Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Flavio Suligoi <f.suligoi@asem.it>
To:     Daniel Mack <daniel@zonque.org>,
        Haojian Zhuang <haojian.zhuang@gmail.com>,
        Robert Jarzmik <robert.jarzmik@free.fr>,
        Mark Brown <broonie@kernel.org>
CC:     <linux-arm-kernel@lists.infradead.org>,
        <linux-spi@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        Flavio Suligoi <f.suligoi@asem.it>
Subject: [PATCH 1/1] spi: pxa2xxx: change "no DMA channels..." msg from debug to warning
Date:   Fri, 5 Apr 2019 14:40:22 +0200
Message-ID: <1554468022-17416-1-git-send-email-f.suligoi@asem.it>
MIME-Version: 1.0
Content-Type: text/plain
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Change the type of the diagnostic message:

"no DMA channels available, using PIO"

from debug to warning.

The lack of an available DMA channel is very important regard the
spi-pxa2xx performance. The transfer speed can be reduced more than 50%.

So it is very important to warn the user about this, without enabling
the full SPI debug with CONFIG_SPI_DEBUG.

Moreover, enabling the full SPI debug only to enable this specific
debug message, the dmesg buffer fills quickly with a lot of
repetitive information during the SPI data transfer.
This cause the loss of all the first important messages
written during the initialization.

Signed-off-by: Flavio Suligoi <f.suligoi@asem.it>
---
 drivers/spi/spi-pxa2xx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index 6160fe0..f7068cc 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -1696,7 +1696,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
 	if (platform_info->enable_dma) {
 		status = pxa2xx_spi_dma_setup(drv_data);
 		if (status) {
-			dev_dbg(dev, "no DMA channels available, using PIO\n");
+			dev_warn(dev, "no DMA channels available, using PIO\n");
 			platform_info->enable_dma = false;
 		} else {
 			controller->can_dma = pxa2xx_spi_can_dma;
-- 
2.7.4