Message-Id: <1391705868-20091-3-git-send-email-iivanov@mm-sol.com>
Date:	Thu,  6 Feb 2014 18:57:48 +0200
From:	"Ivan T. Ivanov" <iivanov@...sol.com>
To:	Mark Brown <broonie@...nel.org>,
	Grant Likely <grant.likely@...aro.org>,
	Rob Herring <robh+dt@...nel.org>
Cc:	"Ivan T. Ivanov" <iivanov@...sol.com>, linux-spi@...r.kernel.org,
	linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org,
	devicetree@...r.kernel.org, Alok Chauhan <alokc@...eaurora.org>,
	Gilad Avidov <gavidov@...eaurora.org>,
	Kiran Gunda <kgunda@...eaurora.org>,
	Sagar Dharia <sdharia@...eaurora.org>
Subject: [PATCH 2/2] spi: Add Qualcomm QUP SPI controller support

From: "Ivan T. Ivanov" <iivanov@...sol.com>

Qualcomm Universal Peripheral (QUP) core is an AHB slave that
provides a common data path (an output FIFO and an input FIFO)
for serial peripheral interface (SPI) mini-core. SPI in master mode
support up to 50MHz, up to four chip selects, and a programmable
data path from 4 bits to 32 bits; MODE0..3 protocols

Signed-off-by: Ivan T. Ivanov <iivanov@...sol.com>
Cc: Alok Chauhan <alokc@...eaurora.org>
Cc: Gilad Avidov <gavidov@...eaurora.org>
Cc: Kiran Gunda <kgunda@...eaurora.org>
Cc: Sagar Dharia <sdharia@...eaurora.org>
---
 drivers/spi/Kconfig   |   14 +
 drivers/spi/Makefile  |    1 +
 drivers/spi/spi-qup.c |  898 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 913 insertions(+)
 create mode 100644 drivers/spi/spi-qup.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index ba9310b..bf8ce6b 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -381,6 +381,20 @@ config SPI_RSPI
 	help
 	  SPI driver for Renesas RSPI blocks.
 
+config SPI_QUP
+	tristate "Qualcomm SPI Support with QUP interface"
+	depends on ARCH_MSM
+	help
+	  Qualcomm Universal Peripheral (QUP) core is an AHB slave that
+	  provides a common data path (an output FIFO and an input FIFO)
+	  for serial peripheral interface (SPI) mini-core. SPI in master
+	  mode support up to 50MHz, up to four chip selects, and a
+	  programmable data path from 4 bits to 32 bits; supports numerous
+	  protocol variants.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called spi_qup.
+
 config SPI_S3C24XX
 	tristate "Samsung S3C24XX series SPI"
 	depends on ARCH_S3C24XX
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 95af48d..e598147 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -59,6 +59,7 @@ spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_PXADMA)	+= spi-pxa2xx-pxadma.o
 spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_DMA)	+= spi-pxa2xx-dma.o
 obj-$(CONFIG_SPI_PXA2XX)		+= spi-pxa2xx-platform.o
 obj-$(CONFIG_SPI_PXA2XX_PCI)		+= spi-pxa2xx-pci.o
+obj-$(CONFIG_SPI_QUP)			+= spi-qup.o
 obj-$(CONFIG_SPI_RSPI)			+= spi-rspi.o
 obj-$(CONFIG_SPI_S3C24XX)		+= spi-s3c24xx-hw.o
 spi-s3c24xx-hw-y			:= spi-s3c24xx.o
diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c
new file mode 100644
index 0000000..5eb5e8f
--- /dev/null
+++ b/drivers/spi/spi-qup.c
@@ -0,0 +1,898 @@
+/*
+ * Copyright (c) 2008-2014, The Linux foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License rev 2 and
+ * only rev 2 as published by the free Software foundation.
+ *
+ * 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/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/spi/spi.h>
+
+#define QUP_CONFIG			0x0000
+#define QUP_STATE			0x0004
+#define QUP_IO_M_MODES			0x0008
+#define QUP_SW_RESET			0x000c
+#define QUP_OPERATIONAL			0x0018
+#define QUP_ERROR_FLAGS			0x001c
+#define QUP_ERROR_FLAGS_EN		0x0020
+#define QUP_OPERATIONAL_MASK		0x0028
+#define QUP_HW_VERSION			0x0030
+#define QUP_MX_OUTPUT_CNT		0x0100
+#define QUP_OUTPUT_FIFO			0x0110
+#define QUP_MX_WRITE_CNT		0x0150
+#define QUP_MX_INPUT_CNT		0x0200
+#define QUP_MX_READ_CNT			0x0208
+#define QUP_INPUT_FIFO			0x0218
+
+#define SPI_CONFIG			0x0300
+#define SPI_IO_CONTROL			0x0304
+#define SPI_ERROR_FLAGS			0x0308
+#define SPI_ERROR_FLAGS_EN		0x030c
+
+/* QUP_CONFIG fields */
+#define QUP_CONFIG_SPI_MODE		(1 << 8)
+#define QUP_CONFIG_NO_INPUT		BIT(7)
+#define QUP_CONFIG_NO_OUTPUT		BIT(6)
+#define QUP_CONFIG_N			0x001f
+
+/* QUP_STATE fields */
+#define QUP_STATE_VALID			BIT(2)
+#define QUP_STATE_RESET			0
+#define QUP_STATE_RUN			1
+#define QUP_STATE_PAUSE			3
+#define QUP_STATE_MASK			3
+#define QUP_STATE_CLEAR			2
+
+#define QUP_HW_VERSION_2_1_1		0x20010001
+
+/* QUP_IO_M_MODES fields */
+#define QUP_IO_M_PACK_EN		BIT(15)
+#define QUP_IO_M_UNPACK_EN		BIT(14)
+#define QUP_IO_M_INPUT_MODE_MASK_SHIFT	12
+#define QUP_IO_M_OUTPUT_MODE_MASK_SHIFT	10
+#define QUP_IO_M_INPUT_MODE_MASK	(3 << QUP_IO_M_INPUT_MODE_MASK_SHIFT)
+#define QUP_IO_M_OUTPUT_MODE_MASK	(3 << QUP_IO_M_OUTPUT_MODE_MASK_SHIFT)
+
+#define QUP_IO_M_OUTPUT_BLOCK_SIZE(x)	(((x) & (0x03 << 0)) >> 0)
+#define QUP_IO_M_OUTPUT_FIFO_SIZE(x)	(((x) & (0x07 << 2)) >> 2)
+#define QUP_IO_M_INPUT_BLOCK_SIZE(x)	(((x) & (0x03 << 5)) >> 5)
+#define QUP_IO_M_INPUT_FIFO_SIZE(x)	(((x) & (0x07 << 7)) >> 7)
+
+#define QUP_IO_M_MODE_FIFO		0
+#define QUP_IO_M_MODE_BLOCK		1
+#define QUP_IO_M_MODE_DMOV		2
+#define QUP_IO_M_MODE_BAM		3
+
+/* QUP_OPERATIONAL fields */
+#define QUP_OP_MAX_INPUT_DONE_FLAG	BIT(11)
+#define QUP_OP_MAX_OUTPUT_DONE_FLAG	BIT(10)
+#define QUP_OP_IN_SERVICE_FLAG		BIT(9)
+#define QUP_OP_OUT_SERVICE_FLAG		BIT(8)
+#define QUP_OP_IN_FIFO_FULL		BIT(7)
+#define QUP_OP_OUT_FIFO_FULL		BIT(6)
+#define QUP_OP_IN_FIFO_NOT_EMPTY	BIT(5)
+#define QUP_OP_OUT_FIFO_NOT_EMPTY	BIT(4)
+
+/* QUP_ERROR_FLAGS and QUP_ERROR_FLAGS_EN fields */
+#define QUP_ERROR_OUTPUT_OVER_RUN	BIT(5)
+#define QUP_ERROR_INPUT_UNDER_RUN	BIT(4)
+#define QUP_ERROR_OUTPUT_UNDER_RUN	BIT(3)
+#define QUP_ERROR_INPUT_OVER_RUN	BIT(2)
+
+/* SPI_CONFIG fields */
+#define SPI_CONFIG_HS_MODE		BIT(10)
+#define SPI_CONFIG_INPUT_FIRST		BIT(9)
+#define SPI_CONFIG_LOOPBACK		BIT(8)
+
+/* SPI_IO_CONTROL fields */
+#define SPI_IO_C_FORCE_CS		BIT(11)
+#define SPI_IO_C_CLK_IDLE_HIGH		BIT(10)
+#define SPI_IO_C_MX_CS_MODE		BIT(8)
+#define SPI_IO_C_CS_N_POLARITY_0	BIT(4)
+#define SPI_IO_C_CS_SELECT(x)		(((x) & 3) << 2)
+#define SPI_IO_C_CS_SELECT_MASK		0x000c
+#define SPI_IO_C_TRISTATE_CS		BIT(1)
+#define SPI_IO_C_NO_TRI_STATE		BIT(0)
+
+/* SPI_ERROR_FLAGS and SPI_ERROR_FLAGS_EN fields */
+#define SPI_ERROR_CLK_OVER_RUN		BIT(1)
+#define SPI_ERROR_CLK_UNDER_RUN		BIT(0)
+
+#define SPI_NUM_CHIPSELECTS		4
+
+/* high speed mode is when bus rate is greater then 26MHz */
+#define SPI_HS_MIN_RATE			26000000
+
+#define SPI_DELAY_THRESHOLD		1
+#define SPI_DELAY_RETRY			10
+
+struct spi_qup_device {
+	int bits_per_word;
+	int chip_select;
+	int speed_hz;
+	u16 mode;
+};
+
+struct spi_qup {
+	void __iomem		*base;
+	struct device		*dev;
+	struct clk		*cclk;	/* core clock */
+	struct clk		*iclk;	/* interface clock */
+	int			irq;
+	u32			max_speed_hz;
+	u32			speed_hz;
+
+	int			in_fifo_sz;
+	int			out_fifo_sz;
+	int			in_blk_sz;
+	int			out_blk_sz;
+
+	struct spi_transfer	*xfer;
+	struct completion	done;
+	int			error;
+	int			bytes_per_word;
+	int			tx_bytes;
+	int			rx_bytes;
+};
+
+
+static inline bool spi_qup_is_valid_state(struct spi_qup *controller)
+{
+	u32 opstate = readl_relaxed(controller->base + QUP_STATE);
+
+	return opstate & QUP_STATE_VALID;
+}
+
+static int spi_qup_set_state(struct spi_qup *controller, u32 state)
+{
+	unsigned long loop = 0;
+	u32 cur_state;
+
+	cur_state = readl_relaxed(controller->base + QUP_STATE);
+	/*
+	 * Per spec: for PAUSE_STATE to RESET_STATE, two writes
+	 * of (b10) are required
+	 */
+	if (((cur_state & QUP_STATE_MASK) == QUP_STATE_PAUSE) &&
+	    (state == QUP_STATE_RESET)) {
+		writel_relaxed(QUP_STATE_CLEAR, controller->base + QUP_STATE);
+		writel_relaxed(QUP_STATE_CLEAR, controller->base + QUP_STATE);
+	} else {
+		cur_state &= ~QUP_STATE_MASK;
+		cur_state |= state;
+		writel_relaxed(cur_state, controller->base + QUP_STATE);
+	}
+
+	while (!spi_qup_is_valid_state(controller)) {
+
+		usleep_range(SPI_DELAY_THRESHOLD, SPI_DELAY_THRESHOLD * 2);
+
+		if (++loop > SPI_DELAY_RETRY)
+			return -EIO;
+	}
+
+	return 0;
+}
+
+static void spi_qup_deassert_cs(struct spi_qup *controller,
+				struct spi_qup_device *chip)
+{
+	u32 iocontol, mask;
+
+	iocontol = readl_relaxed(controller->base + SPI_IO_CONTROL);
+
+	/* Disable auto CS toggle and use manual */
+	iocontol &= ~SPI_IO_C_MX_CS_MODE;
+	iocontol |= SPI_IO_C_FORCE_CS;
+
+	iocontol &= ~SPI_IO_C_CS_SELECT_MASK;
+	iocontol |= SPI_IO_C_CS_SELECT(chip->chip_select);
+
+	mask = SPI_IO_C_CS_N_POLARITY_0 << chip->chip_select;
+
+	if (chip->mode & SPI_CS_HIGH)
+		iocontol &= ~mask;
+	else
+		iocontol |= mask;
+
+	writel_relaxed(iocontol, controller->base + SPI_IO_CONTROL);
+}
+
+static void spi_qup_assert_cs(struct spi_qup *controller,
+			      struct spi_qup_device *chip)
+{
+	u32 iocontol, mask;
+
+	iocontol = readl_relaxed(controller->base + SPI_IO_CONTROL);
+
+	/* Disable auto CS toggle and use manual */
+	iocontol &= ~SPI_IO_C_MX_CS_MODE;
+	iocontol |= SPI_IO_C_FORCE_CS;
+
+	iocontol &= ~SPI_IO_C_CS_SELECT_MASK;
+	iocontol |= SPI_IO_C_CS_SELECT(chip->chip_select);
+
+	mask = SPI_IO_C_CS_N_POLARITY_0 << chip->chip_select;
+
+	if (chip->mode & SPI_CS_HIGH)
+		iocontol |= mask;
+	else
+		iocontol &= ~mask;
+
+	writel_relaxed(iocontol, controller->base + SPI_IO_CONTROL);
+}
+
+static void spi_qup_fifo_read(struct spi_qup *controller,
+			      struct spi_transfer *xfer)
+{
+	u8 *rx_buf = xfer->rx_buf;
+	u32 word, state;
+	int idx, shift;
+
+	while (controller->rx_bytes < xfer->len) {
+
+		state = readl_relaxed(controller->base + QUP_OPERATIONAL);
+		if (0 == (state & QUP_OP_IN_FIFO_NOT_EMPTY))
+			break;
+
+		word = readl_relaxed(controller->base + QUP_INPUT_FIFO);
+
+		for (idx = 0; idx < controller->bytes_per_word &&
+		     controller->rx_bytes < xfer->len; idx++,
+		     controller->rx_bytes++) {
+
+			if (!rx_buf)
+				continue;
+			/*
+			 * The data format depends on bytes_per_word:
+			 *  4 bytes: 0x12345678
+			 *  2 bytes: 0x00001234
+			 *  1 byte : 0x00000012
+			 */
+			shift = BITS_PER_BYTE;
+			shift *= (controller->bytes_per_word - idx - 1);
+			rx_buf[controller->rx_bytes] = word >> shift;
+		}
+	}
+}
+
+static void spi_qup_fifo_write(struct spi_qup *controller,
+			       struct spi_transfer *xfer)
+{
+	const u8 *tx_buf = xfer->tx_buf;
+	u32 word, state, data;
+	int idx;
+
+	while (controller->tx_bytes < xfer->len) {
+
+		state = readl_relaxed(controller->base + QUP_OPERATIONAL);
+		if (state & QUP_OP_OUT_FIFO_FULL)
+			break;
+
+		word = 0;
+		for (idx = 0; idx < controller->bytes_per_word &&
+		     controller->tx_bytes < xfer->len; idx++,
+		     controller->tx_bytes++) {
+
+			if (!tx_buf)
+				continue;
+
+			data = tx_buf[controller->tx_bytes];
+			word |= data << (BITS_PER_BYTE * (3 - idx));
+		}
+
+		writel_relaxed(word, controller->base + QUP_OUTPUT_FIFO);
+	}
+}
+
+static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id)
+{
+	struct spi_qup *controller = dev_id;
+	struct spi_transfer *xfer;
+	u32 opflags, qup_err, spi_err;
+
+	xfer = controller->xfer;
+
+	qup_err = readl_relaxed(controller->base + QUP_ERROR_FLAGS);
+	spi_err = readl_relaxed(controller->base + SPI_ERROR_FLAGS);
+	opflags = readl_relaxed(controller->base + QUP_OPERATIONAL);
+
+	writel_relaxed(qup_err, controller->base + QUP_ERROR_FLAGS);
+	writel_relaxed(spi_err, controller->base + SPI_ERROR_FLAGS);
+	writel_relaxed(opflags, controller->base + QUP_OPERATIONAL);
+
+	if (!xfer)
+		return IRQ_HANDLED;
+
+	if (qup_err) {
+		if (qup_err & QUP_ERROR_OUTPUT_OVER_RUN)
+			dev_warn(controller->dev, "OUTPUT_OVER_RUN\n");
+		if (qup_err & QUP_ERROR_INPUT_UNDER_RUN)
+			dev_warn(controller->dev, "INPUT_UNDER_RUN\n");
+		if (qup_err & QUP_ERROR_OUTPUT_UNDER_RUN)
+			dev_warn(controller->dev, "OUTPUT_UNDER_RUN\n");
+		if (qup_err & QUP_ERROR_INPUT_OVER_RUN)
+			dev_warn(controller->dev, "INPUT_OVER_RUN\n");
+
+		controller->error = -EIO;
+	}
+
+	if (spi_err) {
+		if (spi_err & SPI_ERROR_CLK_OVER_RUN)
+			dev_warn(controller->dev, "CLK_OVER_RUN\n");
+		if (spi_err & SPI_ERROR_CLK_UNDER_RUN)
+			dev_warn(controller->dev, "CLK_UNDER_RUN\n");
+
+		controller->error = -EIO;
+	}
+
+	if (opflags & QUP_OP_IN_SERVICE_FLAG) {
+		writel_relaxed(QUP_OP_IN_SERVICE_FLAG,
+		       controller->base + QUP_OPERATIONAL);
+		spi_qup_fifo_read(controller, xfer);
+	}
+
+	if (opflags & QUP_OP_OUT_SERVICE_FLAG) {
+		writel_relaxed(QUP_OP_OUT_SERVICE_FLAG,
+		       controller->base + QUP_OPERATIONAL);
+		spi_qup_fifo_write(controller, xfer);
+	}
+
+	if (controller->rx_bytes == xfer->len ||
+	    controller->error)
+		complete(&controller->done);
+
+	return IRQ_HANDLED;
+}
+
+static int spi_qup_transfer_do(struct spi_qup *controller,
+			       struct spi_qup_device *chip,
+			       struct spi_transfer *xfer)
+{
+	unsigned long timeout;
+	int ret = -EIO;
+
+	reinit_completion(&controller->done);
+
+	timeout = DIV_ROUND_UP(controller->speed_hz, MSEC_PER_SEC);
+	timeout = DIV_ROUND_UP(xfer->len * 8, timeout);
+	timeout = 100 * msecs_to_jiffies(timeout);
+
+	controller->rx_bytes = 0;
+	controller->tx_bytes = 0;
+	controller->error = 0;
+	controller->xfer = xfer;
+
+	if (spi_qup_set_state(controller, QUP_STATE_RUN)) {
+		dev_warn(controller->dev, "cannot set RUN state\n");
+		goto exit;
+	}
+
+	if (spi_qup_set_state(controller, QUP_STATE_PAUSE)) {
+		dev_warn(controller->dev, "cannot set PAUSE state\n");
+		goto exit;
+	}
+
+	spi_qup_fifo_write(controller, xfer);
+
+	if (spi_qup_set_state(controller, QUP_STATE_RUN)) {
+		dev_warn(controller->dev, "cannot set EXECUTE state\n");
+		goto exit;
+	}
+
+	if (!wait_for_completion_timeout(&controller->done, timeout))
+		ret = -ETIMEDOUT;
+	else
+		ret = controller->error;
+exit:
+	controller->xfer = NULL;
+	controller->error = 0;
+	controller->rx_bytes = 0;
+	controller->tx_bytes = 0;
+	spi_qup_set_state(controller, QUP_STATE_RESET);
+	return ret;
+}
+
+static int spi_qup_setup(struct spi_device *spi)
+{
+	struct spi_qup *controller = spi_master_get_devdata(spi->master);
+	struct spi_qup_device *chip = spi_get_ctldata(spi);
+
+	if (spi->chip_select >= spi->master->num_chipselect) {
+		dev_err(controller->dev, "invalid chip_select %d\n",
+			spi->chip_select);
+		return -EINVAL;
+	}
+
+	if (spi->max_speed_hz > controller->max_speed_hz) {
+		dev_err(controller->dev, "invalid max_speed_hz %d\n",
+			spi->max_speed_hz);
+		return -EINVAL;
+	}
+
+	if (!chip) {
+		/* First setup */
+		chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+		if (!chip) {
+			dev_err(controller->dev, "no memory for chip data\n");
+			return -ENOMEM;
+		}
+
+		spi_set_ctldata(spi, chip);
+	}
+
+	return 0;
+}
+
+static void spi_qup_cleanup(struct spi_device *spi)
+{
+	struct spi_qup_device *chip = spi_get_ctldata(spi);
+
+	if (!chip)
+		return;
+
+	spi_set_ctldata(spi, NULL);
+	kfree(chip);
+}
+
+/* set clock freq, clock ramp, bits per work */
+static int spi_qup_io_setup(struct spi_device *spi,
+			  struct spi_transfer *xfer)
+{
+	struct spi_qup *controller = spi_master_get_devdata(spi->master);
+	struct spi_qup_device *chip = spi_get_ctldata(spi);
+	u32 iocontol, config, iomode, mode;
+	int ret, n_words;
+
+	if (spi->mode & SPI_LOOP && xfer->len > controller->in_fifo_sz) {
+		dev_err(controller->dev, "too big size for loopback %d > %d\n",
+			xfer->len, controller->in_fifo_sz);
+		return -EIO;
+	}
+
+	chip->mode = spi->mode;
+	chip->speed_hz = spi->max_speed_hz;
+	if (xfer->speed_hz)
+		chip->speed_hz = xfer->speed_hz;
+
+	if (controller->speed_hz != chip->speed_hz) {
+		ret = clk_set_rate(controller->cclk, chip->speed_hz);
+		if (ret) {
+			dev_err(controller->dev, "fail to set frequency %d",
+				chip->speed_hz);
+			return -EIO;
+		}
+	}
+
+	controller->speed_hz = chip->speed_hz;
+
+	chip->bits_per_word = spi->bits_per_word;
+	if (xfer->bits_per_word)
+		chip->bits_per_word = xfer->bits_per_word;
+
+	if (chip->bits_per_word <= 8)
+		controller->bytes_per_word = 1;
+	else if (chip->bits_per_word <= 16)
+		controller->bytes_per_word = 2;
+	else
+		controller->bytes_per_word = 4;
+
+	if (controller->bytes_per_word > xfer->len ||
+	    xfer->len % controller->bytes_per_word != 0){
+		/* No partial transfers */
+		dev_err(controller->dev, "invalid len %d for %d bits\n",
+			xfer->len, chip->bits_per_word);
+		return -EIO;
+	}
+
+	n_words = xfer->len / controller->bytes_per_word;
+
+	if (spi_qup_set_state(controller, QUP_STATE_RESET)) {
+		dev_err(controller->dev, "cannot set RESET state\n");
+		return -EIO;
+	}
+
+	if (n_words <= controller->in_fifo_sz) {
+		mode = QUP_IO_M_MODE_FIFO;
+		writel_relaxed(n_words, controller->base + QUP_MX_READ_CNT);
+		writel_relaxed(n_words, controller->base + QUP_MX_WRITE_CNT);
+		/* must be zero for FIFO */
+		writel_relaxed(0, controller->base + QUP_MX_INPUT_CNT);
+		writel_relaxed(0, controller->base + QUP_MX_OUTPUT_CNT);
+	} else {
+		mode = QUP_IO_M_MODE_BLOCK;
+		writel_relaxed(n_words, controller->base + QUP_MX_INPUT_CNT);
+		writel_relaxed(n_words, controller->base + QUP_MX_OUTPUT_CNT);
+		/* must be zero for BLOCK and BAM */
+		writel_relaxed(0, controller->base + QUP_MX_READ_CNT);
+		writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT);
+	}
+
+	iomode = readl_relaxed(controller->base + QUP_IO_M_MODES);
+	/* Set input and output transfer mode */
+	iomode &= ~(QUP_IO_M_INPUT_MODE_MASK | QUP_IO_M_OUTPUT_MODE_MASK);
+	iomode &= ~(QUP_IO_M_PACK_EN | QUP_IO_M_UNPACK_EN);
+	iomode |= (mode << QUP_IO_M_OUTPUT_MODE_MASK_SHIFT);
+	iomode |= (mode << QUP_IO_M_INPUT_MODE_MASK_SHIFT);
+
+	writel_relaxed(iomode, controller->base + QUP_IO_M_MODES);
+
+	config = readl_relaxed(controller->base + SPI_CONFIG);
+
+	if (chip->mode & SPI_LOOP)
+		config |= SPI_CONFIG_LOOPBACK;
+	else
+		config &= ~SPI_CONFIG_LOOPBACK;
+
+	if (chip->mode & SPI_CPHA)
+		config &= ~SPI_CONFIG_INPUT_FIRST;
+	else
+		config |= SPI_CONFIG_INPUT_FIRST;
+
+	/*
+	 * HS_MODE improves signal stability for spi-clk high rates
+	 * but is invalid in loop back mode.
+	 */
+	if ((controller->speed_hz >= SPI_HS_MIN_RATE) &&
+	    !(chip->mode & SPI_LOOP))
+		config |= SPI_CONFIG_HS_MODE;
+	else
+		config &= ~SPI_CONFIG_HS_MODE;
+
+	writel_relaxed(config, controller->base + SPI_CONFIG);
+
+	config = readl_relaxed(controller->base + QUP_CONFIG);
+	config &= ~(QUP_CONFIG_NO_INPUT | QUP_CONFIG_NO_OUTPUT | QUP_CONFIG_N);
+	config |= chip->bits_per_word - 1;
+	config |= QUP_CONFIG_SPI_MODE;
+	writel_relaxed(config, controller->base + QUP_CONFIG);
+
+	iocontol = readl_relaxed(controller->base + SPI_IO_CONTROL);
+
+	/* Disable auto CS toggle */
+	iocontol &= ~SPI_IO_C_MX_CS_MODE;
+
+	if (chip->mode & SPI_CPOL)
+		iocontol |= SPI_IO_C_CLK_IDLE_HIGH;
+	else
+		iocontol &= ~SPI_IO_C_CLK_IDLE_HIGH;
+
+	writel_relaxed(iocontol, controller->base + SPI_IO_CONTROL);
+
+	/*
+	 * TODO: In BAM mode mask INPUT and OUTPUT service flags in
+	 * to prevent IRQs on FIFO status change.
+	 */
+	writel_relaxed(0, controller->base + QUP_OPERATIONAL_MASK);
+
+	return 0;
+}
+
+static int spi_qup_transfer_one(struct spi_master *master,
+				struct spi_message *msg)
+{
+	struct spi_qup *controller = spi_master_get_devdata(master);
+	struct spi_qup_device *chip = spi_get_ctldata(msg->spi);
+	struct spi_transfer *xfer;
+	struct spi_device *spi;
+	unsigned cs_change;
+	int status;
+
+	spi = msg->spi;
+	cs_change = 1;
+	status = 0;
+
+	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+
+		status = spi_qup_io_setup(spi, xfer);
+		if (status)
+			break;
+
+		if (cs_change)
+			spi_qup_assert_cs(controller, chip);
+
+		cs_change = xfer->cs_change;
+
+		/* Do actual transfer */
+		status = spi_qup_transfer_do(controller, chip, xfer);
+		if (status)
+			break;
+
+		msg->actual_length += xfer->len;
+
+		if (xfer->delay_usecs)
+			udelay(xfer->delay_usecs);
+
+		if (cs_change)
+			spi_qup_deassert_cs(controller, chip);
+	}
+
+	if (status || !cs_change)
+		spi_qup_deassert_cs(controller, chip);
+
+	msg->status = status;
+	spi_finalize_current_message(master);
+	return status;
+}
+
+static int spi_qup_probe(struct platform_device *pdev)
+{
+	struct spi_master *master;
+	struct clk *iclk, *cclk;
+	struct spi_qup *controller;
+	struct resource *res;
+	struct device *dev;
+	void __iomem *base;
+	u32 data, max_freq, iomode;
+	int ret, irq, size;
+
+	dev = &pdev->dev;
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	irq = platform_get_irq(pdev, 0);
+
+	if (irq < 0)
+		return irq;
+
+	cclk = devm_clk_get(dev, "core");
+	if (IS_ERR(cclk)) {
+		dev_err(dev, "cannot get core clock\n");
+		return PTR_ERR(cclk);
+	}
+
+	iclk = devm_clk_get(dev, "iface");
+	if (IS_ERR(iclk)) {
+		dev_err(dev, "cannot get iface clock\n");
+		return PTR_ERR(iclk);
+	}
+
+	if (of_property_read_u32(dev->of_node, "spi-max-frequency", &max_freq))
+		max_freq = 19200000;
+
+	if (!max_freq) {
+		dev_err(dev, "invalid clock frequency %d\n", max_freq);
+		return -ENXIO;
+	}
+
+	ret = clk_set_rate(cclk, max_freq);
+	if (ret)
+		dev_warn(dev, "fail to set SPI frequency %d\n", max_freq);
+
+	ret = clk_prepare_enable(cclk);
+	if (ret) {
+		dev_err(dev, "cannot enable core clock\n");
+		return ret;
+	}
+
+	ret = clk_prepare_enable(iclk);
+	if (ret) {
+		clk_disable_unprepare(cclk);
+		dev_err(dev, "cannot enable iface clock\n");
+		return ret;
+	}
+
+	data = readl_relaxed(base + QUP_HW_VERSION);
+
+	if (data < QUP_HW_VERSION_2_1_1) {
+		clk_disable_unprepare(cclk);
+		clk_disable_unprepare(iclk);
+		dev_err(dev, "v.%08x is not supported\n", data);
+		return -ENXIO;
+	}
+
+	master = spi_alloc_master(dev, sizeof(struct spi_qup));
+	if (!master) {
+		clk_disable_unprepare(cclk);
+		clk_disable_unprepare(iclk);
+		dev_err(dev, "cannot allocate master\n");
+		return -ENOMEM;
+	}
+
+	master->bus_num = pdev->id;
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
+	master->num_chipselect = SPI_NUM_CHIPSELECTS;
+	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
+	master->setup = spi_qup_setup;
+	master->cleanup = spi_qup_cleanup;
+	master->transfer_one_message = spi_qup_transfer_one;
+	master->dev.of_node = pdev->dev.of_node;
+	master->auto_runtime_pm = true;
+
+	platform_set_drvdata(pdev, master);
+
+	controller = spi_master_get_devdata(master);
+
+	controller->dev  = dev;
+	controller->base = base;
+	controller->iclk = iclk;
+	controller->cclk = cclk;
+	controller->irq  = irq;
+	controller->max_speed_hz = clk_get_rate(cclk);
+	controller->speed_hz = controller->max_speed_hz;
+
+	init_completion(&controller->done);
+
+	iomode = readl_relaxed(base + QUP_IO_M_MODES);
+
+	size = QUP_IO_M_OUTPUT_BLOCK_SIZE(iomode);
+	if (size)
+		controller->out_blk_sz = size * 16;
+	else
+		controller->out_blk_sz = 4;
+
+	size = QUP_IO_M_INPUT_BLOCK_SIZE(iomode);
+	if (size)
+		controller->in_blk_sz = size * 16;
+	else
+		controller->in_blk_sz = 4;
+
+	size = QUP_IO_M_OUTPUT_FIFO_SIZE(iomode);
+	controller->out_fifo_sz = controller->out_blk_sz * (2 << size);
+
+	size = QUP_IO_M_INPUT_FIFO_SIZE(iomode);
+	controller->in_fifo_sz = controller->in_blk_sz * (2 << size);
+
+	dev_info(dev, "v.%08x IN:block:%d, fifo:%d, OUT:block:%d, fifo:%d\n",
+		 data, controller->in_blk_sz, controller->in_fifo_sz,
+		 controller->out_blk_sz, controller->out_fifo_sz);
+
+	writel_relaxed(1, base + QUP_SW_RESET);
+
+	ret = spi_qup_set_state(controller, QUP_STATE_RESET);
+	if (ret) {
+		dev_err(dev, "cannot set RESET state\n");
+		goto error;
+	}
+
+	writel_relaxed(0, base + QUP_OPERATIONAL);
+	writel_relaxed(0, base + QUP_IO_M_MODES);
+	writel_relaxed(0, base + QUP_OPERATIONAL_MASK);
+	writel_relaxed(SPI_ERROR_CLK_UNDER_RUN | SPI_ERROR_CLK_OVER_RUN,
+		       base + SPI_ERROR_FLAGS_EN);
+
+	writel_relaxed(0, base + SPI_CONFIG);
+	writel_relaxed(SPI_IO_C_NO_TRI_STATE, base + SPI_IO_CONTROL);
+
+	ret = devm_request_irq(dev, irq, spi_qup_qup_irq,
+			       IRQF_TRIGGER_HIGH, pdev->name, controller);
+	if (ret) {
+		dev_err(dev, "cannot request IRQ %d\n", irq);
+		goto error;
+	}
+
+	ret = devm_spi_register_master(dev, master);
+	if (!ret) {
+		pm_runtime_set_autosuspend_delay(dev, MSEC_PER_SEC);
+		pm_runtime_use_autosuspend(dev);
+		pm_runtime_set_active(dev);
+		pm_runtime_enable(dev);
+		return ret;
+	}
+error:
+	clk_disable_unprepare(cclk);
+	clk_disable_unprepare(iclk);
+	spi_master_put(master);
+	return ret;
+}
+
+#ifdef CONFIG_PM_RUNTIME
+static int spi_qup_pm_suspend_runtime(struct device *device)
+{
+	struct spi_master *master = dev_get_drvdata(device);
+	struct spi_qup *controller = spi_master_get_devdata(master);
+
+	disable_irq(controller->irq);
+	clk_disable_unprepare(controller->cclk);
+	clk_disable_unprepare(controller->iclk);
+	dev_dbg(device, "suspend runtime\n");
+	return 0;
+}
+
+static int spi_qup_pm_resume_runtime(struct device *device)
+{
+	struct spi_master *master = dev_get_drvdata(device);
+	struct spi_qup *controller = spi_master_get_devdata(master);
+
+	clk_prepare_enable(controller->cclk);
+	clk_prepare_enable(controller->iclk);
+	enable_irq(controller->irq);
+	dev_dbg(device, "resume runtime\n");
+	return 0;
+}
+#endif /* CONFIG_PM_RUNTIME */
+
+#ifdef CONFIG_PM_SLEEP
+static int spi_qup_suspend(struct device *device)
+{
+	struct spi_master *master = dev_get_drvdata(device);
+	struct spi_qup *controller = spi_master_get_devdata(master);
+	int status;
+
+	status = spi_master_suspend(master);
+	if (!status) {
+		disable_irq(controller->irq);
+		clk_disable_unprepare(controller->cclk);
+		clk_disable_unprepare(controller->iclk);
+	}
+
+	dev_dbg(device, "system suspend %d\n", status);
+	return status;
+}
+
+static int spi_qup_resume(struct device *device)
+{
+	struct spi_master *master = dev_get_drvdata(device);
+	struct spi_qup *controller = spi_master_get_devdata(master);
+	int status;
+
+	clk_prepare_enable(controller->cclk);
+	clk_prepare_enable(controller->iclk);
+
+	status = spi_master_resume(master);
+
+	dev_dbg(device, "system resume %d\n", status);
+	return status;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static int spi_qup_remove(struct platform_device *pdev)
+{
+	struct spi_master *master = dev_get_drvdata(&pdev->dev);
+	struct spi_qup *controller = spi_master_get_devdata(master);
+
+	pm_runtime_get_sync(&pdev->dev);
+
+	clk_disable_unprepare(controller->cclk);
+	clk_disable_unprepare(controller->iclk);
+
+	pm_runtime_put_noidle(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	return 0;
+}
+
+static struct of_device_id spi_qup_dt_match[] = {
+	{ .compatible = "qcom,spi-qup-v2", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, spi_qup_dt_match);
+
+static const struct dev_pm_ops spi_qup_dev_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(spi_qup_suspend, spi_qup_resume)
+	SET_RUNTIME_PM_OPS(spi_qup_pm_suspend_runtime,
+			   spi_qup_pm_resume_runtime,
+			   NULL)
+};
+
+static struct platform_driver spi_qup_driver = {
+	.driver = {
+		.name		= "spi_qup",
+		.owner		= THIS_MODULE,
+		.pm		= &spi_qup_dev_pm_ops,
+		.of_match_table = spi_qup_dt_match,
+	},
+	.probe = spi_qup_probe,
+	.remove = spi_qup_remove,
+};
+module_platform_driver(spi_qup_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION("0.4");
+MODULE_ALIAS("platform:spi_qup");
-- 
1.7.9.5

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