[PATCH v9 09/12] tpm, tpm_tis: Request threaded interrupt handler

From: Lino Sanfilippo
Date: Thu Nov 10 2022 - 10:27:27 EST


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 Niewöhner <linux@xxxxxxxxxxxxxx>
Reviewed-by: Jarkko Sakkinen <jarkko@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 ecde684a8f80..ced8eae3e4d5 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -813,8 +813,11 @@ 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