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* [PATCH] spi: bcm-qspi: when tx/rx buffer is NULL set to 0
@ 2019-02-07 20:47 justinpopo6
  2019-03-31 14:40 ` Kamal Dasu
  0 siblings, 1 reply; 2+ messages in thread
From: justinpopo6 @ 2019-02-07 20:47 UTC (permalink / raw)
  To: linux-spi
  Cc: kdasu.kdev, bcm-kernel-feedback-list, broonie, linux-kernel,
	f.fainelli, Justin Chen

From: Justin Chen <justinpopo6@gmail.com>

Currently we set the tx/rx buffer to 0xff when NULL. This causes
problems with some spi slaves where 0xff is a valid command. Looking
at other drivers, the tx/rx buffer is usually set to 0x00 when NULL.
Following this convention solves the issue.

Fixes: fa236a7ef240 ("spi: bcm-qspi: Add Broadcom MSPI driver")
Signed-off-by: Justin Chen <justinpopo6@gmail.com>
---
 drivers/spi/spi-bcm-qspi.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c
index 584bcb0..79456aa 100644
--- a/drivers/spi/spi-bcm-qspi.c
+++ b/drivers/spi/spi-bcm-qspi.c
@@ -681,7 +681,7 @@ static void read_from_hw(struct bcm_qspi *qspi, int slots)
 			if (buf)
 				buf[tp.byte] = read_rxram_slot_u8(qspi, slot);
 			dev_dbg(&qspi->pdev->dev, "RD %02x\n",
-				buf ? buf[tp.byte] : 0xff);
+				buf ? buf[tp.byte] : 0x00);
 		} else {
 			u16 *buf = tp.trans->rx_buf;
 
@@ -689,7 +689,7 @@ static void read_from_hw(struct bcm_qspi *qspi, int slots)
 				buf[tp.byte / 2] = read_rxram_slot_u16(qspi,
 								      slot);
 			dev_dbg(&qspi->pdev->dev, "RD %04x\n",
-				buf ? buf[tp.byte] : 0xffff);
+				buf ? buf[tp.byte] : 0x0000);
 		}
 
 		update_qspi_trans_byte_count(qspi, &tp,
@@ -744,13 +744,13 @@ static int write_to_hw(struct bcm_qspi *qspi, struct spi_device *spi)
 	while (!tstatus && slot < MSPI_NUM_CDRAM) {
 		if (tp.trans->bits_per_word <= 8) {
 			const u8 *buf = tp.trans->tx_buf;
-			u8 val = buf ? buf[tp.byte] : 0xff;
+			u8 val = buf ? buf[tp.byte] : 0x00;
 
 			write_txram_slot_u8(qspi, slot, val);
 			dev_dbg(&qspi->pdev->dev, "WR %02x\n", val);
 		} else {
 			const u16 *buf = tp.trans->tx_buf;
-			u16 val = buf ? buf[tp.byte / 2] : 0xffff;
+			u16 val = buf ? buf[tp.byte / 2] : 0x0000;
 
 			write_txram_slot_u16(qspi, slot, val);
 			dev_dbg(&qspi->pdev->dev, "WR %04x\n", val);
-- 
2.7.4

^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH] spi: bcm-qspi: when tx/rx buffer is NULL set to 0
  2019-02-07 20:47 [PATCH] spi: bcm-qspi: when tx/rx buffer is NULL set to 0 justinpopo6
@ 2019-03-31 14:40 ` Kamal Dasu
  0 siblings, 0 replies; 2+ messages in thread
From: Kamal Dasu @ 2019-03-31 14:40 UTC (permalink / raw)
  To: justinpopo6
  Cc: linux-spi, bcm-kernel-feedback-list, Mark Brown,
	Linux Kernel Mailing List, Florian Fainelli

On Thu, Feb 7, 2019 at 3:47 PM <justinpopo6@gmail.com> wrote:
>
> From: Justin Chen <justinpopo6@gmail.com>
>
> Currently we set the tx/rx buffer to 0xff when NULL. This causes
> problems with some spi slaves where 0xff is a valid command. Looking
> at other drivers, the tx/rx buffer is usually set to 0x00 when NULL.
> Following this convention solves the issue.
>
> Fixes: fa236a7ef240 ("spi: bcm-qspi: Add Broadcom MSPI driver")
> Signed-off-by: Justin Chen <justinpopo6@gmail.com>

 Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>

> ---
>  drivers/spi/spi-bcm-qspi.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c
> index 584bcb0..79456aa 100644
> --- a/drivers/spi/spi-bcm-qspi.c
> +++ b/drivers/spi/spi-bcm-qspi.c
> @@ -681,7 +681,7 @@ static void read_from_hw(struct bcm_qspi *qspi, int slots)
>                         if (buf)
>                                 buf[tp.byte] = read_rxram_slot_u8(qspi, slot);
>                         dev_dbg(&qspi->pdev->dev, "RD %02x\n",
> -                               buf ? buf[tp.byte] : 0xff);
> +                               buf ? buf[tp.byte] : 0x00);
>                 } else {
>                         u16 *buf = tp.trans->rx_buf;
>
> @@ -689,7 +689,7 @@ static void read_from_hw(struct bcm_qspi *qspi, int slots)
>                                 buf[tp.byte / 2] = read_rxram_slot_u16(qspi,
>                                                                       slot);
>                         dev_dbg(&qspi->pdev->dev, "RD %04x\n",
> -                               buf ? buf[tp.byte] : 0xffff);
> +                               buf ? buf[tp.byte] : 0x0000);
>                 }
>
>                 update_qspi_trans_byte_count(qspi, &tp,
> @@ -744,13 +744,13 @@ static int write_to_hw(struct bcm_qspi *qspi, struct spi_device *spi)
>         while (!tstatus && slot < MSPI_NUM_CDRAM) {
>                 if (tp.trans->bits_per_word <= 8) {
>                         const u8 *buf = tp.trans->tx_buf;
> -                       u8 val = buf ? buf[tp.byte] : 0xff;
> +                       u8 val = buf ? buf[tp.byte] : 0x00;
>
>                         write_txram_slot_u8(qspi, slot, val);
>                         dev_dbg(&qspi->pdev->dev, "WR %02x\n", val);
>                 } else {
>                         const u16 *buf = tp.trans->tx_buf;
> -                       u16 val = buf ? buf[tp.byte / 2] : 0xffff;
> +                       u16 val = buf ? buf[tp.byte / 2] : 0x0000;
>
>                         write_txram_slot_u16(qspi, slot, val);
>                         dev_dbg(&qspi->pdev->dev, "WR %04x\n", val);
> --
> 2.7.4
>

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2019-03-31 14:40 UTC | newest]

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2019-02-07 20:47 [PATCH] spi: bcm-qspi: when tx/rx buffer is NULL set to 0 justinpopo6
2019-03-31 14:40 ` Kamal Dasu

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