6.5-stable review patch. If anyone has any objections, please let me know.
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From: Marek Behún kabel@kernel.org
[ Upstream commit 5652d1741574eb89cc02576e50ee3e348bd6dd77 ]
Commit c766e077d927 ("net: dsa: qca8k: convert to regmap read/write API") introduced bulk read/write methods to qca8k's regmap.
The regmap bulk read/write methods get the register address in a buffer passed as a void pointer parameter (the same buffer contains also the read/written values). The register address occupies only as many bytes as it requires at the beginning of this buffer. For example if the .reg_bits member in regmap_config is 16 (as is the case for this driver), the register address occupies only the first 2 bytes in this buffer, so it can be cast to u16.
But the original commit implementing these bulk read/write methods cast the buffer to u32: u32 reg = *(u32 *)reg_buf & U16_MAX; taking the first 4 bytes. This works on little endian systems where the first 2 bytes of the buffer correspond to the low 16-bits, but it obviously cannot work on big endian systems.
Fix this by casting the beginning of the buffer to u16 as u32 reg = *(u16 *)reg_buf;
Fixes: c766e077d927 ("net: dsa: qca8k: convert to regmap read/write API") Signed-off-by: Marek Behún kabel@kernel.org Tested-by: Christian Marangi ansuelsmth@gmail.com Reviewed-by: Christian Marangi ansuelsmth@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/dsa/qca/qca8k-8xxx.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/dsa/qca/qca8k-8xxx.c b/drivers/net/dsa/qca/qca8k-8xxx.c index efe9380d4a15d..8e1574c63954e 100644 --- a/drivers/net/dsa/qca/qca8k-8xxx.c +++ b/drivers/net/dsa/qca/qca8k-8xxx.c @@ -505,8 +505,8 @@ qca8k_bulk_read(void *ctx, const void *reg_buf, size_t reg_len, void *val_buf, size_t val_len) { int i, count = val_len / sizeof(u32), ret; - u32 reg = *(u32 *)reg_buf & U16_MAX; struct qca8k_priv *priv = ctx; + u32 reg = *(u16 *)reg_buf;
if (priv->mgmt_master && !qca8k_read_eth(priv, reg, val_buf, val_len)) @@ -527,8 +527,8 @@ qca8k_bulk_gather_write(void *ctx, const void *reg_buf, size_t reg_len, const void *val_buf, size_t val_len) { int i, count = val_len / sizeof(u32), ret; - u32 reg = *(u32 *)reg_buf & U16_MAX; struct qca8k_priv *priv = ctx; + u32 reg = *(u16 *)reg_buf; u32 *val = (u32 *)val_buf;
if (priv->mgmt_master &&