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From:   Yu-Hsuan Hsu <yuhsuan@chromium.org>
To:     linux-kernel@vger.kernel.org
Cc:     Benson Leung <bleung@chromium.org>,
        Enric Balletbo i Serra <enric.balletbo@collabora.com>,
        Guenter Roeck <groeck@chromium.org>,
        Cheng-Yi Chiang <cychiang@chromium.org>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Jaroslav Kysela <perex@perex.cz>,
        Takashi Iwai <tiwai@suse.com>,
        Prashant Malani <pmalani@chromium.org>,
        Pi-Hsun Shih <pihsun@chromium.org>,
        Yu-Hsuan Hsu <yuhsuan@chromium.org>,
        "Gustavo A . R . Silva" <gustavoars@kernel.org>,
        alsa-devel@alsa-project.org
Subject: [PATCH 2/2] ASoC: cros_ec_codec: Reset I2S RX when probing
Date:   Thu,  7 Jan 2021 16:59:42 +0800
Message-Id: <20210107085942.2891525-2-yuhsuan@chromium.org>
In-Reply-To: <20210107085942.2891525-1-yuhsuan@chromium.org>
References: <20210107085942.2891525-1-yuhsuan@chromium.org>
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It is not guaranteed that I2S RX is disabled when the kernel booting.
For example, if the kernel crashes while it is enabled, it will keep
enabled until the next time EC reboots. Reset I2S RX when probing to
fix this issue.

Signed-off-by: Yu-Hsuan Hsu <yuhsuan@chromium.org>
---
 sound/soc/codecs/cros_ec_codec.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/sound/soc/codecs/cros_ec_codec.c b/sound/soc/codecs/cros_ec_codec.c
index f33a2a9654e7..28b3e2c48c86 100644
--- a/sound/soc/codecs/cros_ec_codec.c
+++ b/sound/soc/codecs/cros_ec_codec.c
@@ -1011,6 +1011,13 @@ static int cros_ec_codec_platform_probe(struct platform_device *pdev)
 	}
 	priv->ec_capabilities = r.capabilities;
 
+	/* Reset EC codec i2s rx. */
+	p.cmd = EC_CODEC_I2S_RX_RESET;
+	ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_I2S_RX,
+				   (uint8_t *)&p, sizeof(p), NULL, 0);
+	if (ret)
+		dev_warn(dev, "failed to EC_CODEC_I2S_RESET: %d\n", ret);
+
 	platform_set_drvdata(pdev, priv);
 
 	ret = devm_snd_soc_register_component(dev, &i2s_rx_component_driver,
-- 
2.29.2.729.g45daf8777d-goog