_reg()
119 if (cs & 2) in mxs_spi_cs_to_reg()
125 static int mxs_ssp_wait(struct mxs_spi *spi, int offset, int mask, bool set) in mxs_ssp_wait() argument
128 struct mxs_ssp *ssp = &spi->ssp; in mxs_ssp_wait()
132 reg = readl_relaxed(ssp->base + offset); in mxs_ssp_wait()
143 return -ETIMEDOUT; in mxs_ssp_wait()
148 struct mxs_spi *spi = param; in mxs_ssp_dma_irq_callback() local
150 complete(&spi->c); in mxs_ssp_dma_irq_callback()
157 dev_err(ssp->dev, "%s[%i] CTRL1=%08x STATUS=%08x\n", in mxs_ssp_irq_handler()
159 readl(ssp->base + HW_SSP_CTRL1(ssp)), in mxs_ssp_irq_handler()
160 readl(ssp->base + HW_SSP_STATUS(ssp))); in mxs_ssp_irq_handler()
164 static int mxs_spi_txrx_dma(struct mxs_spi *spi, in mxs_spi_txrx_dma() argument
168 struct mxs_ssp *ssp = &spi->ssp; in mxs_spi_txrx_dma()
183 return -EINVAL; in mxs_spi_txrx_dma()
187 return -ENOMEM; in mxs_spi_txrx_dma()
189 reinit_completion(&spi->c); in mxs_spi_txrx_dma()
192 ctrl0 = readl(ssp->base + HW_SSP_CTRL0); in mxs_spi_txrx_dma()
206 * De-assert CS on last segment if flag is set (i.e., no more in mxs_spi_txrx_dma()
212 if (ssp->devid == IMX23_SSP) { in mxs_spi_txrx_dma()
223 ret = -ENOMEM; in mxs_spi_txrx_dma()
234 ret = dma_map_sg(ssp->dev, &dma_xfer[sg_count].sg, 1, in mxs_spi_txrx_dma()
237 len -= min; in mxs_spi_txrx_dma()
241 desc = dmaengine_prep_slave_sg(ssp->dmach, in mxs_spi_txrx_dma()
243 (ssp->devid == IMX23_SSP) ? 1 : 4, in mxs_spi_txrx_dma()
247 dev_err(ssp->dev, in mxs_spi_txrx_dma()
249 ret = -EINVAL; in mxs_spi_txrx_dma()
253 desc = dmaengine_prep_slave_sg(ssp->dmach, in mxs_spi_txrx_dma()
259 dev_err(ssp->dev, in mxs_spi_txrx_dma()
261 ret = -EINVAL; in mxs_spi_txrx_dma()
270 desc->callback = mxs_ssp_dma_irq_callback; in mxs_spi_txrx_dma()
271 desc->callback_param = spi; in mxs_spi_txrx_dma()
275 dma_async_issue_pending(ssp->dmach); in mxs_spi_txrx_dma()
277 if (!wait_for_completion_timeout(&spi->c, in mxs_spi_txrx_dma()
279 dev_err(ssp->dev, "DMA transfer timeout\n"); in mxs_spi_txrx_dma()
280 ret = -ETIMEDOUT; in mxs_spi_txrx_dma()
281 dmaengine_terminate_all(ssp->dmach); in mxs_spi_txrx_dma()
288 while (--sg_count >= 0) { in mxs_spi_txrx_dma()
290 dma_unmap_sg(ssp->dev, &dma_xfer[sg_count].sg, 1, in mxs_spi_txrx_dma()
299 static int mxs_spi_txrx_pio(struct mxs_spi *spi, in mxs_spi_txrx_pio() argument
303 struct mxs_ssp *ssp = &spi->ssp; in mxs_spi_txrx_pio()
306 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); in mxs_spi_txrx_pio()
308 while (len--) { in mxs_spi_txrx_pio()
311 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); in mxs_spi_txrx_pio()
313 if (ssp->devid == IMX23_SSP) { in mxs_spi_txrx_pio()
315 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); in mxs_spi_txrx_pio()
317 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); in mxs_spi_txrx_pio()
319 writel(1, ssp->base + HW_SSP_XFER_SIZE); in mxs_spi_txrx_pio()
324 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); in mxs_spi_txrx_pio()
327 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); in mxs_spi_txrx_pio()
330 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); in mxs_spi_txrx_pio()
332 if (mxs_ssp_wait(spi, HW_SSP_CTRL0, BM_SSP_CTRL0_RUN, 1)) in mxs_spi_txrx_pio()
333 return -ETIMEDOUT; in mxs_spi_txrx_pio()
336 writel(*buf, ssp->base + HW_SSP_DATA(ssp)); in mxs_spi_txrx_pio()
339 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); in mxs_spi_txrx_pio()
342 if (mxs_ssp_wait(spi, HW_SSP_STATUS(ssp), in mxs_spi_txrx_pio()
344 return -ETIMEDOUT; in mxs_spi_txrx_pio()
346 *buf = (readl(ssp->base + HW_SSP_DATA(ssp)) & 0xff); in mxs_spi_txrx_pio()
349 if (mxs_ssp_wait(spi, HW_SSP_CTRL0, BM_SSP_CTRL0_RUN, 0)) in mxs_spi_txrx_pio()
350 return -ETIMEDOUT; in mxs_spi_txrx_pio()
358 return -ETIMEDOUT; in mxs_spi_txrx_pio()
364 struct mxs_spi *spi = spi_controller_get_devdata(host); in mxs_spi_transfer_one() local
365 struct mxs_ssp *ssp = &spi->ssp; in mxs_spi_transfer_one()
370 /* Program CS register bits here, it will be used for all transfers. */ in mxs_spi_transfer_one()
372 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); in mxs_spi_transfer_one()
373 writel(mxs_spi_cs_to_reg(spi_get_chipselect(m->spi, 0)), in mxs_spi_transfer_one()
374 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); in mxs_spi_transfer_one()
376 list_for_each_entry(t, &m->transfers, transfer_list) { in mxs_spi_transfer_one()
380 status = mxs_spi_setup_transfer(m->spi, t); in mxs_spi_transfer_one()
384 /* De-assert on last transfer, inverted by cs_change flag */ in mxs_spi_transfer_one()
385 flag = (&t->transfer_list == m->transfers.prev) ^ t->cs_change ? in mxs_spi_transfer_one()
397 if (t->len < 32) { in mxs_spi_transfer_one()
399 ssp->base + HW_SSP_CTRL1(ssp) + in mxs_spi_transfer_one()
402 if (t->tx_buf) in mxs_spi_transfer_one()
403 status = mxs_spi_txrx_pio(spi, in mxs_spi_transfer_one()
404 (void *)t->tx_buf, in mxs_spi_transfer_one()
405 t->len, flag | TXRX_WRITE); in mxs_spi_transfer_one()
406 if (t->rx_buf) in mxs_spi_transfer_one()
407 status = mxs_spi_txrx_pio(spi, in mxs_spi_transfer_one()
408 t->rx_buf, t->len, in mxs_spi_transfer_one()
412 ssp->base + HW_SSP_CTRL1(ssp) + in mxs_spi_transfer_one()
415 if (t->tx_buf) in mxs_spi_transfer_one()
416 status = mxs_spi_txrx_dma(spi, in mxs_spi_transfer_one()
417 (void *)t->tx_buf, t->len, in mxs_spi_transfer_one()
419 if (t->rx_buf) in mxs_spi_transfer_one()
420 status = mxs_spi_txrx_dma(spi, in mxs_spi_transfer_one()
421 t->rx_buf, t->len, in mxs_spi_transfer_one()
428 stmp_reset_block(ssp->base); in mxs_spi_transfer_one()
432 m->actual_length += t->len; in mxs_spi_transfer_one()
435 m->status = status; in mxs_spi_transfer_one()
444 struct mxs_spi *spi = spi_controller_get_devdata(host); in mxs_spi_runtime_suspend() local
445 struct mxs_ssp *ssp = &spi->ssp; in mxs_spi_runtime_suspend()
448 clk_disable_unprepare(ssp->clk); in mxs_spi_runtime_suspend()
452 int ret2 = clk_prepare_enable(ssp->clk); in mxs_spi_runtime_suspend()
465 struct mxs_spi *spi = spi_controller_get_devdata(host); in mxs_spi_runtime_resume() local
466 struct mxs_ssp *ssp = &spi->ssp; in mxs_spi_runtime_resume()
473 ret = clk_prepare_enable(ssp->clk); in mxs_spi_runtime_resume()
520 { .compatible = "fsl,imx23-spi", .data = (void *) IMX23_SSP, },
521 { .compatible = "fsl,imx28-spi", .data = (void *) IMX28_SSP, },
529 of_match_device(mxs_spi_dt_ids, &pdev->dev); in mxs_spi_probe()
530 struct device_node *np = pdev->dev.of_node; in mxs_spi_probe()
532 struct mxs_spi *spi; in mxs_spi_probe() local
540 * Default clock speed for the SPI core. 160MHz seems to in mxs_spi_probe()
541 * work reasonably well with most SPI flashes, so use this in mxs_spi_probe()
542 * as a default. Override with "clock-frequency" DT prop. in mxs_spi_probe()
554 clk = devm_clk_get(&pdev->dev, NULL); in mxs_spi_probe()
558 devid = (enum mxs_ssp_id) of_id->data; in mxs_spi_probe()
559 ret = of_property_read_u32(np, "clock-frequency", in mxs_spi_probe()
564 host = spi_alloc_host(&pdev->dev, sizeof(*spi)); in mxs_spi_probe()
566 return -ENOMEM; in mxs_spi_probe()
570 host->transfer_one_message = mxs_spi_transfer_one; in mxs_spi_probe()
571 host->bits_per_word_mask = SPI_BPW_MASK(8); in mxs_spi_probe()
572 host->mode_bits = SPI_CPOL | SPI_CPHA; in mxs_spi_probe()
573 host->num_chipselect = 3; in mxs_spi_probe()
574 host->dev.of_node = np; in mxs_spi_probe()
575 host->flags = SPI_CONTROLLER_HALF_DUPLEX; in mxs_spi_probe()
576 host->auto_runtime_pm = true; in mxs_spi_probe()
578 spi = spi_controller_get_devdata(host); in mxs_spi_probe()
579 ssp = &spi->ssp; in mxs_spi_probe()
580 ssp->dev = &pdev->dev; in mxs_spi_probe()
581 ssp->clk = clk; in mxs_spi_probe()
582 ssp->base = base; in mxs_spi_probe()
583 ssp->devid = devid; in mxs_spi_probe()
585 init_completion(&spi->c); in mxs_spi_probe()
587 ret = devm_request_irq(&pdev->dev, irq_err, mxs_ssp_irq_handler, 0, in mxs_spi_probe()
588 dev_name(&pdev->dev), ssp); in mxs_spi_probe()
592 ssp->dmach = dma_request_chan(&pdev->dev, "rx-tx"); in mxs_spi_probe()
593 if (IS_ERR(ssp->dmach)) { in mxs_spi_probe()
594 dev_err(ssp->dev, "Failed to request DMA\n"); in mxs_spi_probe()
595 ret = PTR_ERR(ssp->dmach); in mxs_spi_probe()
599 pm_runtime_enable(ssp->dev); in mxs_spi_probe()
600 if (!pm_runtime_enabled(ssp->dev)) { in mxs_spi_probe()
601 ret = mxs_spi_runtime_resume(ssp->dev); in mxs_spi_probe()
603 dev_err(ssp->dev, "runtime resume failed\n"); in mxs_spi_probe()
608 ret = pm_runtime_resume_and_get(ssp->dev); in mxs_spi_probe()
610 dev_err(ssp->dev, "runtime_get_sync failed\n"); in mxs_spi_probe()
614 clk_set_rate(ssp->clk, clk_freq); in mxs_spi_probe()
616 ret = stmp_reset_block(ssp->base); in mxs_spi_probe()
620 ret = devm_spi_register_controller(&pdev->dev, host); in mxs_spi_probe()
622 dev_err(&pdev->dev, "Cannot register SPI host, %d\n", ret); in mxs_spi_probe()
626 pm_runtime_put(ssp->dev); in mxs_spi_probe()
631 pm_runtime_put(ssp->dev); in mxs_spi_probe()
633 pm_runtime_disable(ssp->dev); in mxs_spi_probe()
635 dma_release_channel(ssp->dmach); in mxs_spi_probe()
644 struct mxs_spi *spi; in mxs_spi_remove() local
648 spi = spi_controller_get_devdata(host); in mxs_spi_remove()
649 ssp = &spi->ssp; in mxs_spi_remove()
651 pm_runtime_disable(&pdev->dev); in mxs_spi_remove()
652 if (!pm_runtime_status_suspended(&pdev->dev)) in mxs_spi_remove()
653 mxs_spi_runtime_suspend(&pdev->dev); in mxs_spi_remove()
655 dma_release_channel(ssp->dmach); in mxs_spi_remove()
671 MODULE_DESCRIPTION("MXS SPI host driver");
673 MODULE_ALIAS("platform:mxs-spi");