From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Thu, 3 Sep 2026 10:43:25 -0500 Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init() The local "root" pointer is a temporary variable used during the device search. Therefore, refcount related to the search iterators should be cleaned up after the search is complete. Use the __free() cleanup macro to ensure the refcount is decremented when the temporary pointer goes out of scope. Additionally, increment the refcount when caching a root pointer. This ensures the in-use refcount is separate from the temporary search refcounting. Finally, drop the redundant "root = NULL" before the second search loop. The pci_get_class() iterator always decrements the refcount of its "from" argument, so the first loop can only fall through with "root" already NULL. Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com Reported-by: Sashiko Assisted-by: LLM Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Mario Limonciello (AMD) Cc: Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com --- drivers/base/regmap/regmap-sdw.c | 102 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 102 insertions(+) create mode 100644 drivers/base/regmap/regmap-sdw.c (limited to 'drivers/base/regmap/regmap-sdw.c') diff --git a/drivers/base/regmap/regmap-sdw.c b/drivers/base/regmap/regmap-sdw.c new file mode 100644 index 000000000..ea631ac7c --- /dev/null +++ b/drivers/base/regmap/regmap-sdw.c @@ -0,0 +1,102 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright(c) 2015-17 Intel Corporation. + +#include +#include +#include +#include +#include +#include +#include "internal.h" + +static int regmap_sdw_write(void *context, const void *val_buf, size_t val_size) +{ + struct device *dev = context; + struct sdw_slave *slave = dev_to_sdw_dev(dev); + /* First word of buffer contains the destination address */ + u32 addr = le32_to_cpu(*(const __le32 *)val_buf); + const u8 *val = val_buf; + + return sdw_nwrite_no_pm(slave, addr, val_size - sizeof(addr), val + sizeof(addr)); +} + +static int regmap_sdw_gather_write(void *context, + const void *reg_buf, size_t reg_size, + const void *val_buf, size_t val_size) +{ + struct device *dev = context; + struct sdw_slave *slave = dev_to_sdw_dev(dev); + u32 addr = le32_to_cpu(*(const __le32 *)reg_buf); + + return sdw_nwrite_no_pm(slave, addr, val_size, val_buf); +} + +static int regmap_sdw_read(void *context, + const void *reg_buf, size_t reg_size, + void *val_buf, size_t val_size) +{ + struct device *dev = context; + struct sdw_slave *slave = dev_to_sdw_dev(dev); + u32 addr = le32_to_cpu(*(const __le32 *)reg_buf); + + return sdw_nread_no_pm(slave, addr, val_size, val_buf); +} + +static const struct regmap_bus regmap_sdw = { + .write = regmap_sdw_write, + .gather_write = regmap_sdw_gather_write, + .read = regmap_sdw_read, + .reg_format_endian_default = REGMAP_ENDIAN_LITTLE, + .val_format_endian_default = REGMAP_ENDIAN_LITTLE, +}; + +static int regmap_sdw_config_check(const struct regmap_config *config) +{ + /* Register addresses are 32 bits wide */ + if (config->reg_bits != 32) + return -ENOTSUPP; + + if (config->pad_bits != 0) + return -ENOTSUPP; + + /* Only bulk writes are supported not multi-register writes */ + if (config->can_multi_write) + return -ENOTSUPP; + + return 0; +} + +struct regmap *__regmap_init_sdw(struct sdw_slave *sdw, + const struct regmap_config *config, + struct lock_class_key *lock_key, + const char *lock_name) +{ + int ret; + + ret = regmap_sdw_config_check(config); + if (ret) + return ERR_PTR(ret); + + return __regmap_init(&sdw->dev, ®map_sdw, + &sdw->dev, config, lock_key, lock_name); +} +EXPORT_SYMBOL_GPL(__regmap_init_sdw); + +struct regmap *__devm_regmap_init_sdw(struct sdw_slave *sdw, + const struct regmap_config *config, + struct lock_class_key *lock_key, + const char *lock_name) +{ + int ret; + + ret = regmap_sdw_config_check(config); + if (ret) + return ERR_PTR(ret); + + return __devm_regmap_init(&sdw->dev, ®map_sdw, + &sdw->dev, config, lock_key, lock_name); +} +EXPORT_SYMBOL_GPL(__devm_regmap_init_sdw); + +MODULE_DESCRIPTION("regmap SoundWire Module"); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1