Commit 0a30446c authored Aug 12, 2018 by Hans de Goede Committed by Wolfram Sang Aug 20, 2018

i2c: core: ACPI: Make acpi_gsb_i2c_read_bytes() check i2c_transfer return value



Currently acpi_gsb_i2c_read_bytes() directly returns i2c_transfer's return
value. i2c_transfer returns a value < 0 on error and 2 (for 2 successfully
executed transfers) on success. But the ACPI code expects 0 on success, so
currently acpi_gsb_i2c_read_bytes()'s caller does:

        if (status > 0)
                status = 0;

This commit makes acpi_gsb_i2c_read_bytes() return a value which can be
directly consumed by the ACPI code, mirroring acpi_gsb_i2c_write_bytes(),
this commit also makes acpi_gsb_i2c_read_bytes() explitcly check that
i2c_transfer returns 2, rather then accepting any value > 0.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

parent c463a158

drivers/i2c/i2c-core-acpi.c

+5 −3

Original line number	Diff line number	Diff line
		@@ -453,8 +453,12 @@ static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
		else
		dev_err(&client->adapter->dev, "i2c read %d bytes from client@%#x starting at reg %#x failed, error: %d\n",
		data_len, client->addr, cmd, ret);
		} else {
		/* 2 transfers must have completed successfully */
		} else if (ret == 2) {
		memcpy(data, buffer, data_len);
		ret = 0;
		} else {
		ret = -EIO;
		}

		kfree(buffer);
		@@ -595,8 +599,6 @@ i2c_acpi_space_handler(u32 function, acpi_physical_address command,
		if (action == ACPI_READ) {
		status = acpi_gsb_i2c_read_bytes(client, command,
		gsb->data, info->access_length);
		if (status > 0)
		status = 0;
		} else {
		status = acpi_gsb_i2c_write_bytes(client, command,
		gsb->data, info->access_length);