Re: [PATCH v7 08/10] tpm, tpm_tis: Request threaded interrupt handler

From: Jarkko Sakkinen
Date: Thu Jun 30 2022 - 19:32:33 EST


On Thu, Jun 30, 2022 at 01:26:51AM +0200, Lino Sanfilippo wrote:
> From: Lino Sanfilippo <l.sanfilippo@xxxxxxxxxx>
>
> The TIS interrupt handler at least has to read and write the interrupt
> status register. In case of SPI both operations result in a call to
> tpm_tis_spi_transfer() which uses the bus_lock_mutex of the spi device
> and thus must only be called from a sleepable context.
>
> To ensure this request a threaded interrupt handler.
>
> Signed-off-by: Lino Sanfilippo <l.sanfilippo@xxxxxxxxxx>
> Tested-by: Michael Niew??hner <linux@xxxxxxxxxxxxxx>
> ---
> drivers/char/tpm/tpm_tis_core.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
> index e50a2c78de9f..83b31c25e55c 100644
> --- a/drivers/char/tpm/tpm_tis_core.c
> +++ b/drivers/char/tpm/tpm_tis_core.c
> @@ -802,8 +802,11 @@ static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
> int rc;
> u32 int_status;
>
> - if (devm_request_irq(chip->dev.parent, irq, tis_int_handler, flags,
> - dev_name(&chip->dev), chip) != 0) {
> +
> + rc = devm_request_threaded_irq(chip->dev.parent, irq, NULL,
> + tis_int_handler, IRQF_ONESHOT | flags,
> + dev_name(&chip->dev), chip);
> + if (rc) {
> dev_info(&chip->dev, "Unable to request irq: %d for probe\n",
> irq);
> return -1;
> --
> 2.25.1
>

Reviewed-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx>

BR, Jarkko