1 // SPDX-License-Identifier: GPL-2.0-only
3  * Copyright (C) 2003-2015 Broadcom Corporation
11 #include <linux/spi/spi.h>
14 /* SPI Configuration Register */
25 /* SPI Frequency Divider Register */
28 /* SPI Command Register */
37 /* SPI Status Register */
47 /* SPI Interrupt Enable Register */
55 /* SPI FIFO Threshold Register */
58 /* SPI FIFO Word Count Register */
64 /* SPI Transmit Data FIFO Register */
67 /* SPI Receive Data FIFO Register */
70 /* SPI System Control Register */
84  * SPI can transfer only 28 bytes properly at a time. So split the
91 	void __iomem		*base;		/* spi registers base address */  member
99 	u32			spi_clk;	/* spi clock frequency */
107 	return readl(priv->base + regoff + cs * SPI_CS_OFFSET);  in xlp_spi_reg_read()
113 	writel(val, priv->base + regoff + cs * SPI_CS_OFFSET);  in xlp_spi_reg_write()
119 	writel(val, priv->base + regoff);  in xlp_spi_sysctl_write()
123  * Setup global SPI_SYSCTRL register for all SPI channels.
135 static int xlp_spi_setup(struct spi_device *spi)  in xlp_spi_setup()  argument
141 	xspi = spi_controller_get_devdata(spi->controller);  in xlp_spi_setup()
142 	cs = spi_get_chipselect(spi, 0);  in xlp_spi_setup()
146 	fdiv = DIV_ROUND_UP(xspi->spi_clk, spi->max_speed_hz);  in xlp_spi_setup()
155 	if (spi->mode & SPI_CPHA)  in xlp_spi_setup()
159 	if (spi->mode & SPI_CPOL)  in xlp_spi_setup()
163 	if (!(spi->mode & SPI_CS_HIGH))  in xlp_spi_setup()
167 	if (spi->mode & SPI_LSB_FIRST)  in xlp_spi_setup()
185 	rxfifo_cnt = xlp_spi_reg_read(xspi, xspi->cs, XLP_SPI_FIFO_WCNT);  in xlp_spi_read_rxfifo()
188 		rx_data = xlp_spi_reg_read(xspi, xspi->cs, XLP_SPI_RXDATA_FIFO);  in xlp_spi_read_rxfifo()
190 		nbytes = min(xspi->rx_len, 4);  in xlp_spi_read_rxfifo()
191 		for (i = nbytes - 1; i >= 0; i--, j++)  in xlp_spi_read_rxfifo()
192 			xspi->rx_buf[i] = (rx_data >> (j * 8)) & 0xff;  in xlp_spi_read_rxfifo()
194 		xspi->rx_len -= nbytes;  in xlp_spi_read_rxfifo()
195 		xspi->rx_buf += nbytes;  in xlp_spi_read_rxfifo()
196 		rxfifo_cnt--;  in xlp_spi_read_rxfifo()
205 	txfifo_cnt = xlp_spi_reg_read(xspi, xspi->cs, XLP_SPI_FIFO_WCNT);  in xlp_spi_fill_txfifo()
208 	while (xspi->tx_len && (txfifo_cnt < XLP_SPI_FIFO_SIZE)) {  in xlp_spi_fill_txfifo()
211 		nbytes = min(xspi->tx_len, 4);  in xlp_spi_fill_txfifo()
212 		for (i = nbytes - 1; i >= 0; i--, j++)  in xlp_spi_fill_txfifo()
213 			tx_data |= xspi->tx_buf[i] << (j * 8);  in xlp_spi_fill_txfifo()
215 		xlp_spi_reg_write(xspi, xspi->cs, XLP_SPI_TXDATA_FIFO, tx_data);  in xlp_spi_fill_txfifo()
216 		xspi->tx_len -= nbytes;  in xlp_spi_fill_txfifo()
217 		xspi->tx_buf += nbytes;  in xlp_spi_fill_txfifo()
227 	stat = xlp_spi_reg_read(xspi, xspi->cs, XLP_SPI_STATUS) &  in xlp_spi_interrupt()
233 		if (xspi->tx_len)  in xlp_spi_interrupt()
236 			xspi->txerrors++;  in xlp_spi_interrupt()
240 		if (xspi->rx_len)  in xlp_spi_interrupt()
243 			xspi->rxerrors++;  in xlp_spi_interrupt()
247 	xlp_spi_reg_write(xspi, xspi->cs, XLP_SPI_STATUS, stat);  in xlp_spi_interrupt()
249 		complete(&xspi->done);  in xlp_spi_interrupt()
259 	if (xspi->tx_buf)  in xlp_spi_send_cmd()
261 	if (xspi->rx_buf)  in xlp_spi_send_cmd()
265 	cmd |= ((xfer_len * 8 - 1) << XLP_SPI_XFR_BITCNT_SHIFT);  in xlp_spi_send_cmd()
266 	xlp_spi_reg_write(xspi, xspi->cs, XLP_SPI_CMD, cmd);  in xlp_spi_send_cmd()
276 	xs->tx_buf = tx_buf;  in xlp_spi_xfer_block()
277 	xs->rx_buf = rx_buf;  in xlp_spi_xfer_block()
278 	xs->tx_len = (xs->tx_buf == NULL) ? 0 : xfer_len;  in xlp_spi_xfer_block()
279 	xs->rx_len = (xs->rx_buf == NULL) ? 0 : xfer_len;  in xlp_spi_xfer_block()
280 	xs->txerrors = xs->rxerrors = 0;  in xlp_spi_xfer_block()
283 	if (xs->tx_len)  in xlp_spi_xfer_block()
293 	if (xs->tx_len)  in xlp_spi_xfer_block()
300 	xlp_spi_reg_write(xs, xs->cs, XLP_SPI_INTR_EN, intr_mask);  in xlp_spi_xfer_block()
302 	time_left = wait_for_completion_timeout(&xs->done,  in xlp_spi_xfer_block()
305 	xlp_spi_reg_write(xs, xs->cs, XLP_SPI_INTR_EN, 0x0);  in xlp_spi_xfer_block()
307 		dev_err(&xs->dev, "xfer timedout!\n");  in xlp_spi_xfer_block()
310 	if (xs->txerrors || xs->rxerrors)  in xlp_spi_xfer_block()
311 		dev_err(&xs->dev, "Over/Underflow rx %d tx %d xfer %d!\n",  in xlp_spi_xfer_block()
312 				xs->rxerrors, xs->txerrors, xfer_len);  in xlp_spi_xfer_block()
316 	return -ETIMEDOUT;  in xlp_spi_xfer_block()
325 	tx_buf = t->tx_buf;  in xlp_spi_txrx_bufs()
326 	rx_buf = t->rx_buf;  in xlp_spi_txrx_bufs()
327 	bytesleft = t->len;  in xlp_spi_txrx_bufs()
334 					bytesleft, xs->cmd_cont);  in xlp_spi_txrx_bufs()
337 		bytesleft -= sz;  in xlp_spi_txrx_bufs()
347 					struct spi_device *spi,  in xlp_spi_transfer_one()  argument
353 	xspi->cs = spi_get_chipselect(spi, 0);  in xlp_spi_transfer_one()
354 	xspi->dev = spi->dev;  in xlp_spi_transfer_one()
357 		xspi->cmd_cont = 0;  in xlp_spi_transfer_one()
359 		xspi->cmd_cont = 1;  in xlp_spi_transfer_one()
362 		ret = -EIO;  in xlp_spi_transfer_one()
375 	xspi = devm_kzalloc(&pdev->dev, sizeof(*xspi), GFP_KERNEL);  in xlp_spi_probe()
377 		return -ENOMEM;  in xlp_spi_probe()
379 	xspi->base = devm_platform_ioremap_resource(pdev, 0);  in xlp_spi_probe()
380 	if (IS_ERR(xspi->base))  in xlp_spi_probe()
381 		return PTR_ERR(xspi->base);  in xlp_spi_probe()
386 	err = devm_request_irq(&pdev->dev, irq, xlp_spi_interrupt, 0,  in xlp_spi_probe()
387 			pdev->name, xspi);  in xlp_spi_probe()
389 		dev_err(&pdev->dev, "unable to request irq %d\n", irq);  in xlp_spi_probe()
393 	clk = devm_clk_get(&pdev->dev, NULL);  in xlp_spi_probe()
395 		dev_err(&pdev->dev, "could not get spi clock\n");  in xlp_spi_probe()
399 	xspi->spi_clk = clk_get_rate(clk);  in xlp_spi_probe()
401 	host = spi_alloc_host(&pdev->dev, 0);  in xlp_spi_probe()
403 		dev_err(&pdev->dev, "could not alloc host\n");  in xlp_spi_probe()
404 		return -ENOMEM;  in xlp_spi_probe()
407 	host->bus_num = 0;  in xlp_spi_probe()
408 	host->num_chipselect = XLP_SPI_MAX_CS;  in xlp_spi_probe()
409 	host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;  in xlp_spi_probe()
410 	host->setup = xlp_spi_setup;  in xlp_spi_probe()
411 	host->transfer_one = xlp_spi_transfer_one;  in xlp_spi_probe()
412 	host->dev.of_node = pdev->dev.of_node;  in xlp_spi_probe()
414 	init_completion(&xspi->done);  in xlp_spi_probe()
418 	/* register spi controller */  in xlp_spi_probe()
419 	err = devm_spi_register_controller(&pdev->dev, host);  in xlp_spi_probe()
421 		dev_err(&pdev->dev, "spi register host failed!\n");  in xlp_spi_probe()
441 		.name	= "xlp-spi",
448 MODULE_DESCRIPTION("Netlogic XLP SPI controller driver");