From patchwork Fri May 12 10:47:43 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joy Chakraborty X-Patchwork-Id: 13239119 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 0DEFBC77B7C for ; Fri, 12 May 2023 10:48:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240892AbjELKsp (ORCPT ); Fri, 12 May 2023 06:48:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48138 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240604AbjELKsd (ORCPT ); Fri, 12 May 2023 06:48:33 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 02F4613C23 for ; Fri, 12 May 2023 03:47:57 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 3f1490d57ef6-b9dcfade347so17824942276.2 for ; Fri, 12 May 2023 03:47:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1683888477; x=1686480477; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=VXKFUpKr0w+nTlVz7d6efsfYj1wpJ5Pn5dWHxsHWrQ4=; b=2tPLx5Jn2d88GYhqypiMnQ2nPJnhEzg90y22Gv4K0TcTBV8rNgHMc1a3U1sXfd+LQq z5Ls5cmFRvVt8gwQeReN/GPkZo9/vhpQww15PjmkoGyKQkOtwM9X6Yji4b1aKSNfknb5 h5EZHVF+d38m6iFRutc14n+dwx4SoJGiNz8XQNSlk86gC+ngVKNWMVECUejkDTX62zli FI1QqMk74Caf6djSkSfO0TKw3LQTheAW1oBhvdMi0pc/0PU/x1jSN+AhuFmXebl06JlE LjBcSLbVr6aAAGuacOuvV6IDEGDvq6V/2IcwV5/cczyY0xoEbLuD7rAf/ZTW4bZrZ3sJ iRcw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683888477; x=1686480477; 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=VXKFUpKr0w+nTlVz7d6efsfYj1wpJ5Pn5dWHxsHWrQ4=; b=DYq4KRIsbXFXAxuPkktq4UOgCz7EzZQeIx2bON7O2/k9HgIWw61Ngwi/VzNKNBaXh0 pxO5VT9l0ArpKTm7FAAsOZQXtuq82C5TwWiCoI7ecMdeCa3k24O9BSqhJkz2367f9cvd 94eKsBB+Uil+M0SCB3Owa++kCrUXl/cJJU45tbssZUg0ExAcdT58L7aeBNEtFz/FyEY0 0LPEnh0WIylhpO5Oz3RE0Z7KlUZMyP8oIK3lGqRwDL93q5JRJDGVTsHvb/Kvryw1gWbg kOUIQbPqUe3xiQSDY4b2ZMnDQZAKMegE52QjACX8wX6+DOomd6B0X+OxiAFah14zBr3T cY0w== X-Gm-Message-State: AC+VfDy6LqOLH6tOnjqVO2ovlLBFBqMVKOEG+V6LPArEw51zP4fQV7TU lFTtUFVpiL14v1XjqH5MFE6c//k7e8SKpg== X-Google-Smtp-Source: ACHHUZ5DZpq6O0qfapM2kZvNLUUraxLwadXw3ripk4FhZBHvowP3EBUHy1cS3nlWegoik/bN6pkcnMYgfInKfw== X-Received: from joychakr.c.googlers.com ([fda3:e722:ac3:cc00:4f:4b78:c0a8:6ea]) (user=joychakr job=sendgmr) by 2002:a25:5454:0:b0:ba2:1a28:c852 with SMTP id i81-20020a255454000000b00ba21a28c852mr9966526ybb.7.1683888477042; Fri, 12 May 2023 03:47:57 -0700 (PDT) Date: Fri, 12 May 2023 10:47:43 +0000 In-Reply-To: <20230512104746.1797865-1-joychakr@google.com> Mime-Version: 1.0 References: <20230512104746.1797865-1-joychakr@google.com> X-Mailer: git-send-email 2.40.1.606.ga4b1b128d6-goog Message-ID: <20230512104746.1797865-2-joychakr@google.com> Subject: [PATCH v11 1/3] spi: dw: Add DMA directional capability check From: Joy Chakraborty To: Mark Brown Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, manugautam@google.com, Joy Chakraborty , Serge Semin 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 | 41 +++++++++++++++++++++++++++++++--------- 1 file changed, 32 insertions(+), 9 deletions(-) diff --git a/drivers/spi/spi-dw-dma.c b/drivers/spi/spi-dw-dma.c index f19c092920a1..2363317a0dca 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; - dma_get_slave_caps(dws->txchan, &tx); - dma_get_slave_caps(dws->rxchan, &rx); + ret = dma_get_slave_caps(dws->rxchan, &rx); + if (ret) + return ret; + + 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); @@ -87,6 +97,8 @@ static void dw_spi_dma_sg_burst_init(struct dw_spi *dws) dws->dma_sg_burst = rx.max_sg_burst; else dws->dma_sg_burst = 0; + + return 0; } static int dw_spi_dma_init_mfld(struct device *dev, struct dw_spi *dws) @@ -95,6 +107,7 @@ 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 +137,25 @@ 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 +181,17 @@ 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;