mtd: rawnand: Give the possibility to verify a read operation is supported

This can be used to discriminate between two path in the parameter
page detection: use data_in cycles (like before) if supported, use the
CHANGE READ COLUMN command otherwise.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-mtd/20200507105241.14299-9-miquel.raynal@bootlin.com

1 files changed, 29 insertions, 19 deletions

diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
index c440f11a34e9..8df864881fff 100644
--- a/drivers/mtd/nand/raw/nand_base.c
+++ b/drivers/mtd/nand/raw/nand_base.c
@@ -740,7 +740,8 @@ int nand_soft_waitrdy(struct nand_chip *chip, unsigned long timeout_ms)
 	 */
 	timeout_ms = jiffies + msecs_to_jiffies(timeout_ms) + 1;
 	do {
-		ret = nand_read_data_op(chip, &status, sizeof(status), true);
+		ret = nand_read_data_op(chip, &status, sizeof(status), true,
+					false);
 		if (ret)
 			break;
 
@@ -820,7 +821,7 @@ void panic_nand_wait(struct nand_chip *chip, unsigned long timeo)
 			u8 status;
 
 			ret = nand_read_data_op(chip, &status, sizeof(status),
-						true);
+						true, false);
 			if (ret)
 				return;
 
@@ -1918,6 +1919,8 @@ EXPORT_SYMBOL_GPL(nand_reset_op);
  * @buf: buffer used to store the data
  * @len: length of the buffer
  * @force_8bit: force 8-bit bus access
+ * @check_only: do not actually run the command, only checks if the
+ *              controller driver supports it
  *
  * This function does a raw data read on the bus. Usually used after launching
  * another NAND operation like nand_read_page_op().
@@ -1926,7 +1929,7 @@ EXPORT_SYMBOL_GPL(nand_reset_op);
  * Returns 0 on success, a negative error code otherwise.
  */
 int nand_read_data_op(struct nand_chip *chip, void *buf, unsigned int len,
-		      bool force_8bit)
+		      bool force_8bit, bool check_only)
 {
 	if (!len || !buf)
 		return -EINVAL;
@@ -1939,9 +1942,15 @@ int nand_read_data_op(struct nand_chip *chip, void *buf, unsigned int len,
 
 		instrs[0].ctx.data.force_8bit = force_8bit;
 
+		if (check_only)
+			return nand_check_op(chip, &op);
+
 		return nand_exec_op(chip, &op);
 	}
 
+	if (check_only)
+		return 0;
+
 	if (force_8bit) {
 		u8 *p = buf;
 		unsigned int i;
@@ -2670,7 +2679,7 @@ int nand_read_page_raw(struct nand_chip *chip, uint8_t *buf, int oob_required,
 
 	if (oob_required) {
 		ret = nand_read_data_op(chip, chip->oob_poi, mtd->oobsize,
-					false);
+					false, false);
 		if (ret)
 			return ret;
 	}
@@ -2702,7 +2711,7 @@ static int nand_read_page_raw_syndrome(struct nand_chip *chip, uint8_t *buf,
 		return ret;
 
 	for (steps = chip->ecc.steps; steps > 0; steps--) {
-		ret = nand_read_data_op(chip, buf, eccsize, false);
+		ret = nand_read_data_op(chip, buf, eccsize, false, false);
 		if (ret)
 			return ret;
 
@@ -2710,14 +2719,14 @@ static int nand_read_page_raw_syndrome(struct nand_chip *chip, uint8_t *buf,
 
 		if (chip->ecc.prepad) {
 			ret = nand_read_data_op(chip, oob, chip->ecc.prepad,
-						false);
+						false, false);
 			if (ret)
 				return ret;
 
 			oob += chip->ecc.prepad;
 		}
 
-		ret = nand_read_data_op(chip, oob, eccbytes, false);
+		ret = nand_read_data_op(chip, oob, eccbytes, false, false);
 		if (ret)
 			return ret;
 
@@ -2725,7 +2734,7 @@ static int nand_read_page_raw_syndrome(struct nand_chip *chip, uint8_t *buf,
 
 		if (chip->ecc.postpad) {
 			ret = nand_read_data_op(chip, oob, chip->ecc.postpad,
-						false);
+						false, false);
 			if (ret)
 				return ret;
 
@@ -2735,7 +2744,7 @@ static int nand_read_page_raw_syndrome(struct nand_chip *chip, uint8_t *buf,
 
 	size = mtd->oobsize - (oob - chip->oob_poi);
 	if (size) {
-		ret = nand_read_data_op(chip, oob, size, false);
+		ret = nand_read_data_op(chip, oob, size, false, false);
 		if (ret)
 			return ret;
 	}
@@ -2928,14 +2937,15 @@ static int nand_read_page_hwecc(struct nand_chip *chip, uint8_t *buf,
 	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 		chip->ecc.hwctl(chip, NAND_ECC_READ);
 
-		ret = nand_read_data_op(chip, p, eccsize, false);
+		ret = nand_read_data_op(chip, p, eccsize, false, false);
 		if (ret)
 			return ret;
 
 		chip->ecc.calculate(chip, p, &ecc_calc[i]);
 	}
 
-	ret = nand_read_data_op(chip, chip->oob_poi, mtd->oobsize, false);
+	ret = nand_read_data_op(chip, chip->oob_poi, mtd->oobsize, false,
+				false);
 	if (ret)
 		return ret;
 
@@ -3014,7 +3024,7 @@ static int nand_read_page_hwecc_oob_first(struct nand_chip *chip, uint8_t *buf,
 
 		chip->ecc.hwctl(chip, NAND_ECC_READ);
 
-		ret = nand_read_data_op(chip, p, eccsize, false);
+		ret = nand_read_data_op(chip, p, eccsize, false, false);
 		if (ret)
 			return ret;
 
@@ -3071,13 +3081,13 @@ static int nand_read_page_syndrome(struct nand_chip *chip, uint8_t *buf,
 
 		chip->ecc.hwctl(chip, NAND_ECC_READ);
 
-		ret = nand_read_data_op(chip, p, eccsize, false);
+		ret = nand_read_data_op(chip, p, eccsize, false, false);
 		if (ret)
 			return ret;
 
 		if (chip->ecc.prepad) {
 			ret = nand_read_data_op(chip, oob, chip->ecc.prepad,
-						false);
+						false, false);
 			if (ret)
 				return ret;
 
@@ -3086,7 +3096,7 @@ static int nand_read_page_syndrome(struct nand_chip *chip, uint8_t *buf,
 
 		chip->ecc.hwctl(chip, NAND_ECC_READSYN);
 
-		ret = nand_read_data_op(chip, oob, eccbytes, false);
+		ret = nand_read_data_op(chip, oob, eccbytes, false, false);
 		if (ret)
 			return ret;
 
@@ -3096,7 +3106,7 @@ static int nand_read_page_syndrome(struct nand_chip *chip, uint8_t *buf,
 
 		if (chip->ecc.postpad) {
 			ret = nand_read_data_op(chip, oob, chip->ecc.postpad,
-						false);
+						false, false);
 			if (ret)
 				return ret;
 
@@ -3124,7 +3134,7 @@ static int nand_read_page_syndrome(struct nand_chip *chip, uint8_t *buf,
 	/* Calculate remaining oob bytes */
 	i = mtd->oobsize - (oob - chip->oob_poi);
 	if (i) {
-		ret = nand_read_data_op(chip, oob, i, false);
+		ret = nand_read_data_op(chip, oob, i, false, false);
 		if (ret)
 			return ret;
 	}
@@ -3426,7 +3436,7 @@ static int nand_read_oob_syndrome(struct nand_chip *chip, int page)
 			sndrnd = 1;
 		toread = min_t(int, length, chunk);
 
-		ret = nand_read_data_op(chip, bufpoi, toread, false);
+		ret = nand_read_data_op(chip, bufpoi, toread, false, false);
 		if (ret)
 			return ret;
 
@@ -3434,7 +3444,7 @@ static int nand_read_oob_syndrome(struct nand_chip *chip, int page)
 		length -= toread;
 	}
 	if (length > 0) {
-		ret = nand_read_data_op(chip, bufpoi, length, false);
+		ret = nand_read_data_op(chip, bufpoi, length, false, false);
 		if (ret)
 			return ret;
 	}