From patchwork Fri Apr 14 12:05:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joy Chakraborty X-Patchwork-Id: 13211381 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 9283FC77B6E for ; Fri, 14 Apr 2023 12:06:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229925AbjDNMF7 (ORCPT ); Fri, 14 Apr 2023 08:05:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57468 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230283AbjDNMFq (ORCPT ); Fri, 14 Apr 2023 08:05:46 -0400 Received: from mail-yw1-x114a.google.com (mail-yw1-x114a.google.com [IPv6:2607:f8b0:4864:20::114a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 17F6BA272 for ; Fri, 14 Apr 2023 05:05:41 -0700 (PDT) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-54f8d4f1ca1so88669937b3.20 for ; Fri, 14 Apr 2023 05:05:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1681473940; x=1684065940; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=mmE5jy/83AbiExum2uWOlw9WgET/yaio4sgA6DKa4Xo=; b=CRnOvexc4uGaJtlXBpBxwAWjNrG2u375+vOuoxlfqXISvkbR4BgeLVDUT99nIw2Uy6 mwS8LAsYjm1VzgPyAPlrQt+NEim2Bcw48d1C0xYxN6Eq3+zRRfDdmD20DFxn6eRMPzgv klohmurUf0OZJ9ZGBoNOdxSkQFMHRqt7VFZ7YG6sTclCI43BYxTvdApYKOHOuGNe0Uuc jvI94OIMQBVfv5hzMM+bDRy4FB9sEtW2FR5WHn3nRNcYzVsnvBTnHNpWgRculEvIwbs/ 0LEnvMaNJJQDN5W0n7z7r88h8q67/zikyGBNTl7BbSTxp7GwtHe7dSuzswJ9GKyzkigo nVZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681473940; x=1684065940; 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=mmE5jy/83AbiExum2uWOlw9WgET/yaio4sgA6DKa4Xo=; b=l5A7lgWFJoOqjhXIsVQhU/PmpwtQw1azIjIpJjUqFvXOCE1koWKSj6Q6U7MAPdjiu+ wGAeHW+ChPowudWunZGltYDu4wJMNp+e5HIt1b+0RiEE0oci4EnD8Ivm4Ydm35Up/AnZ P0gnFuA5HoTBhEdq7ktCz+S/W6qMOxCNoXosV/CW50TmbCMBWhxzIGodDtDZnow91mbl g/loYH5NqYtBdxiwF3yjJ7GUauHniGGzJFI6TubNvJGmy0iLXz9EU7PRqYlDwdrMloSU KAnL/Go8y/yQRpW5c8DBqZRqRK83OLAzJZ4wPOgoUUyWHHjUROT6sPsdpr4VMEcvgITW NIzg== X-Gm-Message-State: AAQBX9fmgb2hLlqLW2/S+7EZI0cKalHc8PJ/g0txPKZFDy1Ge+flMCj3 h9maf3mINvHfAfg9J1oiiGlbuuGNiGhUSA== X-Google-Smtp-Source: AKy350bZPbwaevptDno+qvPHOfr8KublJAUevFp8oBFM9cbUZujqK/KKIYxuICd9/bEGrNo0rrEDI6cNiwW7Mw== X-Received: from joychakr.c.googlers.com ([fda3:e722:ac3:cc00:4f:4b78:c0a8:6ea]) (user=joychakr job=sendgmr) by 2002:a25:da43:0:b0:b8a:7b2d:6556 with SMTP id n64-20020a25da43000000b00b8a7b2d6556mr3624830ybf.8.1681473940307; Fri, 14 Apr 2023 05:05:40 -0700 (PDT) Date: Fri, 14 Apr 2023 12:05:18 +0000 In-Reply-To: <20230414120520.360291-1-joychakr@google.com> Mime-Version: 1.0 References: <20230414120520.360291-1-joychakr@google.com> X-Mailer: git-send-email 2.40.0.634.g4ca3ef3211-goog Message-ID: <20230414120520.360291-4-joychakr@google.com> Subject: [PATCH v6 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 --- 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 75e1b11af7c9..e1dd13fe4fd0 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;