mtd: spinand: Extend spinand_wait() to match Linux kernel implementation

This aligns spinand_wait() with the linux kernel. Instead of calling into
spi_mem_poll_status() which is not implemented in U-Boot, we code the
polling logic and make sure that schedule() is called periodically.

Signed-off-by: Mikhail Kshevetskiy <[email protected]>
Reviewed-by: Frieder Schrempf <[email protected]>
Signed-off-by: Michael Trimarchi <[email protected]>

1 files changed, 40 insertions, 7 deletions

diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
index 34e5ac33c63..3b612bec274 100644
--- a/drivers/mtd/nand/spi/core.c
+++ b/drivers/mtd/nand/spi/core.c
@@ -32,6 +32,7 @@
 #include <linux/bug.h>
 #include <linux/mtd/spinand.h>
 #include <linux/printk.h>
+#include <linux/delay.h>
 #endif
 
 struct spinand_plat {
@@ -362,21 +363,41 @@ static int spinand_erase_op(struct spinand_device *spinand,
 	return spi_mem_exec_op(spinand->slave, &op);
 }
 
-static int spinand_wait(struct spinand_device *spinand, u8 *s)
+/**
+ * spinand_wait() - Poll memory device status
+ * @spinand: the spinand device
+ * @initial_delay_us: delay in us before starting to poll
+ * @poll_delay_us: time to sleep between reads in us
+ * @s: the pointer to variable to store the value of REG_STATUS
+ *
+ * This function polls a status register (REG_STATUS) and returns when
+ * the STATUS_READY bit is 0 or when the timeout has expired.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+static int spinand_wait(struct spinand_device *spinand,
+			unsigned long initial_delay_us,
+			unsigned long poll_delay_us,
+			u8 *s)
 {
 	unsigned long start, stop;
 	u8 status;
 	int ret;
 
+	udelay(initial_delay_us);
 	start = get_timer(0);
-	stop = 400;
+	stop = SPINAND_WAITRDY_TIMEOUT_MS;
 	do {
+		schedule();
+
 		ret = spinand_read_status(spinand, &status);
 		if (ret)
 			return ret;
 
 		if (!(status & STATUS_BUSY))
 			goto out;
+
+		udelay(poll_delay_us);
 	} while (get_timer(start) < stop);
 
 	/*
@@ -418,7 +439,10 @@ static int spinand_reset_op(struct spinand_device *spinand)
 	if (ret)
 		return ret;
 
-	return spinand_wait(spinand, NULL);
+	return spinand_wait(spinand,
+			    SPINAND_RESET_INITIAL_DELAY_US,
+			    SPINAND_RESET_POLL_DELAY_US,
+			    NULL);
 }
 
 static int spinand_lock_block(struct spinand_device *spinand, u8 lock)
@@ -466,7 +490,10 @@ static int spinand_read_page(struct spinand_device *spinand,
 	if (ret)
 		return ret;
 
-	ret = spinand_wait(spinand, &status);
+	ret = spinand_wait(spinand,
+			   SPINAND_READ_INITIAL_DELAY_US,
+			   SPINAND_READ_POLL_DELAY_US,
+			   &status);
 	if (ret < 0)
 		return ret;
 
@@ -498,9 +525,12 @@ static int spinand_write_page(struct spinand_device *spinand,
 	if (ret)
 		return ret;
 
-	ret = spinand_wait(spinand, &status);
+	ret = spinand_wait(spinand,
+			   SPINAND_WRITE_INITIAL_DELAY_US,
+			   SPINAND_WRITE_POLL_DELAY_US,
+			   &status);
 	if (!ret && (status & STATUS_PROG_FAILED))
-		ret = -EIO;
+		return -EIO;
 
 	return ret;
 }
@@ -702,7 +732,10 @@ static int spinand_erase(struct nand_device *nand, const struct nand_pos *pos)
 	if (ret)
 		return ret;
 
-	ret = spinand_wait(spinand, &status);
+	ret = spinand_wait(spinand,
+			   SPINAND_ERASE_INITIAL_DELAY_US,
+			   SPINAND_ERASE_POLL_DELAY_US,
+			   &status);
 	if (!ret && (status & STATUS_ERASE_FAILED))
 		ret = -EIO;