mtd: spi-nor-core: Rework hwcaps selection

The spi-mem layer provides a spi_mem_supports_op() function to check
whether a specific operation is supported by the controller or not.
This is much more accurate than the hwcaps selection logic based on
SPI_{RX,TX}_ flags.

Rework the hwcaps selection logic to use spi_mem_supports_op().

To make sure the build doesn't break for boards not using CONFIG_DM_SPI,
add a simple SPI_{RX,TX}_ based hwcaps selection logic in spi-mem-nodm
similar to spi_mem_default_supports_op(). This change is only
compile-tested.

To avoid SPL size problems on the x530 board, the old hwcaps selection
is still kept around. Leaving the code in-place was getting difficult to
read and understand, so the code is restructured to have it all in one
isolated function. As a result of this, the parameter hwcaps to
spi_nor_setup() is no longer needed. Remove it.

Based on the Linux commit c76f5089796a (mtd: spi-nor: Rework hwcaps
selection for the spi-mem case, 2019-08-06)

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index b2e9e08..90b75ec 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -312,6 +312,20 @@
 #define SNOR_HWCAPS_PP_1_8_8	BIT(21)
 #define SNOR_HWCAPS_PP_8_8_8	BIT(22)
 
+#define SNOR_HWCAPS_X_X_X	(SNOR_HWCAPS_READ_2_2_2 |	\
+				 SNOR_HWCAPS_READ_4_4_4 |	\
+				 SNOR_HWCAPS_READ_8_8_8 |	\
+				 SNOR_HWCAPS_PP_4_4_4 |		\
+				 SNOR_HWCAPS_PP_8_8_8)
+
+#define SNOR_HWCAPS_DTR		(SNOR_HWCAPS_READ_1_1_1_DTR |	\
+				 SNOR_HWCAPS_READ_1_2_2_DTR |	\
+				 SNOR_HWCAPS_READ_1_4_4_DTR |	\
+				 SNOR_HWCAPS_READ_1_8_8_DTR)
+
+#define SNOR_HWCAPS_ALL		(SNOR_HWCAPS_READ_MASK |	\
+				 SNOR_HWCAPS_PP_MASK)
+
 struct spi_nor_read_command {
 	u8			num_mode_clocks;
 	u8			num_wait_states;
@@ -461,8 +475,7 @@
 	struct spi_nor_fixups	*fixups;
 
 	int (*setup)(struct spi_nor *nor, const struct flash_info *info,
-		     const struct spi_nor_flash_parameter *params,
-		     const struct spi_nor_hwcaps *hwcaps);
+		     const struct spi_nor_flash_parameter *params);
 	int (*prepare)(struct spi_nor *nor, enum spi_nor_ops ops);
 	void (*unprepare)(struct spi_nor *nor, enum spi_nor_ops ops);
 	int (*read_reg)(struct spi_nor *nor, u8 opcode, u8 *buf, int len);