[PATCH v11 04/14] tpm, tpm_tis: Do not skip reset of original interrupt vector

Lino Sanfilippo
2022-11-24T13:57:11Z

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

If in tpm_tis_probe_irq_single() an error occurs after the original
interrupt vector has been read, restore the interrupts before the error is
returned.

Since the caller does not check the error value, return -1 in any case that
the TPM_CHIP_FLAG_IRQ flag is not set. Since the return value of function
tpm_tis_gen_interrupt() is not longer used, make it a void function.

Fixes: 1107d065fdf1 ("tpm_tis: Introduce intermediate layer for TPM access")
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
---
drivers/char/tpm/tpm_tis_core.c | 29 +++++++++++------------------
1 file changed, 11 insertions(+), 18 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 603b82ca56da..81b9726d3ed2 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -729,7 +729,7 @@ static irqreturn_t tis_int_handler(int dummy, void *dev_id)
return IRQ_HANDLED;
}

-static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
+static void tpm_tis_gen_interrupt(struct tpm_chip *chip)
{
const char *desc = "attempting to generate an interrupt";
u32 cap2;
@@ -738,7 +738,7 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip)

ret = request_locality(chip, 0);
if (ret < 0)
- return ret;
+ return;

if (chip->flags & TPM_CHIP_FLAG_TPM2)
ret = tpm2_get_tpm_pt(chip, 0x100, &cap2, desc);
@@ -746,8 +746,6 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
ret = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc, 0);

release_locality(chip, 0);
-
- return ret;
}

/* Register the IRQ and issue a command that will cause an interrupt. If an
@@ -777,42 +775,37 @@ static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,

rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), irq);
if (rc < 0)
- return rc;
+ goto restore_irqs;

rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &int_status);
if (rc < 0)
- return rc;
+ goto restore_irqs;

/* Clear all existing */
rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), int_status);
if (rc < 0)
- return rc;
-
+ goto restore_irqs;
/* Turn on */
rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality),
intmask | TPM_GLOBAL_INT_ENABLE);
if (rc < 0)
- return rc;
+ goto restore_irqs;

clear_bit(TPM_TIS_IRQ_TESTED, &priv->flags);

/* Generate an interrupt by having the core call through to
* tpm_tis_send
*/
- rc = tpm_tis_gen_interrupt(chip);
- if (rc < 0)
- return rc;
+ tpm_tis_gen_interrupt(chip);

+restore_irqs:
/* tpm_tis_send will either confirm the interrupt is working or it
* will call disable_irq which undoes all of the above.
*/
if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) {
- rc = tpm_tis_write8(priv, original_int_vec,
- TPM_INT_VECTOR(priv->locality));
- if (rc < 0)
- return rc;
-
- return 1;
+ tpm_tis_write8(priv, original_int_vec,
+ TPM_INT_VECTOR(priv->locality));
+ return -1;
}

return 0;
--
2.36.1