mtd: devices: elm: clean elm_load_syndrome

This patch refactors elm_load_syndrome() to make it scalable for newer
ECC schemes by removing scheme specific macros (like ECC_BYTES*xx),
and instead using ECC control information passed during elm_config.

Signed-off-by: Pekon Gupta <pekon@ti.com>
Reviewed-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

2 files changed, 11 insertions, 14 deletions

diff --git a/drivers/mtd/devices/elm.c b/drivers/mtd/devices/elm.c
index c51752ad072e..4fbfaf65fabd 100644
--- a/drivers/mtd/devices/elm.c
+++ b/drivers/mtd/devices/elm.c
@@ -84,6 +84,7 @@ struct elm_info {
         struct list_head list;
         enum bch_ecc bch_type;
         struct elm_registers elm_regs;
+        int ecc_syndrome_size;
 };
 
 static LIST_HEAD(elm_devices);
@@ -126,7 +127,8 @@ int elm_config(struct device *dev, enum bch_ecc bch_type,
 
         reg_val = (bch_type & ECC_BCH_LEVEL_MASK) | (ELM_ECC_SIZE << 16);
         elm_write_reg(info, ELM_LOCATION_CONFIG, reg_val);
-        info->bch_type = bch_type;
+        info->bch_type          = bch_type;
+        info->ecc_syndrome_size = ecc_syndrome_size;
 
         return 0;
 }
@@ -175,10 +177,8 @@ static void elm_load_syndrome(struct elm_info *info,
                         elm_configure_page_mode(info, i, true);
                         offset = ELM_SYNDROME_FRAGMENT_0 +
                                 SYNDROME_FRAGMENT_REG_SIZE * i;
-
-                        /* BCH8 */
-                        if (info->bch_type) {
-
+                        switch (info->bch_type) {
+                        case BCH8_ECC:
                                 /* syndrome fragment 0 = ecc[9-12B] */
                                 val = cpu_to_be32(*(u32 *) &ecc[9]);
                                 elm_write_reg(info, offset, val);
@@ -197,7 +197,8 @@ static void elm_load_syndrome(struct elm_info *info,
                                 offset += 4;
                                 val = ecc[0];
                                 elm_write_reg(info, offset, val);
-                        } else {
+                                break;
+                        case BCH4_ECC:
                                 /* syndrome fragment 0 = ecc[20-52b] bits */
                                 val = (cpu_to_be32(*(u32 *) &ecc[3]) >> 4) |
                                         ((ecc[2] & 0xf) << 28);
@@ -207,11 +208,14 @@ static void elm_load_syndrome(struct elm_info *info,
                                 offset += 4;
                                 val = cpu_to_be32(*(u32 *) &ecc[0]) >> 12;
                                 elm_write_reg(info, offset, val);
+                                break;
+                        default:
+                                pr_err("invalid config bch_type\n");
                         }
                 }
 
                 /* Update ecc pointer with ecc byte size */
-                ecc += info->bch_type ? BCH8_SIZE : BCH4_SIZE;
+                ecc += info->ecc_syndrome_size;
         }
 }
 
diff --git a/include/linux/platform_data/elm.h b/include/linux/platform_data/elm.h
index 6e37156b0902..4edb40676b3f 100644
--- a/include/linux/platform_data/elm.h
+++ b/include/linux/platform_data/elm.h
@@ -26,13 +26,6 @@ enum bch_ecc {
 /* ELM support 8 error syndrome process */
 #define ERROR_VECTOR_MAX                8
 
-#define BCH8_ECC_OOB_BYTES              13
-#define BCH4_ECC_OOB_BYTES              7
-/* RBL requires 14 byte even though BCH8 uses only 13 byte */
-#define BCH8_SIZE                       (BCH8_ECC_OOB_BYTES + 1)
-/* Uses 1 extra byte to handle erased pages */
-#define BCH4_SIZE                       (BCH4_ECC_OOB_BYTES + 1)
-
 /**
  * struct elm_errorvec - error vector for elm
  * @error_reported:             set true for vectors error is reported