Re: [PATCH 1/1] spi: pxa2xx: add driver enabling message

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 4/9/19 5:11 PM, Flavio Suligoi wrote:
Hi Jarkko,

Hi

On 4/8/19 6:22 PM, Flavio Suligoi wrote:
Add an info message for the PXA2xx device driver start-up,
with the indication of the transfer mode used (DMA or GPIO).

This info is useful to individuate the timing when
the module starts.

Signed-off-by: Flavio Suligoi <f.suligoi@xxxxxxx>
---
   drivers/spi/spi-pxa2xx.c | 3 +++
   1 file changed, 3 insertions(+)

diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index f7068cc..d449501 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -1826,6 +1826,9 @@ static int pxa2xx_spi_probe(struct platform_device
*pdev)
   		goto out_error_clock_enabled;
   	}

+	dev_info(dev, "PXA2xx SPI master controller (%s mode)\n",
+		 platform_info->enable_dma ? "DMA" : "PIO");
+
   	return status;

Would this look better if moved before devm_spi_register_controller()
call?

Ok, so in case of SPI registering failure, we have two messages, as:

pxa2xx-spi 80860F0E:00: PXA2xx SPI master controller (DMA mode)
pxa2xx-spi 80860F0E:00: problem registering spi controller

Do you think that it is more explicative?

I think yes and it should not cause confusion since the error message is the last one.

I was thinking the successful registration case when DMA is not available. First there is a warning, followed by a debug message from SPI core (if CONFIG_SPI_DEBUG) and then info message.

[ 9.506895] pxa2xx-spi pxa2xx-spi.13: no DMA channels available, using PIO
[    9.516770] pxa2xx-spi pxa2xx-spi.13: registered master spi2
[ 9.518527] pxa2xx-spi pxa2xx-spi.13: PXA2xx SPI master controller (PIO mode)

Actually this info message doesn't necessarily tell will the driver end up using DMA for transfers. See pxa2xx_spi_can_dma() and pxa2xx_spi_transfer_one().

How about replacing "no DMA channels available, using PIO" and have instead single info message telling is the DMA available or does the driver use PIO only?

--
Jarkko



[Index of Archives]     [Linux Kernel]     [Linux ARM (vger)]     [Linux ARM MSM]     [Linux Omap]     [Linux Arm]     [Linux Tegra]     [Fedora ARM]     [Linux for Samsung SOC]     [eCos]     [Linux Fastboot]     [Gcc Help]     [Git]     [DCCP]     [IETF Announce]     [Security]     [Linux MIPS]     [Yosemite Campsites]

  Powered by Linux