ASR_BASE

Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/drivers/spi/spi-asr.c b/marvell/linux/drivers/spi/spi-asr.c
new file mode 100644
index 0000000..e5f92aa
--- /dev/null
+++ b/marvell/linux/drivers/spi/spi-asr.c
@@ -0,0 +1,1541 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Support for asr spi controller
+ *
+ * Copyright (C) 2019 ASR Micro Limited
+ *
+ * Tim Wang <timwang@asrmicro.com>
+ */
+
+#include <linux/err.h>
+#include <linux/bitops.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/ioport.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+#include <linux/of_device.h>
+#include <linux/delay.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/pm_runtime.h>
+#include <linux/acpi.h>
+
+#include "spi-asr.h"
+
+MODULE_AUTHOR("Tim Wang");
+MODULE_DESCRIPTION("ASR SPI Controller");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:asr-spi");
+
+#define TIMOUT_DFLT		8000
+#define TIMOUT_DFLT_SLAVE	10000
+#define SLAVE_RX_TIMER_MS	1000
+
+static BLOCKING_NOTIFIER_HEAD(removed_notifier_list);
+
+/* #define CONFIG_ASR_SSP_DEBUG	1 */
+
+static bool asr_spi_txfifo_full(const struct spi_driver_data *drv_data)
+{
+	return !(asr_spi_read(drv_data, STATUS) & STATUS_TNF);
+}
+
+static u32 asr_configure_topctrl(const struct spi_driver_data *drv_data, u8 bits)
+{
+	/*
+	 * set Motorola Frame Format
+	 * set DSS
+	 */
+	return TOP_FRF_Motorola | TOP_DSS(bits);
+}
+
+static void set_dvfm_constraint(struct spi_driver_data *drv_data)
+{
+#ifdef CONFIG_PM
+	if (drv_data->qos_idle_value != PM_QOS_CPUIDLE_BLOCK_DEFAULT_VALUE)
+		pm_qos_update_request(&drv_data->qos_idle,
+				drv_data->qos_idle_value);
+#endif
+}
+
+static void unset_dvfm_constraint(struct spi_driver_data *drv_data)
+{
+#ifdef CONFIG_PM
+	if (drv_data->qos_idle_value != PM_QOS_CPUIDLE_BLOCK_DEFAULT_VALUE)
+		pm_qos_update_request(&drv_data->qos_idle,
+					PM_QOS_CPUIDLE_BLOCK_DEFAULT_VALUE);
+#endif
+}
+
+static void init_dvfm_constraint(struct spi_driver_data *drv_data)
+{
+#ifdef CONFIG_PM
+	drv_data->qos_idle.name = "spi-asr";
+	pm_qos_add_request(&drv_data->qos_idle, PM_QOS_CPUIDLE_BLOCK,
+			PM_QOS_CPUIDLE_BLOCK_DEFAULT_VALUE);
+#endif
+}
+
+static void deinit_dvfm_constraint(struct spi_driver_data *drv_data)
+{
+#ifdef CONFIG_PM
+	pm_qos_remove_request(&drv_data->qos_idle);
+#endif
+}
+
+static void cs_assert(struct spi_driver_data *drv_data)
+{
+	struct chip_data *chip = drv_data->cur_chip;
+
+	drv_data->cs_assert = 1;
+
+	if (chip->cs_control) {
+		chip->cs_control(ASR_CS_ASSERT);
+		return;
+	}
+
+	if (drv_data->hold_frame_low || drv_data->cs_comb_ctrl) {
+		asr_spi_write(drv_data, TOP_CTRL, asr_spi_read(drv_data, TOP_CTRL) | TOP_HOLD_FRAME_LOW );
+		return;
+	}
+
+	if (gpio_is_valid(chip->gpio_cs)) {
+		gpio_set_value(chip->gpio_cs, chip->gpio_cs_inverted);
+		return;
+	}
+}
+
+static void cs_deassert(struct spi_driver_data *drv_data)
+{
+	struct chip_data *chip = drv_data->cur_chip;
+
+	drv_data->cs_assert = 0;
+
+	if (chip->cs_control) {
+		chip->cs_control(ASR_CS_DEASSERT);
+		return;
+	}
+
+	if (drv_data->hold_frame_low || drv_data->cs_comb_ctrl) {
+		asr_spi_write(drv_data, TOP_CTRL, asr_spi_read(drv_data, TOP_CTRL) & ~TOP_HOLD_FRAME_LOW );
+		return;
+	}
+
+	if (gpio_is_valid(chip->gpio_cs)) {
+		gpio_set_value(chip->gpio_cs, !chip->gpio_cs_inverted);
+		return;
+	}
+}
+
+/* clear all rx fifo useless data */
+int asr_spi_flush(struct spi_driver_data *drv_data)
+{
+	unsigned long limit = loops_per_jiffy << 1;
+
+	do {
+		while (asr_spi_read(drv_data, STATUS) & STATUS_RNE)
+			asr_spi_read(drv_data, DATAR);
+	} while ((asr_spi_read(drv_data, STATUS) & STATUS_BSY) && --limit);
+	asr_spi_write(drv_data, STATUS, STATUS_ROR);
+
+	return limit;
+}
+
+static int null_writer(struct spi_driver_data *drv_data)
+{
+	u8 n_bytes = drv_data->n_bytes;
+
+	if (asr_spi_txfifo_full(drv_data)
+		|| (drv_data->tx == drv_data->tx_end))
+		return 0;
+
+	asr_spi_write(drv_data, DATAR, 0);
+	drv_data->tx += n_bytes;
+
+	return 1;
+}
+
+static int null_reader(struct spi_driver_data *drv_data)
+{
+	u8 n_bytes = drv_data->n_bytes;
+
+	while ((asr_spi_read(drv_data, STATUS) & STATUS_RNE)
+	       && (drv_data->rx < drv_data->rx_end)) {
+		asr_spi_read(drv_data, DATAR);
+		drv_data->rx += n_bytes;
+	}
+
+	return drv_data->rx == drv_data->rx_end;
+}
+
+static int u8_writer(struct spi_driver_data *drv_data)
+{
+	if (asr_spi_txfifo_full(drv_data)
+		|| (drv_data->tx == drv_data->tx_end))
+		return 0;
+
+	asr_spi_write(drv_data, DATAR, *(u8 *)(drv_data->tx));
+	++drv_data->tx;
+
+	return 1;
+}
+
+static int u8_reader(struct spi_driver_data *drv_data)
+{
+	while ((asr_spi_read(drv_data, STATUS) & STATUS_RNE)
+	       && (drv_data->rx < drv_data->rx_end)) {
+		*(u8 *)(drv_data->rx) = asr_spi_read(drv_data, DATAR);
+		++drv_data->rx;
+	}
+
+	return drv_data->rx == drv_data->rx_end;
+}
+
+static int u16_writer(struct spi_driver_data *drv_data)
+{
+	if (asr_spi_txfifo_full(drv_data)
+		|| (drv_data->tx == drv_data->tx_end))
+		return 0;
+
+	asr_spi_write(drv_data, DATAR, *(u16 *)(drv_data->tx));
+	drv_data->tx += 2;
+
+	return 1;
+}
+
+static int u16_reader(struct spi_driver_data *drv_data)
+{
+	while ((asr_spi_read(drv_data, STATUS) & STATUS_RNE)
+	       && (drv_data->rx < drv_data->rx_end)) {
+		*(u16 *)(drv_data->rx) = asr_spi_read(drv_data, DATAR);
+		drv_data->rx += 2;
+	}
+
+	return drv_data->rx == drv_data->rx_end;
+}
+
+static int u32_writer(struct spi_driver_data *drv_data)
+{
+	if (asr_spi_txfifo_full(drv_data)
+		|| (drv_data->tx == drv_data->tx_end))
+		return 0;
+
+	asr_spi_write(drv_data, DATAR, *(u32 *)(drv_data->tx));
+	drv_data->tx += 4;
+
+	return 1;
+}
+
+static int u32_reader(struct spi_driver_data *drv_data)
+{
+	while ((asr_spi_read(drv_data, STATUS) & STATUS_RNE)
+	       && (drv_data->rx < drv_data->rx_end)) {
+		*(u32 *)(drv_data->rx) = asr_spi_read(drv_data, DATAR);
+		drv_data->rx += 4;
+	}
+
+	return drv_data->rx == drv_data->rx_end;
+}
+
+void *asr_spi_next_transfer(struct spi_driver_data *drv_data)
+{
+	struct spi_message *msg = drv_data->cur_msg;
+	struct spi_transfer *trans = drv_data->cur_transfer;
+
+	/* Move to next transfer */
+	if (trans->transfer_list.next != &msg->transfers) {
+		drv_data->cur_transfer =
+			list_entry(trans->transfer_list.next,
+					struct spi_transfer,
+					transfer_list);
+		return RUNNING_STATE;
+	} else
+		return DONE_STATE;
+}
+
+/* caller already set message->status; dma and pio irqs are blocked */
+static void giveback(struct spi_driver_data *drv_data)
+{
+	struct spi_transfer* last_transfer;
+	struct spi_message *msg;
+
+	msg = drv_data->cur_msg;
+	drv_data->cur_msg = NULL;
+	drv_data->cur_transfer = NULL;
+
+	last_transfer = list_last_entry(&msg->transfers, struct spi_transfer,
+					transfer_list);
+
+	/* Delay if requested before any change in chip select */
+	if (last_transfer->delay_usecs)
+		udelay(last_transfer->delay_usecs);
+
+	/* Drop chip select UNLESS cs_change is true or we are returning
+	 * a message with an error, or next message is for another chip
+	 */
+	if (!last_transfer->cs_change)
+		cs_deassert(drv_data);
+	else if(!drv_data->unqueued_transfer) {
+		struct spi_message *next_msg;
+
+		/* Holding of cs was hinted, but we need to make sure
+		 * the next message is for the same chip.  Don't waste
+		 * time with the following tests unless this was hinted.
+		 *
+		 * We cannot postpone this until pump_messages, because
+		 * after calling msg->complete (below) the driver that
+		 * sent the current message could be unloaded, which
+		 * could invalidate the cs_control() callback...
+		 */
+
+		/* get a pointer to the next message, if any */
+		next_msg = spi_get_next_queued_message(drv_data->master);
+
+		/* see if the next and current messages point
+		 * to the same chip
+		 */
+		if (next_msg && next_msg->spi != msg->spi)
+			next_msg = NULL;
+		if (!next_msg || msg->state == ERROR_STATE)
+			cs_deassert(drv_data);
+	}
+
+	drv_data->cur_chip = NULL;
+	if (drv_data->unqueued_transfer) {
+		if (msg->complete)
+			msg->complete(msg->context);
+		if (msg->spi->master->auto_runtime_pm) {
+			pm_runtime_mark_last_busy(&drv_data->pdev->dev);
+			pm_runtime_put_autosuspend(&drv_data->pdev->dev);
+		}
+	}
+	else {
+		spi_finalize_current_message(drv_data->master);
+	}
+	unset_dvfm_constraint(drv_data);
+
+	if (drv_data->slave_mode)
+		del_timer(&drv_data->slave_rx_timer);
+}
+
+static int asr_rxfifo_wait_not_empty(struct spi_driver_data *drv_data)
+{
+	u32 status = 0;
+	int timeout = 1000000;
+	do {
+		if(--timeout <= 0)
+			return -ETIMEDOUT;
+		status = asr_spi_read(drv_data, STATUS);
+	}while(!(status & STATUS_RNE));
+
+	return 0;
+}
+
+static int asr_txfifo_wait_empty(struct spi_driver_data *drv_data)
+{
+	int timeout = 1000000;
+	u32 status = 0, entries = 0;
+	do {
+		if(--timeout <= 0)
+			return -ETIMEDOUT;
+		status = asr_spi_read(drv_data, STATUS);
+		entries = (status & STATUS_TFL_MASK) >> STATUS_TFL_BASE;
+	}while((entries != 0) || (!(status & STATUS_TNF)));
+
+	return 0;
+}
+
+static int asr_txfifo_wait_not_empty(struct spi_driver_data *drv_data)
+{
+	int timeout = 1000;
+	u32 status = 0, entries = 0;
+	do {
+		status = asr_spi_read(drv_data, STATUS);
+		entries = (status & STATUS_TFL_MASK) >> STATUS_TFL_BASE;
+		if (entries) //not empty and not full
+			break;
+		else if (!(status & STATUS_TNF)) //full
+			break;
+	}while(--timeout);
+
+	if (timeout)
+		return 0;
+
+	return -ETIMEDOUT;
+}
+
+static void reset_fifo_ctrl(struct spi_driver_data *drv_data)
+{
+	struct chip_data *chip = drv_data->cur_chip;
+	u32 fifo_ctrl = 0;
+
+	fifo_ctrl |= chip->threshold;
+	asr_spi_write(drv_data, FIFO_CTRL, fifo_ctrl);
+}
+
+static void reset_int_en(struct spi_driver_data *drv_data)
+{
+	u32 int_en = 0;
+
+	int_en = asr_spi_read(drv_data, INT_EN);
+	int_en &= ~drv_data->int_cr;
+	asr_spi_write(drv_data, INT_EN, int_en);
+}
+
+static int asr_spi_pio_xfer(struct spi_driver_data *drv_data, int polling)
+{
+	int ret = 0;
+	int timeout =0, write_time = 0;
+
+	if (drv_data->len > ( drv_data->n_bytes * PIO_FIFO_ENTRY_NUM) ||
+		drv_data->pio_cs_auto_deasert )
+	{
+		do {
+			if (drv_data->read(drv_data))
+				return 1;
+
+			if (drv_data->pio_cs_auto_deasert) {
+				asr_txfifo_wait_empty(drv_data);
+
+				if(drv_data->pio_interval_us)
+					udelay(drv_data->pio_interval_us);
+			}
+
+			if (drv_data->cs_comb_ctrl && !drv_data->cs_assert)
+			{
+				ret = drv_data->write(drv_data);
+				WARN_ON_ONCE(asr_txfifo_wait_not_empty(drv_data));
+				cs_assert(drv_data);
+				if (ret)
+					continue;
+				else
+					break;
+			}
+		} while (drv_data->write(drv_data));
+	} else {
+		asr_txfifo_wait_empty(drv_data);
+
+		do {
+			write_time ++;
+		} while (drv_data->write(drv_data) && write_time < PIO_FIFO_ENTRY_NUM);
+
+		if (drv_data->cs_comb_ctrl && !drv_data->cs_assert)
+		{
+			WARN_ON_ONCE(asr_txfifo_wait_not_empty(drv_data));
+			cs_assert(drv_data);
+		}
+
+		asr_rxfifo_wait_not_empty(drv_data);
+
+		if (drv_data->read(drv_data))
+			return 1;
+	}
+
+	if (polling) {
+		timeout =  msecs_to_jiffies(drv_data->len);
+
+		while (timeout--) {
+			asr_rxfifo_wait_not_empty(drv_data);
+			if (drv_data->read(drv_data))
+				return 1;
+		}
+	}
+
+	return (drv_data->rx == drv_data->rx_end);
+}
+
+static void int_error_stop(struct spi_driver_data *drv_data, const char* msg)
+{
+	/* Stop and reset SSP */
+	asr_spi_write(drv_data, STATUS, drv_data->clear_sr);
+	reset_fifo_ctrl(drv_data);
+	reset_int_en(drv_data);
+	asr_spi_write(drv_data, TO, 0);
+	asr_spi_flush(drv_data);
+	asr_spi_write(drv_data, TOP_CTRL,
+			 asr_spi_read(drv_data, TOP_CTRL) & ~(TOP_SSE | TOP_HOLD_FRAME_LOW));
+	dev_err(&drv_data->pdev->dev, "%s\n", msg);
+
+	drv_data->cur_msg->state = ERROR_STATE;
+	asr_spi_pump_transfers(drv_data);
+}
+
+static void int_transfer_complete(struct spi_driver_data *drv_data)
+{
+	/* Stop SSP */
+	asr_spi_write(drv_data, STATUS, drv_data->clear_sr);
+	reset_fifo_ctrl(drv_data);
+	reset_int_en(drv_data);
+	asr_spi_write(drv_data, TO, 0);
+
+	/* Update total byte transferred return count actual bytes read */
+	drv_data->cur_msg->actual_length += drv_data->len -
+				(drv_data->rx_end - drv_data->rx);
+
+	/* Transfer delays and chip select release are
+	 * handled in pump_transfers or giveback
+	 */
+
+	/* Move to next transfer */
+	drv_data->cur_msg->state = asr_spi_next_transfer(drv_data);
+
+	/* Handle end of message */
+	if (drv_data->cur_msg->state == DONE_STATE) {
+		drv_data->cur_msg->status = 0;
+		giveback(drv_data);
+	} else {
+		asr_spi_pump_transfers(drv_data);
+	}
+}
+
+static irqreturn_t interrupt_transfer(struct spi_driver_data *drv_data)
+{
+	u32 irq_mask = (asr_spi_read(drv_data, INT_EN) & INT_EN_TIE) ?
+		       drv_data->mask_sr : drv_data->mask_sr & ~STATUS_TFS;
+
+	u32 irq_status = asr_spi_read(drv_data, STATUS) & irq_mask;
+	if (irq_status & STATUS_ROR) {
+		int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
+		return IRQ_HANDLED;
+	}
+
+	if (irq_status & STATUS_TINT) {
+		asr_spi_write(drv_data, STATUS, STATUS_TINT);
+		if (drv_data->read(drv_data)) {
+			int_transfer_complete(drv_data);
+			return IRQ_HANDLED;
+		}
+	}
+
+	if (asr_spi_pio_xfer(drv_data, 0)) {
+		int_transfer_complete(drv_data);
+		return IRQ_HANDLED;
+	}
+
+	if (drv_data->tx == drv_data->tx_end) {
+		u32 int_en;
+
+		int_en = asr_spi_read(drv_data, INT_EN);
+		int_en &= ~INT_EN_TIE;
+
+		asr_spi_write(drv_data, INT_EN, int_en);
+	}
+
+	/* We did something */
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t ssp_int(int irq, void *dev_id)
+{
+	struct spi_driver_data *drv_data = dev_id;
+	u32 int_en;
+	u32 mask = drv_data->mask_sr;
+	u32 int_status;
+
+	/*
+	 * The IRQ might be shared with other peripherals so we must first
+	 * check that are we RPM suspended or not. If we are we assume that
+	 * the IRQ was not for us (we shouldn't be RPM suspended when the
+	 * interrupt is enabled).
+	 */
+	if (pm_runtime_suspended(&drv_data->pdev->dev))
+		return IRQ_NONE;
+
+	/*
+	 * If the device is not yet in RPM suspended state and we get an
+	 * interrupt that is meant for another device, check if status bits
+	 * are all set to one. That means that the device is already
+	 * powered off.
+	 */
+	int_status = asr_spi_read(drv_data, STATUS);
+	if (int_status == ~0)
+		return IRQ_NONE;
+
+	int_en = asr_spi_read(drv_data, INT_EN);
+
+	/* Ignore possible writes if we don't need to write */
+	if (!(int_en & INT_EN_TIE))
+		mask &= ~STATUS_TFS;
+
+	/* Ignore RX timeout interrupt if it is disabled */
+	if (!(int_en & INT_EN_TINTE))
+		mask &= ~STATUS_TINT;
+
+	if (int_status & (STATUS_ROR | STATUS_TUR )) {
+		dev_warn(&drv_data->pdev->dev, "ROR or TUR 0x%x\n", int_status);
+	}
+
+	if (!(int_status & mask))
+		return IRQ_NONE;
+
+	if (!drv_data->cur_msg) {
+
+		asr_spi_write(drv_data, TOP_CTRL,
+				 asr_spi_read(drv_data, TOP_CTRL)
+				 & ~(TOP_SSE | TOP_HOLD_FRAME_LOW));
+		asr_spi_write(drv_data, INT_EN,
+				 asr_spi_read(drv_data, INT_EN)
+				 & ~drv_data->int_cr);
+		asr_spi_write(drv_data, TO, 0);
+		asr_spi_write(drv_data, STATUS, drv_data->clear_sr);
+
+		dev_err(&drv_data->pdev->dev,
+			"bad message state in interrupt handler\n");
+
+		/* Never fail */
+		return IRQ_HANDLED;
+	}
+
+	return drv_data->transfer_handler(drv_data);
+}
+
+static void slave_rx_timer_expired(struct timer_list *t) {
+	struct spi_driver_data *drv_data = from_timer(drv_data, t, slave_rx_timer);
+#ifdef CONFIG_ASR_SSP_DEBUG
+	pr_err("%s\n", __func__);
+	pr_err("spi top = 0x%x\n", asr_spi_read(drv_data, TOP_CTRL));
+	pr_err("fifo = 0x%x\n", asr_spi_read(drv_data, FIFO_CTRL));
+	pr_err("int_en = 0x%x\n", asr_spi_read(drv_data, INT_EN));
+	pr_err("to = 0x%x\n", asr_spi_read(drv_data, TO));
+#endif
+
+	if(drv_data->dma_mapped)
+		asr_spi_slave_sw_timeout_callback(drv_data);
+}
+
+static int asr_spi_xfer_prepare(struct spi_driver_data *drv_data,
+	u8 buswidth, int pio, int polling)
+{
+	struct chip_data *chip = NULL;
+	u8 bits = 0;
+	u32 top_ctrl;
+	u32 fifo_ctrl;
+	u32 int_en = 0;
+	int mode; /* 0: dma, 1: pio */
+	u32 dma_thresh = drv_data->cur_chip->dma_threshold;
+	u32 dma_burst = drv_data->cur_chip->dma_burst_size;
+
+	bits = buswidth;
+	chip = drv_data->cur_chip;
+	mode = pio;
+
+	drv_data->n_bytes = chip->n_bytes;
+	drv_data->write = drv_data->tx ? chip->write : null_writer;
+	drv_data->read = drv_data->rx ? chip->read : null_reader;
+
+	if (bits <= 8) {
+		drv_data->n_bytes = 1;
+		drv_data->read = drv_data->read != null_reader ?
+					u8_reader : null_reader;
+		drv_data->write = drv_data->write != null_writer ?
+					u8_writer : null_writer;
+	} else if (bits <= 16) {
+		drv_data->n_bytes = 2;
+		drv_data->read = drv_data->read != null_reader ?
+					u16_reader : null_reader;
+		drv_data->write = drv_data->write != null_writer ?
+					u16_writer : null_writer;
+	} else if (bits <= 32) {
+		drv_data->n_bytes = 4;
+		drv_data->read = drv_data->read != null_reader ?
+					u32_reader : null_reader;
+		drv_data->write = drv_data->write != null_writer ?
+					u32_writer : null_writer;
+	}
+
+	top_ctrl = asr_configure_topctrl(drv_data, bits);
+	dev_dbg(&drv_data->master->dev, "%u Hz, %s\n",
+			drv_data->master->max_speed_hz,
+			chip->enable_dma ? "DMA" : "PIO");
+	top_ctrl |= chip->top_ctrl;
+	fifo_ctrl = chip->fifo_ctrl;
+
+	if (drv_data->ssp_enhancement) {
+		/*
+		 * If transfer length is times of 4, then use
+		 * 32 bit fifo width with endian swap support
+		 */
+		if (drv_data->len % 4 == 0 && bits <= 16) {
+			if (bits <= 8)
+				fifo_ctrl |=  FIFO_WR_ENDIAN_8BITS |
+					FIFO_RD_ENDIAN_8BITS;
+			else if (bits <= 16)
+				fifo_ctrl |= FIFO_WR_ENDIAN_16BITS |
+					FIFO_RD_ENDIAN_16BITS;
+			bits = 32;
+			drv_data->n_bytes = 4;
+			if(drv_data->rx)
+				drv_data->read = u32_reader;
+			if(drv_data->tx)
+				drv_data->write = u32_writer;
+
+			top_ctrl &= ~TOP_DSS_MASK;
+			top_ctrl |= TOP_DSS(32);
+		}
+	}
+
+	drv_data->dma_mapped = 0;
+	if (!pio && asr_spi_dma_is_possible(drv_data->len)) {
+		if (chip->enable_dma) {
+			if (asr_spi_set_dma_burst_and_threshold(chip,
+					NULL,
+					bits, &dma_burst,
+					&dma_thresh))
+			dev_warn_ratelimited(&drv_data->master->dev,
+					"DMA burst size reduced to match bits_per_word\n");
+		}
+		drv_data->dma_mapped = asr_spi_map_dma_buffers(drv_data);
+	}
+	if (drv_data->dma_mapped) {
+		/* Ensure we have the correct interrupt handler */
+		drv_data->transfer_handler = asr_spi_dma_transfer;
+
+		asr_spi_dma_prepare(drv_data, dma_burst);
+
+		/* Clear status and start DMA engine */
+		fifo_ctrl |= chip->fifo_ctrl | dma_thresh | drv_data->dma_fifo_ctrl;
+		top_ctrl |= chip->top_ctrl | drv_data->dma_top_ctrl;
+		asr_spi_write(drv_data, STATUS, drv_data->clear_sr);
+		asr_spi_dma_start(drv_data);
+		int_en = asr_spi_read(drv_data, INT_EN) | drv_data->dma_cr;
+	} else {
+		mode = 1;
+		fifo_ctrl = fifo_ctrl | chip->fifo_ctrl | chip->threshold;
+		if (polling || drv_data->xfer_way == XFER_SPIMEM) {
+			int_en = asr_spi_read(drv_data, INT_EN) & ~drv_data->int_cr;
+		} else {
+			/* Ensure we have the correct interrupt handler	*/
+			drv_data->transfer_handler = interrupt_transfer;
+			int_en = asr_spi_read(drv_data, INT_EN) | drv_data->int_cr;
+		}
+		asr_spi_write(drv_data, STATUS, drv_data->clear_sr);
+	}
+
+	asr_spi_write(drv_data, TO, chip->timeout);
+
+	set_dvfm_constraint(drv_data);	/*disable system to idle while DMA */
+	if (drv_data->slave_mode)
+		top_ctrl |= TOP_SSE | TOP_SCLKDIR | TOP_SFRMDIR;
+	else
+		top_ctrl |= drv_data->hold_frame_low;
+	/*
+	 * This part changed the logic
+	 * 1. clear SSE
+	 * 2. write TOP_CTRL and other register
+	 * 3. set SSE in the end of this function
+	 */
+	top_ctrl &= ~TOP_SSE;
+	if (drv_data->cs_comb_ctrl)
+		top_ctrl &= ~TOP_HOLD_FRAME_LOW;
+	asr_spi_write(drv_data, TOP_CTRL, top_ctrl);
+	asr_spi_write(drv_data, FIFO_CTRL, fifo_ctrl);
+	asr_spi_write(drv_data, INT_EN, int_en);
+	if (drv_data->one_cycle_delay)
+		asr_spi_write(drv_data, MISC_CTRL, 1);
+
+#ifdef CONFIG_ASR_SSP_DEBUG
+	dev_err(&drv_data->master->dev, "spi top = 0x%x\n", top_ctrl);
+	dev_err(&drv_data->master->dev, "fifo = 0x%x\n", asr_spi_read(drv_data, FIFO_CTRL));
+	dev_err(&drv_data->master->dev, "int_en = 0x%x\n", asr_spi_read(drv_data, INT_EN));
+	dev_err(&drv_data->master->dev, "to = 0x%x\n", asr_spi_read(drv_data, TO));
+#endif
+	return mode;
+}
+
+static void asr_spi_xfer_start(struct spi_driver_data *drv_data)
+{
+	u32 top_ctrl;
+
+	if (!drv_data->cs_comb_ctrl)
+		cs_assert(drv_data);
+
+	top_ctrl = asr_spi_read(drv_data, TOP_CTRL);
+	top_ctrl |= TOP_SSE;
+	asr_spi_write(drv_data, TOP_CTRL, top_ctrl);
+
+	if (drv_data->cs_comb_ctrl && drv_data->dma_mapped)  {
+		WARN_ON_ONCE(asr_txfifo_wait_not_empty(drv_data));
+		cs_assert(drv_data);
+	}
+}
+
+static void asr_spi_xfer_pause(struct spi_driver_data *drv_data)
+{
+	u32 top_ctrl;
+
+	top_ctrl = asr_spi_read(drv_data, TOP_CTRL);
+	top_ctrl &= ~TOP_SSE;
+	asr_spi_write(drv_data, TOP_CTRL, top_ctrl);
+}
+
+static void asr_spi_xfer_stop(struct spi_driver_data *drv_data)
+{
+	u32 top_ctrl;
+
+	top_ctrl = asr_spi_read(drv_data, TOP_CTRL);
+	top_ctrl &= ~TOP_SSE;
+	asr_spi_write(drv_data, TOP_CTRL, top_ctrl);
+	cs_deassert(drv_data);
+}
+
+static void pump_transfers(unsigned long data)
+{
+	struct spi_driver_data *drv_data = (struct spi_driver_data *)data;
+	struct spi_message *message = NULL;
+	struct spi_transfer *transfer = NULL;
+	struct spi_transfer *previous = NULL;
+	struct chip_data *chip = NULL;
+	u8 bits = 0;
+
+	if (drv_data->slave_mode && drv_data->slave_rxtimer_to_ms)
+		mod_timer(&drv_data->slave_rx_timer,
+			jiffies + msecs_to_jiffies(drv_data->slave_rxtimer_to_ms));
+
+	/* Get current state information */
+	message = drv_data->cur_msg;
+	transfer = drv_data->cur_transfer;
+	chip = drv_data->cur_chip;
+
+	/* Handle for abort */
+	if (message->state == ERROR_STATE) {
+		message->status = -EIO;
+		giveback(drv_data);
+		return;
+	}
+
+	/* Handle end of message */
+	if (message->state == DONE_STATE) {
+		message->status = 0;
+		giveback(drv_data);
+		return;
+	}
+
+	/* Delay if requested at end of transfer before CS change */
+	if (message->state == RUNNING_STATE) {
+		previous = list_entry(transfer->transfer_list.prev,
+					struct spi_transfer,
+					transfer_list);
+		if (previous->delay_usecs)
+			udelay(previous->delay_usecs);
+
+		/* Drop chip select only if cs_change is requested */
+		if (previous->cs_change)
+			cs_deassert(drv_data);
+	}
+
+	/* Check if we can DMA this transfer */
+	if (!asr_spi_dma_is_possible(transfer->len) && chip->enable_dma) {
+		/* reject already-mapped transfers; PIO won't always work */
+		if (message->is_dma_mapped
+				|| transfer->rx_dma || transfer->tx_dma) {
+			dev_err(&drv_data->pdev->dev,
+				"pump_transfers: mapped transfer length of "
+				"%u is greater than %d\n",
+				transfer->len, MAX_DMA_LEN);
+			message->status = -EINVAL;
+			giveback(drv_data);
+			return;
+		}
+
+		/* warn ... we force this to PIO mode */
+		dev_warn_ratelimited(&message->spi->dev,
+				     "pump_transfers: DMA disabled for transfer length %ld "
+				     "greater than %d\n",
+				     (long)drv_data->len, MAX_DMA_LEN);
+	}
+
+	/* Setup the transfer state based on the type of transfer */
+	if (asr_spi_flush(drv_data) == 0) {
+		dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
+		message->status = -EIO;
+		giveback(drv_data);
+		return;
+	}
+
+	drv_data->xfer_way = XFER_PUMP;
+	drv_data->tx = (void *)transfer->tx_buf;
+	drv_data->tx_end = drv_data->tx + transfer->len;
+	drv_data->rx = transfer->rx_buf;
+	drv_data->rx_end = drv_data->rx + transfer->len;
+	drv_data->rx_dma = transfer->rx_dma;
+	drv_data->tx_dma = transfer->tx_dma;
+	drv_data->len = transfer->len;
+
+	/* Change speed and bit per word on a per transfer */
+	bits = transfer->bits_per_word;
+	message->state = RUNNING_STATE;
+
+	asr_spi_xfer_prepare(drv_data, bits, 0, 0);
+
+	asr_spi_xfer_start(drv_data);
+}
+
+void asr_spi_pump_transfers(struct spi_driver_data *drv_data)
+{
+	if (drv_data->no_tasklet)
+		return pump_transfers((unsigned long)drv_data);
+	else
+		tasklet_schedule(&drv_data->pump_transfers);
+}
+
+static int asr_spi_transfer_one_message(struct spi_master *master,
+					   struct spi_message *msg)
+{
+	struct spi_driver_data *drv_data = spi_master_get_devdata(master);
+
+	drv_data->cur_msg = msg;
+	/* Initial message state*/
+	drv_data->cur_msg->state = START_STATE;
+	drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
+						struct spi_transfer,
+						transfer_list);
+
+	/*
+	 * prepare to setup the SSP, in pump_transfers, using the per
+	 * chip configuration
+	 */
+	drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
+
+	if (master->max_speed_hz != drv_data->cur_transfer->speed_hz) {
+		master->max_speed_hz = drv_data->cur_transfer->speed_hz;
+		clk_set_rate(drv_data->clk, master->max_speed_hz);
+	}
+
+	/* Mark as busy and launch transfers */
+	asr_spi_pump_transfers(drv_data);
+	return 0;
+}
+
+static int asr_spi_unqueued_transfer(struct spi_device *spi, struct spi_message *msg)
+{
+	int	status;
+	struct spi_master *master = spi->master;
+	struct spi_driver_data *drv_data = spi_master_get_devdata(master);
+
+	if (master->auto_runtime_pm) {
+		status = pm_runtime_get_sync(spi->master->dev.parent);
+		if (status < 0) {
+			pm_runtime_put_noidle(spi->master->dev.parent);
+			dev_err(&spi->master->dev, "Failed to power device: %d\n",
+					status);
+			return status;
+		}
+	}
+	drv_data->xfer_way = XFER_UNQUEUE;
+	return asr_spi_transfer_one_message(master, msg);
+}
+
+static int asr_spi_unprepare_transfer(struct spi_master *master)
+{
+	struct spi_driver_data *drv_data = spi_master_get_devdata(master);
+
+	/* Disable the SSP now */
+	asr_spi_write(drv_data, TOP_CTRL,
+			 asr_spi_read(drv_data, TOP_CTRL) & ~(TOP_SSE | TOP_HOLD_FRAME_LOW));
+
+	return 0;
+}
+
+static int setup_cs(struct spi_device *spi, struct chip_data *chip)
+{
+	int err = 0;
+
+	if (chip == NULL)
+		return 0;
+
+	if (gpio_is_valid(chip->gpio_cs))
+		gpio_free(chip->gpio_cs);
+
+	if (gpio_is_valid(spi->cs_gpio)) {
+		err = gpio_request(spi->cs_gpio, "SPI_CS");
+		if (err) {
+			dev_err(&spi->dev, "failed to request chip select GPIO%d\n",
+				spi->cs_gpio);
+			return err;
+		}
+
+		chip->gpio_cs = spi->cs_gpio;
+		chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
+
+		err = gpio_direction_output(chip->gpio_cs,
+					!chip->gpio_cs_inverted);
+	}
+
+	return err;
+}
+
+static int setup(struct spi_device *spi)
+{
+	struct chip_data *chip;
+	struct spi_driver_data *drv_data = spi_master_get_devdata(spi->master);
+	uint tx_thres, tx_hi_thres, rx_thres;
+
+	tx_thres = TX_THRESH_DFLT;
+	tx_hi_thres = 0;
+	rx_thres = RX_THRESH_DFLT;
+
+	/* Only alloc on first setup */
+	chip = spi_get_ctldata(spi);
+	if (!chip) {
+		chip = devm_kzalloc(&spi->master->dev, sizeof(struct chip_data),
+				GFP_KERNEL);
+		if (!chip)
+			return -ENOMEM;
+
+		chip->gpio_cs = -1;
+		chip->enable_dma = 0;
+		chip->timeout =
+			drv_data->slave_mode ? drv_data->slave_rxfifo_timeout : drv_data->master_rxfifo_timeout;
+	}
+
+	chip->top_ctrl = 0;
+	chip->fifo_ctrl = 0;
+
+	chip->enable_dma = drv_data->master_info->enable_dma;
+
+	if (chip->enable_dma) {
+		/* set up legal burst and threshold for dma */
+		if (asr_spi_set_dma_burst_and_threshold(chip, spi,
+						spi->bits_per_word,
+						&chip->dma_burst_size,
+						&chip->dma_threshold)) {
+			dev_warn(&spi->dev,
+					"in setup: DMA burst size reduced to match bits_per_word\n");
+		}
+	}
+	chip->threshold = (FIFO_RxTresh(rx_thres) & FIFO_RFT) |
+		(FIFO_TxTresh(tx_thres) & FIFO_TFT);
+
+	chip->top_ctrl &= ~(TOP_SPO | TOP_SPH);
+	chip->top_ctrl |= (((spi->mode & SPI_CPHA) != 0) ? TOP_SPH : 0)
+			| (((spi->mode & SPI_CPOL) != 0) ? TOP_SPO : 0);
+
+	if (spi->mode & SPI_LOOP)
+		chip->top_ctrl |= TOP_LBM;
+
+	/* Enable rx fifo auto full control */
+	if (drv_data->ssp_enhancement && !drv_data->slave_mode )
+		chip->fifo_ctrl |= FIFO_RXFIFO_AUTO_FULL_CTRL;
+
+	if (spi->bits_per_word <= 8) {
+		chip->n_bytes = 1;
+		chip->read = u8_reader;
+		chip->write = u8_writer;
+	} else if (spi->bits_per_word <= 16) {
+		chip->n_bytes = 2;
+		chip->read = u16_reader;
+		chip->write = u16_writer;
+	} else if (spi->bits_per_word <= 32) {
+		chip->n_bytes = 4;
+		chip->read = u32_reader;
+		chip->write = u32_writer;
+	}
+
+	if (spi->master->max_speed_hz != spi->max_speed_hz) {
+		spi->master->max_speed_hz = spi->max_speed_hz;
+		clk_set_rate(drv_data->clk, spi->master->max_speed_hz);
+	}
+
+	spi_set_ctldata(spi, chip);
+
+	return setup_cs(spi, chip);
+}
+
+static void cleanup(struct spi_device *spi)
+{
+	struct chip_data *chip = spi_get_ctldata(spi);
+
+	if (!chip)
+		return;
+
+	if (gpio_is_valid(chip->gpio_cs))
+		gpio_free(chip->gpio_cs);
+
+	devm_kfree(&spi->dev, chip);
+}
+
+static bool asr_spi_mem_supports_op(struct spi_mem *mem,
+				     const struct spi_mem_op *op)
+{
+	if (op->data.buswidth > 1 || op->addr.buswidth > 1 ||
+	    op->dummy.buswidth > 1 || op->cmd.buswidth > 1)
+		return false;
+
+	if (op->data.nbytes && op->dummy.nbytes &&
+	    op->data.buswidth != op->dummy.buswidth)
+		return false;
+
+	if (op->addr.nbytes > 4)
+		return false;
+
+	if (op->cmd.dtr || op->addr.dtr || op->data.dtr)
+		return false;
+
+	return true;
+}
+
+static int asr_spi_mem_exec_op(struct spi_mem *mem,
+				const struct spi_mem_op *op)
+{
+	struct spi_driver_data *drv_data = NULL;
+	u8 *txbuff = NULL;
+	int i, len, ret = 0, pio = 0;
+
+	drv_data = spi_master_get_devdata(mem->spi->master);
+	drv_data->cur_chip = spi_get_ctldata(mem->spi);
+
+	if (asr_spi_flush(drv_data) == 0) {
+		return -EIO;
+	}
+
+	len = 1 + op->addr.nbytes + op->dummy.nbytes;
+	txbuff = kzalloc(len, GFP_KERNEL | GFP_DMA);
+	if (!txbuff)
+		return -ENOMEM;
+
+	drv_data->xfer_way = XFER_SPIMEM;
+
+	txbuff[0] = op->cmd.opcode;
+
+	for (i = 0; i < op->addr.nbytes; i++)
+		txbuff[i+1] = op->addr.val >> (8 * (op->addr.nbytes - i - 1));
+	memset(&txbuff[1 + op->addr.nbytes], 0xa5, op->dummy.nbytes);
+
+	drv_data->len = len;
+	drv_data->tx = txbuff;
+	drv_data->tx_end = drv_data->tx + len;
+	drv_data->rx = NULL;
+	drv_data->rx_end = drv_data->rx + len;
+	/* use pio+polling for cmd/addr/dummy */
+	asr_spi_xfer_prepare(drv_data, 8, 1, 1);
+	asr_spi_xfer_start(drv_data);
+	ret = asr_spi_pio_xfer(drv_data, 1);
+	if (!ret)
+		goto xfer_timeout;
+
+	if (op->data.nbytes) {
+		asr_spi_xfer_pause(drv_data);
+		len = op->data.nbytes;
+		drv_data->len = len;
+		drv_data->tx = (void *)op->data.buf.out;
+		drv_data->tx_end = drv_data->tx + len;
+		drv_data->rx = op->data.buf.in;
+		drv_data->rx_end = drv_data->rx + len;
+		pio = asr_spi_xfer_prepare(drv_data, 8, 0, 0);
+		asr_spi_xfer_start(drv_data);
+		if (pio) { /* pio mode used */
+			ret = asr_spi_pio_xfer(drv_data, 1);
+			if (!ret)
+				goto xfer_timeout;
+		} else {
+			ret = wait_for_completion_timeout(&drv_data->dma_completion,
+							msecs_to_jiffies(len));
+			if (ret <= 0)
+				goto xfer_timeout;
+		}
+	}
+
+	asr_spi_xfer_stop(drv_data);
+	return 0;
+
+xfer_timeout:
+	asr_spi_xfer_stop(drv_data);
+	return -ETIMEDOUT;
+}
+
+static const struct spi_controller_mem_ops asr_spi_mem_ops = {
+	.supports_op = asr_spi_mem_supports_op,
+	.exec_op = asr_spi_mem_exec_op,
+};
+
+static const struct of_device_id asr_spi_dt_ids[] = {
+	{ .compatible = "asr,asr-spi", .data = (void *) ASR_SSP },
+	{}
+};
+MODULE_DEVICE_TABLE(of, asr_spi_dt_ids);
+
+static int asr_spi_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct asr_spi_master *platform_info;
+	struct spi_master *master = NULL;
+	struct spi_driver_data *drv_data = NULL;
+	struct device_node *np = dev->of_node;
+	const struct of_device_id *id =
+		of_match_device(of_match_ptr(asr_spi_dt_ids), dev);
+	struct resource *iores;
+	u32 bus_num;
+	const __be32 *prop;
+	unsigned int proplen;
+	int status;
+	u32 tmp;
+
+	platform_info = dev_get_platdata(dev);
+	if (!platform_info) {
+		platform_info = devm_kzalloc(dev, sizeof(*platform_info),
+				GFP_KERNEL);
+		if (!platform_info)
+			return -ENOMEM;
+
+		if (!of_property_read_u32(np, "asr,spi-cs-num", &tmp))
+			platform_info->num_chipselect = tmp;
+		else
+			platform_info->num_chipselect = 1;
+
+		/* TODO: NO DMA on FPGA yet */
+		if (of_get_property(np, "asr,ssp-disable-dma", NULL))
+			platform_info->enable_dma = 0;
+		else
+			platform_info->enable_dma = 1;
+	}
+
+	master = spi_alloc_master(dev, sizeof(struct spi_driver_data));
+	if (!master) {
+		dev_err(&pdev->dev, "cannot alloc spi_master\n");
+		return -ENOMEM;
+	}
+	drv_data = spi_master_get_devdata(master);
+
+	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (iores == NULL) {
+		dev_err(dev, "no memory resource defined\n");
+		status = -ENODEV;
+		goto out_error_master_alloc;
+	}
+
+	drv_data->ioaddr = devm_ioremap_resource(dev, iores);
+	if (drv_data->ioaddr == NULL) {
+		dev_err(dev, "failed to ioremap() registers\n");
+		status = -ENODEV;
+		goto out_error_master_alloc;
+	}
+
+	drv_data->irq = platform_get_irq(pdev, 0);
+	if (drv_data->irq < 0) {
+		status = -ENODEV;
+		goto out_error_master_alloc;
+	}
+
+	/* Receive FIFO auto full ctrl enable */
+	if (of_get_property(np, "asr,ssp-enhancement", NULL))
+		drv_data->ssp_enhancement = 1;
+
+	if (of_get_property(np, "asr,spi-1-cycle-delay", NULL))
+		drv_data->one_cycle_delay = 1;
+
+	if (of_get_property(np, "asr,ssp-slave-mode", NULL)) {
+		drv_data->slave_mode = 1;
+		dev_warn(&pdev->dev, "slave mode\n");
+		timer_setup(&drv_data->slave_rx_timer,
+				slave_rx_timer_expired, 0);
+
+		if (!of_property_read_u32(np, "asr,slave-rxtimer-to-ms", &tmp))
+			drv_data->slave_rxtimer_to_ms = tmp;
+		else
+			drv_data->slave_rxtimer_to_ms = SLAVE_RX_TIMER_MS;
+	}
+
+	if (!of_property_read_u32(np, "asr,spi-master-rxto", &tmp))
+		drv_data->master_rxfifo_timeout = tmp;
+	else
+		drv_data->master_rxfifo_timeout = TIMOUT_DFLT;
+
+	if (!of_property_read_u32(np, "asr,spi-slave-rxto", &tmp))
+		drv_data->slave_rxfifo_timeout = tmp;
+	else
+		drv_data->slave_rxfifo_timeout = TIMOUT_DFLT_SLAVE;
+
+	if (of_get_property(np, "asr,ssp-hold-frame-low", NULL))
+		drv_data->hold_frame_low = TOP_HOLD_FRAME_LOW;
+
+	if (of_get_property(np, "asr,spi-cs-comb-ctrl", NULL))
+		drv_data->cs_comb_ctrl = 1;
+	
+	prop = of_get_property(dev->of_node, "asr,ssp-lpm-qos", &proplen);
+	if (!prop) {
+		dev_err(&pdev->dev, "lpm-qos for spi is not defined!\n");
+		status = -EINVAL;
+		goto out_error_master_alloc;
+	} else
+		drv_data->qos_idle_value = be32_to_cpup(prop);
+
+	init_dvfm_constraint(drv_data);
+
+	master->dev.of_node = dev->of_node;
+	drv_data->ssp_type = (uintptr_t) id->data;
+	if (!of_property_read_u32(np, "asr,ssp-id", &bus_num))
+		master->bus_num = bus_num;
+	drv_data->ssdr_physical = iores->start + DATAR;
+
+	if (!of_property_read_u32(np, "asr,spi-pio-interval", &tmp)) {
+		drv_data->pio_cs_auto_deasert = 1;
+		drv_data->pio_interval_us = tmp;
+	}
+	else {
+		drv_data->pio_cs_auto_deasert = 0;
+		drv_data->pio_interval_us = 0;
+	}
+
+	if (of_get_property(np, "asr,spi-unqueued-transfer", NULL))
+		drv_data->unqueued_transfer = 1;
+	else
+		drv_data->unqueued_transfer = 0;
+
+	if (of_get_property(np, "asr,spi-no-tasklet", NULL))
+		drv_data->no_tasklet = 1;
+	else
+		drv_data->no_tasklet = 0;
+
+	drv_data->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR_OR_NULL(drv_data->clk)) {
+		dev_err(&pdev->dev, "cannot get clk\n");
+		status = -ENODEV;
+		goto out_error_clk_check;
+	}
+
+	drv_data->master = master;
+	drv_data->master_info = platform_info;
+	drv_data->pdev = pdev;
+
+	master->dev.parent = &pdev->dev;
+	/* the spi->mode bits understood by this driver: */
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
+
+	master->dma_alignment = DMA_ALIGNMENT;
+	master->cleanup = cleanup;
+	master->setup = setup;
+	if (drv_data->unqueued_transfer) {
+		master->transfer = asr_spi_unqueued_transfer;
+		drv_data->no_tasklet = 1;
+	}else{
+		master->transfer_one_message = asr_spi_transfer_one_message;
+	}
+	master->auto_runtime_pm = true;
+	master->unprepare_transfer_hardware = asr_spi_unprepare_transfer;
+
+	if (of_get_property(np, "asr,ssp-spi-mem", NULL)) {
+		init_completion(&drv_data->dma_completion);
+		master->mem_ops = &asr_spi_mem_ops;
+	}
+
+	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
+	drv_data->int_cr = INT_EN_TIE | INT_EN_RIE | INT_EN_TINTE; /* INT_EN */
+	drv_data->dma_cr = INT_EN_RIM | INT_EN_TIM;
+	drv_data->clear_sr = STATUS_ROR | STATUS_TINT;
+	drv_data->mask_sr = STATUS_TINT | STATUS_RFS | STATUS_TFS | STATUS_ROR;
+	drv_data->dma_top_ctrl = DEFAULT_DMA_TOP_CTRL;
+	drv_data->dma_fifo_ctrl = DEFAULT_DMA_FIFO_CTRL;
+
+	status = of_property_read_u32(np, "asr,ssp-clock-rate", &master->max_speed_hz);
+	if (status < 0) {
+		dev_err(&pdev->dev, "cannot get clock-rate from DT file\n");
+		goto out_error_clk_check;
+	}
+
+	status = devm_request_irq(&pdev->dev, drv_data->irq, ssp_int, IRQF_SHARED, dev_name(dev),
+			drv_data);
+	if (status < 0) {
+		dev_err(&pdev->dev, "cannot get IRQ %d\n", drv_data->irq);
+		goto out_error_clk_check;
+	}
+
+	/* Setup DMA if requested */
+	if (platform_info->enable_dma) {
+		status = asr_spi_dma_setup(drv_data);
+		if (status) {
+			dev_dbg(dev, "no DMA channels available, using PIO\n");
+			platform_info->enable_dma = false;
+		}
+	}
+
+	clk_set_rate(drv_data->clk, master->max_speed_hz);
+	master->max_speed_hz = clk_get_rate(drv_data->clk);
+	clk_prepare_enable(drv_data->clk);
+
+	/* Load default SSP configuration */
+	asr_spi_write(drv_data, TOP_CTRL, 0);
+	asr_spi_write(drv_data, FIFO_CTRL, 0);
+	tmp = FIFO_RxTresh(RX_THRESH_DFLT) |
+	      FIFO_TxTresh(TX_THRESH_DFLT);
+	asr_spi_write(drv_data, FIFO_CTRL, tmp);
+	tmp = TOP_FRF_Motorola | TOP_DSS(8);
+	asr_spi_write(drv_data, TOP_CTRL, tmp);
+	asr_spi_write(drv_data, TO, 0);
+
+	asr_spi_write(drv_data, PSP_CTRL, 0);
+
+	master->num_chipselect = platform_info->num_chipselect;
+
+	if (!drv_data->no_tasklet)
+		tasklet_init(&drv_data->pump_transfers, pump_transfers,
+					(unsigned long)drv_data);
+
+	if (master->auto_runtime_pm) {
+		pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
+		pm_runtime_use_autosuspend(&pdev->dev);
+		pm_runtime_set_active(&pdev->dev);
+		pm_runtime_enable(&pdev->dev);
+	}
+
+	/* Register with the SPI framework */
+	platform_set_drvdata(pdev, drv_data);
+	status = devm_spi_register_master(&pdev->dev, master);
+	if (status != 0) {
+		dev_err(&pdev->dev, "problem registering spi master\n");
+		goto out_error_clock_enabled;
+	}
+
+	return status;
+
+out_error_clock_enabled:
+	clk_disable_unprepare(drv_data->clk);
+	asr_spi_dma_release(drv_data);
+	free_irq(drv_data->irq, drv_data);
+out_error_clk_check:
+	deinit_dvfm_constraint(drv_data);
+out_error_master_alloc:
+	spi_master_put(master);
+	return status;
+}
+
+int register_spi_removed_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&removed_notifier_list, nb);
+}
+EXPORT_SYMBOL(register_spi_removed_notifier);
+
+static int asr_spi_remove(struct platform_device *pdev)
+{
+	struct spi_driver_data *drv_data = platform_get_drvdata(pdev);
+	blocking_notifier_call_chain(&removed_notifier_list, 0, "removing");
+
+	if (!drv_data)
+		return 0;
+
+	pm_runtime_get_sync(&pdev->dev);
+
+	/* Disable the SSP at the peripheral and SOC level */
+	asr_spi_write(drv_data, TOP_CTRL, 0);
+	asr_spi_write(drv_data, FIFO_CTRL, 0); /* whether need this line? */
+
+	clk_disable_unprepare(drv_data->clk);
+
+	/* Release DMA */
+	if (drv_data->master_info->enable_dma)
+		asr_spi_dma_release(drv_data);
+
+	pm_runtime_put_noidle(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
+	/* Release IRQ */
+	free_irq(drv_data->irq, drv_data);
+
+	deinit_dvfm_constraint(drv_data);
+	return 0;
+}
+
+static void asr_spi_shutdown(struct platform_device *pdev)
+{
+	int status = 0;
+
+	if ((status = asr_spi_remove(pdev)) != 0)
+		dev_err(&pdev->dev, "shutdown failed with %d\n", status);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int asr_spi_suspend(struct device *dev)
+{
+	struct spi_driver_data *drv_data = dev_get_drvdata(dev);
+	int status = 0;
+
+	pm_runtime_get_sync(dev);
+	status = spi_master_suspend(drv_data->master);
+	if (status != 0)
+		return status;
+	asr_spi_write(drv_data, TOP_CTRL, 0);
+	asr_spi_write(drv_data, FIFO_CTRL, 0); /* whether need this line? */
+
+	status = pm_runtime_force_suspend(dev);
+
+	return status;
+}
+
+static int asr_spi_resume(struct device *dev)
+{
+	struct spi_driver_data *drv_data = dev_get_drvdata(dev);
+	int status = 0;
+
+	/* Enable the SSP clock */
+	status = pm_runtime_force_resume(dev);
+	if (status) {
+		dev_err(dev, "failed to resume pm_runtime (%d)\n", status);
+		return status;
+	}
+
+	/* Start the queue running */
+	status = spi_master_resume(drv_data->master);
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
+	if (status != 0) {
+		dev_err(dev, "problem starting queue (%d)\n", status);
+		return status;
+	}
+
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_PM
+static int asr_spi_runtime_suspend(struct device *dev)
+{
+	struct spi_driver_data *drv_data = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(drv_data->clk);
+	return 0;
+}
+
+static int asr_spi_runtime_resume(struct device *dev)
+{
+	struct spi_driver_data *drv_data = dev_get_drvdata(dev);
+
+	clk_prepare_enable(drv_data->clk);
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops asr_spi_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(asr_spi_suspend, asr_spi_resume)
+	SET_RUNTIME_PM_OPS(asr_spi_runtime_suspend,
+			   asr_spi_runtime_resume, NULL)
+};
+
+static struct platform_driver driver = {
+	.driver = {
+		.name	= "asr-spi",
+		.pm	= &asr_spi_pm_ops,
+		.of_match_table = asr_spi_dt_ids,
+	},
+	.probe = asr_spi_probe,
+	.remove = asr_spi_remove,
+	.shutdown = asr_spi_shutdown,
+};
+
+static int __init asr_spi_init(void)
+{
+	return platform_driver_register(&driver);
+}
+module_init(asr_spi_init);
+
+static void __exit asr_spi_exit(void)
+{
+	platform_driver_unregister(&driver);
+}
+module_exit(asr_spi_exit);