regulator: mt6358: Fail probe on unknown chip ID
authorChen-Yu Tsai <wenst@chromium.org>
Wed, 13 Sep 2023 08:29:16 +0000 (16:29 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 20 Nov 2023 10:59:04 +0000 (11:59 +0100)
commitc71d4b65f587c5405bf3787c907bc1a14f004d5e
tree39306be72f0bdded7e3bca29895f8a85d7b7a63a
parent5d8a3bf5dcee4e8ad185557cee50691a20a42e11
regulator: mt6358: Fail probe on unknown chip ID

[ Upstream commit 7442edec72bc657e6ce38ae01de9f10e55decfaa ]

The MT6358 and MT6366 PMICs, and likely many others from MediaTek, have
a chip ID register, making the chip semi-discoverable.

The driver currently supports two PMICs and expects to be probed on one
or the other. It does not account for incorrect mfd driver entries or
device trees. While these should not happen, if they do, it could be
catastrophic for the device. The driver should be sure the hardware is
what it expects.

Make the driver fail to probe if the chip ID presented is not a known
one.

Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Fixes: f0e3c6261af1 ("regulator: mt6366: Add support for MT6366 regulator")
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20230913082919.1631287-2-wenst@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/regulator/mt6358-regulator.c