spi: bcm-qspi: Add Broadcom MSPI driver

Master SPI driver for Broadcom settop, iProc SoCs. The driver
is used for devices that use SPI protocol on BRCMSTB, NSP, NS2
SoCs. SoC platform driver call exported porbe(), remove()
and suspend/resume pm_ops implemented in this common driver.
Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: Yendapally Reddy Dhananjaya Reddy
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/Kconfig

@@ -153,6 +153,16 @@ config SPI_BCM63XX_HSSPI
 	  This enables support for the High Speed SPI controller present on
 	  newer Broadcom BCM63XX SoCs.
 
+config SPI_BCM_QSPI
+	tristate "Broadcom BSPI and MSPI controller support"
+	depends on ARCH_BRCMSTB || ARCH_BCM || ARCH_BCM_IPROC || COMPILE_TEST
+	default ARCH_BCM_IPROC
+	help
+	  Enables support for the Broadcom SPI flash and MSPI controller.
+	  Select this option for any one of BRCMSTB, iProc NSP and NS2 SoCs
+	  based platforms. This driver works for both SPI master for spi-nor
+	  flash device as well as MSPI device.
+
 config SPI_BITBANG
 	tristate "Utilities for Bitbanging SPI masters"
 	help

drivers/spi/Makefile

@@ -21,6 +21,7 @@ obj-$(CONFIG_SPI_BCM2835AUX)		+= spi-bcm2835aux.o
 obj-$(CONFIG_SPI_BCM53XX)		+= spi-bcm53xx.o
 obj-$(CONFIG_SPI_BCM63XX)		+= spi-bcm63xx.o
 obj-$(CONFIG_SPI_BCM63XX_HSSPI)		+= spi-bcm63xx-hsspi.o
+obj-$(CONFIG_SPI_BCM_QSPI)		+= spi-bcm-qspi.o
 obj-$(CONFIG_SPI_BFIN5XX)		+= spi-bfin5xx.o
 obj-$(CONFIG_SPI_ADI_V3)                += spi-adi-v3.o
 obj-$(CONFIG_SPI_BFIN_SPORT)		+= spi-bfin-sport.o

drivers/spi/spi-bcm-qspi.c

+/*
+ * Driver for Broadcom BRCMSTB, NSP,  NS2, Cygnus SPI Controllers
+ *
+ * Copyright 2016 Broadcom
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation (the "GPL").
+ *
+ * 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 version 2 (GPLv2) for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 (GPLv2) along with this source code.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mtd/cfi.h>
+#include <linux/mtd/spi-nor.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+#include "spi-bcm-qspi.h"
+
+#define DRIVER_NAME "bcm_qspi"
+
+/* MSPI register offsets */
+#define MSPI_SPCR0_LSB				0x000
+#define MSPI_SPCR0_MSB				0x004
+#define MSPI_SPCR1_LSB				0x008
+#define MSPI_SPCR1_MSB				0x00c
+#define MSPI_NEWQP				0x010
+#define MSPI_ENDQP				0x014
+#define MSPI_SPCR2				0x018
+#define MSPI_MSPI_STATUS			0x020
+#define MSPI_CPTQP				0x024
+#define MSPI_SPCR3				0x028
+#define MSPI_TXRAM				0x040
+#define MSPI_RXRAM				0x0c0
+#define MSPI_CDRAM				0x140
+#define MSPI_WRITE_LOCK			0x180
+
+#define MSPI_MASTER_BIT			BIT(7)
+
+#define MSPI_NUM_CDRAM				16
+#define MSPI_CDRAM_CONT_BIT			BIT(7)
+#define MSPI_CDRAM_BITSE_BIT			BIT(6)
+#define MSPI_CDRAM_PCS				0xf
+
+#define MSPI_SPCR2_SPE				BIT(6)
+#define MSPI_SPCR2_CONT_AFTER_CMD		BIT(7)
+
+#define MSPI_MSPI_STATUS_SPIF			BIT(0)
+
+#define INTR_BASE_BIT_SHIFT			0x02
+#define INTR_COUNT				0x07
+
+#define NUM_CHIPSELECT				4
+#define QSPI_SPBR_MIN				8U
+#define QSPI_SPBR_MAX				255U
+
+#define OPCODE_DIOR				0xBB
+#define OPCODE_QIOR				0xEB
+#define OPCODE_DIOR_4B				0xBC
+#define OPCODE_QIOR_4B				0xEC
+
+#define MAX_CMD_SIZE				6
+
+#define ADDR_4MB_MASK				GENMASK(22, 0)
+
+/* stop at end of transfer, no other reason */
+#define TRANS_STATUS_BREAK_NONE		0
+/* stop at end of spi_message */
+#define TRANS_STATUS_BREAK_EOM			1
+/* stop at end of spi_transfer if delay */
+#define TRANS_STATUS_BREAK_DELAY		2
+/* stop at end of spi_transfer if cs_change */
+#define TRANS_STATUS_BREAK_CS_CHANGE		4
+/* stop if we run out of bytes */
+#define TRANS_STATUS_BREAK_NO_BYTES		8
+
+/* events that make us stop filling TX slots */
+#define TRANS_STATUS_BREAK_TX (TRANS_STATUS_BREAK_EOM |		\
+			       TRANS_STATUS_BREAK_DELAY |		\
+			       TRANS_STATUS_BREAK_CS_CHANGE)
+
+/* events that make us deassert CS */
+#define TRANS_STATUS_BREAK_DESELECT (TRANS_STATUS_BREAK_EOM |		\
+				     TRANS_STATUS_BREAK_CS_CHANGE)
+
+struct bcm_qspi_parms {
+	u32 speed_hz;
+	u8 mode;
+	u8 bits_per_word;
+};
+
+enum base_type {
+	MSPI,
+	CHIP_SELECT,
+	BASEMAX,
+};
+
+struct bcm_qspi_irq {
+	const char *irq_name;
+	const irq_handler_t irq_handler;
+	u32 mask;
+};
+
+struct bcm_qspi_dev_id {
+	const struct bcm_qspi_irq *irqp;
+	void *dev;
+};
+
+struct qspi_trans {
+	struct spi_transfer *trans;
+	int byte;
+};
+
+struct bcm_qspi {
+	struct platform_device *pdev;
+	struct spi_master *master;
+	struct clk *clk;
+	u32 base_clk;
+	u32 max_speed_hz;
+	void __iomem *base[BASEMAX];
+	struct bcm_qspi_parms last_parms;
+	struct qspi_trans  trans_pos;
+	int curr_cs;
+	u32 s3_strap_override_ctrl;
+	bool big_endian;
+	int num_irqs;
+	struct bcm_qspi_dev_id *dev_ids;
+	struct completion mspi_done;
+};
+
+/* Read qspi controller register*/
+static inline u32 bcm_qspi_read(struct bcm_qspi *qspi, enum base_type type,
+				unsigned int offset)
+{
+	return bcm_qspi_readl(qspi->big_endian, qspi->base[type] + offset);
+}
+
+/* Write qspi controller register*/
+static inline void bcm_qspi_write(struct bcm_qspi *qspi, enum base_type type,
+				  unsigned int offset, unsigned int data)
+{
+	bcm_qspi_writel(qspi->big_endian, data, qspi->base[type] + offset);
+}
+
+static void bcm_qspi_chip_select(struct bcm_qspi *qspi, int cs)
+{
+	u32 data = 0;
+
+	if (qspi->curr_cs == cs)
+		return;
+	if (qspi->base[CHIP_SELECT]) {
+		data = bcm_qspi_read(qspi, CHIP_SELECT, 0);
+		data = (data & ~0xff) | (1 << cs);
+		bcm_qspi_write(qspi, CHIP_SELECT, 0, data);
+		usleep_range(10, 20);
+	}
+	qspi->curr_cs = cs;
+}
+
+/* MSPI helpers */
+static void bcm_qspi_hw_set_parms(struct bcm_qspi *qspi,
+				  const struct bcm_qspi_parms *xp)
+{
+	u32 spcr, spbr = 0;
+
+	if (xp->speed_hz)
+		spbr = qspi->base_clk / (2 * xp->speed_hz);
+
+	spcr = clamp_val(spbr, QSPI_SPBR_MIN, QSPI_SPBR_MAX);
+	bcm_qspi_write(qspi, MSPI, MSPI_SPCR0_LSB, spcr);
+
+	spcr = MSPI_MASTER_BIT;
+	/* for 16 bit the data should be zero */
+	if (xp->bits_per_word != 16)
+		spcr |= xp->bits_per_word << 2;
+	spcr |= xp->mode & 3;
+	bcm_qspi_write(qspi, MSPI, MSPI_SPCR0_MSB, spcr);
+
+	qspi->last_parms = *xp;
+}
+
+static void bcm_qspi_update_parms(struct bcm_qspi *qspi,
+				  struct spi_device *spi,
+				  struct spi_transfer *trans)
+{
+	struct bcm_qspi_parms xp;
+
+	xp.speed_hz = trans->speed_hz;
+	xp.bits_per_word = trans->bits_per_word;
+	xp.mode = spi->mode;
+
+	bcm_qspi_hw_set_parms(qspi, &xp);
+}
+
+static int bcm_qspi_setup(struct spi_device *spi)
+{
+	struct bcm_qspi_parms *xp;
+
+	if (spi->bits_per_word > 16)
+		return -EINVAL;
+
+	xp = spi_get_ctldata(spi);
+	if (!xp) {
+		xp = kzalloc(sizeof(*xp), GFP_KERNEL);
+		if (!xp)
+			return -ENOMEM;
+		spi_set_ctldata(spi, xp);
+	}
+	xp->speed_hz = spi->max_speed_hz;
+	xp->mode = spi->mode;
+
+	if (spi->bits_per_word)
+		xp->bits_per_word = spi->bits_per_word;
+	else
+		xp->bits_per_word = 8;
+
+	return 0;
+}
+
+static int update_qspi_trans_byte_count(struct bcm_qspi *qspi,
+					struct qspi_trans *qt, int flags)
+{
+	int ret = TRANS_STATUS_BREAK_NONE;
+
+	/* count the last transferred bytes */
+	if (qt->trans->bits_per_word <= 8)
+		qt->byte++;
+	else
+		qt->byte += 2;
+
+	if (qt->byte >= qt->trans->len) {
+		/* we're at the end of the spi_transfer */
+
+		/* in TX mode, need to pause for a delay or CS change */
+		if (qt->trans->delay_usecs &&
+		    (flags & TRANS_STATUS_BREAK_DELAY))
+			ret |= TRANS_STATUS_BREAK_DELAY;
+		if (qt->trans->cs_change &&
+		    (flags & TRANS_STATUS_BREAK_CS_CHANGE))
+			ret |= TRANS_STATUS_BREAK_CS_CHANGE;
+		if (ret)
+			goto done;
+
+		dev_dbg(&qspi->pdev->dev, "advance msg exit\n");
+		if (spi_transfer_is_last(qspi->master, qt->trans))
+			ret = TRANS_STATUS_BREAK_EOM;
+		else
+			ret = TRANS_STATUS_BREAK_NO_BYTES;
+
+		qt->trans = NULL;
+	}
+
+done:
+	dev_dbg(&qspi->pdev->dev, "trans %p len %d byte %d ret %x\n",
+		qt->trans, qt->trans ? qt->trans->len : 0, qt->byte, ret);
+	return ret;
+}
+
+static inline u8 read_rxram_slot_u8(struct bcm_qspi *qspi, int slot)
+{
+	u32 slot_offset = MSPI_RXRAM + (slot << 3) + 0x4;
+
+	/* mask out reserved bits */
+	return bcm_qspi_read(qspi, MSPI, slot_offset) & 0xff;
+}
+
+static inline u16 read_rxram_slot_u16(struct bcm_qspi *qspi, int slot)
+{
+	u32 reg_offset = MSPI_RXRAM;
+	u32 lsb_offset = reg_offset + (slot << 3) + 0x4;
+	u32 msb_offset = reg_offset + (slot << 3);
+
+	return (bcm_qspi_read(qspi, MSPI, lsb_offset) & 0xff) |
+		((bcm_qspi_read(qspi, MSPI, msb_offset) & 0xff) << 8);
+}
+
+static void read_from_hw(struct bcm_qspi *qspi, int slots)
+{
+	struct qspi_trans tp;
+	int slot;
+
+	if (slots > MSPI_NUM_CDRAM) {
+		/* should never happen */
+		dev_err(&qspi->pdev->dev, "%s: too many slots!\n", __func__);
+		return;
+	}
+
+	tp = qspi->trans_pos;
+
+	for (slot = 0; slot < slots; slot++) {
+		if (tp.trans->bits_per_word <= 8) {
+			u8 *buf = tp.trans->rx_buf;
+
+			if (buf)
+				buf[tp.byte] = read_rxram_slot_u8(qspi, slot);
+			dev_dbg(&qspi->pdev->dev, "RD %02x\n",
+				buf ? buf[tp.byte] : 0xff);
+		} else {
+			u16 *buf = tp.trans->rx_buf;
+
+			if (buf)
+				buf[tp.byte / 2] = read_rxram_slot_u16(qspi,
+								      slot);
+			dev_dbg(&qspi->pdev->dev, "RD %04x\n",
+				buf ? buf[tp.byte] : 0xffff);
+		}
+
+		update_qspi_trans_byte_count(qspi, &tp,
+					     TRANS_STATUS_BREAK_NONE);
+	}
+
+	qspi->trans_pos = tp;
+}
+
+static inline void write_txram_slot_u8(struct bcm_qspi *qspi, int slot,
+				       u8 val)
+{
+	u32 reg_offset = MSPI_TXRAM + (slot << 3);
+
+	/* mask out reserved bits */
+	bcm_qspi_write(qspi, MSPI, reg_offset, val);
+}
+
+static inline void write_txram_slot_u16(struct bcm_qspi *qspi, int slot,
+					u16 val)
+{
+	u32 reg_offset = MSPI_TXRAM;
+	u32 msb_offset = reg_offset + (slot << 3);
+	u32 lsb_offset = reg_offset + (slot << 3) + 0x4;
+
+	bcm_qspi_write(qspi, MSPI, msb_offset, (val >> 8));
+	bcm_qspi_write(qspi, MSPI, lsb_offset, (val & 0xff));
+}
+
+static inline u32 read_cdram_slot(struct bcm_qspi *qspi, int slot)
+{
+	return bcm_qspi_read(qspi, MSPI, MSPI_CDRAM + (slot << 2));
+}
+
+static inline void write_cdram_slot(struct bcm_qspi *qspi, int slot, u32 val)
+{
+	bcm_qspi_write(qspi, MSPI, (MSPI_CDRAM + (slot << 2)), val);
+}
+
+/* Return number of slots written */
+static int write_to_hw(struct bcm_qspi *qspi, struct spi_device *spi)
+{
+	struct qspi_trans tp;
+	int slot = 0, tstatus = 0;
+	u32 mspi_cdram = 0;
+
+	tp = qspi->trans_pos;
+	bcm_qspi_update_parms(qspi, spi, tp.trans);
+
+	/* Run until end of transfer or reached the max data */
+	while (!tstatus && slot < MSPI_NUM_CDRAM) {
+		if (tp.trans->bits_per_word <= 8) {
+			const u8 *buf = tp.trans->tx_buf;
+			u8 val = buf ? buf[tp.byte] : 0xff;
+
+			write_txram_slot_u8(qspi, slot, val);
+			dev_dbg(&qspi->pdev->dev, "WR %02x\n", val);
+		} else {
+			const u16 *buf = tp.trans->tx_buf;
+			u16 val = buf ? buf[tp.byte / 2] : 0xffff;
+
+			write_txram_slot_u16(qspi, slot, val);
+			dev_dbg(&qspi->pdev->dev, "WR %04x\n", val);
+		}
+		mspi_cdram = MSPI_CDRAM_CONT_BIT;
+		mspi_cdram |= (~(1 << spi->chip_select) &
+			       MSPI_CDRAM_PCS);
+		mspi_cdram |= ((tp.trans->bits_per_word <= 8) ? 0 :
+				MSPI_CDRAM_BITSE_BIT);
+
+		write_cdram_slot(qspi, slot, mspi_cdram);
+
+		tstatus = update_qspi_trans_byte_count(qspi, &tp,
+						       TRANS_STATUS_BREAK_TX);
+		slot++;
+	}
+
+	if (!slot) {
+		dev_err(&qspi->pdev->dev, "%s: no data to send?", __func__);
+		goto done;
+	}
+
+	dev_dbg(&qspi->pdev->dev, "submitting %d slots\n", slot);
+	bcm_qspi_write(qspi, MSPI, MSPI_NEWQP, 0);
+	bcm_qspi_write(qspi, MSPI, MSPI_ENDQP, slot - 1);
+
+	if (tstatus & TRANS_STATUS_BREAK_DESELECT) {
+		mspi_cdram = read_cdram_slot(qspi, slot - 1) &
+			~MSPI_CDRAM_CONT_BIT;
+		write_cdram_slot(qspi, slot - 1, mspi_cdram);
+	}
+
+	/* Must flush previous writes before starting MSPI operation */
+	mb();
+	/* Set cont | spe | spifie */
+	bcm_qspi_write(qspi, MSPI, MSPI_SPCR2, 0xe0);
+
+done:
+	return slot;
+}
+
+static int bcm_qspi_transfer_one(struct spi_master *master,
+				 struct spi_device *spi,
+				 struct spi_transfer *trans)
+{
+	struct bcm_qspi *qspi = spi_master_get_devdata(master);
+	int slots;
+	unsigned long timeo = msecs_to_jiffies(100);
+
+	bcm_qspi_chip_select(qspi, spi->chip_select);
+	qspi->trans_pos.trans = trans;
+	qspi->trans_pos.byte = 0;
+
+	while (qspi->trans_pos.byte < trans->len) {
+		reinit_completion(&qspi->mspi_done);
+
+		slots = write_to_hw(qspi, spi);
+		if (!wait_for_completion_timeout(&qspi->mspi_done, timeo)) {
+			dev_err(&qspi->pdev->dev, "timeout waiting for MSPI\n");
+			return -ETIMEDOUT;
+		}
+
+		read_from_hw(qspi, slots);
+	}
+
+	return 0;
+}
+
+static void bcm_qspi_cleanup(struct spi_device *spi)
+{
+	struct bcm_qspi_parms *xp = spi_get_ctldata(spi);
+
+	kfree(xp);
+}
+
+static irqreturn_t bcm_qspi_mspi_l2_isr(int irq, void *dev_id)
+{
+	struct bcm_qspi_dev_id *qspi_dev_id = dev_id;
+	struct bcm_qspi *qspi = qspi_dev_id->dev;
+	u32 status = bcm_qspi_read(qspi, MSPI, MSPI_MSPI_STATUS);
+
+	if (status & MSPI_MSPI_STATUS_SPIF) {
+		/* clear interrupt */
+		status &= ~MSPI_MSPI_STATUS_SPIF;
+		bcm_qspi_write(qspi, MSPI, MSPI_MSPI_STATUS, status);
+		complete(&qspi->mspi_done);
+		return IRQ_HANDLED;
+	} else {
+		return IRQ_NONE;
+	}
+}
+
+static const struct bcm_qspi_irq qspi_irq_tab[] = {
+	{
+		.irq_name = "mspi_done",
+		.irq_handler = bcm_qspi_mspi_l2_isr,
+		.mask = INTR_MSPI_DONE_MASK,
+	},
+	{
+		.irq_name = "mspi_halted",
+		.irq_handler = bcm_qspi_mspi_l2_isr,
+		.mask = INTR_MSPI_HALTED_MASK,
+	},
+};
+
+static void bcm_qspi_hw_init(struct bcm_qspi *qspi)
+{
+	struct bcm_qspi_parms parms;
+
+	bcm_qspi_write(qspi, MSPI, MSPI_SPCR1_LSB, 0);
+	bcm_qspi_write(qspi, MSPI, MSPI_SPCR1_MSB, 0);
+	bcm_qspi_write(qspi, MSPI, MSPI_NEWQP, 0);
+	bcm_qspi_write(qspi, MSPI, MSPI_ENDQP, 0);
+	bcm_qspi_write(qspi, MSPI, MSPI_SPCR2, 0x20);
+
+	parms.mode = SPI_MODE_3;
+	parms.bits_per_word = 8;
+	parms.speed_hz = qspi->max_speed_hz;
+	bcm_qspi_hw_set_parms(qspi, &parms);
+}
+
+static void bcm_qspi_hw_uninit(struct bcm_qspi *qspi)
+{
+	bcm_qspi_write(qspi, MSPI, MSPI_SPCR2, 0);
+}
+
+static const struct of_device_id bcm_qspi_of_match[] = {
+	{ .compatible = "brcm,spi-bcm-qspi" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, bcm_qspi_of_match);
+
+int bcm_qspi_probe(struct platform_device *pdev,
+		   struct bcm_qspi_soc_intc *soc)
+{
+	struct device *dev = &pdev->dev;
+	struct bcm_qspi *qspi;
+	struct spi_master *master;
+	struct resource *res;
+	int irq, ret = 0, num_ints = 0;
+	u32 val;
+	const char *name = NULL;
+	int num_irqs = ARRAY_SIZE(qspi_irq_tab);
+
+	/* We only support device-tree instantiation */
+	if (!dev->of_node)
+		return -ENODEV;
+
+	if (!of_match_node(bcm_qspi_of_match, dev->of_node))
+		return -ENODEV;
+
+	master = spi_alloc_master(dev, sizeof(struct bcm_qspi));
+	if (!master) {
+		dev_err(dev, "error allocating spi_master\n");
+		return -ENOMEM;
+	}
+
+	qspi = spi_master_get_devdata(master);
+	qspi->pdev = pdev;
+	qspi->trans_pos.trans = NULL;
+	qspi->trans_pos.byte = 0;
+	qspi->master = master;
+
+	master->bus_num = -1;
+	master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_RX_DUAL | SPI_RX_QUAD;
+	master->setup = bcm_qspi_setup;
+	master->transfer_one = bcm_qspi_transfer_one;
+	master->cleanup = bcm_qspi_cleanup;
+	master->dev.of_node = dev->of_node;
+	master->num_chipselect = NUM_CHIPSELECT;
+
+	qspi->big_endian = of_device_is_big_endian(dev->of_node);
+
+	if (!of_property_read_u32(dev->of_node, "num-cs", &val))
+		master->num_chipselect = val;
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "hif_mspi");
+	if (!res)
+		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+						   "mspi");
+
+	if (res) {
+		qspi->base[MSPI]  = devm_ioremap_resource(dev, res);
+		if (IS_ERR(qspi->base[MSPI])) {
+			ret = PTR_ERR(qspi->base[MSPI]);
+			goto qspi_probe_err;
+		}
+	} else {
+		goto qspi_probe_err;
+	}
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cs_reg");
+	if (res) {
+		qspi->base[CHIP_SELECT]  = devm_ioremap_resource(dev, res);
+		if (IS_ERR(qspi->base[CHIP_SELECT])) {
+			ret = PTR_ERR(qspi->base[CHIP_SELECT]);
+			goto qspi_probe_err;
+		}
+	}
+
+	qspi->dev_ids = kcalloc(num_irqs, sizeof(struct bcm_qspi_dev_id),
+				GFP_KERNEL);
+	if (IS_ERR(qspi->dev_ids)) {
+		ret = PTR_ERR(qspi->dev_ids);
+		goto qspi_probe_err;
+	}
+
+	for (val = 0; val < num_irqs; val++) {
+		irq = -1;
+		name = qspi_irq_tab[val].irq_name;
+		irq = platform_get_irq_byname(pdev, name);
+
+		if (irq  >= 0) {
+			ret = devm_request_irq(&pdev->dev, irq,
+					       qspi_irq_tab[val].irq_handler, 0,
+					       name,
+					       &qspi->dev_ids[val]);
+			if (ret < 0) {
+				dev_err(&pdev->dev, "IRQ %s not found\n", name);
+				goto qspi_probe_err;
+			}
+
+			qspi->dev_ids[val].dev = qspi;
+			qspi->dev_ids[val].irqp = &qspi_irq_tab[val];
+			num_ints++;
+			dev_dbg(&pdev->dev, "registered IRQ %s %d\n",
+				qspi_irq_tab[val].irq_name,
+				irq);
+		}
+	}
+
+	if (!num_ints) {
+		dev_err(&pdev->dev, "no IRQs registered, cannot init driver\n");
+		goto qspi_probe_err;
+	}
+
+	qspi->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(qspi->clk)) {
+		dev_warn(dev, "unable to get clock\n");
+		goto qspi_probe_err;
+	}
+
+	ret = clk_prepare_enable(qspi->clk);
+	if (ret) {
+		dev_err(dev, "failed to prepare clock\n");
+		goto qspi_probe_err;
+	}
+
+	qspi->base_clk = clk_get_rate(qspi->clk);
+	qspi->max_speed_hz = qspi->base_clk / (QSPI_SPBR_MIN * 2);
+
+	bcm_qspi_hw_init(qspi);
+	init_completion(&qspi->mspi_done);
+	qspi->curr_cs = -1;
+
+	platform_set_drvdata(pdev, qspi);
+	ret = devm_spi_register_master(&pdev->dev, master);
+	if (ret < 0) {
+		dev_err(dev, "can't register master\n");
+		goto qspi_reg_err;
+	}
+
+	return 0;
+
+qspi_reg_err:
+	bcm_qspi_hw_uninit(qspi);
+	clk_disable_unprepare(qspi->clk);
+qspi_probe_err:
+	spi_master_put(master);
+	kfree(qspi->dev_ids);
+	return ret;
+}
+/* probe function to be called by SoC specific platform driver probe */
+EXPORT_SYMBOL_GPL(bcm_qspi_probe);
+
+int bcm_qspi_remove(struct platform_device *pdev)
+{
+	struct bcm_qspi *qspi = platform_get_drvdata(pdev);
+
+	platform_set_drvdata(pdev, NULL);
+	bcm_qspi_hw_uninit(qspi);
+	clk_disable_unprepare(qspi->clk);
+	kfree(qspi->dev_ids);
+	spi_unregister_master(qspi->master);
+
+	return 0;
+}
+/* function to be called by SoC specific platform driver remove() */
+EXPORT_SYMBOL_GPL(bcm_qspi_remove);
+
+#ifdef CONFIG_PM_SLEEP
+static int bcm_qspi_suspend(struct device *dev)
+{
+	struct bcm_qspi *qspi = dev_get_drvdata(dev);
+
+	spi_master_suspend(qspi->master);
+	clk_disable(qspi->clk);
+	bcm_qspi_hw_uninit(qspi);
+
+	return 0;
+};
+
+static int bcm_qspi_resume(struct device *dev)
+{
+	struct bcm_qspi *qspi = dev_get_drvdata(dev);
+	int ret = 0;
+
+	bcm_qspi_hw_init(qspi);
+	bcm_qspi_chip_select(qspi, qspi->curr_cs);
+	ret = clk_enable(qspi->clk);
+	if (!ret)
+		spi_master_resume(qspi->master);
+
+	return ret;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+const struct dev_pm_ops bcm_qspi_pm_ops = {
+	.suspend = bcm_qspi_suspend,
+	.resume  = bcm_qspi_resume,
+};
+/* pm_ops to be called by SoC specific platform driver */
+EXPORT_SYMBOL_GPL(bcm_qspi_pm_ops);
+
+MODULE_AUTHOR("Kamal Dasu");
+MODULE_DESCRIPTION("Broadcom QSPI driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRIVER_NAME);

drivers/spi/spi-bcm-qspi.h

+/*
+ * Copyright 2016 Broadcom
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation (the "GPL").
+ *
+ * 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 version 2 (GPLv2) for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 (GPLv2) along with this source code.
+ */
+
+#ifndef __SPI_BCM_QSPI_H__
+#define __SPI_BCM_QSPI_H__
+
+#include <linux/types.h>
+#include <linux/io.h>
+
+/* MSPI Interrupt masks */
+#define INTR_MSPI_HALTED_MASK			BIT(6)
+#define INTR_MSPI_DONE_MASK			BIT(5)
+
+#define MSPI_INTERRUPTS_ALL		       \
+	(INTR_MSPI_DONE_MASK |		       \
+	 INTR_MSPI_HALTED_MASK)
+
+struct platform_device;
+struct dev_pm_ops;
+
+struct bcm_qspi_soc_intc;
+
+/* Read controller register*/
+static inline u32 bcm_qspi_readl(bool be, void __iomem *addr)
+{
+	if (be)
+		return ioread32be(addr);
+	else
+		return readl_relaxed(addr);
+}
+
+/* Write controller register*/
+static inline void bcm_qspi_writel(bool be,
+				   unsigned int data, void __iomem *addr)
+{
+	if (be)
+		iowrite32be(data, addr);
+	else
+		writel_relaxed(data, addr);
+}
+
+/* The common driver functions to be called by the SoC platform driver */
+int bcm_qspi_probe(struct platform_device *pdev,
+		   struct bcm_qspi_soc_intc *soc_intc);
+int bcm_qspi_remove(struct platform_device *pdev);
+
+/* pm_ops used by the SoC platform driver called on PM suspend/resume */
+extern const struct dev_pm_ops bcm_qspi_pm_ops;
+
+#endif /* __SPI_BCM_QSPI_H__ */