[PATCH v2 2/4] mtd: rawnand: Add support Macronix Block Protection function

[Mason Yang <masonccyang@mxic.com.tw>]

Macronix AC series support using SET_FEATURES to change
Block Protection and Unprotection.

Signed-off-by: Mason Yang <masonccyang@mxic.com.tw>
---
 drivers/mtd/nand/raw/nand_macronix.c | 69 +++++++++++++++++++++++++++++++++---
 1 file changed, 65 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/nand/raw/nand_macronix.c b/drivers/mtd/nand/raw/nand_macronix.c
index 58511ae..13929bf 100644
--- a/drivers/mtd/nand/raw/nand_macronix.c
+++ b/drivers/mtd/nand/raw/nand_macronix.c
@@ -11,6 +11,10 @@
 #define MACRONIX_READ_RETRY_BIT BIT(0)
 #define MACRONIX_NUM_READ_RETRY_MODES 6
 
+#define ONFI_FEATURE_ADDR_MXIC_PROTECTION 0xA0
+#define MXIC_BLOCK_PROTECTION_ALL_LOCK 0x38
+#define MXIC_BLOCK_PROTECTION_ALL_UNLOCK 0x0
+
 struct nand_onfi_vendor_macronix {
 	u8 reserved;
 	u8 reliability_func;
@@ -57,7 +61,7 @@ static void macronix_nand_onfi_init(struct nand_chip *chip)
  * the timings unlike what is declared in the parameter page. Unflag
  * this feature to avoid unnecessary downturns.
  */
-static void macronix_nand_fix_broken_get_timings(struct nand_chip *chip)
+static int macronix_nand_fix_broken_get_timings(struct nand_chip *chip)
 {
 	unsigned int i;
 	static const char * const broken_get_timings[] = {
@@ -78,7 +82,7 @@ static void macronix_nand_fix_broken_get_timings(struct nand_chip *chip)
 	};
 
 	if (!chip->parameters.supports_set_get_features)
-		return;
+		return 0;
 
 	for (i = 0; i < ARRAY_SIZE(broken_get_timings); i++) {
 		if (!strcmp(broken_get_timings[i], chip->parameters.model))
@@ -86,22 +90,79 @@ static void macronix_nand_fix_broken_get_timings(struct nand_chip *chip)
 	}
 
 	if (i == ARRAY_SIZE(broken_get_timings))
-		return;
+		return 0;
 
 	bitmap_clear(chip->parameters.get_feature_list,
 		     ONFI_FEATURE_ADDR_TIMING_MODE, 1);
 	bitmap_clear(chip->parameters.set_feature_list,
 		     ONFI_FEATURE_ADDR_TIMING_MODE, 1);
+	return 1;
+}
+
+/*
+ * Macronix NAND supports Block Protection by Protectoin(PT) pin;
+ * active high at power-on which protects the entire chip even the #WP is
+ * disabled. Lock/unlock protection area can be partition according to
+ * protection bits, i.e. upper 1/2 locked, upper 1/4 locked and so on.
+ */
+static int mxic_nand_lock(struct nand_chip *chip, loff_t ofs, uint64_t len)
+{
+	u8 feature[ONFI_SUBFEATURE_PARAM_LEN];
+	int ret;
+
+	feature[0] = MXIC_BLOCK_PROTECTION_ALL_LOCK;
+	nand_select_target(chip, 0);
+	ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_PROTECTION,
+				feature);
+	nand_deselect_target(chip);
+	if (ret)
+		pr_err("%s all blocks failed\n", __func__);
+
+	return ret;
+}
+
+static int mxic_nand_unlock(struct nand_chip *chip, loff_t ofs, uint64_t len)
+{
+	u8 feature[ONFI_SUBFEATURE_PARAM_LEN];
+	int ret;
+
+	feature[0] = MXIC_BLOCK_PROTECTION_ALL_UNLOCK;
+	nand_select_target(chip, 0);
+	ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_PROTECTION,
+				feature);
+	nand_deselect_target(chip);
+	if (ret)
+		pr_err("%s all blocks failed\n", __func__);
+
+	return ret;
 }
 
+/*
+ * Macronix NAND AC series support Block Protection by SET_FEATURES
+ * to lock/unlock blocks.
+ */
 static int macronix_nand_init(struct nand_chip *chip)
 {
+	bool blockprotected = false;
+
 	if (nand_is_slc(chip))
 		chip->options |= NAND_BBM_FIRSTPAGE | NAND_BBM_SECONDPAGE;
 
-	macronix_nand_fix_broken_get_timings(chip);
+	if (macronix_nand_fix_broken_get_timings(chip))
+		blockprotected = true;
+
 	macronix_nand_onfi_init(chip);
 
+	if (blockprotected) {
+		bitmap_set(chip->parameters.set_feature_list,
+			   ONFI_FEATURE_ADDR_MXIC_PROTECTION, 1);
+		bitmap_set(chip->parameters.get_feature_list,
+			   ONFI_FEATURE_ADDR_MXIC_PROTECTION, 1);
+
+		chip->_lock = mxic_nand_lock;
+		chip->_unlock = mxic_nand_unlock;
+	}
+
 	return 0;
 }
 
-- 
1.9.1