| Message ID | 20170522091638.8436-1-enric.balletbo@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, May 22, 2017 at 11:16:38AM +0200, Enric Balletbo i Serra wrote: > From: Bryan Freed <bfreed@chromium.org> > > When the I2C Infineon part is attached to an I2C adapter that imposes > a size limitation, large requests will fail with -EOPNOTSUPP. Retry > them with a sane minimum size without re-issuing the 0x05 command > as this appears to occasionally put the TPM in a bad state. > > Signed-off-by: Bryan Freed <bfreed@chromium.org> > [rework the patch to adapt to the feedback received] > Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> > Acked-by: Andrew Lunn <andrew@lunn.ch> > Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> > Reviewed-by: Andrew Lunn <andrew@lunn.ch> > --- > The purpose of this resend is only a reminder for if this can be accepted > for the next merge window as I missed last merge. Thanks. I'm sorry about this. Yes it can. /Jarkko > > drivers/char/tpm/tpm_i2c_infineon.c | 76 +++++++++++++++++++++++++++---------- > 1 file changed, 56 insertions(+), 20 deletions(-) > > diff --git a/drivers/char/tpm/tpm_i2c_infineon.c b/drivers/char/tpm/tpm_i2c_infineon.c > index dc47fa2..79d6bbb 100644 > --- a/drivers/char/tpm/tpm_i2c_infineon.c > +++ b/drivers/char/tpm/tpm_i2c_infineon.c > @@ -70,6 +70,7 @@ struct tpm_inf_dev { > u8 buf[TPM_BUFSIZE + sizeof(u8)]; /* max. buffer size + addr */ > struct tpm_chip *chip; > enum i2c_chip_type chip_type; > + unsigned int adapterlimit; > }; > > static struct tpm_inf_dev tpm_dev; > @@ -111,6 +112,7 @@ static int iic_tpm_read(u8 addr, u8 *buffer, size_t len) > > int rc = 0; > int count; > + unsigned int msglen = len; > > /* Lock the adapter for the duration of the whole sequence. */ > if (!tpm_dev.client->adapter->algo->master_xfer) > @@ -131,27 +133,61 @@ static int iic_tpm_read(u8 addr, u8 *buffer, size_t len) > usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI); > } > } else { > - /* slb9635 protocol should work in all cases */ > - for (count = 0; count < MAX_COUNT; count++) { > - rc = __i2c_transfer(tpm_dev.client->adapter, &msg1, 1); > - if (rc > 0) > - break; /* break here to skip sleep */ > - > - usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI); > - } > - > - if (rc <= 0) > - goto out; > - > - /* After the TPM has successfully received the register address > - * it needs some time, thus we're sleeping here again, before > - * retrieving the data > + /* Expect to send one command message and one data message, but > + * support looping over each or both if necessary. > */ > - for (count = 0; count < MAX_COUNT; count++) { > - usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI); > - rc = __i2c_transfer(tpm_dev.client->adapter, &msg2, 1); > - if (rc > 0) > - break; > + while (len > 0) { > + /* slb9635 protocol should work in all cases */ > + for (count = 0; count < MAX_COUNT; count++) { > + rc = __i2c_transfer(tpm_dev.client->adapter, > + &msg1, 1); > + if (rc > 0) > + break; /* break here to skip sleep */ > + > + usleep_range(SLEEP_DURATION_LOW, > + SLEEP_DURATION_HI); > + } > + > + if (rc <= 0) > + goto out; > + > + /* After the TPM has successfully received the register > + * address it needs some time, thus we're sleeping here > + * again, before retrieving the data > + */ > + for (count = 0; count < MAX_COUNT; count++) { > + if (tpm_dev.adapterlimit) { > + msglen = min_t(unsigned int, > + tpm_dev.adapterlimit, > + len); > + msg2.len = msglen; > + } > + usleep_range(SLEEP_DURATION_LOW, > + SLEEP_DURATION_HI); > + rc = __i2c_transfer(tpm_dev.client->adapter, > + &msg2, 1); > + if (rc > 0) { > + /* Since len is unsigned, make doubly > + * sure we do not underflow it. > + */ > + if (msglen > len) > + len = 0; > + else > + len -= msglen; > + msg2.buf += msglen; > + break; > + } > + /* If the I2C adapter rejected the request (e.g > + * when the quirk read_max_len < len) fall back > + * to a sane minimum value and try again. > + */ > + if (rc == -EOPNOTSUPP) > + tpm_dev.adapterlimit = > + I2C_SMBUS_BLOCK_MAX; > + } > + > + if (rc <= 0) > + goto out; > } > } > > -- > 2.9.3 > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
diff --git a/drivers/char/tpm/tpm_i2c_infineon.c b/drivers/char/tpm/tpm_i2c_infineon.c index dc47fa2..79d6bbb 100644 --- a/drivers/char/tpm/tpm_i2c_infineon.c +++ b/drivers/char/tpm/tpm_i2c_infineon.c @@ -70,6 +70,7 @@ struct tpm_inf_dev { u8 buf[TPM_BUFSIZE + sizeof(u8)]; /* max. buffer size + addr */ struct tpm_chip *chip; enum i2c_chip_type chip_type; + unsigned int adapterlimit; }; static struct tpm_inf_dev tpm_dev; @@ -111,6 +112,7 @@ static int iic_tpm_read(u8 addr, u8 *buffer, size_t len) int rc = 0; int count; + unsigned int msglen = len; /* Lock the adapter for the duration of the whole sequence. */ if (!tpm_dev.client->adapter->algo->master_xfer) @@ -131,27 +133,61 @@ static int iic_tpm_read(u8 addr, u8 *buffer, size_t len) usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI); } } else { - /* slb9635 protocol should work in all cases */ - for (count = 0; count < MAX_COUNT; count++) { - rc = __i2c_transfer(tpm_dev.client->adapter, &msg1, 1); - if (rc > 0) - break; /* break here to skip sleep */ - - usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI); - } - - if (rc <= 0) - goto out; - - /* After the TPM has successfully received the register address - * it needs some time, thus we're sleeping here again, before - * retrieving the data + /* Expect to send one command message and one data message, but + * support looping over each or both if necessary. */ - for (count = 0; count < MAX_COUNT; count++) { - usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI); - rc = __i2c_transfer(tpm_dev.client->adapter, &msg2, 1); - if (rc > 0) - break; + while (len > 0) { + /* slb9635 protocol should work in all cases */ + for (count = 0; count < MAX_COUNT; count++) { + rc = __i2c_transfer(tpm_dev.client->adapter, + &msg1, 1); + if (rc > 0) + break; /* break here to skip sleep */ + + usleep_range(SLEEP_DURATION_LOW, + SLEEP_DURATION_HI); + } + + if (rc <= 0) + goto out; + + /* After the TPM has successfully received the register + * address it needs some time, thus we're sleeping here + * again, before retrieving the data + */ + for (count = 0; count < MAX_COUNT; count++) { + if (tpm_dev.adapterlimit) { + msglen = min_t(unsigned int, + tpm_dev.adapterlimit, + len); + msg2.len = msglen; + } + usleep_range(SLEEP_DURATION_LOW, + SLEEP_DURATION_HI); + rc = __i2c_transfer(tpm_dev.client->adapter, + &msg2, 1); + if (rc > 0) { + /* Since len is unsigned, make doubly + * sure we do not underflow it. + */ + if (msglen > len) + len = 0; + else + len -= msglen; + msg2.buf += msglen; + break; + } + /* If the I2C adapter rejected the request (e.g + * when the quirk read_max_len < len) fall back + * to a sane minimum value and try again. + */ + if (rc == -EOPNOTSUPP) + tpm_dev.adapterlimit = + I2C_SMBUS_BLOCK_MAX; + } + + if (rc <= 0) + goto out; } }