sf: Enable byte program support

Enabled byte program support for sst flashes in sf.

Few controllers will only support BP, so this patch gives
a tx transfer flag to set the BP so-that sf will operate
on byte program transfer.

A new TX operation mode SPI_OPM_TX_BP is introduced for such SPI
controller to use byte program op for SST flash.

Signed-off-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>

drivers/mtd/spi/sf_internal.h

@@ -40,10 +40,13 @@ enum {
 	SECT_4K		= 1 << 0,
 	SECT_32K	= 1 << 1,
 	E_FSR		= 1 << 2,
-	WR_QPP		= 1 << 3,
+	SST_BP		= 1 << 3,
 	SST_WP		= 1 << 4,
+	WR_QPP		= 1 << 5,
 };
 
+#define SST_WR		(SST_BP | SST_WP)
+
 #define SPI_FLASH_3B_ADDR_LEN		3
 #define SPI_FLASH_CMD_LEN		(1 + SPI_FLASH_3B_ADDR_LEN)
 #define SPI_FLASH_16MB_BOUN		0x1000000

drivers/mtd/spi/sf_params.c

@@ -89,16 +89,16 @@ const struct spi_flash_params spi_flash_params_table[] = {
 	{"N25Q1024A",	   0x20bb21, 0x0,       64 * 1024,  2048, RD_FULL, WR_QPP | E_FSR | SECT_4K},
 #endif
 #ifdef CONFIG_SPI_FLASH_SST		/* SST */
-	{"SST25VF040B",	   0xbf258d, 0x0,	64 * 1024,     8, RD_NORM,          SECT_4K | SST_WP},
-	{"SST25VF080B",	   0xbf258e, 0x0,	64 * 1024,    16, RD_NORM,	    SECT_4K | SST_WP},
-	{"SST25VF016B",	   0xbf2541, 0x0,	64 * 1024,    32, RD_NORM,	    SECT_4K | SST_WP},
-	{"SST25VF032B",	   0xbf254a, 0x0,	64 * 1024,    64, RD_NORM,	    SECT_4K | SST_WP},
+	{"SST25VF040B",	   0xbf258d, 0x0,	64 * 1024,     8, RD_NORM,          SECT_4K | SST_WR},
+	{"SST25VF080B",	   0xbf258e, 0x0,	64 * 1024,    16, RD_NORM,	    SECT_4K | SST_WR},
+	{"SST25VF016B",	   0xbf2541, 0x0,	64 * 1024,    32, RD_NORM,	    SECT_4K | SST_WR},
+	{"SST25VF032B",	   0xbf254a, 0x0,	64 * 1024,    64, RD_NORM,	    SECT_4K | SST_WR},
 	{"SST25VF064C",	   0xbf254b, 0x0,	64 * 1024,   128, RD_NORM,		     SECT_4K},
-	{"SST25WF512",	   0xbf2501, 0x0,	64 * 1024,     1, RD_NORM,	    SECT_4K | SST_WP},
-	{"SST25WF010",	   0xbf2502, 0x0,	64 * 1024,     2, RD_NORM,          SECT_4K | SST_WP},
-	{"SST25WF020",	   0xbf2503, 0x0,	64 * 1024,     4, RD_NORM,	    SECT_4K | SST_WP},
-	{"SST25WF040",	   0xbf2504, 0x0,	64 * 1024,     8, RD_NORM,	    SECT_4K | SST_WP},
-	{"SST25WF080",	   0xbf2505, 0x0,	64 * 1024,    16, RD_NORM,	    SECT_4K | SST_WP},
+	{"SST25WF512",	   0xbf2501, 0x0,	64 * 1024,     1, RD_NORM,	    SECT_4K | SST_WR},
+	{"SST25WF010",	   0xbf2502, 0x0,	64 * 1024,     2, RD_NORM,          SECT_4K | SST_WR},
+	{"SST25WF020",	   0xbf2503, 0x0,	64 * 1024,     4, RD_NORM,	    SECT_4K | SST_WR},
+	{"SST25WF040",	   0xbf2504, 0x0,	64 * 1024,     8, RD_NORM,	    SECT_4K | SST_WR},
+	{"SST25WF080",	   0xbf2505, 0x0,	64 * 1024,    16, RD_NORM,	    SECT_4K | SST_WR},
 #endif
 #ifdef CONFIG_SPI_FLASH_WINBOND		/* WINBOND */
 	{"W25P80",	   0xef2014, 0x0,	64 * 1024,    16, RD_NORM,		           0},

drivers/mtd/spi/sf_probe.c

@@ -136,8 +136,12 @@ static int spi_flash_validate_params(struct spi_slave *spi, u8 *idcode,
 #ifndef CONFIG_DM_SPI_FLASH
 	flash->write = spi_flash_cmd_write_ops;
 #if defined(CONFIG_SPI_FLASH_SST)
-	if (params->flags & SST_WP)
-		flash->write = sst_write_wp;
+	if (params->flags & SST_WR) {
+		if (flash->spi->op_mode_tx & SPI_OPM_TX_BP)
+			flash->write = sst_write_bp;
+		else
+			flash->write = sst_write_wp;
+	}
 #endif
 	flash->erase = spi_flash_cmd_erase_ops;
 	flash->read = spi_flash_cmd_read_ops;

include/spi.h

@@ -34,6 +34,7 @@
 
 /* SPI TX operation modes */
 #define SPI_OPM_TX_QPP		(1 << 0)
+#define SPI_OPM_TX_BP		(1 << 1)
 
 /* SPI RX operation modes */
 #define SPI_OPM_RX_AS		(1 << 0)