2024-03-04 16:16:49

by Gustavo A. R. Silva

[permalink] [raw]
Subject: Re: [PATCH v2 2/3] spi: axi-spi-engine: use __counted_by() attribute



On 04/03/24 10:04, David Lechner wrote:
> This adds the __counted_by() attribute to the flex array at the end of
> struct spi_engine_program in the AXI SPI Engine controller driver.
>
> The assignment of the length field has to be reordered to be before
> the access to the flex array in order to avoid potential compiler
> warnings/errors due to adding the __counted_by() attribute.
>
> Suggested-by: Nuno Sá <[email protected]>
> Signed-off-by: David Lechner <[email protected]>

Reviewed-by: Gustavo A. R. Silva <[email protected]>

Thanks
--
Gustavo

> ---
> v2 changes:
> * Reordered assignment of length field.
> ---
> drivers/spi/spi-axi-spi-engine.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/spi/spi-axi-spi-engine.c b/drivers/spi/spi-axi-spi-engine.c
> index d89f75170c9e..a8f626165f44 100644
> --- a/drivers/spi/spi-axi-spi-engine.c
> +++ b/drivers/spi/spi-axi-spi-engine.c
> @@ -75,7 +75,7 @@
>
> struct spi_engine_program {
> unsigned int length;
> - uint16_t instructions[];
> + uint16_t instructions[] __counted_by(length);
> };
>
> /**
> @@ -115,9 +115,10 @@ struct spi_engine {
> static void spi_engine_program_add_cmd(struct spi_engine_program *p,
> bool dry, uint16_t cmd)
> {
> - if (!dry)
> - p->instructions[p->length] = cmd;
> p->length++;
> +
> + if (!dry)
> + p->instructions[p->length - 1] = cmd;
> }
>
> static unsigned int spi_engine_get_config(struct spi_device *spi)
>