RE: [PATCH v2 3/3] spi: fsl-qspi: Use reinit_completion() for repeated operations

[Bough Chen]

> -----Original Message-----
> From: Felix Gu <ustc.gu@xxxxxxxxx>
> Sent: 2026年3月4日 20:47
> To: Han Xu <han.xu@xxxxxxx>; Bough Chen <haibo.chen@xxxxxxx>; Mark
> Brown <broonie@xxxxxxxxxx>; Frank Li <frank.li@xxxxxxx>; Yogesh Gaur
> <yogeshgaur.83@xxxxxxxxx>; Yogesh Narayan Gaur
> <yogeshnarayan.gaur@xxxxxxx>; Boris Brezillon <bbrezillon@xxxxxxxxxx>;
> Frieder Schrempf <frieder.schrempf@xxxxxxxxxx>
> Cc: linux-spi@xxxxxxxxxxxxxxx; imx@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> Felix Gu <ustc.gu@xxxxxxxxx>
> Subject: [PATCH v2 3/3] spi: fsl-qspi: Use reinit_completion() for repeated
> operations
> 
> The driver currently calls init_completion() during every spi_mem_op.
> Tchnically it may work, but it's not the recommended pattern.
> 
> According to the kernel documentation: Calling init_completion() on the same
> completion object twice is most likely a bug as it re-initializes the queue to an
> empty queue and enqueued tasks could get "lost" - use reinit_completion() in
> that case, but be aware of other races.
> 
> So moves the initial initialization to probe function and uses
> reinit_completion() for subsequent operations.

Reviewed-by: Haibo Chen <haibo.chen@xxxxxxx>

Regards
Haibo Chen
>
> 
> Fixes: 84d043185dbe ("spi: Add a driver for the Freescale/NXP QuadSPI
> controller")
> Signed-off-by: Felix Gu <ustc.gu@xxxxxxxxx>
> ---
>  drivers/spi/spi-fsl-qspi.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/spi/spi-fsl-qspi.c b/drivers/spi/spi-fsl-qspi.c index
> a223b4bc6e63..57358851029b 100644
> --- a/drivers/spi/spi-fsl-qspi.c
> +++ b/drivers/spi/spi-fsl-qspi.c
> @@ -633,7 +633,7 @@ static int fsl_qspi_do_op(struct fsl_qspi *q, const struct
> spi_mem_op *op)
>  	void __iomem *base = q->iobase;
>  	int err = 0;
> 
> -	init_completion(&q->c);
> +	reinit_completion(&q->c);
> 
>  	/*
>  	 * Always start the sequence at the same index since we update @@
> -965,6 +965,7 @@ static int fsl_qspi_probe(struct platform_device *pdev)
>  	if (ret < 0)
>  		return ret;
> 
> +	init_completion(&q->c);
>  	ret = devm_request_irq(dev, ret,
>  			fsl_qspi_irq_handler, 0, pdev->name, q);
>  	if (ret) {
> 
> --
> 2.43.0