linux-kernel - [PATCH] mmc: bcm2835: Use dma_request_chan() instead dma_request_slave

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20191217112625.30715-1-peter.ujfalusi@ti.com>
Date:   Tue, 17 Dec 2019 13:26:25 +0200
From:   Peter Ujfalusi <peter.ujfalusi@...com>
To:     <ulf.hansson@...aro.org>, <f.fainelli@...il.com>,
        <rjui@...adcom.com>, <sbranden@...adcom.com>,
        <nsaenzjulienne@...e.de>
CC:     <vkoul@...nel.org>, <linux-mmc@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>,
        <bcm-kernel-feedback-list@...adcom.com>,
        <linux-rpi-kernel@...ts.infradead.org>,
        <linux-arm-kernel@...ts.infradead.org>
Subject: [PATCH] mmc: bcm2835: Use dma_request_chan() instead dma_request_slave_channel()

dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.

By using dma_request_chan() directly the driver can support deferred
probing against DMA.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@...com>
---
 drivers/mmc/host/bcm2835.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/bcm2835.c b/drivers/mmc/host/bcm2835.c
index 99f61fd2a658..3821f159d36d 100644
--- a/drivers/mmc/host/bcm2835.c
+++ b/drivers/mmc/host/bcm2835.c
@@ -1393,7 +1393,15 @@ static int bcm2835_probe(struct platform_device *pdev)
 	host->dma_chan = NULL;
 	host->dma_desc = NULL;
 
-	host->dma_chan_rxtx = dma_request_slave_channel(dev, "rx-tx");
+	host->dma_chan_rxtx = dma_request_chan(dev, "rx-tx");
+	if (IS_ERR(host->dma_chan_rxtx)) {
+		if (PTR_ERR(host->dma_chan_rxtx) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+
+		/* Ignore errors to fall back to PIO mode */
+		host->dma_chan_rxtx = NULL;
+	}
+
 
 	clk = devm_clk_get(dev, NULL);
 	if (IS_ERR(clk)) {
-- 
Peter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki