Commit 63fd342f authored by Heiner Kallweit's avatar Heiner Kallweit Committed by Wolfram Sang
Browse files

i2c: i801: Handle SMBAUXCTL_E32B in i801_block_transaction_by_block only 



Currently we touch SMBAUXCTL even if not needed. That's the case for block
commands that don't use block buffer mode, either because block buffer
mode isn't available or because it's not supported for the respective
command (e.g. I2C block transfer). Improve this by setting/resetting
SMBAUXCTL_E32B in i801_block_transaction_by_block() only.

Small downside is that we now access SMBAUXCTL twice for transactions
that use PEC and block buffer mode. But this should a rather rare case
and the impact is negligible.

Signed-off-by: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: default avatarJean Delvare <jdelvare@suse.de>
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
parent dd2d18b5

drivers/i2c/busses/i2c-i801.c

+12 −9
Original line number Diff line number Diff line
@@ -511,19 +511,23 @@ static int i801_block_transaction_by_block(struct i801_priv *priv, 


	status = i801_transaction(priv, xact);

	if (status)

		return status;

		goto out;



	if (read_write == I2C_SMBUS_READ ||

	    command == I2C_SMBUS_BLOCK_PROC_CALL) {

		len = inb_p(SMBHSTDAT0(priv));

		if (len < 1 || len > I2C_SMBUS_BLOCK_MAX)

			return -EPROTO;

		if (len < 1 || len > I2C_SMBUS_BLOCK_MAX) {

			status = -EPROTO;

			goto out;

		}



		data->block[0] = len;

		for (i = 0; i < len; i++)

			data->block[i + 1] = inb_p(SMBBLKDAT(priv));

	}

	return 0;

out:

	outb_p(inb_p(SMBAUXCTL(priv)) & ~SMBAUXCTL_E32B, SMBAUXCTL(priv));

	return status;

}



static void i801_isr_byte_done(struct i801_priv *priv)
@@ -921,11 +925,10 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr, 
		ret = i801_simple_transaction(priv, data, read_write, size);



	/* Some BIOSes don't like it when PEC is enabled at reboot or resume

	   time, so we forcibly disable it after every transaction. Turn off

	   E32B for the same reason. */

	if (hwpec || block)

		outb_p(inb_p(SMBAUXCTL(priv)) &

		       ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B), SMBAUXCTL(priv));

	 * time, so we forcibly disable it after every transaction.

	 */

	if (hwpec)

		outb_p(inb_p(SMBAUXCTL(priv)) & ~SMBAUXCTL_CRC, SMBAUXCTL(priv));

out:

	/*

	 * Unlock the SMBus device for use by BIOS/ACPI,