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[3/4] i2c: i801: Improve i801_block_transaction_byte_by_byte

Message ID 6686b692-0caf-734e-18cd-7879810b29cd@gmail.com
State New
Headers show
Series i2c: i801: next set of improvements | expand

Commit Message

Heiner Kallweit March 4, 2023, 9:36 p.m. UTC 
Here we don't have to write SMBHSTCNT in each iteration of the loop.
Bit SMBHSTCNT_START is internally cleared immediately, therefore
we don't have to touch the value of SMBHSTCNT until the last byte.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/i2c/busses/i2c-i801.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 7641bd0ac..e1350a8cc 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -677,11 +677,11 @@  static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
 	for (i = 1; i <= len; i++) {
 		if (i == len && read_write == I2C_SMBUS_READ)
 			smbcmd |= SMBHSTCNT_LAST_BYTE;
-		outb_p(smbcmd, SMBHSTCNT(priv));
 
 		if (i == 1)
-			outb_p(inb(SMBHSTCNT(priv)) | SMBHSTCNT_START,
-			       SMBHSTCNT(priv));
+			outb_p(smbcmd | SMBHSTCNT_START, SMBHSTCNT(priv));
+		else if (smbcmd & SMBHSTCNT_LAST_BYTE)
+			outb_p(smbcmd, SMBHSTCNT(priv));
 
 		status = i801_wait_byte_done(priv);
 		if (status)