summaryrefslogtreecommitdiffstats
path: root/drivers/spi/spi-coldfire-qspi.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/spi/spi-coldfire-qspi.c')
-rw-r--r--drivers/spi/spi-coldfire-qspi.c513
1 files changed, 513 insertions, 0 deletions
diff --git a/drivers/spi/spi-coldfire-qspi.c b/drivers/spi/spi-coldfire-qspi.c
new file mode 100644
index 0000000000..b341b6908d
--- /dev/null
+++ b/drivers/spi/spi-coldfire-qspi.c
@@ -0,0 +1,513 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Freescale/Motorola Coldfire Queued SPI driver
+ *
+ * Copyright 2010 Steven King <sfking@fdwdc.com>
+*/
+
+#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_controller_get_devdata(spi->controller);
+ bool cs_high = spi->mode & SPI_CS_HIGH;
+
+ if (enable)
+ mcfqspi_cs_select(mcfqspi, spi_get_chipselect(spi, 0), cs_high);
+ else
+ mcfqspi_cs_deselect(mcfqspi, spi_get_chipselect(spi, 0), cs_high);
+}
+
+static int mcfqspi_transfer_one(struct spi_controller *host,
+ struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct mcfqspi *mcfqspi = spi_controller_get_devdata(host);
+ 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_controller_get_devdata(spi->controller),
+ spi_get_chipselect(spi, 0), 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_get_chipselect(spi, 0),
+ (MCFQSPI_BUSCLK / mcfqspi_qmr_baud(spi->max_speed_hz))
+ / 1000);
+
+ return 0;
+}
+
+static int mcfqspi_probe(struct platform_device *pdev)
+{
+ struct spi_controller *host;
+ struct mcfqspi *mcfqspi;
+ 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;
+ }
+
+ host = spi_alloc_host(&pdev->dev, sizeof(*mcfqspi));
+ if (host == NULL) {
+ dev_dbg(&pdev->dev, "spi_alloc_host failed\n");
+ return -ENOMEM;
+ }
+
+ mcfqspi = spi_controller_get_devdata(host);
+
+ mcfqspi->iobase = devm_platform_ioremap_resource(pdev, 0);
+ 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_enabled(&pdev->dev, "qspi_clk");
+ if (IS_ERR(mcfqspi->clk)) {
+ dev_dbg(&pdev->dev, "clk_get failed\n");
+ status = PTR_ERR(mcfqspi->clk);
+ goto fail0;
+ }
+
+ host->bus_num = pdata->bus_num;
+ host->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 fail0;
+ }
+
+ init_waitqueue_head(&mcfqspi->waitq);
+
+ host->mode_bits = SPI_CS_HIGH | SPI_CPOL | SPI_CPHA;
+ host->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 16);
+ host->setup = mcfqspi_setup;
+ host->set_cs = mcfqspi_set_cs;
+ host->transfer_one = mcfqspi_transfer_one;
+ host->auto_runtime_pm = true;
+
+ platform_set_drvdata(pdev, host);
+ pm_runtime_enable(&pdev->dev);
+
+ status = devm_spi_register_controller(&pdev->dev, host);
+ if (status) {
+ dev_dbg(&pdev->dev, "devm_spi_register_controller failed\n");
+ goto fail1;
+ }
+
+ dev_info(&pdev->dev, "Coldfire QSPI bus driver\n");
+
+ return 0;
+
+fail1:
+ pm_runtime_disable(&pdev->dev);
+ mcfqspi_cs_teardown(mcfqspi);
+fail0:
+ spi_controller_put(host);
+
+ dev_dbg(&pdev->dev, "Coldfire QSPI probe failed\n");
+
+ return status;
+}
+
+static void mcfqspi_remove(struct platform_device *pdev)
+{
+ struct spi_controller *host = platform_get_drvdata(pdev);
+ struct mcfqspi *mcfqspi = spi_controller_get_devdata(host);
+
+ 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);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mcfqspi_suspend(struct device *dev)
+{
+ struct spi_controller *host = dev_get_drvdata(dev);
+ struct mcfqspi *mcfqspi = spi_controller_get_devdata(host);
+ int ret;
+
+ ret = spi_controller_suspend(host);
+ if (ret)
+ return ret;
+
+ clk_disable(mcfqspi->clk);
+
+ return 0;
+}
+
+static int mcfqspi_resume(struct device *dev)
+{
+ struct spi_controller *host = dev_get_drvdata(dev);
+ struct mcfqspi *mcfqspi = spi_controller_get_devdata(host);
+
+ clk_enable(mcfqspi->clk);
+
+ return spi_controller_resume(host);
+}
+#endif
+
+#ifdef CONFIG_PM
+static int mcfqspi_runtime_suspend(struct device *dev)
+{
+ struct spi_controller *host = dev_get_drvdata(dev);
+ struct mcfqspi *mcfqspi = spi_controller_get_devdata(host);
+
+ clk_disable(mcfqspi->clk);
+
+ return 0;
+}
+
+static int mcfqspi_runtime_resume(struct device *dev)
+{
+ struct spi_controller *host = dev_get_drvdata(dev);
+ struct mcfqspi *mcfqspi = spi_controller_get_devdata(host);
+
+ 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_new = 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);