From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jonas Jensen Subject: [PATCH v3] mmc: moxart: fix probe logic Date: Mon, 2 Feb 2015 16:43:06 +0100 Message-ID: <1422891786-23071-1-git-send-email-jonas.jensen@gmail.com> References: <4754899.RDUhFfxBSW@wuerfel> Return-path: Received: from mail-la0-f44.google.com ([209.85.215.44]:35913 "EHLO mail-la0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754086AbbBBPoA (ORCPT ); Mon, 2 Feb 2015 10:44:00 -0500 Received: by mail-la0-f44.google.com with SMTP id s18so42249160lam.3 for ; Mon, 02 Feb 2015 07:43:58 -0800 (PST) In-Reply-To: <4754899.RDUhFfxBSW@wuerfel> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: linux-mmc@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, arnd@arndb.de, ulf.hansson@linaro.org, linux@arm.linux.org.uk, Jonas Jensen Jonas Jensen wanted to submit a patch for these, but apparently forgot about it. I stumbled over this symptom first: drivers/built-in.o: In function `moxart_probe': :(.text+0x2af128): undefined reference to `of_dma_request_slave_channel' This is because of_dma_request_slave_channel is an internal helper and not exported to loadable module. I'm changing the driver to use dma_request_slave_channel_reason() instead. Further problems from inspection: * The remove function must not call kfree on the host pointer, because it is allocated together with the mmc_host. * The clock is never released * The dma_cap_mask_t is completely unused and can be removed * deferred probing does not work if the dma driver is loaded after the mmc driver. This patch should fix all of the above. Signed-off-by: Jonas Jensen --- Notes: This is a forward (with a single line fix) of Arnd's v2 patch. v2: do not call clk_put() on an error pointer v3: fix NULL dereference on host->clk Applies to next-20150113 drivers/mmc/host/moxart-mmc.c | 34 +++++++++++++++++++--------------- 1 file changed, 19 insertions(+), 15 deletions(-) diff --git a/drivers/mmc/host/moxart-mmc.c b/drivers/mmc/host/moxart-mmc.c index d2a1ef6..6ab57d1e 100644 --- a/drivers/mmc/host/moxart-mmc.c +++ b/drivers/mmc/host/moxart-mmc.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -131,6 +132,7 @@ struct moxart_host { struct mmc_host *mmc; struct mmc_request *mrq; struct scatterlist *cur_sg; + struct clk *clk; struct completion dma_complete; struct completion pio_complete; @@ -560,9 +562,7 @@ static int moxart_probe(struct platform_device *pdev) struct mmc_host *mmc; struct moxart_host *host = NULL; struct dma_slave_config cfg; - struct clk *clk; void __iomem *reg_mmc; - dma_cap_mask_t mask; int irq, ret; u32 i; @@ -573,6 +573,8 @@ static int moxart_probe(struct platform_device *pdev) goto out; } + host = mmc_priv(mmc); + ret = of_address_to_resource(node, 0, &res_mmc); if (ret) { dev_err(dev, "of_address_to_resource failed\n"); @@ -586,10 +588,11 @@ static int moxart_probe(struct platform_device *pdev) goto out; } - clk = of_clk_get(node, 0); - if (IS_ERR(clk)) { + host->clk = of_clk_get(node, 0); + if (IS_ERR(host->clk)) { dev_err(dev, "of_clk_get failed\n"); - ret = PTR_ERR(clk); + ret = PTR_ERR(host->clk); + host->clk = NULL; goto out; } @@ -603,18 +606,14 @@ static int moxart_probe(struct platform_device *pdev) if (ret) goto out; - dma_cap_zero(mask); - dma_cap_set(DMA_SLAVE, mask); - - host = mmc_priv(mmc); host->mmc = mmc; host->base = reg_mmc; host->reg_phys = res_mmc.start; host->timeout = msecs_to_jiffies(1000); - host->sysclk = clk_get_rate(clk); + host->sysclk = clk_get_rate(host->clk); host->fifo_width = readl(host->base + REG_FEATURE) << 2; - host->dma_chan_tx = of_dma_request_slave_channel(node, "tx"); - host->dma_chan_rx = of_dma_request_slave_channel(node, "rx"); + host->dma_chan_tx = dma_request_slave_channel_reason(dev, "tx"); + host->dma_chan_rx = dma_request_slave_channel_reason(dev, "rx"); spin_lock_init(&host->lock); @@ -624,6 +623,11 @@ static int moxart_probe(struct platform_device *pdev) mmc->ocr_avail = 0xffff00; /* Support 2.0v - 3.6v power. */ if (IS_ERR(host->dma_chan_tx) || IS_ERR(host->dma_chan_rx)) { + if (PTR_ERR(host->dma_chan_tx) == -EPROBE_DEFER || + PTR_ERR(host->dma_chan_rx) == -EPROBE_DEFER) { + ret = -EPROBE_DEFER; + goto out; + } dev_dbg(dev, "PIO mode transfer enabled\n"); host->have_dma = false; } else { @@ -677,6 +681,8 @@ static int moxart_probe(struct platform_device *pdev) return 0; out: + if (host->clk) + clk_put(host->clk); if (mmc) mmc_free_host(mmc); return ret; @@ -694,6 +700,7 @@ static int moxart_remove(struct platform_device *pdev) dma_release_channel(host->dma_chan_tx); if (!IS_ERR(host->dma_chan_rx)) dma_release_channel(host->dma_chan_rx); + clk_put(host->clk); mmc_remove_host(mmc); mmc_free_host(mmc); @@ -702,9 +709,6 @@ static int moxart_remove(struct platform_device *pdev) writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF, host->base + REG_CLOCK_CONTROL); } - - kfree(host); - return 0; } -- 1.8.2.1