mtd: spi-nor: introduce SPI 1-2-2 and SPI 1-4-4 protocols

This patch changes the prototype of spi_nor_scan(): its 3rd parameter
is replaced by a 'struct spi_nor_hwcaps' pointer, which tells the spi-nor
framework about the actual hardware capabilities supported by the SPI
controller and its driver.

Besides, this patch also introduces a new 'struct spi_nor_flash_parameter'
telling the spi-nor framework about the hardware capabilities supported by
the SPI flash memory and the associated settings required to use those
hardware caps.

Then, to improve the readability of spi_nor_scan(), the discovery of the
memory settings and the memory initialization are now split into two
dedicated functions.

1 - spi_nor_init_params()

The spi_nor_init_params() function is responsible for initializing the
'struct spi_nor_flash_parameter'. Currently this structure is filled with
legacy values but further patches will allow to override some parameter
values dynamically, for instance by reading the JESD216 Serial Flash
Discoverable Parameter (SFDP) tables from the SPI memory.
The spi_nor_init_params() function only deals with the hardware
capabilities of the SPI flash memory: especially it doesn't care about
the hardware capabilities supported by the SPI controller.

2 - spi_nor_setup()

The second function is called once the 'struct spi_nor_flash_parameter'
has been initialized by spi_nor_init_params().
With both 'struct spi_nor_flash_parameter' and 'struct spi_nor_hwcaps',
the new argument of spi_nor_scan(), spi_nor_setup() computes the best
match between hardware caps supported by both the (Q)SPI memory and
controller hence selecting the relevant settings for (Fast) Read and Page
Program operations.
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>

drivers/mtd/devices/m25p80.c

@@ -111,14 +111,7 @@ static ssize_t m25p80_write(struct spi_nor *nor, loff_t to, size_t len,
 
 static inline unsigned int m25p80_rx_nbits(struct spi_nor *nor)
 {
-	switch (nor->flash_read) {
-	case SPI_NOR_DUAL:
-		return 2;
-	case SPI_NOR_QUAD:
-		return 4;
-	default:
-		return 0;
-	}
+	return spi_nor_get_protocol_data_nbits(nor->read_proto);
 }
 
 /*
@@ -196,7 +189,11 @@ static int m25p_probe(struct spi_device *spi)
 	struct flash_platform_data	*data;
 	struct m25p *flash;
 	struct spi_nor *nor;
-	enum read_mode mode = SPI_NOR_NORMAL;
+	struct spi_nor_hwcaps hwcaps = {
+		.mask = SNOR_HWCAPS_READ |
+			SNOR_HWCAPS_READ_FAST |
+			SNOR_HWCAPS_PP,
+	};
 	char *flash_name;
 	int ret;
 
@@ -222,9 +219,9 @@ static int m25p_probe(struct spi_device *spi)
 	flash->spi = spi;
 
 	if (spi->mode & SPI_RX_QUAD)
-		mode = SPI_NOR_QUAD;
+		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
 	else if (spi->mode & SPI_RX_DUAL)
-		mode = SPI_NOR_DUAL;
+		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
 
 	if (data && data->name)
 		nor->mtd.name = data->name;
@@ -241,7 +238,7 @@ static int m25p_probe(struct spi_device *spi)
 	else
 		flash_name = spi->modalias;
 
-	ret = spi_nor_scan(nor, flash_name, mode);
+	ret = spi_nor_scan(nor, flash_name, &hwcaps);
 	if (ret)
 		return ret;
 

drivers/mtd/spi-nor/aspeed-smc.c

@@ -585,14 +585,12 @@ static int aspeed_smc_chip_setup_finish(struct aspeed_smc_chip *chip)
 	 * TODO: Adjust clocks if fast read is supported and interpret
 	 * SPI-NOR flags to adjust controller settings.
 	 */
-	switch (chip->nor.flash_read) {
-	case SPI_NOR_NORMAL:
-		cmd = CONTROL_COMMAND_MODE_NORMAL;
-		break;
-	case SPI_NOR_FAST:
-		cmd = CONTROL_COMMAND_MODE_FREAD;
-		break;
-	default:
+	if (chip->nor.read_proto == SNOR_PROTO_1_1_1) {
+		if (chip->nor.read_dummy == 0)
+			cmd = CONTROL_COMMAND_MODE_NORMAL;
+		else
+			cmd = CONTROL_COMMAND_MODE_FREAD;
+	} else {
 		dev_err(chip->nor.dev, "unsupported SPI read mode\n");
 		return -EINVAL;
 	}
@@ -608,6 +606,11 @@ static int aspeed_smc_chip_setup_finish(struct aspeed_smc_chip *chip)
 static int aspeed_smc_setup_flash(struct aspeed_smc_controller *controller,
 				  struct device_node *np, struct resource *r)
 {
+	const struct spi_nor_hwcaps hwcaps = {
+		.mask = SNOR_HWCAPS_READ |
+			SNOR_HWCAPS_READ_FAST |
+			SNOR_HWCAPS_PP,
+	};
 	const struct aspeed_smc_info *info = controller->info;
 	struct device *dev = controller->dev;
 	struct device_node *child;
@@ -671,11 +674,11 @@ static int aspeed_smc_setup_flash(struct aspeed_smc_controller *controller,
 			break;
 
 		/*
-		 * TODO: Add support for SPI_NOR_QUAD and SPI_NOR_DUAL
+		 * TODO: Add support for Dual and Quad SPI protocols
 		 * attach when board support is present as determined
 		 * by of property.
 		 */
-		ret = spi_nor_scan(nor, NULL, SPI_NOR_NORMAL);
+		ret = spi_nor_scan(nor, NULL, &hwcaps);
 		if (ret)
 			break;
 

drivers/mtd/spi-nor/atmel-quadspi.c

@@ -275,14 +275,48 @@ static void atmel_qspi_debug_command(struct atmel_qspi *aq,
 
 static int atmel_qspi_run_command(struct atmel_qspi *aq,
 				  const struct atmel_qspi_command *cmd,
-				  u32 ifr_tfrtyp, u32 ifr_width)
+				  u32 ifr_tfrtyp, enum spi_nor_protocol proto)
 {
 	u32 iar, icr, ifr, sr;
 	int err = 0;
 
 	iar = 0;
 	icr = 0;
-	ifr = ifr_tfrtyp | ifr_width;
+	ifr = ifr_tfrtyp;
+
+	/* Set the SPI protocol */
+	switch (proto) {
+	case SNOR_PROTO_1_1_1:
+		ifr |= QSPI_IFR_WIDTH_SINGLE_BIT_SPI;
+		break;
+
+	case SNOR_PROTO_1_1_2:
+		ifr |= QSPI_IFR_WIDTH_DUAL_OUTPUT;
+		break;
+
+	case SNOR_PROTO_1_1_4:
+		ifr |= QSPI_IFR_WIDTH_QUAD_OUTPUT;
+		break;
+
+	case SNOR_PROTO_1_2_2:
+		ifr |= QSPI_IFR_WIDTH_DUAL_IO;
+		break;
+
+	case SNOR_PROTO_1_4_4:
+		ifr |= QSPI_IFR_WIDTH_QUAD_IO;
+		break;
+
+	case SNOR_PROTO_2_2_2:
+		ifr |= QSPI_IFR_WIDTH_DUAL_CMD;
+		break;
+
+	case SNOR_PROTO_4_4_4:
+		ifr |= QSPI_IFR_WIDTH_QUAD_CMD;
+		break;
+
+	default:
+		return -EINVAL;
+	}
 
 	/* Compute instruction parameters */
 	if (cmd->enable.bits.instruction) {
@@ -434,7 +468,7 @@ static int atmel_qspi_read_reg(struct spi_nor *nor, u8 opcode,
 	cmd.rx_buf = buf;
 	cmd.buf_len = len;
 	return atmel_qspi_run_command(aq, &cmd, QSPI_IFR_TFRTYP_TRSFR_READ,
-				      QSPI_IFR_WIDTH_SINGLE_BIT_SPI);
+				      nor->reg_proto);
 }
 
 static int atmel_qspi_write_reg(struct spi_nor *nor, u8 opcode,
@@ -450,7 +484,7 @@ static int atmel_qspi_write_reg(struct spi_nor *nor, u8 opcode,
 	cmd.tx_buf = buf;
 	cmd.buf_len = len;
 	return atmel_qspi_run_command(aq, &cmd, QSPI_IFR_TFRTYP_TRSFR_WRITE,
-				      QSPI_IFR_WIDTH_SINGLE_BIT_SPI);
+				      nor->reg_proto);
 }
 
 static ssize_t atmel_qspi_write(struct spi_nor *nor, loff_t to, size_t len,
@@ -469,7 +503,7 @@ static ssize_t atmel_qspi_write(struct spi_nor *nor, loff_t to, size_t len,
 	cmd.tx_buf = write_buf;
 	cmd.buf_len = len;
 	ret = atmel_qspi_run_command(aq, &cmd, QSPI_IFR_TFRTYP_TRSFR_WRITE_MEM,
-				     QSPI_IFR_WIDTH_SINGLE_BIT_SPI);
+				     nor->write_proto);
 	return (ret < 0) ? ret : len;
 }
 
@@ -484,7 +518,7 @@ static int atmel_qspi_erase(struct spi_nor *nor, loff_t offs)
 	cmd.instruction = nor->erase_opcode;
 	cmd.address = (u32)offs;
 	return atmel_qspi_run_command(aq, &cmd, QSPI_IFR_TFRTYP_TRSFR_WRITE,
-				      QSPI_IFR_WIDTH_SINGLE_BIT_SPI);
+				      nor->reg_proto);
 }
 
 static ssize_t atmel_qspi_read(struct spi_nor *nor, loff_t from, size_t len,
@@ -493,27 +527,8 @@ static ssize_t atmel_qspi_read(struct spi_nor *nor, loff_t from, size_t len,
 	struct atmel_qspi *aq = nor->priv;
 	struct atmel_qspi_command cmd;
 	u8 num_mode_cycles, num_dummy_cycles;
-	u32 ifr_width;
 	ssize_t ret;
 
-	switch (nor->flash_read) {
-	case SPI_NOR_NORMAL:
-	case SPI_NOR_FAST:
-		ifr_width = QSPI_IFR_WIDTH_SINGLE_BIT_SPI;
-		break;
-
-	case SPI_NOR_DUAL:
-		ifr_width = QSPI_IFR_WIDTH_DUAL_OUTPUT;
-		break;
-
-	case SPI_NOR_QUAD:
-		ifr_width = QSPI_IFR_WIDTH_QUAD_OUTPUT;
-		break;
-
-	default:
-		return -EINVAL;
-	}
-
 	if (nor->read_dummy >= 2) {
 		num_mode_cycles = 2;
 		num_dummy_cycles = nor->read_dummy - 2;
@@ -536,7 +551,7 @@ static ssize_t atmel_qspi_read(struct spi_nor *nor, loff_t from, size_t len,
 	cmd.rx_buf = read_buf;
 	cmd.buf_len = len;
 	ret = atmel_qspi_run_command(aq, &cmd, QSPI_IFR_TFRTYP_TRSFR_READ_MEM,
-				     ifr_width);
+				     nor->read_proto);
 	return (ret < 0) ? ret : len;
 }
 
@@ -590,6 +605,20 @@ static irqreturn_t atmel_qspi_interrupt(int irq, void *dev_id)
 
 static int atmel_qspi_probe(struct platform_device *pdev)
 {
+	const struct spi_nor_hwcaps hwcaps = {
+		.mask = SNOR_HWCAPS_READ |
+			SNOR_HWCAPS_READ_FAST |
+			SNOR_HWCAPS_READ_1_1_2 |
+			SNOR_HWCAPS_READ_1_2_2 |
+			SNOR_HWCAPS_READ_2_2_2 |
+			SNOR_HWCAPS_READ_1_1_4 |
+			SNOR_HWCAPS_READ_1_4_4 |
+			SNOR_HWCAPS_READ_4_4_4 |
+			SNOR_HWCAPS_PP |
+			SNOR_HWCAPS_PP_1_1_4 |
+			SNOR_HWCAPS_PP_1_4_4 |
+			SNOR_HWCAPS_PP_4_4_4,
+	};
 	struct device_node *child, *np = pdev->dev.of_node;
 	struct atmel_qspi *aq;
 	struct resource *res;
@@ -679,7 +708,7 @@ static int atmel_qspi_probe(struct platform_device *pdev)
 	if (err)
 		goto disable_clk;
 
-	err = spi_nor_scan(nor, NULL, SPI_NOR_QUAD);
+	err = spi_nor_scan(nor, NULL, &hwcaps);
 	if (err)
 		goto disable_clk;
 

drivers/mtd/spi-nor/cadence-quadspi.c

@@ -855,15 +855,14 @@ static int cqspi_set_protocol(struct spi_nor *nor, const int read)
 	f_pdata->data_width = CQSPI_INST_TYPE_SINGLE;
 
 	if (read) {
-		switch (nor->flash_read) {
-		case SPI_NOR_NORMAL:
-		case SPI_NOR_FAST:
+		switch (nor->read_proto) {
+		case SNOR_PROTO_1_1_1:
 			f_pdata->data_width = CQSPI_INST_TYPE_SINGLE;
 			break;
-		case SPI_NOR_DUAL:
+		case SNOR_PROTO_1_1_2:
 			f_pdata->data_width = CQSPI_INST_TYPE_DUAL;
 			break;
-		case SPI_NOR_QUAD:
+		case SNOR_PROTO_1_1_4:
 			f_pdata->data_width = CQSPI_INST_TYPE_QUAD;
 			break;
 		default:
@@ -1069,6 +1068,13 @@ static void cqspi_controller_init(struct cqspi_st *cqspi)
 
 static int cqspi_setup_flash(struct cqspi_st *cqspi, struct device_node *np)
 {
+	const struct spi_nor_hwcaps hwcaps = {
+		.mask = SNOR_HWCAPS_READ |
+			SNOR_HWCAPS_READ_FAST |
+			SNOR_HWCAPS_READ_1_1_2 |
+			SNOR_HWCAPS_READ_1_1_4 |
+			SNOR_HWCAPS_PP,
+	};
 	struct platform_device *pdev = cqspi->pdev;
 	struct device *dev = &pdev->dev;
 	struct cqspi_flash_pdata *f_pdata;
@@ -1123,7 +1129,7 @@ static int cqspi_setup_flash(struct cqspi_st *cqspi, struct device_node *np)
 			goto err;
 		}
 
-		ret = spi_nor_scan(nor, NULL, SPI_NOR_QUAD);
+		ret = spi_nor_scan(nor, NULL, &hwcaps);
 		if (ret)
 			goto err;
 

drivers/mtd/spi-nor/fsl-quadspi.c

@@ -957,6 +957,10 @@ static void fsl_qspi_unprep(struct spi_nor *nor, enum spi_nor_ops ops)
 
 static int fsl_qspi_probe(struct platform_device *pdev)
 {
+	const struct spi_nor_hwcaps hwcaps = {
+		.mask = SNOR_HWCAPS_READ_1_1_4 |
+			SNOR_HWCAPS_PP,
+	};
 	struct device_node *np = pdev->dev.of_node;
 	struct device *dev = &pdev->dev;
 	struct fsl_qspi *q;
@@ -1065,7 +1069,7 @@ static int fsl_qspi_probe(struct platform_device *pdev)
 		/* set the chip address for READID */
 		fsl_qspi_set_base_addr(q, nor);
 
-		ret = spi_nor_scan(nor, NULL, SPI_NOR_QUAD);
+		ret = spi_nor_scan(nor, NULL, &hwcaps);
 		if (ret)
 			goto mutex_failed;
 

drivers/mtd/spi-nor/hisi-sfc.c

@@ -120,19 +120,24 @@ static inline int wait_op_finish(struct hifmc_host *host)
 		(reg & FMC_INT_OP_DONE), 0, FMC_WAIT_TIMEOUT);
 }
 
-static int get_if_type(enum read_mode flash_read)
+static int get_if_type(enum spi_nor_protocol proto)
 {
 	enum hifmc_iftype if_type;
 
-	switch (flash_read) {
-	case SPI_NOR_DUAL:
+	switch (proto) {
+	case SNOR_PROTO_1_1_2:
 		if_type = IF_TYPE_DUAL;
 		break;
-	case SPI_NOR_QUAD:
+	case SNOR_PROTO_1_2_2:
+		if_type = IF_TYPE_DIO;
+		break;
+	case SNOR_PROTO_1_1_4:
 		if_type = IF_TYPE_QUAD;
 		break;
-	case SPI_NOR_NORMAL:
-	case SPI_NOR_FAST:
+	case SNOR_PROTO_1_4_4:
+		if_type = IF_TYPE_QIO;
+		break;
+	case SNOR_PROTO_1_1_1:
 	default:
 		if_type = IF_TYPE_STD;
 		break;
@@ -253,7 +258,10 @@ static int hisi_spi_nor_dma_transfer(struct spi_nor *nor, loff_t start_off,
 	writel(FMC_DMA_LEN_SET(len), host->regbase + FMC_DMA_LEN);
 
 	reg = OP_CFG_FM_CS(priv->chipselect);
-	if_type = get_if_type(nor->flash_read);
+	if (op_type == FMC_OP_READ)
+		if_type = get_if_type(nor->read_proto);
+	else
+		if_type = get_if_type(nor->write_proto);
 	reg |= OP_CFG_MEM_IF_TYPE(if_type);
 	if (op_type == FMC_OP_READ)
 		reg |= OP_CFG_DUMMY_NUM(nor->read_dummy >> 3);
@@ -321,6 +329,13 @@ static ssize_t hisi_spi_nor_write(struct spi_nor *nor, loff_t to,
 static int hisi_spi_nor_register(struct device_node *np,
 				struct hifmc_host *host)
 {
+	const struct spi_nor_hwcaps hwcaps = {
+		.mask = SNOR_HWCAPS_READ |
+			SNOR_HWCAPS_READ_FAST |
+			SNOR_HWCAPS_READ_1_1_2 |
+			SNOR_HWCAPS_READ_1_1_4 |
+			SNOR_HWCAPS_PP,
+	};
 	struct device *dev = host->dev;
 	struct spi_nor *nor;
 	struct hifmc_priv *priv;
@@ -362,7 +377,7 @@ static int hisi_spi_nor_register(struct device_node *np,
 	nor->read = hisi_spi_nor_read;
 	nor->write = hisi_spi_nor_write;
 	nor->erase = NULL;
-	ret = spi_nor_scan(nor, NULL, SPI_NOR_QUAD);
+	ret = spi_nor_scan(nor, NULL, &hwcaps);
 	if (ret)
 		return ret;
 

drivers/mtd/spi-nor/intel-spi.c

@@ -715,6 +715,11 @@ static void intel_spi_fill_partition(struct intel_spi *ispi,
 struct intel_spi *intel_spi_probe(struct device *dev,
 	struct resource *mem, const struct intel_spi_boardinfo *info)
 {
+	const struct spi_nor_hwcaps hwcaps = {
+		.mask = SNOR_HWCAPS_READ |
+			SNOR_HWCAPS_READ_FAST |
+			SNOR_HWCAPS_PP,
+	};
 	struct mtd_partition part;
 	struct intel_spi *ispi;
 	int ret;
@@ -746,7 +751,7 @@ struct intel_spi *intel_spi_probe(struct device *dev,
 	ispi->nor.write = intel_spi_write;
 	ispi->nor.erase = intel_spi_erase;
 
-	ret = spi_nor_scan(&ispi->nor, NULL, SPI_NOR_NORMAL);
+	ret = spi_nor_scan(&ispi->nor, NULL, &hwcaps);
 	if (ret) {
 		dev_info(dev, "failed to locate the chip\n");
 		return ERR_PTR(ret);

drivers/mtd/spi-nor/mtk-quadspi.c

@@ -123,20 +123,20 @@ static void mt8173_nor_set_read_mode(struct mt8173_nor *mt8173_nor)
 {
 	struct spi_nor *nor = &mt8173_nor->nor;
 
-	switch (nor->flash_read) {
-	case SPI_NOR_FAST:
+	switch (nor->read_proto) {
+	case SNOR_PROTO_1_1_1:
 		writeb(nor->read_opcode, mt8173_nor->base +
 		       MTK_NOR_PRGDATA3_REG);
 		writeb(MTK_NOR_FAST_READ, mt8173_nor->base +
 		       MTK_NOR_CFG1_REG);
 		break;
-	case SPI_NOR_DUAL:
+	case SNOR_PROTO_1_1_2:
 		writeb(nor->read_opcode, mt8173_nor->base +
 		       MTK_NOR_PRGDATA3_REG);
 		writeb(MTK_NOR_DUAL_READ_EN, mt8173_nor->base +
 		       MTK_NOR_DUAL_REG);
 		break;
-	case SPI_NOR_QUAD:
+	case SNOR_PROTO_1_1_4:
 		writeb(nor->read_opcode, mt8173_nor->base +
 		       MTK_NOR_PRGDATA4_REG);
 		writeb(MTK_NOR_QUAD_READ_EN, mt8173_nor->base +
@@ -408,6 +408,11 @@ static int mt8173_nor_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf,
 static int mtk_nor_init(struct mt8173_nor *mt8173_nor,
 			struct device_node *flash_node)
 {
+	const struct spi_nor_hwcaps hwcaps = {
+		.mask = SNOR_HWCAPS_READ_FAST |
+			SNOR_HWCAPS_READ_1_1_2 |
+			SNOR_HWCAPS_PP,
+	};
 	int ret;
 	struct spi_nor *nor;
 
@@ -426,7 +431,7 @@ static int mtk_nor_init(struct mt8173_nor *mt8173_nor,
 	nor->write_reg = mt8173_nor_write_reg;
 	nor->mtd.name = "mtk_nor";
 	/* initialized with NULL */
-	ret = spi_nor_scan(nor, NULL, SPI_NOR_DUAL);
+	ret = spi_nor_scan(nor, NULL, &hwcaps);
 	if (ret)
 		return ret;
 

drivers/mtd/spi-nor/nxp-spifi.c

@@ -240,13 +240,12 @@ static int nxp_spifi_erase(struct spi_nor *nor, loff_t offs)
 
 static int nxp_spifi_setup_memory_cmd(struct nxp_spifi *spifi)
 {
-	switch (spifi->nor.flash_read) {
-	case SPI_NOR_NORMAL:
-	case SPI_NOR_FAST:
+	switch (spifi->nor.read_proto) {
+	case SNOR_PROTO_1_1_1:
 		spifi->mcmd = SPIFI_CMD_FIELDFORM_ALL_SERIAL;
 		break;
-	case SPI_NOR_DUAL:
-	case SPI_NOR_QUAD:
+	case SNOR_PROTO_1_1_2:
+	case SNOR_PROTO_1_1_4:
 		spifi->mcmd = SPIFI_CMD_FIELDFORM_QUAD_DUAL_DATA;
 		break;
 	default:
@@ -274,7 +273,11 @@ static void nxp_spifi_dummy_id_read(struct spi_nor *nor)
 static int nxp_spifi_setup_flash(struct nxp_spifi *spifi,
 				 struct device_node *np)
 {
-	enum read_mode flash_read;
+	struct spi_nor_hwcaps hwcaps = {
+		.mask = SNOR_HWCAPS_READ |
+			SNOR_HWCAPS_READ_FAST |
+			SNOR_HWCAPS_PP,
+	};
 	u32 ctrl, property;
 	u16 mode = 0;
 	int ret;
@@ -308,13 +311,12 @@ static int nxp_spifi_setup_flash(struct nxp_spifi *spifi,
 
 	if (mode & SPI_RX_DUAL) {
 		ctrl |= SPIFI_CTRL_DUAL;
-		flash_read = SPI_NOR_DUAL;
+		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
 	} else if (mode & SPI_RX_QUAD) {
 		ctrl &= ~SPIFI_CTRL_DUAL;
-		flash_read = SPI_NOR_QUAD;
+		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
 	} else {
 		ctrl |= SPIFI_CTRL_DUAL;
-		flash_read = SPI_NOR_NORMAL;
 	}
 
 	switch (mode & (SPI_CPHA | SPI_CPOL)) {
@@ -351,7 +353,7 @@ static int nxp_spifi_setup_flash(struct nxp_spifi *spifi,
 	 */
 	nxp_spifi_dummy_id_read(&spifi->nor);
 
-	ret = spi_nor_scan(&spifi->nor, NULL, flash_read);
+	ret = spi_nor_scan(&spifi->nor, NULL, &hwcaps);
 	if (ret) {
 		dev_err(spifi->dev, "device scan failed\n");
 		return ret;

drivers/mtd/spi-nor/stm32-quadspi.c

@@ -192,15 +192,15 @@ static void stm32_qspi_set_framemode(struct spi_nor *nor,
 	cmd->framemode = CCR_IMODE_1;
 
 	if (read) {
-		switch (nor->flash_read) {
-		case SPI_NOR_NORMAL:
-		case SPI_NOR_FAST:
+		switch (nor->read_proto) {
+		default:
+		case SNOR_PROTO_1_1_1:
 			dmode = CCR_DMODE_1;
 			break;
-		case SPI_NOR_DUAL:
+		case SNOR_PROTO_1_1_2:
 			dmode = CCR_DMODE_2;
 			break;
-		case SPI_NOR_QUAD:
+		case SNOR_PROTO_1_1_4:
 			dmode = CCR_DMODE_4;
 			break;
 		}
@@ -480,7 +480,12 @@ static void stm32_qspi_unprep(struct spi_nor *nor, enum spi_nor_ops ops)
 static int stm32_qspi_flash_setup(struct stm32_qspi *qspi,
 				  struct device_node *np)
 {
-	u32 width, flash_read, presc, cs_num, max_rate = 0;
+	struct spi_nor_hwcaps hwcaps = {
+		.mask = SNOR_HWCAPS_READ |
+			SNOR_HWCAPS_READ_FAST |
+			SNOR_HWCAPS_PP,
+	};
+	u32 width, presc, cs_num, max_rate = 0;
 	struct stm32_qspi_flash *flash;
 	struct mtd_info *mtd;
 	int ret;
@@ -499,12 +504,10 @@ static int stm32_qspi_flash_setup(struct stm32_qspi *qspi,
 		width = 1;
 
 	if (width == 4)
-		flash_read = SPI_NOR_QUAD;
+		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
 	else if (width == 2)
-		flash_read = SPI_NOR_DUAL;
-	else if (width == 1)
-		flash_read = SPI_NOR_NORMAL;
-	else
+		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
+	else if (width != 1)
 		return -EINVAL;
 
 	flash = &qspi->flash[cs_num];
@@ -539,7 +542,7 @@ static int stm32_qspi_flash_setup(struct stm32_qspi *qspi,
 	 */
 	flash->fsize = FSIZE_VAL(SZ_1K);
 
-	ret = spi_nor_scan(&flash->nor, NULL, flash_read);
+	ret = spi_nor_scan(&flash->nor, NULL, &hwcaps);
 	if (ret) {
 		dev_err(qspi->dev, "device scan failed\n");
 		return ret;

include/linux/mtd/spi-nor.h

@@ -119,13 +119,63 @@
 /* Configuration Register bits. */
 #define CR_QUAD_EN_SPAN		BIT(1)	/* Spansion Quad I/O */
 
-enum read_mode {
-	SPI_NOR_NORMAL = 0,
-	SPI_NOR_FAST,
-	SPI_NOR_DUAL,
-	SPI_NOR_QUAD,
+/* Supported SPI protocols */
+#define SNOR_PROTO_INST_MASK	GENMASK(23, 16)
+#define SNOR_PROTO_INST_SHIFT	16
+#define SNOR_PROTO_INST(_nbits)	\
+	((((unsigned long)(_nbits)) << SNOR_PROTO_INST_SHIFT) & \
+	 SNOR_PROTO_INST_MASK)
+
+#define SNOR_PROTO_ADDR_MASK	GENMASK(15, 8)
+#define SNOR_PROTO_ADDR_SHIFT	8
+#define SNOR_PROTO_ADDR(_nbits)	\
+	((((unsigned long)(_nbits)) << SNOR_PROTO_ADDR_SHIFT) & \
+	 SNOR_PROTO_ADDR_MASK)
+
+#define SNOR_PROTO_DATA_MASK	GENMASK(7, 0)
+#define SNOR_PROTO_DATA_SHIFT	0
+#define SNOR_PROTO_DATA(_nbits)	\
+	((((unsigned long)(_nbits)) << SNOR_PROTO_DATA_SHIFT) & \
+	 SNOR_PROTO_DATA_MASK)
+
+#define SNOR_PROTO_STR(_inst_nbits, _addr_nbits, _data_nbits)	\
+	(SNOR_PROTO_INST(_inst_nbits) |				\
+	 SNOR_PROTO_ADDR(_addr_nbits) |				\
+	 SNOR_PROTO_DATA(_data_nbits))
+
+enum spi_nor_protocol {
+	SNOR_PROTO_1_1_1 = SNOR_PROTO_STR(1, 1, 1),
+	SNOR_PROTO_1_1_2 = SNOR_PROTO_STR(1, 1, 2),
+	SNOR_PROTO_1_1_4 = SNOR_PROTO_STR(1, 1, 4),
+	SNOR_PROTO_1_2_2 = SNOR_PROTO_STR(1, 2, 2),
+	SNOR_PROTO_1_4_4 = SNOR_PROTO_STR(1, 4, 4),
+	SNOR_PROTO_2_2_2 = SNOR_PROTO_STR(2, 2, 2),
+	SNOR_PROTO_4_4_4 = SNOR_PROTO_STR(4, 4, 4),
 };
 
+static inline u8 spi_nor_get_protocol_inst_nbits(enum spi_nor_protocol proto)
+{
+	return ((unsigned long)(proto & SNOR_PROTO_INST_MASK)) >>
+		SNOR_PROTO_INST_SHIFT;
+}
+
+static inline u8 spi_nor_get_protocol_addr_nbits(enum spi_nor_protocol proto)
+{
+	return ((unsigned long)(proto & SNOR_PROTO_ADDR_MASK)) >>
+		SNOR_PROTO_ADDR_SHIFT;
+}
+
+static inline u8 spi_nor_get_protocol_data_nbits(enum spi_nor_protocol proto)
+{
+	return ((unsigned long)(proto & SNOR_PROTO_DATA_MASK)) >>
+		SNOR_PROTO_DATA_SHIFT;
+}
+
+static inline u8 spi_nor_get_protocol_width(enum spi_nor_protocol proto)
+{
+	return spi_nor_get_protocol_data_nbits(proto);
+}
+
 #define SPI_NOR_MAX_CMD_SIZE	8
 enum spi_nor_ops {
 	SPI_NOR_OPS_READ = 0,
@@ -154,9 +204,11 @@ enum spi_nor_option_flags {
  * @read_opcode:	the read opcode
  * @read_dummy:		the dummy needed by the read operation
  * @program_opcode:	the program opcode
- * @flash_read:		the mode of the read
  * @sst_write_second:	used by the SST write operation
  * @flags:		flag options for the current SPI-NOR (SNOR_F_*)
+ * @read_proto:		the SPI protocol for read operations
+ * @write_proto:	the SPI protocol for write operations
+ * @reg_proto		the SPI protocol for read_reg/write_reg/erase operations
  * @cmd_buf:		used by the write_reg
  * @prepare:		[OPTIONAL] do some preparations for the
  *			read/write/erase/lock/unlock operations
@@ -185,7 +237,9 @@ struct spi_nor {
 	u8			read_opcode;
 	u8			read_dummy;
 	u8			program_opcode;
-	enum read_mode		flash_read;
+	enum spi_nor_protocol	read_proto;
+	enum spi_nor_protocol	write_proto;
+	enum spi_nor_protocol	reg_proto;
 	bool			sst_write_second;
 	u32			flags;
 	u8			cmd_buf[SPI_NOR_MAX_CMD_SIZE];
@@ -219,11 +273,57 @@ static inline struct device_node *spi_nor_get_flash_node(struct spi_nor *nor)
 	return mtd_get_of_node(&nor->mtd);
 }
 
+/**
+ * struct spi_nor_hwcaps - Structure for describing the hardware capabilies
+ * supported by the SPI controller (bus master).
+ * @mask:		the bitmask listing all the supported hw capabilies
+ */
+struct spi_nor_hwcaps {
+	u32	mask;
+};
+
+/*
+ *(Fast) Read capabilities.
+ * MUST be ordered by priority: the higher bit position, the higher priority.
+ * As a matter of performances, it is relevant to use Quad SPI protocols first,
+ * then Dual SPI protocols before Fast Read and lastly (Slow) Read.
+ */
+#define SNOR_HWCAPS_READ_MASK		GENMASK(7, 0)
+#define SNOR_HWCAPS_READ		BIT(0)
+#define SNOR_HWCAPS_READ_FAST		BIT(1)
+
+#define SNOR_HWCAPS_READ_DUAL		GENMASK(4, 2)
+#define SNOR_HWCAPS_READ_1_1_2		BIT(2)
+#define SNOR_HWCAPS_READ_1_2_2		BIT(3)
+#define SNOR_HWCAPS_READ_2_2_2		BIT(4)
+
+#define SNOR_HWCAPS_READ_QUAD		GENMASK(7, 5)
+#define SNOR_HWCAPS_READ_1_1_4		BIT(5)
+#define SNOR_HWCAPS_READ_1_4_4		BIT(6)
+#define SNOR_HWCAPS_READ_4_4_4		BIT(7)
+
+/*
+ * Page Program capabilities.
+ * MUST be ordered by priority: the higher bit position, the higher priority.
+ * Like (Fast) Read capabilities, Quad SPI protocols are preferred to the
+ * legacy SPI 1-1-1 protocol.
+ * Note that Dual Page Programs are not supported because there is no existing
+ * JEDEC/SFDP standard to define them. Also at this moment no SPI flash memory
+ * implements such commands.
+ */
+#define SNOR_HWCAPS_PP_MASK	GENMASK(19, 16)
+#define SNOR_HWCAPS_PP		BIT(16)
+
+#define SNOR_HWCAPS_PP_QUAD	GENMASK(19, 17)
+#define SNOR_HWCAPS_PP_1_1_4	BIT(17)
+#define SNOR_HWCAPS_PP_1_4_4	BIT(18)
+#define SNOR_HWCAPS_PP_4_4_4	BIT(19)
+
 /**
  * spi_nor_scan() - scan the SPI NOR
  * @nor:	the spi_nor structure
  * @name:	the chip type name
- * @mode:	the read mode supported by the driver
+ * @hwcaps:	the hardware capabilities supported by the controller driver
  *
  * The drivers can use this fuction to scan the SPI NOR.
  * In the scanning, it will try to get all the necessary information to
@@ -233,6 +333,7 @@ static inline struct device_node *spi_nor_get_flash_node(struct spi_nor *nor)
  *
  * Return: 0 for success, others for failure.
  */
-int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode);
+int spi_nor_scan(struct spi_nor *nor, const char *name,
+		 const struct spi_nor_hwcaps *hwcaps);
 
 #endif