On Thu, Feb 16, 2017 at 04:08:22PM +0000, Peter Huewe wrote: > The algorithm for sending data to the TPM is mostly identical to the > algorithm for receiving data from the TPM, so a single function is > sufficient to handle both cases. > > This is a prequisite for all the other fixes, so we don't have to fix > everything twice (send/receive) > > Cc: <[email protected]> > [prerequisite for other fixes in this series] > Fixes: 0edbfea537d1 ("tpm/tpm_tis_spi: Add support for spi phy") > Signed-off-by: Alexander Steffen <[email protected]> > Signed-off-by: Peter Huewe <[email protected]>
Reviewed-by: Jarkko Sakkinen <[email protected]> /Jarkko > --- > drivers/char/tpm/tpm_tis_spi.c | 87 > ++++++++++++------------------------------ > 1 file changed, 24 insertions(+), 63 deletions(-) > > diff --git a/drivers/char/tpm/tpm_tis_spi.c b/drivers/char/tpm/tpm_tis_spi.c > index 5292e5768a7e..6e1a3c43f621 100644 > --- a/drivers/char/tpm/tpm_tis_spi.c > +++ b/drivers/char/tpm/tpm_tis_spi.c > @@ -47,8 +47,8 @@ struct tpm_tis_spi_phy { > struct tpm_tis_data priv; > struct spi_device *spi_device; > > - u8 tx_buf[MAX_SPI_FRAMESIZE + 4]; > - u8 rx_buf[MAX_SPI_FRAMESIZE + 4]; > + u8 tx_buf[4]; > + u8 rx_buf[4]; > }; > > static inline struct tpm_tis_spi_phy *to_tpm_tis_spi_phy(struct tpm_tis_data > *data) > @@ -56,8 +56,8 @@ static inline struct tpm_tis_spi_phy > *to_tpm_tis_spi_phy(struct tpm_tis_data *da > return container_of(data, struct tpm_tis_spi_phy, priv); > } > > -static int tpm_tis_spi_read_bytes(struct tpm_tis_data *data, u32 addr, > - u16 len, u8 *result) > +static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u8 len, > + u8 *buffer, u8 direction) > { > struct tpm_tis_spi_phy *phy = to_tpm_tis_spi_phy(data); > int ret, i; > @@ -66,17 +66,17 @@ static int tpm_tis_spi_read_bytes(struct tpm_tis_data > *data, u32 addr, > .tx_buf = phy->tx_buf, > .rx_buf = phy->rx_buf, > .len = 4, > + .cs_change = 1, > }; > > if (len > MAX_SPI_FRAMESIZE) > return -ENOMEM; > > - phy->tx_buf[0] = 0x80 | (len - 1); > + phy->tx_buf[0] = direction | (len - 1); > phy->tx_buf[1] = 0xd4; > - phy->tx_buf[2] = (addr >> 8) & 0xFF; > - phy->tx_buf[3] = addr & 0xFF; > + phy->tx_buf[2] = addr >> 8; > + phy->tx_buf[3] = addr; > > - spi_xfer.cs_change = 1; > spi_message_init(&m); > spi_message_add_tail(&spi_xfer, &m); > > @@ -85,7 +85,7 @@ static int tpm_tis_spi_read_bytes(struct tpm_tis_data > *data, u32 addr, > if (ret < 0) > goto exit; > > - memset(phy->tx_buf, 0, len); > + phy->tx_buf[0] = 0; > > /* According to TCG PTP specification, if there is no TPM present at > * all, then the design has a weak pull-up on MISO. If a TPM is not > @@ -103,7 +103,14 @@ static int tpm_tis_spi_read_bytes(struct tpm_tis_data > *data, u32 addr, > > spi_xfer.cs_change = 0; > spi_xfer.len = len; > - spi_xfer.rx_buf = result; > + > + if (direction) { > + spi_xfer.tx_buf = NULL; > + spi_xfer.rx_buf = buffer; > + } else { > + spi_xfer.tx_buf = buffer; > + spi_xfer.rx_buf = NULL; > + } > > spi_message_init(&m); > spi_message_add_tail(&spi_xfer, &m); > @@ -114,62 +121,16 @@ static int tpm_tis_spi_read_bytes(struct tpm_tis_data > *data, u32 addr, > return ret; > } > > +static int tpm_tis_spi_read_bytes(struct tpm_tis_data *data, u32 addr, > + u16 len, u8 *result) > +{ > + return tpm_tis_spi_transfer(data, addr, len, result, 0x80); > +} > + > static int tpm_tis_spi_write_bytes(struct tpm_tis_data *data, u32 addr, > u16 len, u8 *value) > { > - struct tpm_tis_spi_phy *phy = to_tpm_tis_spi_phy(data); > - int ret, i; > - struct spi_message m; > - struct spi_transfer spi_xfer = { > - .tx_buf = phy->tx_buf, > - .rx_buf = phy->rx_buf, > - .len = 4, > - }; > - > - if (len > MAX_SPI_FRAMESIZE) > - return -ENOMEM; > - > - phy->tx_buf[0] = len - 1; > - phy->tx_buf[1] = 0xd4; > - phy->tx_buf[2] = (addr >> 8) & 0xFF; > - phy->tx_buf[3] = addr & 0xFF; > - > - spi_xfer.cs_change = 1; > - spi_message_init(&m); > - spi_message_add_tail(&spi_xfer, &m); > - > - spi_bus_lock(phy->spi_device->master); > - ret = spi_sync_locked(phy->spi_device, &m); > - if (ret < 0) > - goto exit; > - > - memset(phy->tx_buf, 0, len); > - > - /* According to TCG PTP specification, if there is no TPM present at > - * all, then the design has a weak pull-up on MISO. If a TPM is not > - * present, a pull-up on MISO means that the SB controller sees a 1, > - * and will latch in 0xFF on the read. > - */ > - for (i = 0; (phy->rx_buf[0] & 0x01) == 0 && i < TPM_RETRY; i++) { > - spi_xfer.len = 1; > - spi_message_init(&m); > - spi_message_add_tail(&spi_xfer, &m); > - ret = spi_sync_locked(phy->spi_device, &m); > - if (ret < 0) > - goto exit; > - } > - > - spi_xfer.len = len; > - spi_xfer.tx_buf = value; > - spi_xfer.cs_change = 0; > - spi_xfer.tx_buf = value; > - spi_message_init(&m); > - spi_message_add_tail(&spi_xfer, &m); > - ret = spi_sync_locked(phy->spi_device, &m); > - > -exit: > - spi_bus_unlock(phy->spi_device->master); > - return ret; > + return tpm_tis_spi_transfer(data, addr, len, value, 0); > } > > static int tpm_tis_spi_read16(struct tpm_tis_data *data, u32 addr, u16 > *result) > -- > 2.7.4 > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ tpmdd-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/tpmdd-devel
