linux-kernel - [PATCH v2 12/21] spi: dw: Discard chip enabling on DMA setup error

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Message-ID: <20200930185545.29959-13-Sergey.Semin@baikalelectronics.ru>
Date:   Wed, 30 Sep 2020 21:55:36 +0300
From:   Serge Semin <Sergey.Semin@...kalelectronics.ru>
To:     Mark Brown <broonie@...nel.org>
CC:     Serge Semin <Sergey.Semin@...kalelectronics.ru>,
        Serge Semin <fancer.lancer@...il.com>,
        Alexey Malahov <Alexey.Malahov@...kalelectronics.ru>,
        Ramil Zaripov <Ramil.Zaripov@...kalelectronics.ru>,
        Pavel Parkhomenko <Pavel.Parkhomenko@...kalelectronics.ru>,
        Andy Shevchenko <andy.shevchenko@...il.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Lars Povlsen <lars.povlsen@...rochip.com>,
        "wuxu . wu" <wuxu.wu@...wei.com>, Feng Tang <feng.tang@...el.com>,
        Rob Herring <robh+dt@...nel.org>, <linux-spi@...r.kernel.org>,
        <devicetree@...r.kernel.org>, <linux-kernel@...r.kernel.org>
Subject: [PATCH v2 12/21] spi: dw: Discard chip enabling on DMA setup error

It's pointless to enable the chip back if the DMA setup procedure fails,
since we'll disable it on the next transfer anyway. For the same reason We
don't do that in case of a failure detected in any other methods called
from the transfer_one() method.

While at it consider any non-zero value returned from the dma_setup
callback to be erroneous as it's supposed to be in the kernel.

Signed-off-by: Serge Semin <Sergey.Semin@...kalelectronics.ru>
---
 drivers/spi/spi-dw-core.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c
index 58a7c7465c61..fca929280aab 100644
--- a/drivers/spi/spi-dw-core.c
+++ b/drivers/spi/spi-dw-core.c
@@ -372,10 +372,8 @@ static int dw_spi_transfer_one(struct spi_controller *master,
 
 	if (dws->dma_mapped) {
 		ret = dws->dma_ops->dma_setup(dws, transfer);
-		if (ret < 0) {
-			spi_enable_chip(dws, 1);
+		if (ret)
 			return ret;
-		}
 	}
 
 	spi_enable_chip(dws, 1);
-- 
2.27.0