mtd: spi-nor: move all xilinx specifics into xilinx.c

Mechanically move all the xilinx functions to its own module.

Then register the new flash specific ready() function.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220223134358.1914798-22-michael@walle.cc
diff --git a/drivers/mtd/spi-nor/xilinx.c b/drivers/mtd/spi-nor/xilinx.c
index 07dd117..05c7fe8 100644
--- a/drivers/mtd/spi-nor/xilinx.c
+++ b/drivers/mtd/spi-nor/xilinx.c
@@ -8,6 +8,27 @@
 
 #include "core.h"
 
+#define SPINOR_OP_XSE		0x50	/* Sector erase */
+#define SPINOR_OP_XPP		0x82	/* Page program */
+#define SPINOR_OP_XRDSR		0xd7	/* Read status register */
+
+#define XSR_PAGESIZE		BIT(0)	/* Page size in Po2 or Linear */
+#define XSR_RDY			BIT(7)	/* Ready */
+
+#define S3AN_INFO(_jedec_id, _n_sectors, _page_size)			\
+		.id = {							\
+			((_jedec_id) >> 16) & 0xff,			\
+			((_jedec_id) >> 8) & 0xff,			\
+			(_jedec_id) & 0xff				\
+			},						\
+		.id_len = 3,						\
+		.sector_size = (8 * (_page_size)),			\
+		.n_sectors = (_n_sectors),				\
+		.page_size = (_page_size),				\
+		.addr_width = 3,					\
+		.flags = SPI_NOR_NO_FR
+
+/* Xilinx S3AN share MFR with Atmel SPI NOR */
 static const struct flash_info xilinx_nor_parts[] = {
 	/* Xilinx S3AN Internal Flash */
 	{ "3S50AN", S3AN_INFO(0x1f2200, 64, 264) },
@@ -38,6 +59,57 @@ static u32 s3an_nor_convert_addr(struct spi_nor *nor, u32 addr)
 	return page | offset;
 }
 
+/**
+ * spi_nor_xread_sr() - Read the Status Register on S3AN flashes.
+ * @nor:	pointer to 'struct spi_nor'.
+ * @sr:		pointer to a DMA-able buffer where the value of the
+ *              Status Register will be written.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int spi_nor_xread_sr(struct spi_nor *nor, u8 *sr)
+{
+	int ret;
+
+	if (nor->spimem) {
+		struct spi_mem_op op =
+			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_XRDSR, 0),
+				   SPI_MEM_OP_NO_ADDR,
+				   SPI_MEM_OP_NO_DUMMY,
+				   SPI_MEM_OP_DATA_IN(1, sr, 0));
+
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
+		ret = spi_mem_exec_op(nor->spimem, &op);
+	} else {
+		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_XRDSR, sr,
+						      1);
+	}
+
+	if (ret)
+		dev_dbg(nor->dev, "error %d reading XRDSR\n", ret);
+
+	return ret;
+}
+
+/**
+ * spi_nor_xsr_ready() - Query the Status Register of the S3AN flash to see if
+ * the flash is ready for new commands.
+ * @nor:	pointer to 'struct spi_nor'.
+ *
+ * Return: 1 if ready, 0 if not ready, -errno on errors.
+ */
+static int spi_nor_xsr_ready(struct spi_nor *nor)
+{
+	int ret;
+
+	ret = spi_nor_xread_sr(nor, nor->bouncebuf);
+	if (ret)
+		return ret;
+
+	return !!(nor->bouncebuf[0] & XSR_RDY);
+}
+
 static int xilinx_nor_setup(struct spi_nor *nor,
 			    const struct spi_nor_hwcaps *hwcaps)
 {
@@ -83,6 +155,7 @@ static int xilinx_nor_setup(struct spi_nor *nor,
 static void xilinx_nor_late_init(struct spi_nor *nor)
 {
 	nor->params->setup = xilinx_nor_setup;
+	nor->params->ready = spi_nor_xsr_ready;
 }
 
 static const struct spi_nor_fixups xilinx_nor_fixups = {