Merge tag 'trace-printf-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace...

[drm/drm-misc.git] / drivers / spi / atmel-quadspi.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Driver for Atmel QSPI Controller
 *
 * Copyright (C) 2015 Atmel Corporation
 * Copyright (C) 2018 Cryptera A/S
 *
 * Author: Cyrille Pitchen <cyrille.pitchen@atmel.com>
 * Author: Piotr Bugalski <bugalski.piotr@gmail.com>
 *
 * This driver is based on drivers/mtd/spi-nor/fsl-quadspi.c from Freescale.
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/spi/spi-mem.h>

/* QSPI register offsets */
#define QSPI_CR      0x0000  /* Control Register */
#define QSPI_MR      0x0004  /* Mode Register */
#define QSPI_RD      0x0008  /* Receive Data Register */
#define QSPI_TD      0x000c  /* Transmit Data Register */
#define QSPI_SR      0x0010  /* Status Register */
#define QSPI_IER     0x0014  /* Interrupt Enable Register */
#define QSPI_IDR     0x0018  /* Interrupt Disable Register */
#define QSPI_IMR     0x001c  /* Interrupt Mask Register */
#define QSPI_SCR     0x0020  /* Serial Clock Register */

#define QSPI_IAR     0x0030  /* Instruction Address Register */
#define QSPI_ICR     0x0034  /* Instruction Code Register */
#define QSPI_WICR    0x0034  /* Write Instruction Code Register */
#define QSPI_IFR     0x0038  /* Instruction Frame Register */
#define QSPI_RICR    0x003C  /* Read Instruction Code Register */

#define QSPI_SMR     0x0040  /* Scrambling Mode Register */
#define QSPI_SKR     0x0044  /* Scrambling Key Register */

#define QSPI_WPMR    0x00E4  /* Write Protection Mode Register */
#define QSPI_WPSR    0x00E8  /* Write Protection Status Register */

#define QSPI_VERSION 0x00FC  /* Version Register */


/* Bitfields in QSPI_CR (Control Register) */
#define QSPI_CR_QSPIEN                  BIT(0)
#define QSPI_CR_QSPIDIS                 BIT(1)
#define QSPI_CR_SWRST                   BIT(7)
#define QSPI_CR_LASTXFER                BIT(24)

/* Bitfields in QSPI_MR (Mode Register) */
#define QSPI_MR_SMM                     BIT(0)
#define QSPI_MR_LLB                     BIT(1)
#define QSPI_MR_WDRBT                   BIT(2)
#define QSPI_MR_SMRM                    BIT(3)
#define QSPI_MR_CSMODE_MASK             GENMASK(5, 4)
#define QSPI_MR_CSMODE_NOT_RELOADED     (0 << 4)
#define QSPI_MR_CSMODE_LASTXFER         (1 << 4)
#define QSPI_MR_CSMODE_SYSTEMATICALLY   (2 << 4)
#define QSPI_MR_NBBITS_MASK             GENMASK(11, 8)
#define QSPI_MR_NBBITS(n)               ((((n) - 8) << 8) & QSPI_MR_NBBITS_MASK)
#define QSPI_MR_DLYBCT_MASK             GENMASK(23, 16)
#define QSPI_MR_DLYBCT(n)               (((n) << 16) & QSPI_MR_DLYBCT_MASK)
#define QSPI_MR_DLYCS_MASK              GENMASK(31, 24)
#define QSPI_MR_DLYCS(n)                (((n) << 24) & QSPI_MR_DLYCS_MASK)

/* Bitfields in QSPI_SR/QSPI_IER/QSPI_IDR/QSPI_IMR  */
#define QSPI_SR_RDRF                    BIT(0)
#define QSPI_SR_TDRE                    BIT(1)
#define QSPI_SR_TXEMPTY                 BIT(2)
#define QSPI_SR_OVRES                   BIT(3)
#define QSPI_SR_CSR                     BIT(8)
#define QSPI_SR_CSS                     BIT(9)
#define QSPI_SR_INSTRE                  BIT(10)
#define QSPI_SR_QSPIENS                 BIT(24)

#define QSPI_SR_CMD_COMPLETED   (QSPI_SR_INSTRE | QSPI_SR_CSR)

/* Bitfields in QSPI_SCR (Serial Clock Register) */
#define QSPI_SCR_CPOL                   BIT(0)
#define QSPI_SCR_CPHA                   BIT(1)
#define QSPI_SCR_SCBR_MASK              GENMASK(15, 8)
#define QSPI_SCR_SCBR(n)                (((n) << 8) & QSPI_SCR_SCBR_MASK)
#define QSPI_SCR_DLYBS_MASK             GENMASK(23, 16)
#define QSPI_SCR_DLYBS(n)               (((n) << 16) & QSPI_SCR_DLYBS_MASK)

/* Bitfields in QSPI_ICR (Read/Write Instruction Code Register) */
#define QSPI_ICR_INST_MASK              GENMASK(7, 0)
#define QSPI_ICR_INST(inst)             (((inst) << 0) & QSPI_ICR_INST_MASK)
#define QSPI_ICR_OPT_MASK               GENMASK(23, 16)
#define QSPI_ICR_OPT(opt)               (((opt) << 16) & QSPI_ICR_OPT_MASK)

/* Bitfields in QSPI_IFR (Instruction Frame Register) */
#define QSPI_IFR_WIDTH_MASK             GENMASK(2, 0)
#define QSPI_IFR_WIDTH_SINGLE_BIT_SPI   (0 << 0)
#define QSPI_IFR_WIDTH_DUAL_OUTPUT      (1 << 0)
#define QSPI_IFR_WIDTH_QUAD_OUTPUT      (2 << 0)
#define QSPI_IFR_WIDTH_DUAL_IO          (3 << 0)
#define QSPI_IFR_WIDTH_QUAD_IO          (4 << 0)
#define QSPI_IFR_WIDTH_DUAL_CMD         (5 << 0)
#define QSPI_IFR_WIDTH_QUAD_CMD         (6 << 0)
#define QSPI_IFR_INSTEN                 BIT(4)
#define QSPI_IFR_ADDREN                 BIT(5)
#define QSPI_IFR_OPTEN                  BIT(6)
#define QSPI_IFR_DATAEN                 BIT(7)
#define QSPI_IFR_OPTL_MASK              GENMASK(9, 8)
#define QSPI_IFR_OPTL_1BIT              (0 << 8)
#define QSPI_IFR_OPTL_2BIT              (1 << 8)
#define QSPI_IFR_OPTL_4BIT              (2 << 8)
#define QSPI_IFR_OPTL_8BIT              (3 << 8)
#define QSPI_IFR_ADDRL                  BIT(10)
#define QSPI_IFR_TFRTYP_MEM             BIT(12)
#define QSPI_IFR_SAMA5D2_WRITE_TRSFR    BIT(13)
#define QSPI_IFR_CRM                    BIT(14)
#define QSPI_IFR_NBDUM_MASK             GENMASK(20, 16)
#define QSPI_IFR_NBDUM(n)               (((n) << 16) & QSPI_IFR_NBDUM_MASK)
#define QSPI_IFR_APBTFRTYP_READ         BIT(24) /* Defined in SAM9X60 */

/* Bitfields in QSPI_SMR (Scrambling Mode Register) */
#define QSPI_SMR_SCREN                  BIT(0)
#define QSPI_SMR_RVDIS                  BIT(1)

/* Bitfields in QSPI_WPMR (Write Protection Mode Register) */
#define QSPI_WPMR_WPEN                  BIT(0)
#define QSPI_WPMR_WPKEY_MASK            GENMASK(31, 8)
#define QSPI_WPMR_WPKEY(wpkey)          (((wpkey) << 8) & QSPI_WPMR_WPKEY_MASK)

/* Bitfields in QSPI_WPSR (Write Protection Status Register) */
#define QSPI_WPSR_WPVS                  BIT(0)
#define QSPI_WPSR_WPVSRC_MASK           GENMASK(15, 8)
#define QSPI_WPSR_WPVSRC(src)           (((src) << 8) & QSPI_WPSR_WPVSRC)

struct atmel_qspi_caps {
        bool has_qspick;
        bool has_ricr;
};

struct atmel_qspi {
        void __iomem            *regs;
        void __iomem            *mem;
        struct clk              *pclk;
        struct clk              *qspick;
        struct platform_device  *pdev;
        const struct atmel_qspi_caps *caps;
        resource_size_t         mmap_size;
        u32                     pending;
        u32                     mr;
        u32                     scr;
        struct completion       cmd_completion;
};

struct atmel_qspi_mode {
        u8 cmd_buswidth;
        u8 addr_buswidth;
        u8 data_buswidth;
        u32 config;
};

static const struct atmel_qspi_mode atmel_qspi_modes[] = {
        { 1, 1, 1, QSPI_IFR_WIDTH_SINGLE_BIT_SPI },
        { 1, 1, 2, QSPI_IFR_WIDTH_DUAL_OUTPUT },
        { 1, 1, 4, QSPI_IFR_WIDTH_QUAD_OUTPUT },
        { 1, 2, 2, QSPI_IFR_WIDTH_DUAL_IO },
        { 1, 4, 4, QSPI_IFR_WIDTH_QUAD_IO },
        { 2, 2, 2, QSPI_IFR_WIDTH_DUAL_CMD },
        { 4, 4, 4, QSPI_IFR_WIDTH_QUAD_CMD },
};

#ifdef VERBOSE_DEBUG
static const char *atmel_qspi_reg_name(u32 offset, char *tmp, size_t sz)
{
        switch (offset) {
        case QSPI_CR:
                return "CR";
        case QSPI_MR:
                return "MR";
        case QSPI_RD:
                return "RD";
        case QSPI_TD:
                return "TD";
        case QSPI_SR:
                return "SR";
        case QSPI_IER:
                return "IER";
        case QSPI_IDR:
                return "IDR";
        case QSPI_IMR:
                return "IMR";
        case QSPI_SCR:
                return "SCR";
        case QSPI_IAR:
                return "IAR";
        case QSPI_ICR:
                return "ICR/WICR";
        case QSPI_IFR:
                return "IFR";
        case QSPI_RICR:
                return "RICR";
        case QSPI_SMR:
                return "SMR";
        case QSPI_SKR:
                return "SKR";
        case QSPI_WPMR:
                return "WPMR";
        case QSPI_WPSR:
                return "WPSR";
        case QSPI_VERSION:
                return "VERSION";
        default:
                snprintf(tmp, sz, "0x%02x", offset);
                break;
        }

        return tmp;
}
#endif /* VERBOSE_DEBUG */

static u32 atmel_qspi_read(struct atmel_qspi *aq, u32 offset)
{
        u32 value = readl_relaxed(aq->regs + offset);

#ifdef VERBOSE_DEBUG
        char tmp[8];

        dev_vdbg(&aq->pdev->dev, "read 0x%08x from %s\n", value,
                 atmel_qspi_reg_name(offset, tmp, sizeof(tmp)));
#endif /* VERBOSE_DEBUG */

        return value;
}

static void atmel_qspi_write(u32 value, struct atmel_qspi *aq, u32 offset)
{
#ifdef VERBOSE_DEBUG
        char tmp[8];

        dev_vdbg(&aq->pdev->dev, "write 0x%08x into %s\n", value,
                 atmel_qspi_reg_name(offset, tmp, sizeof(tmp)));
#endif /* VERBOSE_DEBUG */

        writel_relaxed(value, aq->regs + offset);
}

static inline bool atmel_qspi_is_compatible(const struct spi_mem_op *op,
                                            const struct atmel_qspi_mode *mode)
{
        if (op->cmd.buswidth != mode->cmd_buswidth)
                return false;

        if (op->addr.nbytes && op->addr.buswidth != mode->addr_buswidth)
                return false;

        if (op->data.nbytes && op->data.buswidth != mode->data_buswidth)
                return false;

        return true;
}

static int atmel_qspi_find_mode(const struct spi_mem_op *op)
{
        u32 i;

        for (i = 0; i < ARRAY_SIZE(atmel_qspi_modes); i++)
                if (atmel_qspi_is_compatible(op, &atmel_qspi_modes[i]))
                        return i;

        return -EOPNOTSUPP;
}

static bool atmel_qspi_supports_op(struct spi_mem *mem,
                                   const struct spi_mem_op *op)
{
        if (!spi_mem_default_supports_op(mem, op))
                return false;

        if (atmel_qspi_find_mode(op) < 0)
                return false;

        /* special case not supported by hardware */
        if (op->addr.nbytes == 2 && op->cmd.buswidth != op->addr.buswidth &&
            op->dummy.nbytes == 0)
                return false;

        return true;
}

static int atmel_qspi_set_cfg(struct atmel_qspi *aq,
                              const struct spi_mem_op *op, u32 *offset)
{
        u32 iar, icr, ifr;
        u32 dummy_cycles = 0;
        int mode;

        iar = 0;
        icr = QSPI_ICR_INST(op->cmd.opcode);
        ifr = QSPI_IFR_INSTEN;

        mode = atmel_qspi_find_mode(op);
        if (mode < 0)
                return mode;
        ifr |= atmel_qspi_modes[mode].config;

        if (op->dummy.nbytes)
                dummy_cycles = op->dummy.nbytes * 8 / op->dummy.buswidth;

        /*
         * The controller allows 24 and 32-bit addressing while NAND-flash
         * requires 16-bit long. Handling 8-bit long addresses is done using
         * the option field. For the 16-bit addresses, the workaround depends
         * of the number of requested dummy bits. If there are 8 or more dummy
         * cycles, the address is shifted and sent with the first dummy byte.
         * Otherwise opcode is disabled and the first byte of the address
         * contains the command opcode (works only if the opcode and address
         * use the same buswidth). The limitation is when the 16-bit address is
         * used without enough dummy cycles and the opcode is using a different
         * buswidth than the address.
         */
        if (op->addr.buswidth) {
                switch (op->addr.nbytes) {
                case 0:
                        break;
                case 1:
                        ifr |= QSPI_IFR_OPTEN | QSPI_IFR_OPTL_8BIT;
                        icr |= QSPI_ICR_OPT(op->addr.val & 0xff);
                        break;
                case 2:
                        if (dummy_cycles < 8 / op->addr.buswidth) {
                                ifr &= ~QSPI_IFR_INSTEN;
                                ifr |= QSPI_IFR_ADDREN;
                                iar = (op->cmd.opcode << 16) |
                                        (op->addr.val & 0xffff);
                        } else {
                                ifr |= QSPI_IFR_ADDREN;
                                iar = (op->addr.val << 8) & 0xffffff;
                                dummy_cycles -= 8 / op->addr.buswidth;
                        }
                        break;
                case 3:
                        ifr |= QSPI_IFR_ADDREN;
                        iar = op->addr.val & 0xffffff;
                        break;
                case 4:
                        ifr |= QSPI_IFR_ADDREN | QSPI_IFR_ADDRL;
                        iar = op->addr.val & 0x7ffffff;
                        break;
                default:
                        return -ENOTSUPP;
                }
        }

        /* offset of the data access in the QSPI memory space */
        *offset = iar;

        /* Set number of dummy cycles */
        if (dummy_cycles)
                ifr |= QSPI_IFR_NBDUM(dummy_cycles);

        /* Set data enable and data transfer type. */
        if (op->data.nbytes) {
                ifr |= QSPI_IFR_DATAEN;

                if (op->addr.nbytes)
                        ifr |= QSPI_IFR_TFRTYP_MEM;
        }

        /*
         * If the QSPI controller is set in regular SPI mode, set it in
         * Serial Memory Mode (SMM).
         */
        if (!(aq->mr & QSPI_MR_SMM)) {
                aq->mr |= QSPI_MR_SMM;
                atmel_qspi_write(aq->mr, aq, QSPI_MR);
        }

        /* Clear pending interrupts */
        (void)atmel_qspi_read(aq, QSPI_SR);

        /* Set QSPI Instruction Frame registers. */
        if (op->addr.nbytes && !op->data.nbytes)
                atmel_qspi_write(iar, aq, QSPI_IAR);

        if (aq->caps->has_ricr) {
                if (op->data.dir == SPI_MEM_DATA_IN)
                        atmel_qspi_write(icr, aq, QSPI_RICR);
                else
                        atmel_qspi_write(icr, aq, QSPI_WICR);
        } else {
                if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_OUT)
                        ifr |= QSPI_IFR_SAMA5D2_WRITE_TRSFR;

                atmel_qspi_write(icr, aq, QSPI_ICR);
        }

        atmel_qspi_write(ifr, aq, QSPI_IFR);

        return 0;
}

static int atmel_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
{
        struct atmel_qspi *aq = spi_controller_get_devdata(mem->spi->controller);
        u32 sr, offset;
        int err;

        /*
         * Check if the address exceeds the MMIO window size. An improvement
         * would be to add support for regular SPI mode and fall back to it
         * when the flash memories overrun the controller's memory space.
         */
        if (op->addr.val + op->data.nbytes > aq->mmap_size)
                return -ENOTSUPP;

        err = pm_runtime_resume_and_get(&aq->pdev->dev);
        if (err < 0)
                return err;

        err = atmel_qspi_set_cfg(aq, op, &offset);
        if (err)
                goto pm_runtime_put;

        /* Skip to the final steps if there is no data */
        if (op->data.nbytes) {
                /* Dummy read of QSPI_IFR to synchronize APB and AHB accesses */
                (void)atmel_qspi_read(aq, QSPI_IFR);

                /* Send/Receive data */
                if (op->data.dir == SPI_MEM_DATA_IN)
                        memcpy_fromio(op->data.buf.in, aq->mem + offset,
                                      op->data.nbytes);
                else
                        memcpy_toio(aq->mem + offset, op->data.buf.out,
                                    op->data.nbytes);

                /* Release the chip-select */
                atmel_qspi_write(QSPI_CR_LASTXFER, aq, QSPI_CR);
        }

        /* Poll INSTRuction End status */
        sr = atmel_qspi_read(aq, QSPI_SR);
        if ((sr & QSPI_SR_CMD_COMPLETED) == QSPI_SR_CMD_COMPLETED)
                goto pm_runtime_put;

        /* Wait for INSTRuction End interrupt */
        reinit_completion(&aq->cmd_completion);
        aq->pending = sr & QSPI_SR_CMD_COMPLETED;
        atmel_qspi_write(QSPI_SR_CMD_COMPLETED, aq, QSPI_IER);
        if (!wait_for_completion_timeout(&aq->cmd_completion,
                                         msecs_to_jiffies(1000)))
                err = -ETIMEDOUT;
        atmel_qspi_write(QSPI_SR_CMD_COMPLETED, aq, QSPI_IDR);

pm_runtime_put:
        pm_runtime_mark_last_busy(&aq->pdev->dev);
        pm_runtime_put_autosuspend(&aq->pdev->dev);
        return err;
}

static const char *atmel_qspi_get_name(struct spi_mem *spimem)
{
        return dev_name(spimem->spi->dev.parent);
}

static const struct spi_controller_mem_ops atmel_qspi_mem_ops = {
        .supports_op = atmel_qspi_supports_op,
        .exec_op = atmel_qspi_exec_op,
        .get_name = atmel_qspi_get_name
};

static int atmel_qspi_setup(struct spi_device *spi)
{
        struct spi_controller *ctrl = spi->controller;
        struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
        unsigned long src_rate;
        u32 scbr;
        int ret;

        if (ctrl->busy)
                return -EBUSY;

        if (!spi->max_speed_hz)
                return -EINVAL;

        src_rate = clk_get_rate(aq->pclk);
        if (!src_rate)
                return -EINVAL;

        /* Compute the QSPI baudrate */
        scbr = DIV_ROUND_UP(src_rate, spi->max_speed_hz);
        if (scbr > 0)
                scbr--;

        ret = pm_runtime_resume_and_get(ctrl->dev.parent);
        if (ret < 0)
                return ret;

        aq->scr &= ~QSPI_SCR_SCBR_MASK;
        aq->scr |= QSPI_SCR_SCBR(scbr);
        atmel_qspi_write(aq->scr, aq, QSPI_SCR);

        pm_runtime_mark_last_busy(ctrl->dev.parent);
        pm_runtime_put_autosuspend(ctrl->dev.parent);

        return 0;
}

static int atmel_qspi_set_cs_timing(struct spi_device *spi)
{
        struct spi_controller *ctrl = spi->controller;
        struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
        unsigned long clk_rate;
        u32 cs_inactive;
        u32 cs_setup;
        u32 cs_hold;
        int delay;
        int ret;

        clk_rate = clk_get_rate(aq->pclk);
        if (!clk_rate)
                return -EINVAL;

        /* hold */
        delay = spi_delay_to_ns(&spi->cs_hold, NULL);
        if (aq->mr & QSPI_MR_SMM) {
                if (delay > 0)
                        dev_warn(&aq->pdev->dev,
                                 "Ignoring cs_hold, must be 0 in Serial Memory Mode.\n");
                cs_hold = 0;
        } else {
                delay = spi_delay_to_ns(&spi->cs_hold, NULL);
                if (delay < 0)
                        return delay;

                cs_hold = DIV_ROUND_UP((delay * DIV_ROUND_UP(clk_rate, 1000000)), 32000);
        }

        /* setup */
        delay = spi_delay_to_ns(&spi->cs_setup, NULL);
        if (delay < 0)
                return delay;

        cs_setup = DIV_ROUND_UP((delay * DIV_ROUND_UP(clk_rate, 1000000)),
                                1000);

        /* inactive */
        delay = spi_delay_to_ns(&spi->cs_inactive, NULL);
        if (delay < 0)
                return delay;
        cs_inactive = DIV_ROUND_UP((delay * DIV_ROUND_UP(clk_rate, 1000000)), 1000);

        ret = pm_runtime_resume_and_get(ctrl->dev.parent);
        if (ret < 0)
                return ret;

        aq->scr &= ~QSPI_SCR_DLYBS_MASK;
        aq->scr |= QSPI_SCR_DLYBS(cs_setup);
        atmel_qspi_write(aq->scr, aq, QSPI_SCR);

        aq->mr &= ~(QSPI_MR_DLYBCT_MASK | QSPI_MR_DLYCS_MASK);
        aq->mr |= QSPI_MR_DLYBCT(cs_hold) | QSPI_MR_DLYCS(cs_inactive);
        atmel_qspi_write(aq->mr, aq, QSPI_MR);

        pm_runtime_mark_last_busy(ctrl->dev.parent);
        pm_runtime_put_autosuspend(ctrl->dev.parent);

        return 0;
}

static void atmel_qspi_init(struct atmel_qspi *aq)
{
        /* Reset the QSPI controller */
        atmel_qspi_write(QSPI_CR_SWRST, aq, QSPI_CR);

        /* Set the QSPI controller by default in Serial Memory Mode */
        aq->mr |= QSPI_MR_SMM;
        atmel_qspi_write(aq->mr, aq, QSPI_MR);

        /* Enable the QSPI controller */
        atmel_qspi_write(QSPI_CR_QSPIEN, aq, QSPI_CR);
}

static irqreturn_t atmel_qspi_interrupt(int irq, void *dev_id)
{
        struct atmel_qspi *aq = dev_id;
        u32 status, mask, pending;

        status = atmel_qspi_read(aq, QSPI_SR);
        mask = atmel_qspi_read(aq, QSPI_IMR);
        pending = status & mask;

        if (!pending)
                return IRQ_NONE;

        aq->pending |= pending;
        if ((aq->pending & QSPI_SR_CMD_COMPLETED) == QSPI_SR_CMD_COMPLETED)
                complete(&aq->cmd_completion);

        return IRQ_HANDLED;
}

static int atmel_qspi_probe(struct platform_device *pdev)
{
        struct spi_controller *ctrl;
        struct atmel_qspi *aq;
        struct resource *res;
        int irq, err = 0;

        ctrl = devm_spi_alloc_host(&pdev->dev, sizeof(*aq));
        if (!ctrl)
                return -ENOMEM;

        ctrl->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_DUAL | SPI_TX_QUAD;
        ctrl->setup = atmel_qspi_setup;
        ctrl->set_cs_timing = atmel_qspi_set_cs_timing;
        ctrl->bus_num = -1;
        ctrl->mem_ops = &atmel_qspi_mem_ops;
        ctrl->num_chipselect = 1;
        ctrl->dev.of_node = pdev->dev.of_node;
        platform_set_drvdata(pdev, ctrl);

        aq = spi_controller_get_devdata(ctrl);

        init_completion(&aq->cmd_completion);
        aq->pdev = pdev;

        /* Map the registers */
        aq->regs = devm_platform_ioremap_resource_byname(pdev, "qspi_base");
        if (IS_ERR(aq->regs))
                return dev_err_probe(&pdev->dev, PTR_ERR(aq->regs),
                                     "missing registers\n");

        /* Map the AHB memory */
        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_mmap");
        aq->mem = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(aq->mem))
                return dev_err_probe(&pdev->dev, PTR_ERR(aq->mem),
                                     "missing AHB memory\n");

        aq->mmap_size = resource_size(res);

        /* Get the peripheral clock */
        aq->pclk = devm_clk_get(&pdev->dev, "pclk");
        if (IS_ERR(aq->pclk))
                aq->pclk = devm_clk_get(&pdev->dev, NULL);

        if (IS_ERR(aq->pclk))
                return dev_err_probe(&pdev->dev, PTR_ERR(aq->pclk),
                                     "missing peripheral clock\n");

        /* Enable the peripheral clock */
        err = clk_prepare_enable(aq->pclk);
        if (err)
                return dev_err_probe(&pdev->dev, err,
                                     "failed to enable the peripheral clock\n");

        aq->caps = of_device_get_match_data(&pdev->dev);
        if (!aq->caps) {
                dev_err(&pdev->dev, "Could not retrieve QSPI caps\n");
                err = -EINVAL;
                goto disable_pclk;
        }

        if (aq->caps->has_qspick) {
                /* Get the QSPI system clock */
                aq->qspick = devm_clk_get(&pdev->dev, "qspick");
                if (IS_ERR(aq->qspick)) {
                        dev_err(&pdev->dev, "missing system clock\n");
                        err = PTR_ERR(aq->qspick);
                        goto disable_pclk;
                }

                /* Enable the QSPI system clock */
                err = clk_prepare_enable(aq->qspick);
                if (err) {
                        dev_err(&pdev->dev,
                                "failed to enable the QSPI system clock\n");
                        goto disable_pclk;
                }
        }

        /* Request the IRQ */
        irq = platform_get_irq(pdev, 0);
        if (irq < 0) {
                err = irq;
                goto disable_qspick;
        }
        err = devm_request_irq(&pdev->dev, irq, atmel_qspi_interrupt,
                               0, dev_name(&pdev->dev), aq);
        if (err)
                goto disable_qspick;

        pm_runtime_set_autosuspend_delay(&pdev->dev, 500);
        pm_runtime_use_autosuspend(&pdev->dev);
        pm_runtime_set_active(&pdev->dev);
        pm_runtime_enable(&pdev->dev);
        pm_runtime_get_noresume(&pdev->dev);

        atmel_qspi_init(aq);

        err = spi_register_controller(ctrl);
        if (err) {
                pm_runtime_put_noidle(&pdev->dev);
                pm_runtime_disable(&pdev->dev);
                pm_runtime_set_suspended(&pdev->dev);
                pm_runtime_dont_use_autosuspend(&pdev->dev);
                goto disable_qspick;
        }
        pm_runtime_mark_last_busy(&pdev->dev);
        pm_runtime_put_autosuspend(&pdev->dev);

        return 0;

disable_qspick:
        clk_disable_unprepare(aq->qspick);
disable_pclk:
        clk_disable_unprepare(aq->pclk);

        return err;
}

static void atmel_qspi_remove(struct platform_device *pdev)
{
        struct spi_controller *ctrl = platform_get_drvdata(pdev);
        struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
        int ret;

        spi_unregister_controller(ctrl);

        ret = pm_runtime_get_sync(&pdev->dev);
        if (ret >= 0) {
                atmel_qspi_write(QSPI_CR_QSPIDIS, aq, QSPI_CR);
                clk_disable(aq->qspick);
                clk_disable(aq->pclk);
        } else {
                /*
                 * atmel_qspi_runtime_{suspend,resume} just disable and enable
                 * the two clks respectively. So after resume failed these are
                 * off, and we skip hardware access and disabling these clks again.
                 */
                dev_warn(&pdev->dev, "Failed to resume device on remove\n");
        }

        clk_unprepare(aq->qspick);
        clk_unprepare(aq->pclk);

        pm_runtime_disable(&pdev->dev);
        pm_runtime_dont_use_autosuspend(&pdev->dev);
        pm_runtime_put_noidle(&pdev->dev);
}

static int __maybe_unused atmel_qspi_suspend(struct device *dev)
{
        struct spi_controller *ctrl = dev_get_drvdata(dev);
        struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
        int ret;

        ret = pm_runtime_resume_and_get(dev);
        if (ret < 0)
                return ret;

        atmel_qspi_write(QSPI_CR_QSPIDIS, aq, QSPI_CR);

        pm_runtime_mark_last_busy(dev);
        pm_runtime_force_suspend(dev);

        clk_unprepare(aq->qspick);
        clk_unprepare(aq->pclk);

        return 0;
}

static int __maybe_unused atmel_qspi_resume(struct device *dev)
{
        struct spi_controller *ctrl = dev_get_drvdata(dev);
        struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
        int ret;

        ret = clk_prepare(aq->pclk);
        if (ret)
                return ret;

        ret = clk_prepare(aq->qspick);
        if (ret) {
                clk_unprepare(aq->pclk);
                return ret;
        }

        ret = pm_runtime_force_resume(dev);
        if (ret < 0)
                return ret;

        atmel_qspi_init(aq);

        atmel_qspi_write(aq->scr, aq, QSPI_SCR);

        pm_runtime_mark_last_busy(dev);
        pm_runtime_put_autosuspend(dev);

        return 0;
}

static int __maybe_unused atmel_qspi_runtime_suspend(struct device *dev)
{
        struct spi_controller *ctrl = dev_get_drvdata(dev);
        struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);

        clk_disable(aq->qspick);
        clk_disable(aq->pclk);

        return 0;
}

static int __maybe_unused atmel_qspi_runtime_resume(struct device *dev)
{
        struct spi_controller *ctrl = dev_get_drvdata(dev);
        struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
        int ret;

        ret = clk_enable(aq->pclk);
        if (ret)
                return ret;

        ret = clk_enable(aq->qspick);
        if (ret)
                clk_disable(aq->pclk);

        return ret;
}

static const struct dev_pm_ops __maybe_unused atmel_qspi_pm_ops = {
        SET_SYSTEM_SLEEP_PM_OPS(atmel_qspi_suspend, atmel_qspi_resume)
        SET_RUNTIME_PM_OPS(atmel_qspi_runtime_suspend,
                           atmel_qspi_runtime_resume, NULL)
};

static const struct atmel_qspi_caps atmel_sama5d2_qspi_caps = {};

static const struct atmel_qspi_caps atmel_sam9x60_qspi_caps = {
        .has_qspick = true,
        .has_ricr = true,
};

static const struct of_device_id atmel_qspi_dt_ids[] = {
        {
                .compatible = "atmel,sama5d2-qspi",
                .data = &atmel_sama5d2_qspi_caps,
        },
        {
                .compatible = "microchip,sam9x60-qspi",
                .data = &atmel_sam9x60_qspi_caps,
        },
        { /* sentinel */ }
};

MODULE_DEVICE_TABLE(of, atmel_qspi_dt_ids);

static struct platform_driver atmel_qspi_driver = {
        .driver = {
                .name   = "atmel_qspi",
                .of_match_table = atmel_qspi_dt_ids,
                .pm     = pm_ptr(&atmel_qspi_pm_ops),
        },
        .probe          = atmel_qspi_probe,
        .remove         = atmel_qspi_remove,
};
module_platform_driver(atmel_qspi_driver);

MODULE_AUTHOR("Cyrille Pitchen <cyrille.pitchen@atmel.com>");
MODULE_AUTHOR("Piotr Bugalski <bugalski.piotr@gmail.com");
MODULE_DESCRIPTION("Atmel QSPI Controller driver");
MODULE_LICENSE("GPL v2");