mtd: nand: Fix data interface configuration logic

[u-boot] / drivers / mtd / nand / nand_base.c

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index f452f59c7c18f0cb7c750e76928232bb34d41b27..5054c0e7abe387f7b55e3809cc1aa2e1a434d250 100644 (file)
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -1046,10 +1046,11 @@ static void __maybe_unused nand_release_data_interface(struct nand_chip *chip)
 /**
  * nand_reset - Reset and initialize a NAND device
  * @chip: The NAND chip
+ * @chipnr: Internal die id
  *
  * Returns 0 for success or negative error code otherwise
  */
-int nand_reset(struct nand_chip *chip)
+int nand_reset(struct nand_chip *chip, int chipnr)
 {
        struct mtd_info *mtd = nand_to_mtd(chip);
        int ret;
@@ -1058,9 +1059,17 @@ int nand_reset(struct nand_chip *chip)
        if (ret)
                return ret;
 
+       /*
+        * The CS line has to be released before we can apply the new NAND
+        * interface settings, hence this weird ->select_chip() dance.
+        */
+       chip->select_chip(mtd, chipnr);
        chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
+       chip->select_chip(mtd, -1);
 
+       chip->select_chip(mtd, chipnr);
        ret = nand_setup_data_interface(chip);
+       chip->select_chip(mtd, -1);
        if (ret)
                return ret;
 
@@ -2746,10 +2755,6 @@ static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
        }
 
        chipnr = (int)(to >> chip->chip_shift);
-       chip->select_chip(mtd, chipnr);
-
-       /* Shift to get page */
-       page = (int)(to >> chip->page_shift);
 
        /*
         * Reset the chip. Some chips (like the Toshiba TC5832DC found in one
@@ -2757,7 +2762,12 @@ static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
         * if we don't do this. I have no clue why, but I seem to have 'fixed'
         * it in the doc2000 driver in August 1999.  dwmw2.
         */
-       nand_reset(chip);
+       nand_reset(chip, chipnr);
+
+       chip->select_chip(mtd, chipnr);
+
+       /* Shift to get page */
+       page = (int)(to >> chip->page_shift);
 
        /* Check, if it is write protected */
        if (nand_check_wp(mtd)) {
@@ -3771,14 +3781,14 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
        int i, maf_idx;
        u8 id_data[8];
 
-       /* Select the device */
-       chip->select_chip(mtd, 0);
-
        /*
         * Reset the chip, required by some chips (e.g. Micron MT29FxGxxxxx)
         * after power-up.
         */
-       nand_reset(chip);
+       nand_reset(chip, 0);
+
+       /* Select the device */
+       chip->select_chip(mtd, 0);
 
        /* Send the command for reading device ID */
        chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
@@ -4033,17 +4043,31 @@ int nand_scan_ident(struct mtd_info *mtd, int maxchips,
                return PTR_ERR(type);
        }
 
+       /* Initialize the ->data_interface field. */
        ret = nand_init_data_interface(chip);
        if (ret)
                return ret;
 
+       /*
+        * Setup the data interface correctly on the chip and controller side.
+        * This explicit call to nand_setup_data_interface() is only required
+        * for the first die, because nand_reset() has been called before
+        * ->data_interface and ->default_onfi_timing_mode were set.
+        * For the other dies, nand_reset() will automatically switch to the
+        * best mode for us.
+        */
+       ret = nand_setup_data_interface(chip);
+       if (ret)
+               return ret;
+
        chip->select_chip(mtd, -1);
 
        /* Check for a chip array */
        for (i = 1; i < maxchips; i++) {
-               chip->select_chip(mtd, i);
                /* See comment in nand_get_flash_type for reset */
-               nand_reset(chip);
+               nand_reset(chip, i);
+
+               chip->select_chip(mtd, i);
                /* Send the command for reading device ID */
                chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
                /* Read manufacturer and device IDs */