From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CC9DFE54A for ; Thu, 1 Jun 2023 13:24:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 592A9C433D2; Thu, 1 Jun 2023 13:24:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1685625850; bh=cgL6P8mK4oe27gSHKHnEjDlukWGS2CkKrCne481kdR4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KFQrW1XyVMo+9jhDGDw59VbdMUU6FjSCW7AgItkNlUu7RUYfn1Z0SOJuXKe6juex4 ADj6pfHaj/xIKqv9Klve8G+M7FOVq5DPNUmLkwPLAwFwjDpn+L8YC1Tla88jkOuuOu OP/WvVCqkZKWK8dyhdfqsymx3vN9zEBiE/t24ShI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Claudiu Beznea , Vinod Koul , Sasha Levin Subject: [PATCH 5.15 18/42] dmaengine: at_xdmac: restore the content of grws register Date: Thu, 1 Jun 2023 14:21:05 +0100 Message-Id: <20230601131937.546872629@linuxfoundation.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230601131936.699199833@linuxfoundation.org> References: <20230601131936.699199833@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Claudiu Beznea [ Upstream commit 7c5eb63d16b01c202aaa95f374ae15a807745a73 ] In case the system suspends to a deep sleep state where power to DMA controller is cut-off we need to restore the content of GRWS register. This is a write only register and writing bit X tells the controller to suspend read and write requests for channel X. Thus set GRWS before restoring the content of GE (Global Enable) regiter. Fixes: e1f7c9eee707 ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver") Signed-off-by: Claudiu Beznea Link: https://lore.kernel.org/r/20230214151827.1050280-5-claudiu.beznea@microchip.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/at_xdmac.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index 4965961f55aa2..66bf570a8bd98 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -2063,6 +2063,15 @@ static int atmel_xdmac_resume(struct device *dev) if (at_xdmac_chan_is_cyclic(atchan)) { if (at_xdmac_chan_is_paused(atchan)) at_xdmac_device_resume_internal(atchan); + + /* + * We may resume from a deep sleep state where power + * to DMA controller is cut-off. Thus, restore the + * suspend state of channels set though dmaengine API. + */ + else if (at_xdmac_chan_is_paused(atchan)) + at_xdmac_device_pause_set(atxdmac, atchan); + at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, atchan->save_cnda); at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, atchan->save_cndc); at_xdmac_chan_write(atchan, AT_XDMAC_CIE, atchan->save_cim); -- 2.39.2