Initial import

1 files changed, 529 insertions, 0 deletions

diff --git a/drivers/spi/spi-coldfire-qspi.c b/drivers/spi/spi-coldfire-qspi.c
new file mode 100644
index 000000000..688956ff5
--- /dev/null
+++ b/drivers/spi/spi-coldfire-qspi.c
@@ -0,0 +1,529 @@
+/*
+ * Freescale/Motorola Coldfire Queued SPI driver
+ *
+ * Copyright 2010 Steven King <sfking@fdwdc.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+*/
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/spi/spi.h>
+#include <linux/pm_runtime.h>
+
+#include <asm/coldfire.h>
+#include <asm/mcfsim.h>
+#include <asm/mcfqspi.h>
+
+#define	DRIVER_NAME "mcfqspi"
+
+#define	MCFQSPI_BUSCLK			(MCF_BUSCLK / 2)
+
+#define	MCFQSPI_QMR			0x00
+#define		MCFQSPI_QMR_MSTR	0x8000
+#define		MCFQSPI_QMR_CPOL	0x0200
+#define		MCFQSPI_QMR_CPHA	0x0100
+#define	MCFQSPI_QDLYR			0x04
+#define		MCFQSPI_QDLYR_SPE	0x8000
+#define	MCFQSPI_QWR			0x08
+#define		MCFQSPI_QWR_HALT	0x8000
+#define		MCFQSPI_QWR_WREN	0x4000
+#define		MCFQSPI_QWR_CSIV	0x1000
+#define	MCFQSPI_QIR			0x0C
+#define		MCFQSPI_QIR_WCEFB	0x8000
+#define		MCFQSPI_QIR_ABRTB	0x4000
+#define		MCFQSPI_QIR_ABRTL	0x1000
+#define		MCFQSPI_QIR_WCEFE	0x0800
+#define		MCFQSPI_QIR_ABRTE	0x0400
+#define		MCFQSPI_QIR_SPIFE	0x0100
+#define		MCFQSPI_QIR_WCEF	0x0008
+#define		MCFQSPI_QIR_ABRT	0x0004
+#define		MCFQSPI_QIR_SPIF	0x0001
+#define	MCFQSPI_QAR			0x010
+#define		MCFQSPI_QAR_TXBUF	0x00
+#define		MCFQSPI_QAR_RXBUF	0x10
+#define		MCFQSPI_QAR_CMDBUF	0x20
+#define	MCFQSPI_QDR			0x014
+#define	MCFQSPI_QCR			0x014
+#define		MCFQSPI_QCR_CONT	0x8000
+#define		MCFQSPI_QCR_BITSE	0x4000
+#define		MCFQSPI_QCR_DT		0x2000
+
+struct mcfqspi {
+	void __iomem *iobase;
+	int irq;
+	struct clk *clk;
+	struct mcfqspi_cs_control *cs_control;
+
+	wait_queue_head_t waitq;
+};
+
+static void mcfqspi_wr_qmr(struct mcfqspi *mcfqspi, u16 val)
+{
+	writew(val, mcfqspi->iobase + MCFQSPI_QMR);
+}
+
+static void mcfqspi_wr_qdlyr(struct mcfqspi *mcfqspi, u16 val)
+{
+	writew(val, mcfqspi->iobase + MCFQSPI_QDLYR);
+}
+
+static u16 mcfqspi_rd_qdlyr(struct mcfqspi *mcfqspi)
+{
+	return readw(mcfqspi->iobase + MCFQSPI_QDLYR);
+}
+
+static void mcfqspi_wr_qwr(struct mcfqspi *mcfqspi, u16 val)
+{
+	writew(val, mcfqspi->iobase + MCFQSPI_QWR);
+}
+
+static void mcfqspi_wr_qir(struct mcfqspi *mcfqspi, u16 val)
+{
+	writew(val, mcfqspi->iobase + MCFQSPI_QIR);
+}
+
+static void mcfqspi_wr_qar(struct mcfqspi *mcfqspi, u16 val)
+{
+	writew(val, mcfqspi->iobase + MCFQSPI_QAR);
+}
+
+static void mcfqspi_wr_qdr(struct mcfqspi *mcfqspi, u16 val)
+{
+	writew(val, mcfqspi->iobase + MCFQSPI_QDR);
+}
+
+static u16 mcfqspi_rd_qdr(struct mcfqspi *mcfqspi)
+{
+	return readw(mcfqspi->iobase + MCFQSPI_QDR);
+}
+
+static void mcfqspi_cs_select(struct mcfqspi *mcfqspi, u8 chip_select,
+			    bool cs_high)
+{
+	mcfqspi->cs_control->select(mcfqspi->cs_control, chip_select, cs_high);
+}
+
+static void mcfqspi_cs_deselect(struct mcfqspi *mcfqspi, u8 chip_select,
+				bool cs_high)
+{
+	mcfqspi->cs_control->deselect(mcfqspi->cs_control, chip_select, cs_high);
+}
+
+static int mcfqspi_cs_setup(struct mcfqspi *mcfqspi)
+{
+	return (mcfqspi->cs_control->setup) ?
+		mcfqspi->cs_control->setup(mcfqspi->cs_control) : 0;
+}
+
+static void mcfqspi_cs_teardown(struct mcfqspi *mcfqspi)
+{
+	if (mcfqspi->cs_control->teardown)
+		mcfqspi->cs_control->teardown(mcfqspi->cs_control);
+}
+
+static u8 mcfqspi_qmr_baud(u32 speed_hz)
+{
+	return clamp((MCFQSPI_BUSCLK + speed_hz - 1) / speed_hz, 2u, 255u);
+}
+
+static bool mcfqspi_qdlyr_spe(struct mcfqspi *mcfqspi)
+{
+	return mcfqspi_rd_qdlyr(mcfqspi) & MCFQSPI_QDLYR_SPE;
+}
+
+static irqreturn_t mcfqspi_irq_handler(int this_irq, void *dev_id)
+{
+	struct mcfqspi *mcfqspi = dev_id;
+
+	/* clear interrupt */
+	mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE | MCFQSPI_QIR_SPIF);
+	wake_up(&mcfqspi->waitq);
+
+	return IRQ_HANDLED;
+}
+
+static void mcfqspi_transfer_msg8(struct mcfqspi *mcfqspi, unsigned count,
+				  const u8 *txbuf, u8 *rxbuf)
+{
+	unsigned i, n, offset = 0;
+
+	n = min(count, 16u);
+
+	mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
+	for (i = 0; i < n; ++i)
+		mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
+
+	mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
+	if (txbuf)
+		for (i = 0; i < n; ++i)
+			mcfqspi_wr_qdr(mcfqspi, *txbuf++);
+	else
+		for (i = 0; i < count; ++i)
+			mcfqspi_wr_qdr(mcfqspi, 0);
+
+	count -= n;
+	if (count) {
+		u16 qwr = 0xf08;
+		mcfqspi_wr_qwr(mcfqspi, 0x700);
+		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+
+		do {
+			wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
+			mcfqspi_wr_qwr(mcfqspi, qwr);
+			mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+			if (rxbuf) {
+				mcfqspi_wr_qar(mcfqspi,
+					       MCFQSPI_QAR_RXBUF + offset);
+				for (i = 0; i < 8; ++i)
+					*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
+			}
+			n = min(count, 8u);
+			if (txbuf) {
+				mcfqspi_wr_qar(mcfqspi,
+					       MCFQSPI_QAR_TXBUF + offset);
+				for (i = 0; i < n; ++i)
+					mcfqspi_wr_qdr(mcfqspi, *txbuf++);
+			}
+			qwr = (offset ? 0x808 : 0) + ((n - 1) << 8);
+			offset ^= 8;
+			count -= n;
+		} while (count);
+		wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
+		mcfqspi_wr_qwr(mcfqspi, qwr);
+		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+		if (rxbuf) {
+			mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
+			for (i = 0; i < 8; ++i)
+				*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
+			offset ^= 8;
+		}
+	} else {
+		mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
+		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+	}
+	wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
+	if (rxbuf) {
+		mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
+		for (i = 0; i < n; ++i)
+			*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
+	}
+}
+
+static void mcfqspi_transfer_msg16(struct mcfqspi *mcfqspi, unsigned count,
+				   const u16 *txbuf, u16 *rxbuf)
+{
+	unsigned i, n, offset = 0;
+
+	n = min(count, 16u);
+
+	mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
+	for (i = 0; i < n; ++i)
+		mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
+
+	mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
+	if (txbuf)
+		for (i = 0; i < n; ++i)
+			mcfqspi_wr_qdr(mcfqspi, *txbuf++);
+	else
+		for (i = 0; i < count; ++i)
+			mcfqspi_wr_qdr(mcfqspi, 0);
+
+	count -= n;
+	if (count) {
+		u16 qwr = 0xf08;
+		mcfqspi_wr_qwr(mcfqspi, 0x700);
+		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+
+		do {
+			wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
+			mcfqspi_wr_qwr(mcfqspi, qwr);
+			mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+			if (rxbuf) {
+				mcfqspi_wr_qar(mcfqspi,
+					       MCFQSPI_QAR_RXBUF + offset);
+				for (i = 0; i < 8; ++i)
+					*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
+			}
+			n = min(count, 8u);
+			if (txbuf) {
+				mcfqspi_wr_qar(mcfqspi,
+					       MCFQSPI_QAR_TXBUF + offset);
+				for (i = 0; i < n; ++i)
+					mcfqspi_wr_qdr(mcfqspi, *txbuf++);
+			}
+			qwr = (offset ? 0x808 : 0x000) + ((n - 1) << 8);
+			offset ^= 8;
+			count -= n;
+		} while (count);
+		wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
+		mcfqspi_wr_qwr(mcfqspi, qwr);
+		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+		if (rxbuf) {
+			mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
+			for (i = 0; i < 8; ++i)
+				*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
+			offset ^= 8;
+		}
+	} else {
+		mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
+		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+	}
+	wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
+	if (rxbuf) {
+		mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
+		for (i = 0; i < n; ++i)
+			*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
+	}
+}
+
+static void mcfqspi_set_cs(struct spi_device *spi, bool enable)
+{
+	struct mcfqspi *mcfqspi = spi_master_get_devdata(spi->master);
+	bool cs_high = spi->mode & SPI_CS_HIGH;
+
+	if (enable)
+		mcfqspi_cs_select(mcfqspi, spi->chip_select, cs_high);
+	else
+		mcfqspi_cs_deselect(mcfqspi, spi->chip_select, cs_high);
+}
+
+static int mcfqspi_transfer_one(struct spi_master *master,
+				struct spi_device *spi,
+				struct spi_transfer *t)
+{
+	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
+	u16 qmr = MCFQSPI_QMR_MSTR;
+
+	qmr |= t->bits_per_word << 10;
+	if (spi->mode & SPI_CPHA)
+		qmr |= MCFQSPI_QMR_CPHA;
+	if (spi->mode & SPI_CPOL)
+		qmr |= MCFQSPI_QMR_CPOL;
+	qmr |= mcfqspi_qmr_baud(t->speed_hz);
+	mcfqspi_wr_qmr(mcfqspi, qmr);
+
+	mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE);
+	if (t->bits_per_word == 8)
+		mcfqspi_transfer_msg8(mcfqspi, t->len, t->tx_buf, t->rx_buf);
+	else
+		mcfqspi_transfer_msg16(mcfqspi, t->len / 2, t->tx_buf,
+				       t->rx_buf);
+	mcfqspi_wr_qir(mcfqspi, 0);
+
+	return 0;
+}
+
+static int mcfqspi_setup(struct spi_device *spi)
+{
+	mcfqspi_cs_deselect(spi_master_get_devdata(spi->master),
+			    spi->chip_select, spi->mode & SPI_CS_HIGH);
+
+	dev_dbg(&spi->dev,
+			"bits per word %d, chip select %d, speed %d KHz\n",
+			spi->bits_per_word, spi->chip_select,
+			(MCFQSPI_BUSCLK / mcfqspi_qmr_baud(spi->max_speed_hz))
+			/ 1000);
+
+	return 0;
+}
+
+static int mcfqspi_probe(struct platform_device *pdev)
+{
+	struct spi_master *master;
+	struct mcfqspi *mcfqspi;
+	struct resource *res;
+	struct mcfqspi_platform_data *pdata;
+	int status;
+
+	pdata = dev_get_platdata(&pdev->dev);
+	if (!pdata) {
+		dev_dbg(&pdev->dev, "platform data is missing\n");
+		return -ENOENT;
+	}
+
+	if (!pdata->cs_control) {
+		dev_dbg(&pdev->dev, "pdata->cs_control is NULL\n");
+		return -EINVAL;
+	}
+
+	master = spi_alloc_master(&pdev->dev, sizeof(*mcfqspi));
+	if (master == NULL) {
+		dev_dbg(&pdev->dev, "spi_alloc_master failed\n");
+		return -ENOMEM;
+	}
+
+	mcfqspi = spi_master_get_devdata(master);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mcfqspi->iobase = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(mcfqspi->iobase)) {
+		status = PTR_ERR(mcfqspi->iobase);
+		goto fail0;
+	}
+
+	mcfqspi->irq = platform_get_irq(pdev, 0);
+	if (mcfqspi->irq < 0) {
+		dev_dbg(&pdev->dev, "platform_get_irq failed\n");
+		status = -ENXIO;
+		goto fail0;
+	}
+
+	status = devm_request_irq(&pdev->dev, mcfqspi->irq, mcfqspi_irq_handler,
+				0, pdev->name, mcfqspi);
+	if (status) {
+		dev_dbg(&pdev->dev, "request_irq failed\n");
+		goto fail0;
+	}
+
+	mcfqspi->clk = devm_clk_get(&pdev->dev, "qspi_clk");
+	if (IS_ERR(mcfqspi->clk)) {
+		dev_dbg(&pdev->dev, "clk_get failed\n");
+		status = PTR_ERR(mcfqspi->clk);
+		goto fail0;
+	}
+	clk_enable(mcfqspi->clk);
+
+	master->bus_num = pdata->bus_num;
+	master->num_chipselect = pdata->num_chipselect;
+
+	mcfqspi->cs_control = pdata->cs_control;
+	status = mcfqspi_cs_setup(mcfqspi);
+	if (status) {
+		dev_dbg(&pdev->dev, "error initializing cs_control\n");
+		goto fail1;
+	}
+
+	init_waitqueue_head(&mcfqspi->waitq);
+
+	master->mode_bits = SPI_CS_HIGH | SPI_CPOL | SPI_CPHA;
+	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 16);
+	master->setup = mcfqspi_setup;
+	master->set_cs = mcfqspi_set_cs;
+	master->transfer_one = mcfqspi_transfer_one;
+	master->auto_runtime_pm = true;
+
+	platform_set_drvdata(pdev, master);
+
+	status = devm_spi_register_master(&pdev->dev, master);
+	if (status) {
+		dev_dbg(&pdev->dev, "spi_register_master failed\n");
+		goto fail2;
+	}
+	pm_runtime_enable(&pdev->dev);
+
+	dev_info(&pdev->dev, "Coldfire QSPI bus driver\n");
+
+	return 0;
+
+fail2:
+	mcfqspi_cs_teardown(mcfqspi);
+fail1:
+	clk_disable(mcfqspi->clk);
+fail0:
+	spi_master_put(master);
+
+	dev_dbg(&pdev->dev, "Coldfire QSPI probe failed\n");
+
+	return status;
+}
+
+static int mcfqspi_remove(struct platform_device *pdev)
+{
+	struct spi_master *master = platform_get_drvdata(pdev);
+	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
+
+	pm_runtime_disable(&pdev->dev);
+	/* disable the hardware (set the baud rate to 0) */
+	mcfqspi_wr_qmr(mcfqspi, MCFQSPI_QMR_MSTR);
+
+	mcfqspi_cs_teardown(mcfqspi);
+	clk_disable(mcfqspi->clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mcfqspi_suspend(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
+	int ret;
+
+	ret = spi_master_suspend(master);
+	if (ret)
+		return ret;
+
+	clk_disable(mcfqspi->clk);
+
+	return 0;
+}
+
+static int mcfqspi_resume(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
+
+	clk_enable(mcfqspi->clk);
+
+	return spi_master_resume(master);
+}
+#endif
+
+#ifdef CONFIG_PM
+static int mcfqspi_runtime_suspend(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
+
+	clk_disable(mcfqspi->clk);
+
+	return 0;
+}
+
+static int mcfqspi_runtime_resume(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
+
+	clk_enable(mcfqspi->clk);
+
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops mcfqspi_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(mcfqspi_suspend, mcfqspi_resume)
+	SET_RUNTIME_PM_OPS(mcfqspi_runtime_suspend, mcfqspi_runtime_resume,
+			NULL)
+};
+
+static struct platform_driver mcfqspi_driver = {
+	.driver.name	= DRIVER_NAME,
+	.driver.owner	= THIS_MODULE,
+	.driver.pm	= &mcfqspi_pm,
+	.probe		= mcfqspi_probe,
+	.remove		= mcfqspi_remove,
+};
+module_platform_driver(mcfqspi_driver);
+
+MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
+MODULE_DESCRIPTION("Coldfire QSPI Controller Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRIVER_NAME);