[PATCH v2 1/10] mtd: spi-nor: eliminate duplicate spi_nor_wait_till_{, fsr}_ready() code

[Brian Norris <computersforpeace@gmail.com>]

These functions were near-carbon-copies due to a small per-flash quirk.
Let's add a new spi_nor::flags bitfield to support these types of
quirks.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Cc: Graham Moore <grmoore@altera.com>
Cc: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
---
v2: replace 'sr' with 'fsr' (typo)

I think this was the only patch (of the first 7) that required changes due to
review. I may rework patch 8 eventually, but it was not meant for inclusion in
its current form.

 drivers/mtd/spi-nor/spi-nor.c | 66 ++++++++++++++++++++++---------------------
 include/linux/mtd/spi-nor.h   |  6 ++++
 2 files changed, 40 insertions(+), 32 deletions(-)

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 03e0ab8b2086..ba324e293645 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -163,48 +163,51 @@ static inline int set_4byte(struct spi_nor *nor, u32 jedec_id, int enable)
 		return nor->write_reg(nor, SPINOR_OP_BRWR, nor->cmd_buf, 1, 0);
 	}
 }
-
-static int spi_nor_wait_till_ready(struct spi_nor *nor)
+static inline int spi_nor_sr_ready(struct spi_nor *nor)
 {
-	unsigned long deadline;
-	int sr;
-
-	deadline = jiffies + MAX_READY_WAIT_JIFFIES;
-
-	do {
-		cond_resched();
+	int sr = read_sr(nor);
+	if (sr < 0)
+		return sr;
+	else
+		return !(sr & SR_WIP);
+}
 
-		sr = read_sr(nor);
-		if (sr < 0)
-			break;
-		else if (!(sr & SR_WIP))
-			return 0;
-	} while (!time_after_eq(jiffies, deadline));
+static inline int spi_nor_fsr_ready(struct spi_nor *nor)
+{
+	int fsr = read_fsr(nor);
+	if (fsr < 0)
+		return fsr;
+	else
+		return fsr & FSR_READY;
+}
 
-	return -ETIMEDOUT;
+static int spi_nor_ready(struct spi_nor *nor)
+{
+	int sr, fsr;
+	sr = spi_nor_sr_ready(nor);
+	if (sr < 0)
+		return sr;
+	fsr = nor->flags & SNOR_F_USE_FSR ? spi_nor_fsr_ready(nor) : 1;
+	if (fsr < 0)
+		return fsr;
+	return sr && fsr;
 }
 
-static int spi_nor_wait_till_fsr_ready(struct spi_nor *nor)
+static int spi_nor_wait_till_ready(struct spi_nor *nor)
 {
 	unsigned long deadline;
-	int sr;
-	int fsr;
+	int ret;
 
 	deadline = jiffies + MAX_READY_WAIT_JIFFIES;
 
 	do {
 		cond_resched();
 
-		sr = read_sr(nor);
-		if (sr < 0) {
-			break;
-		} else if (!(sr & SR_WIP)) {
-			fsr = read_fsr(nor);
-			if (fsr < 0)
-				break;
-			if (fsr & FSR_READY)
-				return 0;
-		}
+		ret = spi_nor_ready(nor);
+		if (ret < 0)
+			return ret;
+		if (ret)
+			return 0;
 	} while (!time_after_eq(jiffies, deadline));
 
 	return -ETIMEDOUT;
@@ -1009,9 +1012,8 @@ int spi_nor_scan(struct spi_nor *nor, const struct spi_device_id *id,
 	else
 		mtd->_write = spi_nor_write;
 
-	if ((info->flags & USE_FSR) &&
-	    nor->wait_till_ready == spi_nor_wait_till_ready)
-		nor->wait_till_ready = spi_nor_wait_till_fsr_ready;
+	if (info->flags & USE_FSR)
+		nor->flags |= SNOR_F_USE_FSR;
 
 	/* prefer "small sector" erase if possible */
 	if (info->flags & SECT_4K) {
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 9e6294f32ba8..603ac0306663 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -116,6 +116,10 @@ enum spi_nor_ops {
 	SPI_NOR_OPS_UNLOCK,
 };
 
+enum spi_nor_option_flags {
+	SNOR_F_USE_FSR		= BIT(0),
+};
+
 /**
  * struct spi_nor - Structure for defining a the SPI NOR layer
  * @mtd:		point to a mtd_info structure
@@ -129,6 +133,7 @@ enum spi_nor_ops {
  * @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_*)
  * @cfg:		used by the read_xfer/write_xfer
  * @cmd_buf:		used by the write_reg
  * @prepare:		[OPTIONAL] do some preparations for the
@@ -160,6 +165,7 @@ struct spi_nor {
 	u8			program_opcode;
 	enum read_mode		flash_read;
 	bool			sst_write_second;
+	u32			flags;
 	struct spi_nor_xfer_cfg	cfg;
 	u8			cmd_buf[SPI_NOR_MAX_CMD_SIZE];
 
-- 
1.9.1