[PATCH v2] spi: rzv2h-rspi: Fix SPDR read access width for 16-bit RX

[PATCH v2] spi: rzv2h-rspi: Fix SPDR read access width for 16-bit RX

[Felix Gu]

The RZ/V2H hardware manual (section 7.5.2.2.1) specifies that read access
size for the SPI Data Register (SPDR) are fixed at 32 bits. The
RZV2H_RSPI_RX macro for the 16-bit data path used readw(), violating
this requirement.

Switch to readl() for the 16-bit RX path to conform to the hardware
specification.

Fixes: 8b61c8919dff ("spi: Add driver for the RZ/V2H(P) RSPI IP")
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
---
Changes in v2:
- Fix comments from Geert.
- Link to v1: https://patch.msgid.link/20260605-rzv2h-rspi-v1-1-c1d5ed562249@gmail.com

To: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
To: Mark Brown <broonie@kernel.org>
Cc: linux-spi@vger.kernel.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/spi/spi-rzv2h-rspi.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi-rzv2h-rspi.c b/drivers/spi/spi-rzv2h-rspi.c
index 1655efda7d20..6ed3fad873b8 100644
--- a/drivers/spi/spi-rzv2h-rspi.c
+++ b/drivers/spi/spi-rzv2h-rspi.c
@@ -135,8 +135,9 @@ static inline void rzv2h_rspi_rx_##type(struct rzv2h_rspi_priv *rspi,	\
 RZV2H_RSPI_TX(writel, u32)
 RZV2H_RSPI_TX(writew, u16)
 RZV2H_RSPI_TX(writeb, u8)
+/* The read access size for RSPI_SPDR is fixed at 32 bits */
 RZV2H_RSPI_RX(readl, u32)
-RZV2H_RSPI_RX(readw, u16)
+RZV2H_RSPI_RX(readl, u16)
 RZV2H_RSPI_RX(readl, u8)
 
 static void rzv2h_rspi_reg_rmw(const struct rzv2h_rspi_priv *rspi,

---
base-commit: a225caacc36546a09586e3ece36c0313146e7da9
change-id: 20260605-rzv2h-rspi-3c8dd168fb72

Best regards,
--  
Felix Gu <ustc.gu@gmail.com>

Re: [PATCH v2] spi: rzv2h-rspi: Fix SPDR read access width for 16-bit RX

[Geert Uytterhoeven]

On Wed, 10 Jun 2026 at 14:08, Felix Gu <ustc.gu@gmail.com> wrote:
> The RZ/V2H hardware manual (section 7.5.2.2.1) specifies that read access
> size for the SPI Data Register (SPDR) are fixed at 32 bits. The

is fixed

> RZV2H_RSPI_RX macro for the 16-bit data path used readw(), violating
> this requirement.
>
> Switch to readl() for the 16-bit RX path to conform to the hardware
> specification.
>
> Fixes: 8b61c8919dff ("spi: Add driver for the RZ/V2H(P) RSPI IP")
> Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
> Signed-off-by: Felix Gu <ustc.gu@gmail.com>
> ---
> Changes in v2:
> - Fix comments from Geert.
> - Link to v1: https://patch.msgid.link/20260605-rzv2h-rspi-v1-1-c1d5ed562249@gmail.com

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

RE: [PATCH v2] spi: rzv2h-rspi: Fix SPDR read access width for 16-bit RX

[Fabrizio Castro]

> From: Felix Gu <ustc.gu@gmail.com>
> Sent: 10 June 2026 13:08
> To: Fabrizio Castro <fabrizio.castro.jz@renesas.com>; Mark Brown <broonie@kernel.org>; geert
> <geert@linux-m68k.org>
> Cc: linux-spi@vger.kernel.org; linux-renesas-soc@vger.kernel.org; linux-kernel@vger.kernel.org; Felix
> Gu <ustc.gu@gmail.com>
> Subject: [PATCH v2] spi: rzv2h-rspi: Fix SPDR read access width for 16-bit RX
> 
> The RZ/V2H hardware manual (section 7.5.2.2.1) specifies that read access
> size for the SPI Data Register (SPDR) are fixed at 32 bits. The
> RZV2H_RSPI_RX macro for the 16-bit data path used readw(), violating
> this requirement.
> 
> Switch to readl() for the 16-bit RX path to conform to the hardware
> specification.
> 
> Fixes: 8b61c8919dff ("spi: Add driver for the RZ/V2H(P) RSPI IP")
> Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
> Signed-off-by: Felix Gu <ustc.gu@gmail.com>

Reviewed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>

> ---
> Changes in v2:
> - Fix comments from Geert.
> - Link to v1: https://patch.msgid.link/20260605-rzv2h-rspi-v1-1-c1d5ed562249@gmail.com
> 
> To: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> To: Mark Brown <broonie@kernel.org>
> Cc: linux-spi@vger.kernel.org
> Cc: linux-renesas-soc@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> ---
>  drivers/spi/spi-rzv2h-rspi.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/spi/spi-rzv2h-rspi.c b/drivers/spi/spi-rzv2h-rspi.c
> index 1655efda7d20..6ed3fad873b8 100644
> --- a/drivers/spi/spi-rzv2h-rspi.c
> +++ b/drivers/spi/spi-rzv2h-rspi.c
> @@ -135,8 +135,9 @@ static inline void rzv2h_rspi_rx_##type(struct rzv2h_rspi_priv *rspi,	\
>  RZV2H_RSPI_TX(writel, u32)
>  RZV2H_RSPI_TX(writew, u16)
>  RZV2H_RSPI_TX(writeb, u8)
> +/* The read access size for RSPI_SPDR is fixed at 32 bits */
>  RZV2H_RSPI_RX(readl, u32)
> -RZV2H_RSPI_RX(readw, u16)
> +RZV2H_RSPI_RX(readl, u16)
>  RZV2H_RSPI_RX(readl, u8)
> 
>  static void rzv2h_rspi_reg_rmw(const struct rzv2h_rspi_priv *rspi,
> 
> ---
> base-commit: a225caacc36546a09586e3ece36c0313146e7da9
> change-id: 20260605-rzv2h-rspi-3c8dd168fb72
> 
> Best regards,
> --
> Felix Gu <ustc.gu@gmail.com>

Re: [PATCH v2] spi: rzv2h-rspi: Fix SPDR read access width for 16-bit RX

[Mark Brown]

On Wed, 10 Jun 2026 20:08:17 +0800, Felix Gu wrote:
> spi: rzv2h-rspi: Fix SPDR read access width for 16-bit RX

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-7.1

Thanks!

[1/1] spi: rzv2h-rspi: Fix SPDR read access width for 16-bit RX
      https://git.kernel.org/broonie/sound/c/310628484ef0

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark