linux/sound/hda/intel-sdw-acpi.c
Peter Ujfalusi 485ddd519f ALSA: hda: intel-sdw-acpi: Use u8 type for link index
Use consistently u8 for sdw link index. The id is limited to 4, u8 is
adequate in size to store it.

This change will also fixes the following compiler warning/error (W=1):

sound/hda/intel-sdw-acpi.c: In function ‘sdw_intel_acpi_scan’:
sound/hda/intel-sdw-acpi.c:34:35: error: ‘-subproperties’ directive output may be truncated writing 14 bytes into a region of size between 7 and 17 [-Werror=format-truncation=]
   34 |                  "mipi-sdw-link-%d-subproperties", i);
      |                                   ^~~~~~~~~~~~~~
In function ‘is_link_enabled’,
    inlined from ‘sdw_intel_scan_controller’ at sound/hda/intel-sdw-acpi.c:106:8,
    inlined from ‘sdw_intel_acpi_scan’ at sound/hda/intel-sdw-acpi.c:180:9:
sound/hda/intel-sdw-acpi.c:33:9: note: ‘snprintf’ output between 30 and 40 bytes into a destination of size 32
   33 |         snprintf(name, sizeof(name),
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
   34 |                  "mipi-sdw-link-%d-subproperties", i);
      |                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors

The warnings got brought to light by a recent patch upstream:
commit 6d4ab2e97d ("extrawarn: enable format and stringop overflow warnings in W=1")

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20230912162617.29178-1-peter.ujfalusi@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-09-13 09:43:10 +02:00

186 lines
4.7 KiB
C

// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
// Copyright(c) 2015-2021 Intel Corporation.
/*
* SDW Intel ACPI scan helpers
*/
#include <linux/acpi.h>
#include <linux/bits.h>
#include <linux/bitfield.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/export.h>
#include <linux/fwnode.h>
#include <linux/module.h>
#include <linux/soundwire/sdw_intel.h>
#include <linux/string.h>
#define SDW_LINK_TYPE 4 /* from Intel ACPI documentation */
#define SDW_MAX_LINKS 4
static int ctrl_link_mask;
module_param_named(sdw_link_mask, ctrl_link_mask, int, 0444);
MODULE_PARM_DESC(sdw_link_mask, "Intel link mask (one bit per link)");
static bool is_link_enabled(struct fwnode_handle *fw_node, u8 idx)
{
struct fwnode_handle *link;
char name[32];
u32 quirk_mask = 0;
/* Find master handle */
snprintf(name, sizeof(name),
"mipi-sdw-link-%hhu-subproperties", idx);
link = fwnode_get_named_child_node(fw_node, name);
if (!link)
return false;
fwnode_property_read_u32(link,
"intel-quirk-mask",
&quirk_mask);
if (quirk_mask & SDW_INTEL_QUIRK_MASK_BUS_DISABLE)
return false;
return true;
}
static int
sdw_intel_scan_controller(struct sdw_intel_acpi_info *info)
{
struct acpi_device *adev = acpi_fetch_acpi_dev(info->handle);
u8 count, i;
int ret;
if (!adev)
return -EINVAL;
/* Found controller, find links supported */
count = 0;
ret = fwnode_property_read_u8_array(acpi_fwnode_handle(adev),
"mipi-sdw-master-count", &count, 1);
/*
* In theory we could check the number of links supported in
* hardware, but in that step we cannot assume SoundWire IP is
* powered.
*
* In addition, if the BIOS doesn't even provide this
* 'master-count' property then all the inits based on link
* masks will fail as well.
*
* We will check the hardware capabilities in the startup() step
*/
if (ret) {
dev_err(&adev->dev,
"Failed to read mipi-sdw-master-count: %d\n", ret);
return -EINVAL;
}
/* Check count is within bounds */
if (count > SDW_MAX_LINKS) {
dev_err(&adev->dev, "Link count %d exceeds max %d\n",
count, SDW_MAX_LINKS);
return -EINVAL;
}
if (!count) {
dev_warn(&adev->dev, "No SoundWire links detected\n");
return -EINVAL;
}
dev_dbg(&adev->dev, "ACPI reports %d SDW Link devices\n", count);
info->count = count;
info->link_mask = 0;
for (i = 0; i < count; i++) {
if (ctrl_link_mask && !(ctrl_link_mask & BIT(i))) {
dev_dbg(&adev->dev,
"Link %d masked, will not be enabled\n", i);
continue;
}
if (!is_link_enabled(acpi_fwnode_handle(adev), i)) {
dev_dbg(&adev->dev,
"Link %d not selected in firmware\n", i);
continue;
}
info->link_mask |= BIT(i);
}
return 0;
}
static acpi_status sdw_intel_acpi_cb(acpi_handle handle, u32 level,
void *cdata, void **return_value)
{
struct sdw_intel_acpi_info *info = cdata;
acpi_status status;
u64 adr;
status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &adr);
if (ACPI_FAILURE(status))
return AE_OK; /* keep going */
if (!acpi_fetch_acpi_dev(handle)) {
pr_err("%s: Couldn't find ACPI handle\n", __func__);
return AE_NOT_FOUND;
}
/*
* On some Intel platforms, multiple children of the HDAS
* device can be found, but only one of them is the SoundWire
* controller. The SNDW device is always exposed with
* Name(_ADR, 0x40000000), with bits 31..28 representing the
* SoundWire link so filter accordingly
*/
if (FIELD_GET(GENMASK(31, 28), adr) != SDW_LINK_TYPE)
return AE_OK; /* keep going */
/* found the correct SoundWire controller */
info->handle = handle;
/* device found, stop namespace walk */
return AE_CTRL_TERMINATE;
}
/**
* sdw_intel_acpi_scan() - SoundWire Intel init routine
* @parent_handle: ACPI parent handle
* @info: description of what firmware/DSDT tables expose
*
* This scans the namespace and queries firmware to figure out which
* links to enable. A follow-up use of sdw_intel_probe() and
* sdw_intel_startup() is required for creation of devices and bus
* startup
*/
int sdw_intel_acpi_scan(acpi_handle *parent_handle,
struct sdw_intel_acpi_info *info)
{
acpi_status status;
info->handle = NULL;
/*
* In the HDAS ACPI scope, 'SNDW' may be either the child of
* 'HDAS' or the grandchild of 'HDAS'. So let's go through
* the ACPI from 'HDAS' at max depth of 2 to find the 'SNDW'
* device.
*/
status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
parent_handle, 2,
sdw_intel_acpi_cb,
NULL, info, NULL);
if (ACPI_FAILURE(status) || info->handle == NULL)
return -ENODEV;
return sdw_intel_scan_controller(info);
}
EXPORT_SYMBOL_NS(sdw_intel_acpi_scan, SND_INTEL_SOUNDWIRE_ACPI);
MODULE_LICENSE("Dual BSD/GPL");
MODULE_DESCRIPTION("Intel Soundwire ACPI helpers");