Commit c663b269 authored by Armin Wolf's avatar Armin Wolf Committed by Hans de Goede
Browse files

platform/x86: wmi: Support reading/writing 16 bit EC values 



The ACPI EC address space handler currently only supports
reading/writing 8 bit values. Some firmware implementations however
want to access for example 16 bit values, which is perfectly legal
according to the ACPI spec.

Add support for reading/writing such values.

Tested on a Dell Inspiron 3505 and a Asus Prime B650-Plus.

Reviewed-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: default avatarArmin Wolf <W_Armin@gmx.de>
Reviewed-by: default avatarKuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Link: https://lore.kernel.org/r/20240314184538.2933-1-W_Armin@gmx.de


Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
parent 0cd33df4

drivers/platform/x86/wmi.c

+41 −13
Original line number Diff line number Diff line
@@ -1153,6 +1153,34 @@ static int parse_wdg(struct device *wmi_bus_dev, struct platform_device *pdev) 
	return 0;

}



static int ec_read_multiple(u8 address, u8 *buffer, size_t bytes)

{

	size_t i;

	int ret;



	for (i = 0; i < bytes; i++) {

		ret = ec_read(address + i, &buffer[i]);

		if (ret < 0)

			return ret;

	}



	return 0;

}



static int ec_write_multiple(u8 address, u8 *buffer, size_t bytes)

{

	size_t i;

	int ret;



	for (i = 0; i < bytes; i++) {

		ret = ec_write(address + i, buffer[i]);

		if (ret < 0)

			return ret;

	}



	return 0;

}



/*

 * WMI can have EmbeddedControl access regions. In which case, we just want to

 * hand these off to the EC driver.
@@ -1162,27 +1190,27 @@ acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address, 
			  u32 bits, u64 *value,

			  void *handler_context, void *region_context)

{

	int result = 0;

	u8 temp = 0;

	int bytes = bits / BITS_PER_BYTE;

	int ret;



	if ((address > 0xFF) || !value)

	if (!value)

		return AE_NULL_ENTRY;



	if (!bytes || bytes > sizeof(*value))

		return AE_BAD_PARAMETER;



	if (function != ACPI_READ && function != ACPI_WRITE)

	if (address > U8_MAX || address + bytes - 1 > U8_MAX)

		return AE_BAD_PARAMETER;



	if (bits != 8)

	if (function != ACPI_READ && function != ACPI_WRITE)

		return AE_BAD_PARAMETER;



	if (function == ACPI_READ) {

		result = ec_read(address, &temp);

		*value = temp;

	} else {

		temp = 0xff & *value;

		result = ec_write(address, temp);

	}

	if (function == ACPI_READ)

		ret = ec_read_multiple(address, (u8 *)value, bytes);

	else

		ret = ec_write_multiple(address, (u8 *)value, bytes);



	switch (result) {

	switch (ret) {

	case -EINVAL:

		return AE_BAD_PARAMETER;

	case -ENODEV: