mtd: nand: sunxi: fix subpage write

Implement ecc->write_subpage() to prevent core code from assigning this
hook to nand_write_subpage_hwecc(). This default implementation tries
to call ecc->hwctl() which in our case is NULL, thus leading to a NULL
pointer dereference.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index 6e319bace72405009eb5f904838ef333946756d1..f582fe41d61dac0eb2214460c1b56e132b110298 100644 (file)
--- a/drivers/mtd/nand/sunxi_nand.c
+++ b/drivers/mtd/nand/sunxi_nand.c
@@ -1352,6 +1352,36 @@ static int sunxi_nfc_hw_ecc_write_page(struct mtd_info *mtd,
        return 0;
 }
 
+static int sunxi_nfc_hw_ecc_write_subpage(struct mtd_info *mtd,
+                                         struct nand_chip *chip,
+                                         u32 data_offs, u32 data_len,
+                                         const u8 *buf, int oob_required,
+                                         int page)
+{
+       struct nand_ecc_ctrl *ecc = &chip->ecc;
+       int ret, i, cur_off = 0;
+
+       sunxi_nfc_hw_ecc_enable(mtd);
+
+       for (i = data_offs / ecc->size;
+            i < DIV_ROUND_UP(data_offs + data_len, ecc->size); i++) {
+               int data_off = i * ecc->size;
+               int oob_off = i * (ecc->bytes + 4);
+               const u8 *data = buf + data_off;
+               const u8 *oob = chip->oob_poi + oob_off;
+
+               ret = sunxi_nfc_hw_ecc_write_chunk(mtd, data, data_off, oob,
+                                                  oob_off + mtd->writesize,
+                                                  &cur_off, !i, page);
+               if (ret)
+                       return ret;
+       }
+
+       sunxi_nfc_hw_ecc_disable(mtd);
+
+       return 0;
+}
+
 static int sunxi_nfc_hw_ecc_write_page_dma(struct mtd_info *mtd,
                                           struct nand_chip *chip,
                                           const u8 *buf,
@@ -1864,7 +1894,8 @@ static int sunxi_nand_hw_ecc_ctrl_init(struct mtd_info *mtd,
                ecc->write_page = sunxi_nfc_hw_ecc_write_page;
        }
 
-       /* TODO: support DMA for raw accesses */
+       /* TODO: support DMA for raw accesses and subpage write */
+       ecc->write_subpage = sunxi_nfc_hw_ecc_write_subpage;
        ecc->read_oob_raw = nand_read_oob_std;
        ecc->write_oob_raw = nand_write_oob_std;
        ecc->read_subpage = sunxi_nfc_hw_ecc_read_subpage;