[PATCH 02/11] tpm/tpm_i2c_infineon: switch to i2c_lock_segment

From: Peter Rosin
Date: Fri Jun 15 2018 - 06:19:48 EST


Locking the root adapter for __i2c_transfer will deadlock if the
device sits behind a mux-locked I2C mux. Switch to the finer-grained
i2c_lock_segment. If the device does not sit behind a mux-locked mux,
the two locking variants are equivalent.

Signed-off-by: Peter Rosin <peda@xxxxxxxxxx>
---
drivers/char/tpm/tpm_i2c_infineon.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/char/tpm/tpm_i2c_infineon.c b/drivers/char/tpm/tpm_i2c_infineon.c
index 6116cd05e228..b2889405b4fa 100644
--- a/drivers/char/tpm/tpm_i2c_infineon.c
+++ b/drivers/char/tpm/tpm_i2c_infineon.c
@@ -117,7 +117,7 @@ static int iic_tpm_read(u8 addr, u8 *buffer, size_t len)
/* Lock the adapter for the duration of the whole sequence. */
if (!tpm_dev.client->adapter->algo->master_xfer)
return -EOPNOTSUPP;
- i2c_lock_adapter(tpm_dev.client->adapter);
+ i2c_lock_segment(tpm_dev.client->adapter);

if (tpm_dev.chip_type == SLB9645) {
/* use a combined read for newer chips
@@ -192,7 +192,7 @@ static int iic_tpm_read(u8 addr, u8 *buffer, size_t len)
}

out:
- i2c_unlock_adapter(tpm_dev.client->adapter);
+ i2c_unlock_segment(tpm_dev.client->adapter);
/* take care of 'guard time' */
usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI);

@@ -224,7 +224,7 @@ static int iic_tpm_write_generic(u8 addr, u8 *buffer, size_t len,

if (!tpm_dev.client->adapter->algo->master_xfer)
return -EOPNOTSUPP;
- i2c_lock_adapter(tpm_dev.client->adapter);
+ i2c_lock_segment(tpm_dev.client->adapter);

/* prepend the 'register address' to the buffer */
tpm_dev.buf[0] = addr;
@@ -243,7 +243,7 @@ static int iic_tpm_write_generic(u8 addr, u8 *buffer, size_t len,
usleep_range(sleep_low, sleep_hi);
}

- i2c_unlock_adapter(tpm_dev.client->adapter);
+ i2c_unlock_segment(tpm_dev.client->adapter);
/* take care of 'guard time' */
usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI);

--
2.11.0