[PATCH v8 1/8] tpm: tpm_tis: Make implementation of read16, read32 and write32 optional

amirmizi6
2020-05-12T14:15:49Z

Only tpm_tis can use memory-mapped I/O, which is truly mapped into
the kernel's memory space. Therefore, using ioread16/ioread32/iowrite32
turns into a straightforward pointer dereference.
Every other driver requires more complicated operations to read more than
one byte at a time and will just fall back to read_bytes/write_bytes.
Therefore, move this common code out of tpm_tis_spi and into tpm_tis_core
so that it is used automatically when low-level drivers do not implement
the specialized methods.

Co-developed-by: Alexander Steffen <Alexander.Steffen@infineon.com>
Signed-off-by: Alexander Steffen <Alexander.Steffen@infineon.com>
Signed-off-by: Amir Mizinski <amirmizi6@gmail.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
---
drivers/char/tpm/tpm_tis_core.h | 38 +++++++++++++++++++++++++++++++---
drivers/char/tpm/tpm_tis_spi_main.c | 41 -------------------------------------
2 files changed, 35 insertions(+), 44 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h
index 7337819..d06c65b 100644
--- a/drivers/char/tpm/tpm_tis_core.h
+++ b/drivers/char/tpm/tpm_tis_core.h
@@ -122,13 +122,35 @@ static inline int tpm_tis_read8(struct tpm_tis_data *data, u32 addr, u8 *result)
static inline int tpm_tis_read16(struct tpm_tis_data *data, u32 addr,
u16 *result)
{
- return data->phy_ops->read16(data, addr, result);
+ __le16 result_le;
+ int rc;
+
+ if (data->phy_ops->read16)
+ return data->phy_ops->read16(data, addr, result);
+
+ rc = data->phy_ops->read_bytes(data, addr, sizeof(u16),
+ (u8 *)&result_le);
+ if (!rc)
+ *result = le16_to_cpu(result_le);
+
+ return rc;
}

static inline int tpm_tis_read32(struct tpm_tis_data *data, u32 addr,
u32 *result)
{
- return data->phy_ops->read32(data, addr, result);
+ __le32 result_le;
+ int rc;
+
+ if (data->phy_ops->read32)
+ return data->phy_ops->read32(data, addr, result);
+
+ rc = data->phy_ops->read_bytes(data, addr, sizeof(u32),
+ (u8 *)&result_le);
+ if (!rc)
+ *result = le32_to_cpu(result_le);
+
+ return rc;
}

static inline int tpm_tis_write_bytes(struct tpm_tis_data *data, u32 addr,
@@ -145,7 +167,17 @@ static inline int tpm_tis_write8(struct tpm_tis_data *data, u32 addr, u8 value)
static inline int tpm_tis_write32(struct tpm_tis_data *data, u32 addr,
u32 value)
{
- return data->phy_ops->write32(data, addr, value);
+ __le32 value_le;
+ int rc;
+
+ if (data->phy_ops->write32)
+ return data->phy_ops->write32(data, addr, value);
+
+ value_le = cpu_to_le32(value);
+ rc = data->phy_ops->write_bytes(data, addr, sizeof(u32),
+ (u8 *)&value_le);
+
+ return rc;
}

static inline bool is_bsw(void)
diff --git a/drivers/char/tpm/tpm_tis_spi_main.c b/drivers/char/tpm/tpm_tis_spi_main.c
index d1754fd..95fef9d 100644
--- a/drivers/char/tpm/tpm_tis_spi_main.c
+++ b/drivers/char/tpm/tpm_tis_spi_main.c
@@ -152,44 +152,6 @@ static int tpm_tis_spi_write_bytes(struct tpm_tis_data *data, u32 addr,
return tpm_tis_spi_transfer(data, addr, len, NULL, value);
}

-int tpm_tis_spi_read16(struct tpm_tis_data *data, u32 addr, u16 *result)
-{
- __le16 result_le;
- int rc;
-
- rc = data->phy_ops->read_bytes(data, addr, sizeof(u16),
- (u8 *)&result_le);
- if (!rc)
- *result = le16_to_cpu(result_le);
-
- return rc;
-}
-
-int tpm_tis_spi_read32(struct tpm_tis_data *data, u32 addr, u32 *result)
-{
- __le32 result_le;
- int rc;
-
- rc = data->phy_ops->read_bytes(data, addr, sizeof(u32),
- (u8 *)&result_le);
- if (!rc)
- *result = le32_to_cpu(result_le);
-
- return rc;
-}
-
-int tpm_tis_spi_write32(struct tpm_tis_data *data, u32 addr, u32 value)
-{
- __le32 value_le;
- int rc;
-
- value_le = cpu_to_le32(value);
- rc = data->phy_ops->write_bytes(data, addr, sizeof(u32),
- (u8 *)&value_le);
-
- return rc;
-}
-
int tpm_tis_spi_init(struct spi_device *spi, struct tpm_tis_spi_phy *phy,
int irq, const struct tpm_tis_phy_ops *phy_ops)
{
@@ -205,9 +167,6 @@ int tpm_tis_spi_init(struct spi_device *spi, struct tpm_tis_spi_phy *phy,
static const struct tpm_tis_phy_ops tpm_spi_phy_ops = {
.read_bytes = tpm_tis_spi_read_bytes,
.write_bytes = tpm_tis_spi_write_bytes,
- .read16 = tpm_tis_spi_read16,
- .read32 = tpm_tis_spi_read32,
- .write32 = tpm_tis_spi_write32,
};

static int tpm_tis_spi_probe(struct spi_device *dev)
--
2.7.4