From patchwork Thu Apr 27 12:33:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joy Chakraborty X-Patchwork-Id: 677677 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5FD7EC77B73 for ; Thu, 27 Apr 2023 12:33:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243781AbjD0Mdr (ORCPT ); Thu, 27 Apr 2023 08:33:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48768 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243792AbjD0Mdo (ORCPT ); Thu, 27 Apr 2023 08:33:44 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04BCA4EDC for ; Thu, 27 Apr 2023 05:33:35 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id 3f1490d57ef6-b9a6f15287eso4353672276.1 for ; Thu, 27 Apr 2023 05:33:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1682598815; x=1685190815; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=o8GsQCBaZJI/kD+802nQ+4grvsSl0JkV2Q+XulPct0A=; b=CIwS7rv0Bt1NRSpeLAH2zHX1mFDLuSSyyWHxoyQnbpJ6drNZh7T5je0G8bmM11LmtV sL2mbhnvGL7nmxnTE6+xDc4VfwbDWu/5t1acHTsWuPeOvHsVRykoUE6+pvz8q6BaKzym td3aouq+E4LHEGNotLcWdg+FDtThdDALNOnC8q5SnosK4pGYp5t0MGHPgfknsNEIVqSE EtAEPpGLrbirluU/9g7gyc2fpsW0t48xDoA4+qCWWt0zzax/0JchhEaVOcaFUPYF2FT4 D/GdvuTD+e422rsRMt+nW8BTLCXrybYZ1nCdgL6dzfzTMh+57+xMBcbVtNNg46RCkZX2 +lWA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1682598815; x=1685190815; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=o8GsQCBaZJI/kD+802nQ+4grvsSl0JkV2Q+XulPct0A=; b=TvaQDT89TgD4SFCvXFGMDr6PGptle6FsVfMbg361hK8bwNQ5Exi+hu3KrqD4De8gBb OhfvDYKgi5X+PJqOSOBnL5CdLbChj5aUYwYM4Qz1V6mqww1Cr97yEy3pma7pFyf8x/lH SXoaSKuL7+bc+jpQL8hSJO8sS7Pglv7e08MqNMjbLTtzfXG+qv4aF3IVOi6ADtkyRIes Ebl4FbZc3PzNbQLZvFr73Z8+/RtTu3fiZtMbqWt4jvnpj027FLMsiTBVfeTRzyg+r1tF ymvA4CQcP1yirJV8CAODiGwSPhfT4h9blTRMbyfKQrurZ/hUaqCWciTUp05Hu8QruCxV f3bQ== X-Gm-Message-State: AC+VfDwoN2DAiBzXx35K0OfA4EiP/y6hvXL7BGWyY94jiQm3oD8T3DHS rhY2FHXq/YXe37o+sAv4b7nSWh0SAAT4yw== X-Google-Smtp-Source: ACHHUZ7dGt3m0BH4d6R7Es7xe/L3JTq8vbJ+EbpYa0o9nvD4cehchfM9KGMPtjXE8smT3s/sOphJXPEOZ3PWWw== X-Received: from joychakr.c.googlers.com ([fda3:e722:ac3:cc00:4f:4b78:c0a8:6ea]) (user=joychakr job=sendgmr) by 2002:a5b:ac5:0:b0:b8f:5b11:6d6c with SMTP id a5-20020a5b0ac5000000b00b8f5b116d6cmr3736264ybr.1.1682598815226; Thu, 27 Apr 2023 05:33:35 -0700 (PDT) Date: Thu, 27 Apr 2023 12:33:12 +0000 In-Reply-To: <20230427123314.1997152-1-joychakr@google.com> Mime-Version: 1.0 References: <20230427123314.1997152-1-joychakr@google.com> X-Mailer: git-send-email 2.40.1.495.gc816e09b53d-goog Message-ID: <20230427123314.1997152-4-joychakr@google.com> Subject: [PATCH v9 3/5] spi: dw: Add DMA directional capability check From: Joy Chakraborty To: Serge Semin , Mark Brown , Andy Shevchenko Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, manugautam@google.com, rohitner@google.com, Joy Chakraborty Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org Check capabilities of DMA controller during init to make sure it is capable of handling MEM2DEV for tx channel, DEV2MEM for rx channel. Current DW DMA driver requires both tx and rx channel to be configured and functional for any kind of transfers to take effect including half duplex. Hence, check for both tx and rx direction and fail on unavailbility of either. Signed-off-by: Joy Chakraborty Reviewed-by: Serge Semin Tested-by: Serge Semin * tested on Baikal-T1 based system with DW SPI-looped back interface transferring a chunk of data with DFS:8,12,16. --- drivers/spi/spi-dw-dma.c | 39 ++++++++++++++++++++++++++++++--------- 1 file changed, 30 insertions(+), 9 deletions(-) diff --git a/drivers/spi/spi-dw-dma.c b/drivers/spi/spi-dw-dma.c index f19c092920a1..22d0727a3789 100644 --- a/drivers/spi/spi-dw-dma.c +++ b/drivers/spi/spi-dw-dma.c @@ -72,12 +72,22 @@ static void dw_spi_dma_maxburst_init(struct dw_spi *dws) dw_writel(dws, DW_SPI_DMATDLR, dws->txburst); } -static void dw_spi_dma_sg_burst_init(struct dw_spi *dws) +static int dw_spi_dma_caps_init(struct dw_spi *dws) { - struct dma_slave_caps tx = {0}, rx = {0}; + struct dma_slave_caps tx, rx; + int ret; + + ret = dma_get_slave_caps(dws->txchan, &tx); + if (ret) + return ret; + + ret = dma_get_slave_caps(dws->rxchan, &rx); + if (ret) + return ret; - dma_get_slave_caps(dws->txchan, &tx); - dma_get_slave_caps(dws->rxchan, &rx); + if (!(tx.directions & BIT(DMA_MEM_TO_DEV) && + rx.directions & BIT(DMA_DEV_TO_MEM))) + return -ENXIO; if (tx.max_sg_burst > 0 && rx.max_sg_burst > 0) dws->dma_sg_burst = min(tx.max_sg_burst, rx.max_sg_burst); @@ -95,6 +105,7 @@ static int dw_spi_dma_init_mfld(struct device *dev, struct dw_spi *dws) struct dw_dma_slave dma_rx = { .src_id = 0 }, *rx = &dma_rx; struct pci_dev *dma_dev; dma_cap_mask_t mask; + int ret = -EBUSY; /* * Get pci device for DMA controller, currently it could only @@ -124,20 +135,25 @@ static int dw_spi_dma_init_mfld(struct device *dev, struct dw_spi *dws) init_completion(&dws->dma_completion); - dw_spi_dma_maxburst_init(dws); + ret = dw_spi_dma_caps_init(dws); + if (ret) + goto free_txchan; - dw_spi_dma_sg_burst_init(dws); + dw_spi_dma_maxburst_init(dws); pci_dev_put(dma_dev); return 0; +free_txchan: + dma_release_channel(dws->txchan); + dws->txchan = NULL; free_rxchan: dma_release_channel(dws->rxchan); dws->rxchan = NULL; err_exit: pci_dev_put(dma_dev); - return -EBUSY; + return ret; } static int dw_spi_dma_init_generic(struct device *dev, struct dw_spi *dws) @@ -163,12 +179,17 @@ static int dw_spi_dma_init_generic(struct device *dev, struct dw_spi *dws) init_completion(&dws->dma_completion); - dw_spi_dma_maxburst_init(dws); + ret = dw_spi_dma_caps_init(dws); + if (ret) + goto free_txchan; - dw_spi_dma_sg_burst_init(dws); + dw_spi_dma_maxburst_init(dws); return 0; +free_txchan: + dma_release_channel(dws->txchan); + dws->txchan = NULL; free_rxchan: dma_release_channel(dws->rxchan); dws->rxchan = NULL;