linux-kernel - [PATCH v2 2/2] regmap: fix page selection for noinc writes

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Date:   Thu, 17 Sep 2020 18:34:05 +0300
From:   Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
To:     Mark Brown <broonie@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "Rafael J. Wysocki" <rafael@...nel.org>
Cc:     Ben Whitten <ben.whitten@...il.com>, linux-kernel@...r.kernel.org
Subject: [PATCH v2 2/2] regmap: fix page selection for noinc writes

Non-incrementing writes can fail if register + length crosses page
border. However for non-incrementing writes we should not check for page
border crossing. Fix this by passing additional flag to _regmap_raw_write
and passing length to _regmap_select_page basing on the flag.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
Fixes: cdf6b11daa77 ("regmap: Add regmap_noinc_write API")
---
 drivers/base/regmap/internal.h |  2 +-
 drivers/base/regmap/regcache.c |  2 +-
 drivers/base/regmap/regmap.c   | 21 +++++++++++----------
 3 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index 3d80c4b43f72..d7c01b70e43d 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -259,7 +259,7 @@ bool regcache_set_val(struct regmap *map, void *base, unsigned int idx,
 int regcache_lookup_reg(struct regmap *map, unsigned int reg);
 
 int _regmap_raw_write(struct regmap *map, unsigned int reg,
-		      const void *val, size_t val_len);
+		      const void *val, size_t val_len, bool noinc);
 
 void regmap_async_complete_cb(struct regmap_async *async, int ret);
 
diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index a93cafd7be4f..7f4b3b62492c 100644
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -717,7 +717,7 @@ static int regcache_sync_block_raw_flush(struct regmap *map, const void **data,
 
 	map->cache_bypass = true;
 
-	ret = _regmap_raw_write(map, base, *data, count * val_bytes);
+	ret = _regmap_raw_write(map, base, *data, count * val_bytes, false);
 	if (ret)
 		dev_err(map->dev, "Unable to sync registers %#x-%#x. %d\n",
 			base, cur - map->reg_stride, ret);
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 01ecc00c8508..f102c8dc5f24 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -1464,7 +1464,7 @@ static void regmap_set_work_buf_flag_mask(struct regmap *map, int max_bytes,
 }
 
 static int _regmap_raw_write_impl(struct regmap *map, unsigned int reg,
-				  const void *val, size_t val_len)
+				  const void *val, size_t val_len, bool noinc)
 {
 	struct regmap_range_node *range;
 	unsigned long flags;
@@ -1523,7 +1523,7 @@ static int _regmap_raw_write_impl(struct regmap *map, unsigned int reg,
 				win_residue, val_len / map->format.val_bytes);
 			ret = _regmap_raw_write_impl(map, reg, val,
 						     win_residue *
-						     map->format.val_bytes);
+						     map->format.val_bytes, noinc);
 			if (ret != 0)
 				return ret;
 
@@ -1537,7 +1537,7 @@ static int _regmap_raw_write_impl(struct regmap *map, unsigned int reg,
 			win_residue = range->window_len - win_offset;
 		}
 
-		ret = _regmap_select_page(map, &reg, range, val_num);
+		ret = _regmap_select_page(map, &reg, range, noinc ? 1 : val_num);
 		if (ret != 0)
 			return ret;
 	}
@@ -1745,7 +1745,8 @@ static int _regmap_bus_raw_write(void *context, unsigned int reg,
 				      map->work_buf +
 				      map->format.reg_bytes +
 				      map->format.pad_bytes,
-				      map->format.val_bytes);
+				      map->format.val_bytes,
+				      false);
 }
 
 static inline void *_regmap_map_get_context(struct regmap *map)
@@ -1839,7 +1840,7 @@ int regmap_write_async(struct regmap *map, unsigned int reg, unsigned int val)
 EXPORT_SYMBOL_GPL(regmap_write_async);
 
 int _regmap_raw_write(struct regmap *map, unsigned int reg,
-		      const void *val, size_t val_len)
+		      const void *val, size_t val_len, bool noinc)
 {
 	size_t val_bytes = map->format.val_bytes;
 	size_t val_count = val_len / val_bytes;
@@ -1860,7 +1861,7 @@ int _regmap_raw_write(struct regmap *map, unsigned int reg,
 
 	/* Write as many bytes as possible with chunk_size */
 	for (i = 0; i < chunk_count; i++) {
-		ret = _regmap_raw_write_impl(map, reg, val, chunk_bytes);
+		ret = _regmap_raw_write_impl(map, reg, val, chunk_bytes, noinc);
 		if (ret)
 			return ret;
 
@@ -1871,7 +1872,7 @@ int _regmap_raw_write(struct regmap *map, unsigned int reg,
 
 	/* Write remaining bytes */
 	if (val_len)
-		ret = _regmap_raw_write_impl(map, reg, val, val_len);
+		ret = _regmap_raw_write_impl(map, reg, val, val_len, noinc);
 
 	return ret;
 }
@@ -1904,7 +1905,7 @@ int regmap_raw_write(struct regmap *map, unsigned int reg,
 
 	map->lock(map->lock_arg);
 
-	ret = _regmap_raw_write(map, reg, val, val_len);
+	ret = _regmap_raw_write(map, reg, val, val_len, false);
 
 	map->unlock(map->lock_arg);
 
@@ -1962,7 +1963,7 @@ int regmap_noinc_write(struct regmap *map, unsigned int reg,
 			write_len = map->max_raw_write;
 		else
 			write_len = val_len;
-		ret = _regmap_raw_write(map, reg, val, write_len);
+		ret = _regmap_raw_write(map, reg, val, write_len, true);
 		if (ret)
 			goto out_unlock;
 		val = ((u8 *)val) + write_len;
@@ -2439,7 +2440,7 @@ int regmap_raw_write_async(struct regmap *map, unsigned int reg,
 
 	map->async = true;
 
-	ret = _regmap_raw_write(map, reg, val, val_len);
+	ret = _regmap_raw_write(map, reg, val, val_len, false);
 
 	map->async = false;
 
-- 
2.28.0