[PATCH master 7/7] nvmem: regmap: Fix nvmem size

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

From: Robin van der Gracht <robin@protonic.nl>

We should add 1 to the max_register index since counting is zero based.

i.e. the stm32mp151 bsec has registers 0 - 95 with reg_stride 4.
Size should be (95 + 1) * 4 = 384 bytes otherwise we can't access bsec
register 95 (last one).

regmap_size_bytes() does take the +1 into account so we can use that.

Fixes: b4abbd8a6cbb ("nvmem: add nvmem_regmap_register helper")
Signed-off-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
v2 was here: https://lore.barebox.org/barebox/20240102105330.GA1318922@pengutronix.de/T/#t

v2 -> v3:
  - use regmap_size_bytes() without multiplication with stride after
    fixing its implementation.
---
 drivers/nvmem/regmap.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/nvmem/regmap.c b/drivers/nvmem/regmap.c
index fa5405d7a86a..24712fbb0f33 100644
--- a/drivers/nvmem/regmap.c
+++ b/drivers/nvmem/regmap.c
@@ -38,7 +38,7 @@ static int nvmem_regmap_read(void *ctx, unsigned offset, void *buf, size_t bytes
 	skip_bytes = offset & (stride - 1);
 	rbytes = roundup(bytes + skip_bytes, stride);
 
-	if (roffset + rbytes > stride * regmap_get_max_register(map))
+	if (roffset + rbytes > regmap_size_bytes(map))
 		return -EINVAL;
 
 	for (i = roffset; i < roffset + rbytes; i += stride) {
@@ -78,7 +78,7 @@ nvmem_regmap_register_with_pp(struct regmap *map, const char *name,
 	config.priv = map;
 	config.stride = 1;
 	config.word_size = 1;
-	config.size = regmap_get_max_register(map) * regmap_get_reg_stride(map);
+	config.size = regmap_size_bytes(map);
 	config.cell_post_process = cell_post_process;
 	config.reg_write = nvmem_regmap_write;
 	config.reg_read = nvmem_regmap_read;
-- 
2.39.2