This patch adds support for GQSPI controller driver used by
Zynq Ultrascale+ MPSoC

Signed-off-by: Ranjit Waghmode <ranjit.waghm...@xilinx.com>
---
In v3, accommodating review comments given by Shubhrajyoti.

Changes in v3:
- Updated chip assert/de-assert timeout loop using jiffies
- Updated minor kernel doc comments
- Removed unwanted variable initialization in
  zynqmp_qspi_selectspimode() function
- In probe() updated goto statement to disable clocks if
  error occurs while registering interrupts.

Changes in v2:
- Replacing all readl/writel calls with respective
  zynqmp_gqspi_read/write wrappers
- Renamed function zynqmp_gqspi_selectflash to
  zynqmp_gqspi_selectslave
- Renamed formal parameters of the function zynqmp_gqspi_selectslave
- Updated all default cases of switch statements
- Removed typecasting of variable data in
  zynqmp_qspi_copy_read_data()
- Added return code check around clk_enable() calls
- Factored the clk_get_rate() API outside the loop
- Added generic fifo entry in zynqmp_qspi_chipselect() function to
  assure the CS assert and CS de-assert
- To assure an endianness, added memcpy() in
  zynqmp_qspi_filltxfifo() function
- For making sure that there is no HW setting during the
  transfer via setup(), Moved function call of
  zynqmp_qspi_setup_transfer() to
  zynqmp_qspi_filltxfifo() function.
- Set master->num_chipselect to default value instead of
  reading it via device-tree
---
---
 drivers/spi/Kconfig            |    6 +
 drivers/spi/Makefile           |    1 +
 drivers/spi/spi-zynqmp-gqspi.c | 1122 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 1129 insertions(+)
 create mode 100755 drivers/spi/spi-zynqmp-gqspi.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 72b0590..4406a85 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -610,6 +610,12 @@ config SPI_XTENSA_XTFPGA
          16 bit words in SPI mode 0, automatically asserting CS on transfer
          start and deasserting on end.

+config SPI_ZYNQMP_GQSPI
+       tristate "Xilinx ZynqMP GQSPI controller"
+       depends on SPI_MASTER
+       help
+         Enables Xilinx GQSPI controller driver for Zynq UltraScale+ MPSoC.
+
 config SPI_NUC900
        tristate "Nuvoton NUC900 series SPI"
        depends on ARCH_W90X900
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index d8cbf65..52db832 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -89,3 +89,4 @@ obj-$(CONFIG_SPI_TXX9)                        += spi-txx9.o
 obj-$(CONFIG_SPI_XCOMM)                += spi-xcomm.o
 obj-$(CONFIG_SPI_XILINX)               += spi-xilinx.o
 obj-$(CONFIG_SPI_XTENSA_XTFPGA)                += spi-xtensa-xtfpga.o
+obj-$(CONFIG_SPI_ZYNQMP_GQSPI)         += spi-zynqmp-gqspi.o
diff --git a/drivers/spi/spi-zynqmp-gqspi.c b/drivers/spi/spi-zynqmp-gqspi.c
new file mode 100755
index 0000000..87b20a5
--- /dev/null
+++ b/drivers/spi/spi-zynqmp-gqspi.c
@@ -0,0 +1,1122 @@
+/*
+ * Xilinx Zynq UltraScale+ MPSoC Quad-SPI (QSPI) controller driver
+ * (master mode only)
+ *
+ * Copyright (C) 2009 - 2015 Xilinx, Inc.
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+
+/* Generic QSPI register offsets */
+#define GQSPI_CONFIG_OFST              0x00000100
+#define GQSPI_ISR_OFST                 0x00000104
+#define GQSPI_IDR_OFST                 0x0000010C
+#define GQSPI_IER_OFST                 0x00000108
+#define GQSPI_IMASK_OFST               0x00000110
+#define GQSPI_EN_OFST                  0x00000114
+#define GQSPI_TXD_OFST                 0x0000011C
+#define GQSPI_RXD_OFST                 0x00000120
+#define GQSPI_TX_THRESHOLD_OFST                0x00000128
+#define GQSPI_RX_THRESHOLD_OFST                0x0000012C
+#define GQSPI_LPBK_DLY_ADJ_OFST                0x00000138
+#define GQSPI_GEN_FIFO_OFST            0x00000140
+#define GQSPI_SEL_OFST                 0x00000144
+#define GQSPI_GF_THRESHOLD_OFST                0x00000150
+#define GQSPI_FIFO_CTRL_OFST           0x0000014C
+#define GQSPI_QSPIDMA_DST_CTRL_OFST    0x0000080C
+#define GQSPI_QSPIDMA_DST_SIZE_OFST    0x00000804
+#define GQSPI_QSPIDMA_DST_STS_OFST     0x00000808
+#define GQSPI_QSPIDMA_DST_I_STS_OFST   0x00000814
+#define GQSPI_QSPIDMA_DST_I_EN_OFST    0x00000818
+#define GQSPI_QSPIDMA_DST_I_DIS_OFST   0x0000081C
+#define GQSPI_QSPIDMA_DST_I_MASK_OFST  0x00000820
+#define GQSPI_QSPIDMA_DST_ADDR_OFST    0x00000800
+#define GQSPI_QSPIDMA_DST_ADDR_MSB_OFST 0x00000828
+
+/* GQSPI register bit masks */
+#define GQSPI_SEL_MASK                         0x00000001
+#define GQSPI_EN_MASK                          0x00000001
+#define GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK       0x00000020
+#define GQSPI_ISR_WR_TO_CLR_MASK               0x00000002
+#define GQSPI_IDR_ALL_MASK                     0x00000FBE
+#define GQSPI_CFG_MODE_EN_MASK                 0xC0000000
+#define GQSPI_CFG_GEN_FIFO_START_MODE_MASK     0x20000000
+#define GQSPI_CFG_ENDIAN_MASK                  0x04000000
+#define GQSPI_CFG_EN_POLL_TO_MASK              0x00100000
+#define GQSPI_CFG_WP_HOLD_MASK                 0x00080000
+#define GQSPI_CFG_BAUD_RATE_DIV_MASK           0x00000038
+#define GQSPI_CFG_CLK_PHA_MASK                 0x00000004
+#define GQSPI_CFG_CLK_POL_MASK                 0x00000002
+#define GQSPI_CFG_START_GEN_FIFO_MASK          0x10000000
+#define GQSPI_GENFIFO_IMM_DATA_MASK            0x000000FF
+#define GQSPI_GENFIFO_DATA_XFER                        0x00000100
+#define GQSPI_GENFIFO_EXP                      0x00000200
+#define GQSPI_GENFIFO_MODE_SPI                 0x00000400
+#define GQSPI_GENFIFO_MODE_DUALSPI             0x00000800
+#define GQSPI_GENFIFO_MODE_QUADSPI             0x00000C00
+#define GQSPI_GENFIFO_MODE_MASK                        0x00000C00
+#define GQSPI_GENFIFO_CS_LOWER                 0x00001000
+#define GQSPI_GENFIFO_CS_UPPER                 0x00002000
+#define GQSPI_GENFIFO_BUS_LOWER                        0x00004000
+#define GQSPI_GENFIFO_BUS_UPPER                        0x00008000
+#define GQSPI_GENFIFO_BUS_BOTH                 0x0000C000
+#define GQSPI_GENFIFO_BUS_MASK                 0x0000C000
+#define GQSPI_GENFIFO_TX                       0x00010000
+#define GQSPI_GENFIFO_RX                       0x00020000
+#define GQSPI_GENFIFO_STRIPE                   0x00040000
+#define GQSPI_GENFIFO_POLL                     0x00080000
+#define GQSPI_GENFIFO_EXP_START                        0x00000100
+#define GQSPI_FIFO_CTRL_RST_RX_FIFO_MASK       0x00000004
+#define GQSPI_FIFO_CTRL_RST_TX_FIFO_MASK       0x00000002
+#define GQSPI_FIFO_CTRL_RST_GEN_FIFO_MASK      0x00000001
+#define GQSPI_ISR_RXEMPTY_MASK                 0x00000800
+#define GQSPI_ISR_GENFIFOFULL_MASK             0x00000400
+#define GQSPI_ISR_GENFIFONOT_FULL_MASK         0x00000200
+#define GQSPI_ISR_TXEMPTY_MASK                 0x00000100
+#define GQSPI_ISR_GENFIFOEMPTY_MASK            0x00000080
+#define GQSPI_ISR_RXFULL_MASK                  0x00000020
+#define GQSPI_ISR_RXNEMPTY_MASK                        0x00000010
+#define GQSPI_ISR_TXFULL_MASK                  0x00000008
+#define GQSPI_ISR_TXNOT_FULL_MASK              0x00000004
+#define GQSPI_ISR_POLL_TIME_EXPIRE_MASK                0x00000002
+#define GQSPI_IER_TXNOT_FULL_MASK              0x00000004
+#define GQSPI_IER_RXEMPTY_MASK                 0x00000800
+#define GQSPI_IER_POLL_TIME_EXPIRE_MASK                0x00000002
+#define GQSPI_IER_RXNEMPTY_MASK                        0x00000010
+#define GQSPI_IER_GENFIFOEMPTY_MASK            0x00000080
+#define GQSPI_IER_TXEMPTY_MASK                 0x00000100
+#define GQSPI_QSPIDMA_DST_INTR_ALL_MASK                0x000000FE
+#define GQSPI_QSPIDMA_DST_STS_WTC              0x0000E000
+#define GQSPI_CFG_MODE_EN_DMA_MASK             0x80000000
+#define GQSPI_ISR_IDR_MASK                     0x00000994
+#define GQSPI_QSPIDMA_DST_I_EN_DONE_MASK       0x00000002
+#define GQSPI_QSPIDMA_DST_I_STS_DONE_MASK      0x00000002
+#define GQSPI_IRQ_MASK                         0x00000980
+
+#define GQSPI_CFG_BAUD_RATE_DIV_SHIFT          3
+#define GQSPI_GENFIFO_CS_SETUP                 0x4
+#define GQSPI_GENFIFO_CS_HOLD                  0x3
+#define GQSPI_TXD_DEPTH                                64
+#define GQSPI_RX_FIFO_THRESHOLD                        32
+#define GQSPI_RX_FIFO_FILL     (GQSPI_RX_FIFO_THRESHOLD * 4)
+#define GQSPI_TX_FIFO_THRESHOLD_RESET_VAL      32
+#define GQSPI_TX_FIFO_FILL     (GQSPI_TXD_DEPTH -\
+                               GQSPI_TX_FIFO_THRESHOLD_RESET_VAL)
+#define GQSPI_GEN_FIFO_THRESHOLD_RESET_VAL     0X10
+#define GQSPI_QSPIDMA_DST_CTRL_RESET_VAL       0x803FFA00
+#define GQSPI_SELECT_FLASH_CS_LOWER            0x1
+#define GQSPI_SELECT_FLASH_CS_UPPER            0x2
+#define GQSPI_SELECT_FLASH_CS_BOTH             0x3
+#define GQSPI_SELECT_FLASH_BUS_LOWER           0x1
+#define GQSPI_SELECT_FLASH_BUS_UPPER           0x2
+#define GQSPI_SELECT_FLASH_BUS_BOTH            0x3
+#define GQSPI_BAUD_DIV_MAX     7       /* Baud rate divisor maximum */
+#define GQSPI_BAUD_DIV_SHIFT   2       /* Baud rate divisor shift */
+#define GQSPI_SELECT_MODE_SPI          0x1
+#define GQSPI_SELECT_MODE_DUALSPI      0x2
+#define GQSPI_SELECT_MODE_QUADSPI      0x4
+#define GQSPI_DMA_UNALIGN              0x3
+#define GQSPI_DEFAULT_NUM_CS   1       /* Default number of chip selects */
+
+enum mode_type {GQSPI_MODE_IO, GQSPI_MODE_DMA};
+
+/**
+ * struct zynqmp_qspi - Defines qspi driver instance
+ * @regs:              Virtual address of the QSPI controller registers
+ * @refclk:            Pointer to the peripheral clock
+ * @pclk:              Pointer to the APB clock
+ * @irq:               IRQ number
+ * @dev:               Pointer to struct device
+ * @txbuf:             Pointer to the TX buffer
+ * @rxbuf:             Pointer to the RX buffer
+ * @bytes_to_transfer: Number of bytes left to transfer
+ * @bytes_to_receive:  Number of bytes left to receive
+ * @genfifocs:         Used for chip select
+ * @genfifobus:                Used to select the upper or lower bus
+ * @dma_rx_bytes:      Remaining bytes to receive by DMA mode
+ * @dma_addr:          DMA address after mapping the kernel buffer
+ * @genfifoentry:      Used for storing the genfifoentry instruction.
+ * @mode:              Defines the mode in which QSPI is operating
+ */
+struct zynqmp_qspi {
+       void __iomem *regs;
+       struct clk *refclk;
+       struct clk *pclk;
+       int irq;
+       struct device *dev;
+       const void *txbuf;
+       void *rxbuf;
+       int bytes_to_transfer;
+       int bytes_to_receive;
+       u32 genfifocs;
+       u32 genfifobus;
+       u32 dma_rx_bytes;
+       dma_addr_t dma_addr;
+       u32 genfifoentry;
+       enum mode_type mode;
+};
+
+/**
+ * zynqmp_gqspi_read:  For GQSPI controller read operation
+ * @xqspi:     Pointer to the zynqmp_qspi structure
+ * @offset:    Offset from where to read
+ */
+static u32 zynqmp_gqspi_read(struct zynqmp_qspi *xqspi, u32 offset)
+{
+       return readl_relaxed(xqspi->regs + offset);
+}
+
+/**
+ * zynqmp_gqspi_write: For GQSPI controller write operation
+ * @xqspi:     Pointer to the zynqmp_qspi structure
+ * @offset:    Offset where to write
+ * @val:       Value to be written
+ */
+static inline void zynqmp_gqspi_write(struct zynqmp_qspi *xqspi, u32 offset,
+                                     u32 val)
+{
+       writel_relaxed(val, (xqspi->regs + offset));
+}
+
+/**
+ * zynqmp_gqspi_selectslave:   For selection of slave device
+ * @instanceptr:       Pointer to the zynqmp_qspi structure
+ * @flashcs:   For chip select
+ * @flashbus:  To check which bus is selected- upper or lower
+ */
+static void zynqmp_gqspi_selectslave(struct zynqmp_qspi *instanceptr,
+                                    u8 slavecs, u8 slavebus)
+{
+       /*
+        * Bus and CS lines selected here will be updated in the instance and
+        * used for subsequent GENFIFO entries during transfer.
+        */
+
+       /* Choose slave select line */
+       switch (slavecs) {
+       case GQSPI_SELECT_FLASH_CS_BOTH:
+               instanceptr->genfifocs = GQSPI_GENFIFO_CS_LOWER |
+                       GQSPI_GENFIFO_CS_UPPER;
+       case GQSPI_SELECT_FLASH_CS_UPPER:
+               instanceptr->genfifocs = GQSPI_GENFIFO_CS_UPPER;
+               break;
+       case GQSPI_SELECT_FLASH_CS_LOWER:
+               instanceptr->genfifocs = GQSPI_GENFIFO_CS_LOWER;
+               break;
+       default:
+               dev_warn(instanceptr->dev, "Invalid slave select\n");
+       }
+
+       /* Choose the bus */
+       switch (slavebus) {
+       case GQSPI_SELECT_FLASH_BUS_BOTH:
+               instanceptr->genfifobus = GQSPI_GENFIFO_BUS_LOWER |
+                       GQSPI_GENFIFO_BUS_UPPER;
+               break;
+       case GQSPI_SELECT_FLASH_BUS_UPPER:
+               instanceptr->genfifobus = GQSPI_GENFIFO_BUS_UPPER;
+               break;
+       case GQSPI_SELECT_FLASH_BUS_LOWER:
+               instanceptr->genfifobus = GQSPI_GENFIFO_BUS_LOWER;
+               break;
+       default:
+               dev_warn(instanceptr->dev, "Invalid slave bus\n");
+       }
+}
+
+/**
+ * zynqmp_qspi_init_hw:        Initialize the hardware
+ * @xqspi:     Pointer to the zynqmp_qspi structure
+ *
+ * The default settings of the QSPI controller's configurable parameters on
+ * reset are
+ *     - Master mode
+ *     - TX threshold set to 1
+ *     - RX threshold set to 1
+ *     - Flash memory interface mode enabled
+ * This function performs the following actions
+ *     - Disable and clear all the interrupts
+ *     - Enable manual slave select
+ *     - Enable manual start
+ *     - Deselect all the chip select lines
+ *     - Set the little endian mode of TX FIFO and
+ *     - Enable the QSPI controller
+ */
+static void zynqmp_qspi_init_hw(struct zynqmp_qspi *xqspi)
+{
+       u32 config_reg;
+
+       /* Select the GQSPI mode */
+       zynqmp_gqspi_write(xqspi, GQSPI_SEL_OFST, GQSPI_SEL_MASK);
+       /* Clear and disable interrupts */
+       zynqmp_gqspi_write(xqspi, GQSPI_ISR_OFST,
+                          zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST) |
+                          GQSPI_ISR_WR_TO_CLR_MASK);
+       /* Clear the DMA STS */
+       zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST,
+                          zynqmp_gqspi_read(xqspi,
+                                            GQSPI_QSPIDMA_DST_I_STS_OFST));
+       zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_STS_OFST,
+                          zynqmp_gqspi_read(xqspi,
+                                            GQSPI_QSPIDMA_DST_STS_OFST) |
+                                            GQSPI_QSPIDMA_DST_STS_WTC);
+       zynqmp_gqspi_write(xqspi, GQSPI_IDR_OFST, GQSPI_IDR_ALL_MASK);
+       zynqmp_gqspi_write(xqspi,
+                          GQSPI_QSPIDMA_DST_I_DIS_OFST,
+                          GQSPI_QSPIDMA_DST_INTR_ALL_MASK);
+       /* Disable the GQSPI */
+       zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
+       config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
+       config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
+       /* Manual start */
+       config_reg |= GQSPI_CFG_GEN_FIFO_START_MODE_MASK;
+       /* Little endian by default */
+       config_reg &= ~GQSPI_CFG_ENDIAN_MASK;
+       /* Disable poll time out */
+       config_reg &= ~GQSPI_CFG_EN_POLL_TO_MASK;
+       /* Set hold bit */
+       config_reg |= GQSPI_CFG_WP_HOLD_MASK;
+       /* Clear pre-scalar by default */
+       config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
+       /* CPHA 0 */
+       config_reg &= ~GQSPI_CFG_CLK_PHA_MASK;
+       /* CPOL 0 */
+       config_reg &= ~GQSPI_CFG_CLK_POL_MASK;
+       zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
+
+       /* Clear the TX and RX FIFO */
+       zynqmp_gqspi_write(xqspi, GQSPI_FIFO_CTRL_OFST,
+                          GQSPI_FIFO_CTRL_RST_RX_FIFO_MASK |
+                          GQSPI_FIFO_CTRL_RST_TX_FIFO_MASK |
+                          GQSPI_FIFO_CTRL_RST_GEN_FIFO_MASK);
+       /* Set by default to allow for high frequencies */
+       zynqmp_gqspi_write(xqspi, GQSPI_LPBK_DLY_ADJ_OFST,
+                          zynqmp_gqspi_read(xqspi, GQSPI_LPBK_DLY_ADJ_OFST) |
+                          GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK);
+       /* Reset thresholds */
+       zynqmp_gqspi_write(xqspi, GQSPI_TX_THRESHOLD_OFST,
+                          GQSPI_TX_FIFO_THRESHOLD_RESET_VAL);
+       zynqmp_gqspi_write(xqspi, GQSPI_RX_THRESHOLD_OFST,
+                          GQSPI_RX_FIFO_THRESHOLD);
+       zynqmp_gqspi_write(xqspi, GQSPI_GF_THRESHOLD_OFST,
+                          GQSPI_GEN_FIFO_THRESHOLD_RESET_VAL);
+       zynqmp_gqspi_selectslave(xqspi,
+                                GQSPI_SELECT_FLASH_CS_LOWER,
+                                GQSPI_SELECT_FLASH_BUS_LOWER);
+       /* Initialize DMA */
+       zynqmp_gqspi_write(xqspi,
+                       GQSPI_QSPIDMA_DST_CTRL_OFST,
+                       GQSPI_QSPIDMA_DST_CTRL_RESET_VAL);
+
+       /* Enable the GQSPI */
+       zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
+}
+
+/**
+ * zynqmp_qspi_copy_read_data: Copy data to RX buffer
+ * @xqspi:     Pointer to the zynqmp_qspi structure
+ * @data:      The variable where data is stored
+ * @size:      Number of bytes to be copied from data to RX buffer
+ */
+static void zynqmp_qspi_copy_read_data(struct zynqmp_qspi *xqspi,
+                                      ulong data, u8 size)
+{
+       memcpy(xqspi->rxbuf, &data, size);
+       xqspi->rxbuf += size;
+       xqspi->bytes_to_receive -= size;
+}
+
+/**
+ * zynqmp_prepare_transfer_hardware:   Prepares hardware for transfer.
+ * @master:    Pointer to the spi_master structure which provides
+ *             information about the controller.
+ *
+ * This function enables SPI master controller.
+ *
+ * Return:     0 on success; error value otherwise
+ */
+static int zynqmp_prepare_transfer_hardware(struct spi_master *master)
+{
+       struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+       int ret;
+
+       ret = clk_enable(xqspi->refclk);
+       if (ret)
+               goto clk_err;
+
+       ret = clk_enable(xqspi->pclk);
+       if (ret)
+               goto clk_err;
+
+       zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
+       return 0;
+clk_err:
+       return ret;
+}
+
+/**
+ * zynqmp_unprepare_transfer_hardware: Relaxes hardware after transfer
+ * @master:    Pointer to the spi_master structure which provides
+ *             information about the controller.
+ *
+ * This function disables the SPI master controller.
+ *
+ * Return:     Always 0
+ */
+static int zynqmp_unprepare_transfer_hardware(struct spi_master *master)
+{
+       struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+
+       zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
+       clk_disable(xqspi->refclk);
+       clk_disable(xqspi->pclk);
+       return 0;
+}
+
+/**
+ * zynqmp_qspi_chipselect:     Select or deselect the chip select line
+ * @qspi:      Pointer to the spi_device structure
+ * @is_high:   Select(0) or deselect (1) the chip select line
+ */
+static void zynqmp_qspi_chipselect(struct spi_device *qspi, bool is_high)
+{
+       struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master);
+       ulong timeout;
+       u32 genfifoentry = 0x0, statusreg;
+
+       genfifoentry |= GQSPI_GENFIFO_MODE_SPI;
+       genfifoentry |= xqspi->genfifobus;
+
+       if (!is_high) {
+               genfifoentry |= xqspi->genfifocs;
+               genfifoentry |= GQSPI_GENFIFO_CS_SETUP;
+       } else {
+               genfifoentry |= GQSPI_GENFIFO_CS_HOLD;
+       }
+
+       zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
+
+       /* Dummy generic FIFO entry */
+       zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
+
+       /* Manually start the generic FIFO command */
+       zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
+                       zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
+                       GQSPI_CFG_START_GEN_FIFO_MASK);
+
+       timeout = jiffies + msecs_to_jiffies(1000);
+
+       /* Wait until the generic FIFO command is empty */
+       do {
+               statusreg = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
+
+               if ((statusreg & GQSPI_ISR_GENFIFOEMPTY_MASK) &&
+                       (statusreg & GQSPI_ISR_TXEMPTY_MASK))
+                       break;
+               else
+                       cpu_relax();
+       } while (!time_after_eq(jiffies, timeout));
+
+       if (time_after_eq(jiffies, timeout))
+               dev_err(xqspi->dev, "Chip select timed out\n");
+}
+
+/**
+ * zynqmp_qspi_setup_transfer: Configure QSPI controller for specified
+ *                             transfer
+ * @qspi:      Pointer to the spi_device structure
+ * @transfer:  Pointer to the spi_transfer structure which provides
+ *             information about next transfer setup parameters
+ *
+ * Sets the operational mode of QSPI controller for the next QSPI transfer and
+ * sets the requested clock frequency.
+ *
+ * Return:     Always 0
+ *
+ * Note:
+ *     If the requested frequency is not an exact match with what can be
+ *     obtained using the pre-scalar value, the driver sets the clock
+ *     frequency which is lower than the requested frequency (maximum lower)
+ *     for the transfer.
+ *
+ *     If the requested frequency is higher or lower than that is supported
+ *     by the QSPI controller the driver will set the highest or lowest
+ *     frequency supported by controller.
+ */
+static int zynqmp_qspi_setup_transfer(struct spi_device *qspi,
+                                     struct spi_transfer *transfer)
+{
+       struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master);
+       ulong clk_rate;
+       u32 config_reg, req_hz, baud_rate_val = 0;
+
+       if (transfer)
+               req_hz = transfer->speed_hz;
+       else
+               req_hz = qspi->max_speed_hz;
+
+       /* Set the clock frequency */
+       /* If req_hz == 0, default to lowest speed */
+       clk_rate = clk_get_rate(xqspi->refclk);
+
+       while ((baud_rate_val < GQSPI_BAUD_DIV_MAX) &&
+              (clk_rate /
+               (GQSPI_BAUD_DIV_SHIFT << baud_rate_val)) > req_hz)
+               baud_rate_val++;
+
+       config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
+
+       /* Set the QSPI clock phase and clock polarity */
+       config_reg &= (~GQSPI_CFG_CLK_PHA_MASK) & (~GQSPI_CFG_CLK_POL_MASK);
+
+       if (qspi->mode & SPI_CPHA)
+               config_reg |= GQSPI_CFG_CLK_PHA_MASK;
+       if (qspi->mode & SPI_CPOL)
+               config_reg |= GQSPI_CFG_CLK_POL_MASK;
+
+       config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
+       config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT);
+       zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
+       return 0;
+}
+
+/**
+ * zynqmp_qspi_setup:  Configure the QSPI controller
+ * @qspi:      Pointer to the spi_device structure
+ *
+ * Sets the operational mode of QSPI controller for the next QSPI transfer,
+ * baud rate and divisor value to setup the requested qspi clock.
+ *
+ * Return:     0 on success; error value otherwise.
+ */
+static int zynqmp_qspi_setup(struct spi_device *qspi)
+{
+       if (qspi->master->busy)
+               return -EBUSY;
+       return 0;
+}
+
+/**
+ * zynqmp_qspi_filltxfifo:     Fills the TX FIFO as long as there is room in
+ *                             the FIFO or the bytes required to be
+ *                             transmitted.
+ * @xqspi:     Pointer to the zynqmp_qspi structure
+ * @size:      Number of bytes to be copied from TX buffer to TX FIFO
+ */
+static void zynqmp_qspi_filltxfifo(struct zynqmp_qspi *xqspi, int size)
+{
+       u32 count = 0, intermediate;
+
+       while ((xqspi->bytes_to_transfer > 0) && (count < size)) {
+               memcpy(&intermediate, xqspi->txbuf, 4);
+               zynqmp_gqspi_write(xqspi, GQSPI_TXD_OFST, intermediate);
+
+               if (xqspi->bytes_to_transfer >= 4) {
+                       xqspi->txbuf += 4;
+                       xqspi->bytes_to_transfer -= 4;
+               } else {
+                       xqspi->txbuf += xqspi->bytes_to_transfer;
+                       xqspi->bytes_to_transfer = 0;
+               }
+               count++;
+       }
+}
+
+/**
+ * zynqmp_qspi_readrxfifo:     Fills the RX FIFO as long as there is room in
+ *                             the FIFO.
+ * @xqspi:     Pointer to the zynqmp_qspi structure
+ * @size:      Number of bytes to be copied from RX buffer to RX FIFO
+ */
+static void zynqmp_qspi_readrxfifo(struct zynqmp_qspi *xqspi, u32 size)
+{
+       ulong data;
+       int count = 0;
+
+       while ((count < size) && (xqspi->bytes_to_receive > 0)) {
+               if (xqspi->bytes_to_receive >= 4) {
+                       (*(u32 *) xqspi->rxbuf) =
+                       zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST);
+                       xqspi->rxbuf += 4;
+                       xqspi->bytes_to_receive -= 4;
+                       count += 4;
+               } else {
+                       data = zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST);
+                       count += xqspi->bytes_to_receive;
+                       zynqmp_qspi_copy_read_data(xqspi, data,
+                                                  xqspi->bytes_to_receive);
+                       xqspi->bytes_to_receive = 0;
+               }
+       }
+}
+
+/**
+ * zynqmp_process_dma_irq:     Handler for DMA done interrupt of QSPI
+ *                             controller
+ * @xqspi:     zynqmp_qspi instance pointer
+ *
+ * This function handles DMA interrupt only.
+ */
+static void zynqmp_process_dma_irq(struct zynqmp_qspi *xqspi)
+{
+       u32 config_reg, genfifoentry;
+
+       dma_unmap_single(xqspi->dev, xqspi->dma_addr,
+                               xqspi->dma_rx_bytes, DMA_FROM_DEVICE);
+       xqspi->rxbuf += xqspi->dma_rx_bytes;
+       xqspi->bytes_to_receive -= xqspi->dma_rx_bytes;
+       xqspi->dma_rx_bytes = 0;
+
+       /* Disabling the DMA interrupts */
+       zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_DIS_OFST,
+                                       GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
+
+       if (xqspi->bytes_to_receive > 0) {
+               /* Switch to IO mode,for remaining bytes to receive */
+               config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
+               config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
+               zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
+
+               /* Initiate the transfer of remaining bytes */
+               genfifoentry = xqspi->genfifoentry;
+               genfifoentry |= xqspi->bytes_to_receive;
+               zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
+
+               /* Dummy generic FIFO entry */
+               zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
+
+               /* Manual start */
+               zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
+                       (zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
+                       GQSPI_CFG_START_GEN_FIFO_MASK));
+
+               /* Enable the RX interrupts for IO mode */
+               zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
+                               GQSPI_IER_GENFIFOEMPTY_MASK |
+                               GQSPI_IER_RXNEMPTY_MASK |
+                               GQSPI_IER_RXEMPTY_MASK);
+       }
+}
+
+/**
+ * zynqmp_qspi_irq:    Interrupt service routine of the QSPI controller
+ * @irq:       IRQ number
+ * @dev_id:    Pointer to the xqspi structure
+ *
+ * This function handles TX empty only.
+ * On TX empty interrupt this function reads the received data from RX FIFO
+ * and fills the TX FIFO if there is any data remaining to be transferred.
+ *
+ * Return:     IRQ_HANDLED when interrupt is handled
+ *             IRQ_NONE otherwise.
+ */
+static irqreturn_t zynqmp_qspi_irq(int irq, void *dev_id)
+{
+       struct spi_master *master = dev_id;
+       struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+       int ret = IRQ_NONE;
+       u32 status, mask, dma_status = 0;
+
+       status = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
+       zynqmp_gqspi_write(xqspi, GQSPI_ISR_OFST, status);
+       mask = (status & ~(zynqmp_gqspi_read(xqspi, GQSPI_IMASK_OFST)));
+
+       /* Read and clear DMA status */
+       if (xqspi->mode == GQSPI_MODE_DMA) {
+               dma_status =
+                       zynqmp_gqspi_read(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST);
+               zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST,
+                                                               dma_status);
+       }
+
+       if (mask & GQSPI_ISR_TXNOT_FULL_MASK) {
+               zynqmp_qspi_filltxfifo(xqspi, GQSPI_TX_FIFO_FILL);
+               ret = IRQ_HANDLED;
+       }
+
+       if (dma_status & GQSPI_QSPIDMA_DST_I_STS_DONE_MASK) {
+               zynqmp_process_dma_irq(xqspi);
+               ret = IRQ_HANDLED;
+       } else if (!(mask & GQSPI_IER_RXEMPTY_MASK) &&
+                       (mask & GQSPI_IER_GENFIFOEMPTY_MASK)) {
+               zynqmp_qspi_readrxfifo(xqspi, GQSPI_RX_FIFO_FILL);
+               ret = IRQ_HANDLED;
+       }
+
+       if ((xqspi->bytes_to_receive == 0) && (xqspi->bytes_to_transfer == 0)
+                       && ((status & GQSPI_IRQ_MASK) == GQSPI_IRQ_MASK)) {
+               zynqmp_gqspi_write(xqspi, GQSPI_IDR_OFST, GQSPI_ISR_IDR_MASK);
+               spi_finalize_current_transfer(master);
+               ret = IRQ_HANDLED;
+       }
+       return ret;
+}
+
+/**
+ * zynqmp_qspi_selectspimode:  Selects SPI mode - x1 or x2 or x4.
+ * @xqspi:     xqspi is a pointer to the GQSPI instance
+ * @spimode:   spimode - SPI or DUAL or QUAD.
+ * Return:     Mask to set desired SPI mode in GENFIFO entry.
+ */
+static inline u32 zynqmp_qspi_selectspimode(struct zynqmp_qspi *xqspi,
+                                               u8 spimode)
+{
+       u32 mask = 0;
+
+       switch (spimode) {
+       case GQSPI_SELECT_MODE_DUALSPI:
+               mask = GQSPI_GENFIFO_MODE_DUALSPI;
+               break;
+       case GQSPI_SELECT_MODE_QUADSPI:
+               mask = GQSPI_GENFIFO_MODE_QUADSPI;
+               break;
+       case GQSPI_SELECT_MODE_SPI:
+               mask = GQSPI_GENFIFO_MODE_SPI;
+               break;
+       default:
+               dev_warn(xqspi->dev, "Invalid SPI mode\n");
+       }
+
+       return mask;
+}
+
+/**
+ * zynq_qspi_setuprxdma:       This function sets up the RX DMA operation
+ * @xqspi:     xqspi is a pointer to the GQSPI instance.
+ */
+static void zynq_qspi_setuprxdma(struct zynqmp_qspi *xqspi)
+{
+       u32 rx_bytes, rx_rem, config_reg;
+       dma_addr_t addr;
+       u64 dma_align =  (u64)(uintptr_t)xqspi->rxbuf;
+
+       if ((xqspi->bytes_to_receive < 8) ||
+               ((dma_align & GQSPI_DMA_UNALIGN) != 0x0)) {
+               /* Setting to IO mode */
+               config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
+               config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
+               zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
+               xqspi->mode = GQSPI_MODE_IO;
+               xqspi->dma_rx_bytes = 0;
+               return;
+       }
+
+       rx_rem = xqspi->bytes_to_receive % 4;
+       rx_bytes = (xqspi->bytes_to_receive - rx_rem);
+
+       addr = dma_map_single(xqspi->dev, (void *)xqspi->rxbuf,
+                                               rx_bytes, DMA_FROM_DEVICE);
+       if (dma_mapping_error(xqspi->dev, addr))
+               dev_err(xqspi->dev, "ERR:rxdma:memory not mapped\n");
+
+       xqspi->dma_rx_bytes = rx_bytes;
+       xqspi->dma_addr = addr;
+       zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_OFST,
+                               (u32)(addr & 0xffffffff));
+       addr = ((addr >> 16) >> 16);
+       zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_MSB_OFST,
+                               ((u32)addr) & 0xfff);
+
+       /* Enabling the DMA mode */
+       config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
+       config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
+       config_reg |= GQSPI_CFG_MODE_EN_DMA_MASK;
+       zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
+
+       /* Switch to DMA mode */
+       xqspi->mode = GQSPI_MODE_DMA;
+
+       /* Write the number of bytes to transfer */
+       zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_SIZE_OFST, rx_bytes);
+}
+
+/**
+ * zynqmp_qspi_txrxsetup:      This function checks the TX/RX buffers in
+ *                             the transfer and sets up the GENFIFO entries,
+ *                             TX FIFO as required.
+ * @xqspi:     xqspi is a pointer to the GQSPI instance.
+ * @transfer:  It is a pointer to the structure containing transfer data.
+ * @genfifoentry:      genfifoentry is pointer to the variable in which
+ *                     GENFIFO mask is returned to calling function
+ */
+static void zynqmp_qspi_txrxsetup(struct zynqmp_qspi *xqspi,
+                                 struct spi_transfer *transfer,
+                                 u32 *genfifoentry)
+{
+       u32 config_reg;
+
+       /* Transmit */
+       if ((xqspi->txbuf != NULL) && (xqspi->rxbuf == NULL)) {
+               /* Setup data to be TXed */
+               *genfifoentry &= ~GQSPI_GENFIFO_RX;
+               *genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
+               *genfifoentry |= GQSPI_GENFIFO_TX;
+               *genfifoentry |=
+                       zynqmp_qspi_selectspimode(xqspi, transfer->tx_nbits);
+               xqspi->bytes_to_transfer = transfer->len;
+               if (xqspi->mode == GQSPI_MODE_DMA) {
+                       config_reg = zynqmp_gqspi_read(xqspi,
+                                                       GQSPI_CONFIG_OFST);
+                       config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
+                       zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
+                                                               config_reg);
+                       xqspi->mode = GQSPI_MODE_IO;
+               }
+               zynqmp_qspi_filltxfifo(xqspi, GQSPI_TXD_DEPTH);
+               /* Discard RX data */
+               xqspi->bytes_to_receive = 0;
+       } else if ((xqspi->txbuf == NULL) && (xqspi->rxbuf != NULL)) {
+               /* Receive */
+
+               /* TX auto fill */
+               *genfifoentry &= ~GQSPI_GENFIFO_TX;
+               /* Setup RX */
+               *genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
+               *genfifoentry |= GQSPI_GENFIFO_RX;
+               *genfifoentry |=
+                       zynqmp_qspi_selectspimode(xqspi, transfer->rx_nbits);
+               xqspi->bytes_to_transfer = 0;
+               xqspi->bytes_to_receive = transfer->len;
+               zynq_qspi_setuprxdma(xqspi);
+       }
+}
+
+/**
+ * zynqmp_qspi_start_transfer: Initiates the QSPI transfer
+ * @master:    Pointer to the spi_master structure which provides
+ *             information about the controller.
+ * @qspi:      Pointer to the spi_device structure
+ * @transfer:  Pointer to the spi_transfer structure which provide information
+ *             about next transfer parameters
+ *
+ * This function fills the TX FIFO, starts the QSPI transfer, and waits for the
+ * transfer to be completed.
+ *
+ * Return:     Number of bytes transferred in the last transfer
+ */
+static int zynqmp_qspi_start_transfer(struct spi_master *master,
+                                     struct spi_device *qspi,
+                                     struct spi_transfer *transfer)
+{
+       struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+       u32 genfifoentry = 0x0, transfer_len;
+
+       xqspi->txbuf = transfer->tx_buf;
+       xqspi->rxbuf = transfer->rx_buf;
+
+       zynqmp_qspi_setup_transfer(qspi, transfer);
+
+       genfifoentry |= xqspi->genfifocs;
+       genfifoentry |= xqspi->genfifobus;
+
+       zynqmp_qspi_txrxsetup(xqspi, transfer, &genfifoentry);
+
+       if (xqspi->mode == GQSPI_MODE_DMA)
+               transfer_len = xqspi->dma_rx_bytes;
+       else
+               transfer_len = transfer->len;
+
+       xqspi->genfifoentry = genfifoentry;
+       if ((transfer_len) < GQSPI_GENFIFO_IMM_DATA_MASK) {
+               genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
+               genfifoentry |= transfer_len;
+               zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
+       } else {
+               int tempcount = transfer_len;
+               u32 exponent = 8;       /* 2^8 = 256 */
+               u8 imm_data = tempcount & 0xFF;
+
+               tempcount &= ~(tempcount & 0xFF);
+               /* Immediate entry */
+               if (tempcount != 0) {
+                       /* Exponent entries */
+                       genfifoentry |= GQSPI_GENFIFO_EXP;
+                       while (tempcount != 0) {
+                               if (tempcount & GQSPI_GENFIFO_EXP_START) {
+                                       genfifoentry &=
+                                           ~GQSPI_GENFIFO_IMM_DATA_MASK;
+                                       genfifoentry |= exponent;
+                                       zynqmp_gqspi_write(xqspi,
+                                                          GQSPI_GEN_FIFO_OFST,
+                                                          genfifoentry);
+                               }
+                               tempcount = tempcount >> 1;
+                               exponent++;
+                       }
+               }
+               if (imm_data != 0) {
+                       genfifoentry &= ~GQSPI_GENFIFO_EXP;
+                       genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
+                       genfifoentry |= (u8) (imm_data & 0xFF);
+                       zynqmp_gqspi_write(xqspi,
+                                          GQSPI_GEN_FIFO_OFST, genfifoentry);
+               }
+       }
+
+       if ((xqspi->mode == GQSPI_MODE_IO) &&
+                       (xqspi->rxbuf != NULL)) {
+               /* Dummy generic FIFO entry */
+               zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
+       }
+
+       /* Since we are using manual mode */
+       zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
+                          zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
+                          GQSPI_CFG_START_GEN_FIFO_MASK);
+
+       if (xqspi->txbuf != NULL)
+               /* Enable interrupts for TX */
+               zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
+                                  GQSPI_IER_TXEMPTY_MASK |
+                                       GQSPI_IER_GENFIFOEMPTY_MASK |
+                                       GQSPI_IER_TXNOT_FULL_MASK);
+
+       if (xqspi->rxbuf != NULL) {
+               /* Enable interrupts for RX */
+               if (xqspi->mode == GQSPI_MODE_DMA) {
+                       /* Enable DMA interrupts */
+                       zynqmp_gqspi_write(xqspi,
+                                       GQSPI_QSPIDMA_DST_I_EN_OFST,
+                                       GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
+               } else {
+                       zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
+                                       GQSPI_IER_GENFIFOEMPTY_MASK |
+                                       GQSPI_IER_RXNEMPTY_MASK |
+                                       GQSPI_IER_RXEMPTY_MASK);
+               }
+       }
+
+       return transfer->len;
+}
+
+/**
+ * zynqmp_qspi_suspend:        Suspend method for the QSPI driver
+ * @_dev:      Address of the platform_device structure
+ *
+ * This function stops the QSPI driver queue and disables the QSPI controller
+ *
+ * Return:     Always 0
+ */
+static int __maybe_unused zynqmp_qspi_suspend(struct device *dev)
+{
+       struct platform_device *pdev = container_of(dev,
+                                                   struct platform_device,
+                                                   dev);
+       struct spi_master *master = platform_get_drvdata(pdev);
+
+       spi_master_suspend(master);
+
+       zynqmp_unprepare_transfer_hardware(master);
+
+       return 0;
+}
+
+/**
+ * zynqmp_qspi_resume: Resume method for the QSPI driver
+ * @dev:       Address of the platform_device structure
+ *
+ * The function starts the QSPI driver queue and initializes the QSPI
+ * controller
+ *
+ * Return:     0 on success; error value otherwise
+ */
+static int __maybe_unused zynqmp_qspi_resume(struct device *dev)
+{
+       struct platform_device *pdev = container_of(dev,
+                                                   struct platform_device,
+                                                   dev);
+       struct spi_master *master = platform_get_drvdata(pdev);
+       struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+       int ret = 0;
+
+       ret = clk_enable(xqspi->pclk);
+       if (ret) {
+               dev_err(dev, "Cannot enable APB clock.\n");
+               return ret;
+       }
+
+       ret = clk_enable(xqspi->refclk);
+       if (ret) {
+               dev_err(dev, "Cannot enable device clock.\n");
+               clk_disable(xqspi->pclk);
+               return ret;
+       }
+
+       spi_master_resume(master);
+
+       return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(zynqmp_qspi_dev_pm_ops, zynqmp_qspi_suspend,
+                        zynqmp_qspi_resume);
+
+/**
+ * zynqmp_qspi_probe:  Probe method for the QSPI driver
+ * @pdev:      Pointer to the platform_device structure
+ *
+ * This function initializes the driver data structures and the hardware.
+ *
+ * Return:     0 on success; error value otherwise
+ */
+static int zynqmp_qspi_probe(struct platform_device *pdev)
+{
+       int ret = 0;
+       struct spi_master *master;
+       struct zynqmp_qspi *xqspi;
+       struct resource *res;
+       struct device *dev = &pdev->dev;
+
+       master = spi_alloc_master(&pdev->dev, sizeof(*xqspi));
+       if (!master)
+               return -ENOMEM;
+
+       xqspi = spi_master_get_devdata(master);
+       master->dev.of_node = pdev->dev.of_node;
+       platform_set_drvdata(pdev, master);
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       xqspi->regs = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(xqspi->regs)) {
+               ret = PTR_ERR(xqspi->regs);
+               goto remove_master;
+       }
+
+       xqspi->dev = dev;
+       xqspi->pclk = devm_clk_get(&pdev->dev, "pclk");
+       if (IS_ERR(xqspi->pclk)) {
+               dev_err(dev, "pclk clock not found.\n");
+               ret = PTR_ERR(xqspi->pclk);
+               goto remove_master;
+       }
+
+       ret = clk_prepare_enable(xqspi->pclk);
+       if (ret) {
+               dev_err(dev, "Unable to enable APB clock.\n");
+               goto remove_master;
+       }
+
+       xqspi->refclk = devm_clk_get(&pdev->dev, "ref_clk");
+       if (IS_ERR(xqspi->refclk)) {
+               dev_err(dev, "ref_clk clock not found.\n");
+               ret = PTR_ERR(xqspi->refclk);
+               goto clk_dis_pclk;
+       }
+
+       ret = clk_prepare_enable(xqspi->refclk);
+       if (ret) {
+               dev_err(dev, "Unable to enable device clock.\n");
+               goto clk_dis_pclk;
+       }
+
+       /* QSPI controller initializations */
+       zynqmp_qspi_init_hw(xqspi);
+
+       xqspi->irq = platform_get_irq(pdev, 0);
+       if (xqspi->irq <= 0) {
+               ret = -ENXIO;
+               dev_err(dev, "irq resource not found\n");
+               goto clk_dis_all;
+       }
+       ret = devm_request_irq(&pdev->dev, xqspi->irq, zynqmp_qspi_irq,
+                              0, pdev->name, master);
+       if (ret != 0) {
+               ret = -ENXIO;
+               dev_err(dev, "request_irq failed\n");
+               goto clk_dis_all;
+       }
+
+       master->num_chipselect = GQSPI_DEFAULT_NUM_CS;
+
+       master->setup = zynqmp_qspi_setup;
+       master->set_cs = zynqmp_qspi_chipselect;
+       master->transfer_one = zynqmp_qspi_start_transfer;
+       master->prepare_transfer_hardware = zynqmp_prepare_transfer_hardware;
+       master->unprepare_transfer_hardware =
+                                       zynqmp_unprepare_transfer_hardware;
+       master->max_speed_hz = clk_get_rate(xqspi->refclk) / 2;
+       master->bits_per_word_mask = SPI_BPW_MASK(8);
+       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD |
+                           SPI_TX_DUAL | SPI_TX_QUAD;
+
+       if (master->dev.parent == NULL)
+               master->dev.parent = &master->dev;
+
+       ret = spi_register_master(master);
+       if (ret)
+               goto clk_dis_all;
+
+       return 0;
+
+clk_dis_all:
+       clk_disable_unprepare(xqspi->refclk);
+clk_dis_pclk:
+       clk_disable_unprepare(xqspi->pclk);
+remove_master:
+       spi_master_put(master);
+
+       return ret;
+}
+
+/**
+ * zynqmp_qspi_remove: Remove method for the QSPI driver
+ * @pdev:      Pointer to the platform_device structure
+ *
+ * This function is called if a device is physically removed from the system or
+ * if the driver module is being unloaded. It frees all resources allocated to
+ * the device.
+ *
+ * Return:     0 Always
+ */
+static int zynqmp_qspi_remove(struct platform_device *pdev)
+{
+       struct spi_master *master = platform_get_drvdata(pdev);
+       struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+
+       zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
+       clk_disable_unprepare(xqspi->refclk);
+       clk_disable_unprepare(xqspi->pclk);
+
+       spi_unregister_master(master);
+
+       return 0;
+}
+
+static const struct of_device_id zynqmp_qspi_of_match[] = {
+       { .compatible = "xlnx,zynqmp-qspi-1.0", },
+       { /* End of table */ }
+};
+
+MODULE_DEVICE_TABLE(of, zynqmp_qspi_of_match);
+
+static struct platform_driver zynqmp_qspi_driver = {
+       .probe = zynqmp_qspi_probe,
+       .remove = zynqmp_qspi_remove,
+       .driver = {
+               .name = "zynqmp-qspi",
+               .of_match_table = zynqmp_qspi_of_match,
+               .pm = &zynqmp_qspi_dev_pm_ops,
+       },
+};
+
+module_platform_driver(zynqmp_qspi_driver);
+
+MODULE_AUTHOR("Xilinx, Inc.");
+MODULE_DESCRIPTION("Xilinx Zynqmp QSPI driver");
+MODULE_LICENSE("GPL");
--
2.1.2

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