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/input/misc/ad714x-spi.c | 103 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 103 insertions(+) create mode 100644 drivers/input/misc/ad714x-spi.c (limited to 'drivers/input/misc/ad714x-spi.c') diff --git a/drivers/input/misc/ad714x-spi.c b/drivers/input/misc/ad714x-spi.c new file mode 100644 index 000000000..eb13b4cd6 --- /dev/null +++ b/drivers/input/misc/ad714x-spi.c @@ -0,0 +1,103 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * AD714X CapTouch Programmable Controller driver (SPI bus) + * + * Copyright 2009-2011 Analog Devices Inc. + */ + +#include /* BUS_SPI */ +#include +#include +#include +#include +#include "ad714x.h" + +#define AD714x_SPI_CMD_PREFIX 0xE000 /* bits 15:11 */ +#define AD714x_SPI_READ BIT(10) + +static int ad714x_spi_read(struct ad714x_chip *chip, + unsigned short reg, unsigned short *data, size_t len) +{ + struct spi_device *spi = to_spi_device(chip->dev); + struct spi_message message; + struct spi_transfer xfer[2]; + int i; + int error; + + spi_message_init(&message); + memset(xfer, 0, sizeof(xfer)); + + chip->xfer_buf[0] = cpu_to_be16(AD714x_SPI_CMD_PREFIX | + AD714x_SPI_READ | reg); + xfer[0].tx_buf = &chip->xfer_buf[0]; + xfer[0].len = sizeof(chip->xfer_buf[0]); + spi_message_add_tail(&xfer[0], &message); + + xfer[1].rx_buf = &chip->xfer_buf[1]; + xfer[1].len = sizeof(chip->xfer_buf[1]) * len; + spi_message_add_tail(&xfer[1], &message); + + error = spi_sync(spi, &message); + if (unlikely(error)) { + dev_err(chip->dev, "SPI read error: %d\n", error); + return error; + } + + for (i = 0; i < len; i++) + data[i] = be16_to_cpu(chip->xfer_buf[i + 1]); + + return 0; +} + +static int ad714x_spi_write(struct ad714x_chip *chip, + unsigned short reg, unsigned short data) +{ + struct spi_device *spi = to_spi_device(chip->dev); + int error; + + chip->xfer_buf[0] = cpu_to_be16(AD714x_SPI_CMD_PREFIX | reg); + chip->xfer_buf[1] = cpu_to_be16(data); + + error = spi_write(spi, (u8 *)chip->xfer_buf, + 2 * sizeof(*chip->xfer_buf)); + if (unlikely(error)) { + dev_err(chip->dev, "SPI write error: %d\n", error); + return error; + } + + return 0; +} + +static int ad714x_spi_probe(struct spi_device *spi) +{ + struct ad714x_chip *chip; + int err; + + spi->bits_per_word = 8; + err = spi_setup(spi); + if (err < 0) + return err; + + chip = ad714x_probe(&spi->dev, BUS_SPI, spi->irq, + ad714x_spi_read, ad714x_spi_write); + if (IS_ERR(chip)) + return PTR_ERR(chip); + + spi_set_drvdata(spi, chip); + + return 0; +} + +static struct spi_driver ad714x_spi_driver = { + .driver = { + .name = "ad714x_captouch", + .pm = pm_sleep_ptr(&ad714x_pm), + }, + .probe = ad714x_spi_probe, +}; + +module_spi_driver(ad714x_spi_driver); + +MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor SPI Bus Driver"); +MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1