Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
        Mark Brown <broonie@kernel.org>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.14 047/293] regmap: fix bulk writes on paged registers
Date:   Mon, 29 Jul 2019 21:18:58 +0200
Message-Id: <20190729190826.798989049@linuxfoundation.org>
In-Reply-To: <20190729190820.321094988@linuxfoundation.org>
References: <20190729190820.321094988@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

[ Upstream commit db057679de3e9e6a03c1bcd5aee09b0d25fd9f5b ]

On buses like SlimBus and SoundWire which does not support
gather_writes yet in regmap, A bulk write on paged register
would be silently ignored after programming page.
This is because local variable 'ret' value in regmap_raw_write_impl()
gets reset to 0 once page register is written successfully and the
code below checks for 'ret' value to be -ENOTSUPP before linearising
the write buffer to send to bus->write().

Fix this by resetting the 'ret' value to -ENOTSUPP in cases where
gather_writes() is not supported or single register write is
not possible.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/base/regmap/regmap.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 8fd08023c0f5..013d0a2b3ba0 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -1509,6 +1509,8 @@ int _regmap_raw_write(struct regmap *map, unsigned int reg,
 					     map->format.reg_bytes +
 					     map->format.pad_bytes,
 					     val, val_len);
+	else
+		ret = -ENOTSUPP;
 
 	/* If that didn't work fall back on linearising by hand. */
 	if (ret == -ENOTSUPP) {
-- 
2.20.1