diff mbox series

[v3] spi: imx: fix the burst length at DMA mode and CPU mode

Message ID 20240201100115.503296-1-carlos.song@nxp.com
State New
Headers
Series [v3] spi: imx: fix the burst length at DMA mode and CPU mode |

Commit Message

Carlos Song Feb. 1, 2024, 10:01 a.m. UTC 
  From: Carlos Song <carlos.song@nxp.com>

For DMA mode, the bus width of the DMA is equal to the size of data
word, so burst length should be configured as bits per word.

For CPU mode, because of the spi transfer len is in byte, so burst
length should be configured as bits per byte * spi_imx->count.

Signed-off-by: Carlos Song <carlos.song@nxp.com>
Reviewed-by: Clark Wang <xiaoning.wang@nxp.com>
Fixes: e9b220aeacf1 ("spi: spi-imx: correctly configure burst length when using dma")
Fixes: 5f66db08cbd3 ("spi: imx: Take in account bits per word instead of assuming 8-bits")
---
Changes for V3:
- include <linux/bits.h> 
---
 drivers/spi/spi-imx.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

Comments

Carlos Song Feb. 1, 2024, 10:47 a.m. UTC | #1 
> -----Original Message-----
> From: Marc Kleine-Budde <mkl@pengutronix.de>
> Sent: Thursday, February 1, 2024 6:06 PM
> To: Carlos Song <carlos.song@nxp.com>
> Cc: broonie@kernel.org; shawnguo@kernel.org; s.hauer@pengutronix.de;
> kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>; benjamin@bigler.one;
> stefanmoring@gmail.com; linux-kernel@vger.kernel.org;
> linux-arm-kernel@lists.infradead.org; linux-spi@vger.kernel.org
> Subject: [EXT] Re: [PATCH v3] spi: imx: fix the burst length at DMA mode and CPU
> mode
>
> Caution: This is an external email. Please take care when clicking links or opening
> attachments. When in doubt, report the message using the 'Report this email'
> button
>
>
> On 01.02.2024 18:01:15, carlos.song@nxp.com wrote:
> > From: Carlos Song <carlos.song@nxp.com>
> >
> > For DMA mode, the bus width of the DMA is equal to the size of data
> > word, so burst length should be configured as bits per word.
> >
> > For CPU mode, because of the spi transfer len is in byte, so burst
> > length should be configured as bits per byte * spi_imx->count.
> >
> > Signed-off-by: Carlos Song <carlos.song@nxp.com>
> > Reviewed-by: Clark Wang <xiaoning.wang@nxp.com>
> > Fixes: e9b220aeacf1 ("spi: spi-imx: correctly configure burst length
> > when using dma")
> > Fixes: 5f66db08cbd3 ("spi: imx: Take in account bits per word instead
> > of assuming 8-bits")
> > ---
> > Changes for V3:
> > - include <linux/bits.h>
> > ---
> >  drivers/spi/spi-imx.c | 9 ++++-----
> >  1 file changed, 4 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index
> > 546cdce525fc..2a1ae7b00760 100644
> > --- a/drivers/spi/spi-imx.c
> > +++ b/drivers/spi/spi-imx.c
> > @@ -21,7 +21,7 @@
> >  #include <linux/types.h>
> >  #include <linux/of.h>
> >  #include <linux/property.h>
> > -
> > +#include <linux/bits.h>
>
> nitpick:
> Please keep the includes sorted alphabetically.
>
> >  #include <linux/dma/imx-dma.h>
>
Hi,

Hhh, thank you!
I will try my best to strictly adhere to the code format in the future!
This is a good habit and I couldn't agree more! V4 will be sent.

BR
Carlos


> Marc
>
> --
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diff mbox series

Patch

diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index 546cdce525fc..2a1ae7b00760 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -21,7 +21,7 @@ 
 #include <linux/types.h>
 #include <linux/of.h>
 #include <linux/property.h>
-
+#include <linux/bits.h>
 #include <linux/dma/imx-dma.h>
 
 #define DRIVER_NAME "spi_imx"
@@ -660,15 +660,14 @@  static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
 			<< MX51_ECSPI_CTRL_BL_OFFSET;
 	else {
 		if (spi_imx->usedma) {
-			ctrl |= (spi_imx->bits_per_word *
-				spi_imx_bytes_per_word(spi_imx->bits_per_word) - 1)
+			ctrl |= (spi_imx->bits_per_word - 1)
 				<< MX51_ECSPI_CTRL_BL_OFFSET;
 		} else {
 			if (spi_imx->count >= MX51_ECSPI_CTRL_MAX_BURST)
-				ctrl |= (MX51_ECSPI_CTRL_MAX_BURST - 1)
+				ctrl |= (MX51_ECSPI_CTRL_MAX_BURST * BITS_PER_BYTE - 1)
 						<< MX51_ECSPI_CTRL_BL_OFFSET;
 			else
-				ctrl |= (spi_imx->count * spi_imx->bits_per_word - 1)
+				ctrl |= (spi_imx->count * BITS_PER_BYTE - 1)
 						<< MX51_ECSPI_CTRL_BL_OFFSET;
 		}
 	}