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  • /*
     * Copyright 2013-2014 Freescale Semiconductor, Inc.
     *
     * Freescale Quad Serial Peripheral Interface (QSPI) driver
     *
     * SPDX-License-Identifier:	GPL-2.0+
     */
    
    #include <common.h>
    #include <malloc.h>
    #include <spi.h>
    #include <asm/io.h>
    #include <linux/sizes.h>
    #include "fsl_qspi.h"
    
    #define RX_BUFFER_SIZE		0x80
    
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    #ifdef CONFIG_MX6SX
    #define TX_BUFFER_SIZE		0x200
    #else
    
    #define TX_BUFFER_SIZE		0x40
    
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    #endif
    
    
    #define OFFSET_BITS_MASK	0x00ffffff
    
    #define FLASH_STATUS_WEL	0x02
    
    /* SEQID */
    #define SEQID_WREN		1
    #define SEQID_FAST_READ		2
    #define SEQID_RDSR		3
    #define SEQID_SE		4
    #define SEQID_CHIP_ERASE	5
    #define SEQID_PP		6
    #define SEQID_RDID		7
    
    
    /* QSPI CMD */
    #define QSPI_CMD_PP		0x02	/* Page program (up to 256 bytes) */
    #define QSPI_CMD_RDSR		0x05	/* Read status register */
    #define QSPI_CMD_WREN		0x06	/* Write enable */
    #define QSPI_CMD_FAST_READ	0x0b	/* Read data bytes (high frequency) */
    #define QSPI_CMD_CHIP_ERASE	0xc7	/* Erase whole flash chip */
    #define QSPI_CMD_SE		0xd8	/* Sector erase (usually 64KiB) */
    #define QSPI_CMD_RDID		0x9f	/* Read JEDEC ID */
    
    /* 4-byte address QSPI CMD - used on Spansion and some Macronix flashes */
    #define QSPI_CMD_FAST_READ_4B	0x0c    /* Read data bytes (high frequency) */
    #define QSPI_CMD_PP_4B		0x12    /* Page program (up to 256 bytes) */
    #define QSPI_CMD_SE_4B		0xdc    /* Sector erase (usually 64KiB) */
    
    
    #ifdef CONFIG_SYS_FSL_QSPI_LE
    #define qspi_read32		in_le32
    #define qspi_write32		out_le32
    #elif defined(CONFIG_SYS_FSL_QSPI_BE)
    #define qspi_read32		in_be32
    #define qspi_write32		out_be32
    #endif
    
    static unsigned long spi_bases[] = {
    	QSPI0_BASE_ADDR,
    
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    #ifdef CONFIG_MX6SX
    	QSPI1_BASE_ADDR,
    #endif
    
    };
    
    static unsigned long amba_bases[] = {
    	QSPI0_AMBA_BASE,
    
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    #ifdef CONFIG_MX6SX
    	QSPI1_AMBA_BASE,
    #endif
    
    };
    
    struct fsl_qspi {
    	struct spi_slave slave;
    	unsigned long reg_base;
    	unsigned long amba_base;
    	u32 sf_addr;
    	u8 cur_seqid;
    };
    
    /* QSPI support swapping the flash read/write data
     * in hardware for LS102xA, but not for VF610 */
    static inline u32 qspi_endian_xchg(u32 data)
    {
    #ifdef CONFIG_VF610
    	return swab32(data);
    #else
    	return data;
    #endif
    }
    
    static inline struct fsl_qspi *to_qspi_spi(struct spi_slave *slave)
    {
    	return container_of(slave, struct fsl_qspi, slave);
    }
    
    static void qspi_set_lut(struct fsl_qspi *qspi)
    {
    	struct fsl_qspi_regs *regs = (struct fsl_qspi_regs *)qspi->reg_base;
    	u32 lut_base;
    
    	/* Unlock the LUT */
    	qspi_write32(&regs->lutkey, LUT_KEY_VALUE);
    	qspi_write32(&regs->lckcr, QSPI_LCKCR_UNLOCK);
    
    	/* Write Enable */
    	lut_base = SEQID_WREN * 4;
    
    	qspi_write32(&regs->lut[lut_base], OPRND0(QSPI_CMD_WREN) |
    
    		PAD0(LUT_PAD1) | INSTR0(LUT_CMD));
    	qspi_write32(&regs->lut[lut_base + 1], 0);
    	qspi_write32(&regs->lut[lut_base + 2], 0);
    	qspi_write32(&regs->lut[lut_base + 3], 0);
    
    	/* Fast Read */
    	lut_base = SEQID_FAST_READ * 4;
    	if (FSL_QSPI_FLASH_SIZE  <= SZ_16M)
    
    		qspi_write32(&regs->lut[lut_base], OPRND0(QSPI_CMD_FAST_READ) |
    
    			PAD0(LUT_PAD1) | INSTR0(LUT_CMD) | OPRND1(ADDR24BIT) |
    			PAD1(LUT_PAD1) | INSTR1(LUT_ADDR));
    	else
    
    		qspi_write32(&regs->lut[lut_base],
    			     OPRND0(QSPI_CMD_FAST_READ_4B) |
    			     PAD0(LUT_PAD1) | INSTR0(LUT_CMD) |
    			     OPRND1(ADDR32BIT) | PAD1(LUT_PAD1) |
    			     INSTR1(LUT_ADDR));
    
    	qspi_write32(&regs->lut[lut_base + 1], OPRND0(8) | PAD0(LUT_PAD1) |
    		INSTR0(LUT_DUMMY) | OPRND1(RX_BUFFER_SIZE) | PAD1(LUT_PAD1) |
    		INSTR1(LUT_READ));
    	qspi_write32(&regs->lut[lut_base + 2], 0);
    	qspi_write32(&regs->lut[lut_base + 3], 0);
    
    	/* Read Status */
    	lut_base = SEQID_RDSR * 4;
    
    	qspi_write32(&regs->lut[lut_base], OPRND0(QSPI_CMD_RDSR) |
    
    		PAD0(LUT_PAD1) | INSTR0(LUT_CMD) | OPRND1(1) |
    		PAD1(LUT_PAD1) | INSTR1(LUT_READ));
    	qspi_write32(&regs->lut[lut_base + 1], 0);
    	qspi_write32(&regs->lut[lut_base + 2], 0);
    	qspi_write32(&regs->lut[lut_base + 3], 0);
    
    	/* Erase a sector */
    	lut_base = SEQID_SE * 4;
    	if (FSL_QSPI_FLASH_SIZE  <= SZ_16M)
    
    		qspi_write32(&regs->lut[lut_base], OPRND0(QSPI_CMD_SE) |
    
    			PAD0(LUT_PAD1) | INSTR0(LUT_CMD) | OPRND1(ADDR24BIT) |
    			PAD1(LUT_PAD1) | INSTR1(LUT_ADDR));
    	else
    
    		qspi_write32(&regs->lut[lut_base], OPRND0(QSPI_CMD_SE_4B) |
    
    			PAD0(LUT_PAD1) | INSTR0(LUT_CMD) | OPRND1(ADDR32BIT) |
    			PAD1(LUT_PAD1) | INSTR1(LUT_ADDR));
    	qspi_write32(&regs->lut[lut_base + 1], 0);
    	qspi_write32(&regs->lut[lut_base + 2], 0);
    	qspi_write32(&regs->lut[lut_base + 3], 0);
    
    	/* Erase the whole chip */
    	lut_base = SEQID_CHIP_ERASE * 4;
    
    	qspi_write32(&regs->lut[lut_base], OPRND0(QSPI_CMD_CHIP_ERASE) |
    
    		PAD0(LUT_PAD1) | INSTR0(LUT_CMD));
    	qspi_write32(&regs->lut[lut_base + 1], 0);
    	qspi_write32(&regs->lut[lut_base + 2], 0);
    	qspi_write32(&regs->lut[lut_base + 3], 0);
    
    	/* Page Program */
    	lut_base = SEQID_PP * 4;
    	if (FSL_QSPI_FLASH_SIZE  <= SZ_16M)
    
    		qspi_write32(&regs->lut[lut_base], OPRND0(QSPI_CMD_PP) |
    
    			PAD0(LUT_PAD1) | INSTR0(LUT_CMD) | OPRND1(ADDR24BIT) |
    			PAD1(LUT_PAD1) | INSTR1(LUT_ADDR));
    	else
    
    		qspi_write32(&regs->lut[lut_base], OPRND0(QSPI_CMD_PP_4B) |
    
    			PAD0(LUT_PAD1) | INSTR0(LUT_CMD) | OPRND1(ADDR32BIT) |
    			PAD1(LUT_PAD1) | INSTR1(LUT_ADDR));
    
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    #ifdef CONFIG_MX6SX
    	/*
    	 * To MX6SX, OPRND0(TX_BUFFER_SIZE) can not work correctly.
    	 * So, Use IDATSZ in IPCR to determine the size and here set 0.
    	 */
    	qspi_write32(&regs->lut[lut_base + 1], OPRND0(0) |
    		     PAD0(LUT_PAD1) | INSTR0(LUT_WRITE));
    #else
    
    	qspi_write32(&regs->lut[lut_base + 1], OPRND0(TX_BUFFER_SIZE) |
    		PAD0(LUT_PAD1) | INSTR0(LUT_WRITE));
    
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    #endif
    
    	qspi_write32(&regs->lut[lut_base + 2], 0);
    	qspi_write32(&regs->lut[lut_base + 3], 0);
    
    	/* READ ID */
    	lut_base = SEQID_RDID * 4;
    
    	qspi_write32(&regs->lut[lut_base], OPRND0(QSPI_CMD_RDID) |
    
    		PAD0(LUT_PAD1) | INSTR0(LUT_CMD) | OPRND1(8) |
    		PAD1(LUT_PAD1) | INSTR1(LUT_READ));
    	qspi_write32(&regs->lut[lut_base + 1], 0);
    	qspi_write32(&regs->lut[lut_base + 2], 0);
    	qspi_write32(&regs->lut[lut_base + 3], 0);
    
    	/* Lock the LUT */
    	qspi_write32(&regs->lutkey, LUT_KEY_VALUE);
    	qspi_write32(&regs->lckcr, QSPI_LCKCR_LOCK);
    }
    
    void spi_init()
    {
    	/* do nothing */
    }
    
    struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
    		unsigned int max_hz, unsigned int mode)
    {
    	struct fsl_qspi *qspi;
    	struct fsl_qspi_regs *regs;
    	u32 reg_val, smpr_val;
    	u32 total_size, seq_id;
    
    	if (bus >= ARRAY_SIZE(spi_bases))
    		return NULL;
    
    
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    	if (cs >= FSL_QSPI_FLASH_NUM)
    		return NULL;
    
    
    	qspi = spi_alloc_slave(struct fsl_qspi, bus, cs);
    	if (!qspi)
    		return NULL;
    
    	qspi->reg_base = spi_bases[bus];
    
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    	/*
    	 * According cs, use different amba_base to choose the
    	 * corresponding flash devices.
    	 *
    	 * If not, only one flash device is used even if passing
    	 * different cs using `sf probe`
    	 */
    	qspi->amba_base = amba_bases[bus] + cs * FSL_QSPI_FLASH_SIZE;
    
    
    	qspi->slave.max_write_size = TX_BUFFER_SIZE;
    
    	regs = (struct fsl_qspi_regs *)qspi->reg_base;
    	qspi_write32(&regs->mcr, QSPI_MCR_RESERVED_MASK | QSPI_MCR_MDIS_MASK);
    
    	smpr_val = qspi_read32(&regs->smpr);
    	qspi_write32(&regs->smpr, smpr_val & ~(QSPI_SMPR_FSDLY_MASK |
    		QSPI_SMPR_FSPHS_MASK | QSPI_SMPR_HSENA_MASK));
    	qspi_write32(&regs->mcr, QSPI_MCR_RESERVED_MASK);
    
    	total_size = FSL_QSPI_FLASH_SIZE * FSL_QSPI_FLASH_NUM;
    
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    	/*
    	 * Any read access to non-implemented addresses will provide
    	 * undefined results.
    	 *
    	 * In case single die flash devices, TOP_ADDR_MEMA2 and
    	 * TOP_ADDR_MEMB2 should be initialized/programmed to
    	 * TOP_ADDR_MEMA1 and TOP_ADDR_MEMB1 respectively - in effect,
    	 * setting the size of these devices to 0.  This would ensure
    	 * that the complete memory map is assigned to only one flash device.
    	 */
    	qspi_write32(&regs->sfa1ad, FSL_QSPI_FLASH_SIZE | amba_bases[bus]);
    	qspi_write32(&regs->sfa2ad, FSL_QSPI_FLASH_SIZE | amba_bases[bus]);
    	qspi_write32(&regs->sfb1ad, total_size | amba_bases[bus]);
    	qspi_write32(&regs->sfb2ad, total_size | amba_bases[bus]);
    
    
    	qspi_set_lut(qspi);
    
    	smpr_val = qspi_read32(&regs->smpr);
    	smpr_val &= ~QSPI_SMPR_DDRSMP_MASK;
    	qspi_write32(&regs->smpr, smpr_val);
    	qspi_write32(&regs->mcr, QSPI_MCR_RESERVED_MASK);
    
    	seq_id = 0;
    	reg_val = qspi_read32(&regs->bfgencr);
    	reg_val &= ~QSPI_BFGENCR_SEQID_MASK;
    	reg_val |= (seq_id << QSPI_BFGENCR_SEQID_SHIFT);
    	reg_val &= ~QSPI_BFGENCR_PAR_EN_MASK;
    	qspi_write32(&regs->bfgencr, reg_val);
    
    	return &qspi->slave;
    }
    
    void spi_free_slave(struct spi_slave *slave)
    {
    	struct fsl_qspi *qspi = to_qspi_spi(slave);
    
    	free(qspi);
    }
    
    int spi_claim_bus(struct spi_slave *slave)
    {
    	return 0;
    }
    
    static void qspi_op_rdid(struct fsl_qspi *qspi, u32 *rxbuf, u32 len)
    {
    	struct fsl_qspi_regs *regs = (struct fsl_qspi_regs *)qspi->reg_base;
    	u32 mcr_reg, rbsr_reg, data;
    	int i, size;
    
    	mcr_reg = qspi_read32(&regs->mcr);
    	qspi_write32(&regs->mcr, QSPI_MCR_CLR_RXF_MASK | QSPI_MCR_CLR_TXF_MASK |
    		QSPI_MCR_RESERVED_MASK | QSPI_MCR_END_CFD_LE);
    	qspi_write32(&regs->rbct, QSPI_RBCT_RXBRD_USEIPS);
    
    	qspi_write32(&regs->sfar, qspi->amba_base);
    
    	qspi_write32(&regs->ipcr, (SEQID_RDID << QSPI_IPCR_SEQID_SHIFT) | 0);
    	while (qspi_read32(&regs->sr) & QSPI_SR_BUSY_MASK)
    		;
    
    	i = 0;
    	size = len;
    	while ((RX_BUFFER_SIZE >= size) && (size > 0)) {
    		rbsr_reg = qspi_read32(&regs->rbsr);
    		if (rbsr_reg & QSPI_RBSR_RDBFL_MASK) {
    			data = qspi_read32(&regs->rbdr[i]);
    			data = qspi_endian_xchg(data);
    			memcpy(rxbuf, &data, 4);
    			rxbuf++;
    			size -= 4;
    			i++;
    		}
    	}
    
    	qspi_write32(&regs->mcr, mcr_reg);
    }
    
    static void qspi_op_read(struct fsl_qspi *qspi, u32 *rxbuf, u32 len)
    {
    	struct fsl_qspi_regs *regs = (struct fsl_qspi_regs *)qspi->reg_base;
    	u32 mcr_reg, data;
    	int i, size;
    	u32 to_or_from;
    
    	mcr_reg = qspi_read32(&regs->mcr);
    	qspi_write32(&regs->mcr, QSPI_MCR_CLR_RXF_MASK | QSPI_MCR_CLR_TXF_MASK |
    		QSPI_MCR_RESERVED_MASK | QSPI_MCR_END_CFD_LE);
    	qspi_write32(&regs->rbct, QSPI_RBCT_RXBRD_USEIPS);
    
    	to_or_from = qspi->sf_addr + qspi->amba_base;
    
    	while (len > 0) {
    		qspi_write32(&regs->sfar, to_or_from);
    
    		size = (len > RX_BUFFER_SIZE) ?
    			RX_BUFFER_SIZE : len;
    
    		qspi_write32(&regs->ipcr,
    			(SEQID_FAST_READ << QSPI_IPCR_SEQID_SHIFT) | size);
    		while (qspi_read32(&regs->sr) & QSPI_SR_BUSY_MASK)
    			;
    
    		to_or_from += size;
    		len -= size;
    
    		i = 0;
    		while ((RX_BUFFER_SIZE >= size) && (size > 0)) {
    			data = qspi_read32(&regs->rbdr[i]);
    			data = qspi_endian_xchg(data);
    			memcpy(rxbuf, &data, 4);
    			rxbuf++;
    			size -= 4;
    			i++;
    		}
    		qspi_write32(&regs->mcr, qspi_read32(&regs->mcr) |
    			QSPI_MCR_CLR_RXF_MASK);
    	}
    
    	qspi_write32(&regs->mcr, mcr_reg);
    }
    
    static void qspi_op_pp(struct fsl_qspi *qspi, u32 *txbuf, u32 len)
    {
    	struct fsl_qspi_regs *regs = (struct fsl_qspi_regs *)qspi->reg_base;
    	u32 mcr_reg, data, reg, status_reg;
    	int i, size, tx_size;
    	u32 to_or_from = 0;
    
    	mcr_reg = qspi_read32(&regs->mcr);
    	qspi_write32(&regs->mcr, QSPI_MCR_CLR_RXF_MASK | QSPI_MCR_CLR_TXF_MASK |
    		QSPI_MCR_RESERVED_MASK | QSPI_MCR_END_CFD_LE);
    	qspi_write32(&regs->rbct, QSPI_RBCT_RXBRD_USEIPS);
    
    	status_reg = 0;
    	while ((status_reg & FLASH_STATUS_WEL) != FLASH_STATUS_WEL) {
    		qspi_write32(&regs->ipcr,
    			(SEQID_WREN << QSPI_IPCR_SEQID_SHIFT) | 0);
    		while (qspi_read32(&regs->sr) & QSPI_SR_BUSY_MASK)
    			;
    
    		qspi_write32(&regs->ipcr,
    			(SEQID_RDSR << QSPI_IPCR_SEQID_SHIFT) | 1);
    		while (qspi_read32(&regs->sr) & QSPI_SR_BUSY_MASK)
    			;
    
    		reg = qspi_read32(&regs->rbsr);
    		if (reg & QSPI_RBSR_RDBFL_MASK) {
    			status_reg = qspi_read32(&regs->rbdr[0]);
    			status_reg = qspi_endian_xchg(status_reg);
    		}
    		qspi_write32(&regs->mcr,
    			qspi_read32(&regs->mcr) | QSPI_MCR_CLR_RXF_MASK);
    	}
    
    	to_or_from = qspi->sf_addr + qspi->amba_base;
    	qspi_write32(&regs->sfar, to_or_from);
    
    	tx_size = (len > TX_BUFFER_SIZE) ?
    		TX_BUFFER_SIZE : len;
    
    	size = (tx_size + 3) / 4;
    
    	for (i = 0; i < size; i++) {
    		data = qspi_endian_xchg(*txbuf);
    		qspi_write32(&regs->tbdr, data);
    		txbuf++;
    	}
    
    	qspi_write32(&regs->ipcr,
    		(SEQID_PP << QSPI_IPCR_SEQID_SHIFT) | tx_size);
    	while (qspi_read32(&regs->sr) & QSPI_SR_BUSY_MASK)
    		;
    
    	qspi_write32(&regs->mcr, mcr_reg);
    }
    
    static void qspi_op_rdsr(struct fsl_qspi *qspi, u32 *rxbuf)
    {
    	struct fsl_qspi_regs *regs = (struct fsl_qspi_regs *)qspi->reg_base;
    	u32 mcr_reg, reg, data;
    
    	mcr_reg = qspi_read32(&regs->mcr);
    	qspi_write32(&regs->mcr, QSPI_MCR_CLR_RXF_MASK | QSPI_MCR_CLR_TXF_MASK |
    		QSPI_MCR_RESERVED_MASK | QSPI_MCR_END_CFD_LE);
    	qspi_write32(&regs->rbct, QSPI_RBCT_RXBRD_USEIPS);
    
    	qspi_write32(&regs->sfar, qspi->amba_base);
    
    	qspi_write32(&regs->ipcr,
    		(SEQID_RDSR << QSPI_IPCR_SEQID_SHIFT) | 0);
    	while (qspi_read32(&regs->sr) & QSPI_SR_BUSY_MASK)
    		;
    
    	while (1) {
    		reg = qspi_read32(&regs->rbsr);
    		if (reg & QSPI_RBSR_RDBFL_MASK) {
    			data = qspi_read32(&regs->rbdr[0]);
    			data = qspi_endian_xchg(data);
    			memcpy(rxbuf, &data, 4);
    			qspi_write32(&regs->mcr, qspi_read32(&regs->mcr) |
    				QSPI_MCR_CLR_RXF_MASK);
    			break;
    		}
    	}
    
    	qspi_write32(&regs->mcr, mcr_reg);
    }
    
    static void qspi_op_se(struct fsl_qspi *qspi)
    {
    	struct fsl_qspi_regs *regs = (struct fsl_qspi_regs *)qspi->reg_base;
    	u32 mcr_reg;
    	u32 to_or_from = 0;
    
    	mcr_reg = qspi_read32(&regs->mcr);
    	qspi_write32(&regs->mcr, QSPI_MCR_CLR_RXF_MASK | QSPI_MCR_CLR_TXF_MASK |
    		QSPI_MCR_RESERVED_MASK | QSPI_MCR_END_CFD_LE);
    	qspi_write32(&regs->rbct, QSPI_RBCT_RXBRD_USEIPS);
    
    	to_or_from = qspi->sf_addr + qspi->amba_base;
    	qspi_write32(&regs->sfar, to_or_from);
    
    	qspi_write32(&regs->ipcr,
    		(SEQID_WREN << QSPI_IPCR_SEQID_SHIFT) | 0);
    	while (qspi_read32(&regs->sr) & QSPI_SR_BUSY_MASK)
    		;
    
    	qspi_write32(&regs->ipcr,
    		(SEQID_SE << QSPI_IPCR_SEQID_SHIFT) | 0);
    	while (qspi_read32(&regs->sr) & QSPI_SR_BUSY_MASK)
    		;
    
    	qspi_write32(&regs->mcr, mcr_reg);
    }
    
    int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
    		const void *dout, void *din, unsigned long flags)
    {
    	struct fsl_qspi *qspi = to_qspi_spi(slave);
    	u32 bytes = DIV_ROUND_UP(bitlen, 8);
    	static u32 pp_sfaddr;
    	u32 txbuf;
    
    	if (dout) {
    		memcpy(&txbuf, dout, 4);
    		qspi->cur_seqid = *(u8 *)dout;
    
    		if (flags == SPI_XFER_END) {
    			qspi->sf_addr = pp_sfaddr;
    			qspi_op_pp(qspi, (u32 *)dout, bytes);
    			return 0;
    		}
    
    
    		if (qspi->cur_seqid == QSPI_CMD_FAST_READ) {
    
    			qspi->sf_addr = swab32(txbuf) & OFFSET_BITS_MASK;
    
    		} else if (qspi->cur_seqid == QSPI_CMD_SE) {
    
    			qspi->sf_addr = swab32(txbuf) & OFFSET_BITS_MASK;
    			qspi_op_se(qspi);
    
    		} else if (qspi->cur_seqid == QSPI_CMD_PP) {
    
    			pp_sfaddr = swab32(txbuf) & OFFSET_BITS_MASK;
    		}
    	}
    
    	if (din) {
    
    		if (qspi->cur_seqid == QSPI_CMD_FAST_READ)
    
    			qspi_op_read(qspi, din, bytes);
    
    		else if (qspi->cur_seqid == QSPI_CMD_RDID)
    
    			qspi_op_rdid(qspi, din, bytes);
    
    		else if (qspi->cur_seqid == QSPI_CMD_RDSR)
    
    			qspi_op_rdsr(qspi, din);
    	}
    
    	return 0;
    }
    
    void spi_release_bus(struct spi_slave *slave)
    {
    	/* Nothing to do */
    }