On Fri, Jun 10, 2022 at 01:08:44PM +0200, LinoSanfilippo@xxxxxx 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.
>
> Fixes: 1a339b658d9d ("tpm_tis_spi: Pass the SPI IRQ down to the driver")
> Signed-off-by: Lino Sanfilippo <l.sanfilippo@xxxxxxxxxx>
> ---
> 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 0ef74979bc2c..8b5aa4fdbe92 100644
> --- a/drivers/char/tpm/tpm_tis_core.c
> +++ b/drivers/char/tpm/tpm_tis_core.c
> @@ -794,8 +794,11 @@ 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;
> --
> 2.36.1
>
I actually would not add fixes tag to this because given that
interrupt support is quite unusable, this should not cause any
harm.
The code change itself is fine.
BR, Jarkko
