From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x22640s5dYCtDyDb905DtJNep2bBCMcp+m/FTSIcDHl/NsowuobFeEDLWh/mE2t0VypsRJx4c ARC-Seal: i=1; a=rsa-sha256; t=1518708477; cv=none; d=google.com; s=arc-20160816; b=L3y5LwrQ6aDLEs5RxOMLn483+V16HZpU1D7c8PRsQ34y93ATfj2jjouzxizWstcDjw 7IiMYmE1qvvP58fdEtfk3oYzBywg7SIZbNDxsZUuteAvmpiuTLsB5AFpaVOh7Dw4P7vY jZRn/eoNNBTwuBoUmL5/PlCH7poneZiW+veUGdREWJH5seH6ovcSLJwgqJ6gW/XDohzX 0vhLBnn0hW4b6ac4QuagPN1Y+2ph41SSa638d3msLF0LV0eVLXiIUS1cXgxYVJYqOLob IKFY+a781afRIbfuPJ0Ub3YUA6/mp/ggnWgJOcNx6ld83J7Zmpm6A9AXPiu6F3WD9Gwz QdQw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=1a4HLX3OWDhTRVEXRtJ7+uTdAImBP/pdsYOWsDp7inY=; b=bq+tAYieZ7ltM99mLYYAjbMVi2e9Hx02fwY06Rk0npJUS/76h0muOVOE9FvC9Kt75n xbk9RcQfmRayJjzxeTtRu6XSumXVhmGbfMOkzfSBwgMPLMAY4KWfKPa5HwFyAJvyZoot ARRDBN7aUNuhEq8juSP6/99by59XdcN5/oEP7gvixCmKWNUbfKg35CMBZkuukXtHpcWY eODVQyA7hSJ9fjssIRI3i/VdEwQduseyWGjrTb+IEhLX7qyBodVMoj1YPWAdl22VTQao 5kZj0co1r1hsXi8DqQwlwUqgCMda1LLY59jBuT2IzgI24xk56vZ9x/7GH9uL6KcOqy/a EbTA== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, John Keeping , Mark Brown Subject: [PATCH 4.9 55/88] ASoC: rockchip: i2s: fix playback after runtime resume Date: Thu, 15 Feb 2018 16:17:22 +0100 Message-Id: <20180215151230.342425962@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180215151222.437136975@linuxfoundation.org> References: <20180215151222.437136975@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1592481260348588269?= X-GMAIL-MSGID: =?utf-8?q?1592481260348588269?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: John Keeping commit c66234cfedfc3e6e3b62563a5f2c1562be09a35d upstream. When restoring registers during runtime resume, we must not write to I2S_TXDR which is the transmit FIFO as this queues up a sample to be output and pushes all of the output channels down by one. This can be demonstrated with the speaker-test utility: for i in a b c; do speaker-test -c 2 -s 1; done which should play a test through the left speaker three times but if the I2S hardware starts runtime suspended the first sample will be played through the right speaker. Fix this by marking I2S_TXDR as volatile (which also requires marking it as readble, even though it technically isn't). This seems to be the most robust fix, the alternative of giving I2S_TXDR a default value is more fragile since it does not prevent regcache writing to the register in all circumstances. While here, also fix the configuration of I2S_RXDR and I2S_FIFOLR; these are not writable so they do not suffer from the same problem as I2S_TXDR but reading from I2S_RXDR does suffer from a similar problem. Fixes: f0447f6cbb20 ("ASoC: rockchip: i2s: restore register during runtime_suspend/resume cycle", 2016-09-07) Signed-off-by: John Keeping Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- sound/soc/rockchip/rockchip_i2s.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/sound/soc/rockchip/rockchip_i2s.c +++ b/sound/soc/rockchip/rockchip_i2s.c @@ -476,6 +476,7 @@ static bool rockchip_i2s_rd_reg(struct d case I2S_INTCR: case I2S_XFER: case I2S_CLR: + case I2S_TXDR: case I2S_RXDR: case I2S_FIFOLR: case I2S_INTSR: @@ -490,6 +491,9 @@ static bool rockchip_i2s_volatile_reg(st switch (reg) { case I2S_INTSR: case I2S_CLR: + case I2S_FIFOLR: + case I2S_TXDR: + case I2S_RXDR: return true; default: return false; @@ -499,6 +503,8 @@ static bool rockchip_i2s_volatile_reg(st static bool rockchip_i2s_precious_reg(struct device *dev, unsigned int reg) { switch (reg) { + case I2S_RXDR: + return true; default: return false; }