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

[amirmizi6]

From: Amir Mizinski <amirmizi6@xxxxxxxxx>

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@xxxxxxxxxxxx>
Signed-off-by: Alexander Steffen <Alexander.Steffen@xxxxxxxxxxxx>
Signed-off-by: Amir Mizinski <amirmizi6@xxxxxxxxx>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
---
 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