From: Jim Wylder Date: Wed, 17 May 2023 15:20:11 +0000 (-0500) Subject: regmap: Account for register length when chunking X-Git-Tag: v6.1.37~516 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=77ee4f8c02b803b77cc7cf19c7000d7e7de4e849;p=platform%2Fkernel%2Flinux-starfive.git regmap: Account for register length when chunking commit 3981514180c987a79ea98f0ae06a7cbf58a9ac0f upstream. Currently, when regmap_raw_write() splits the data, it uses the max_raw_write value defined for the bus. For any bus that includes the target register address in the max_raw_write value, the chunked transmission will always exceed the maximum transmission length. To avoid this problem, subtract the length of the register and the padding from the maximum transmission. Signed-off-by: Jim Wylder --- diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 7de1f27..8359164 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -2064,6 +2064,8 @@ int _regmap_raw_write(struct regmap *map, unsigned int reg, size_t val_count = val_len / val_bytes; size_t chunk_count, chunk_bytes; size_t chunk_regs = val_count; + size_t max_data = map->max_raw_write - map->format.reg_bytes - + map->format.pad_bytes; int ret, i; if (!val_count) @@ -2071,8 +2073,8 @@ int _regmap_raw_write(struct regmap *map, unsigned int reg, if (map->use_single_write) chunk_regs = 1; - else if (map->max_raw_write && val_len > map->max_raw_write) - chunk_regs = map->max_raw_write / val_bytes; + else if (map->max_raw_write && val_len > max_data) + chunk_regs = max_data / val_bytes; chunk_count = val_count / chunk_regs; chunk_bytes = chunk_regs * val_bytes;