From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- drivers/mfd/max77650.c | 231 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 231 insertions(+) create mode 100644 drivers/mfd/max77650.c (limited to 'drivers/mfd/max77650.c') diff --git a/drivers/mfd/max77650.c b/drivers/mfd/max77650.c new file mode 100644 index 000000000..75b5dc44e --- /dev/null +++ b/drivers/mfd/max77650.c @@ -0,0 +1,231 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright (C) 2018 BayLibre SAS +// Author: Bartosz Golaszewski +// +// Core MFD driver for MAXIM 77650/77651 charger/power-supply. +// Programming manual: https://pdfserv.maximintegrated.com/en/an/AN6428.pdf + +#include +#include +#include +#include +#include +#include +#include +#include + +#define MAX77650_INT_GPI_F_MSK BIT(0) +#define MAX77650_INT_GPI_R_MSK BIT(1) +#define MAX77650_INT_GPI_MSK \ + (MAX77650_INT_GPI_F_MSK | MAX77650_INT_GPI_R_MSK) +#define MAX77650_INT_nEN_F_MSK BIT(2) +#define MAX77650_INT_nEN_R_MSK BIT(3) +#define MAX77650_INT_TJAL1_R_MSK BIT(4) +#define MAX77650_INT_TJAL2_R_MSK BIT(5) +#define MAX77650_INT_DOD_R_MSK BIT(6) + +#define MAX77650_INT_THM_MSK BIT(0) +#define MAX77650_INT_CHG_MSK BIT(1) +#define MAX77650_INT_CHGIN_MSK BIT(2) +#define MAX77650_INT_TJ_REG_MSK BIT(3) +#define MAX77650_INT_CHGIN_CTRL_MSK BIT(4) +#define MAX77650_INT_SYS_CTRL_MSK BIT(5) +#define MAX77650_INT_SYS_CNFG_MSK BIT(6) + +#define MAX77650_INT_GLBL_OFFSET 0 +#define MAX77650_INT_CHG_OFFSET 1 + +#define MAX77650_SBIA_LPM_MASK BIT(5) +#define MAX77650_SBIA_LPM_DISABLED 0x00 + +enum { + MAX77650_INT_GPI, + MAX77650_INT_nEN_F, + MAX77650_INT_nEN_R, + MAX77650_INT_TJAL1_R, + MAX77650_INT_TJAL2_R, + MAX77650_INT_DOD_R, + MAX77650_INT_THM, + MAX77650_INT_CHG, + MAX77650_INT_CHGIN, + MAX77650_INT_TJ_REG, + MAX77650_INT_CHGIN_CTRL, + MAX77650_INT_SYS_CTRL, + MAX77650_INT_SYS_CNFG, +}; + +static const struct resource max77650_charger_resources[] = { + DEFINE_RES_IRQ_NAMED(MAX77650_INT_CHG, "CHG"), + DEFINE_RES_IRQ_NAMED(MAX77650_INT_CHGIN, "CHGIN"), +}; + +static const struct resource max77650_gpio_resources[] = { + DEFINE_RES_IRQ_NAMED(MAX77650_INT_GPI, "GPI"), +}; + +static const struct resource max77650_onkey_resources[] = { + DEFINE_RES_IRQ_NAMED(MAX77650_INT_nEN_F, "nEN_F"), + DEFINE_RES_IRQ_NAMED(MAX77650_INT_nEN_R, "nEN_R"), +}; + +static const struct mfd_cell max77650_cells[] = { + { + .name = "max77650-regulator", + .of_compatible = "maxim,max77650-regulator", + }, { + .name = "max77650-charger", + .of_compatible = "maxim,max77650-charger", + .resources = max77650_charger_resources, + .num_resources = ARRAY_SIZE(max77650_charger_resources), + }, { + .name = "max77650-gpio", + .of_compatible = "maxim,max77650-gpio", + .resources = max77650_gpio_resources, + .num_resources = ARRAY_SIZE(max77650_gpio_resources), + }, { + .name = "max77650-led", + .of_compatible = "maxim,max77650-led", + }, { + .name = "max77650-onkey", + .of_compatible = "maxim,max77650-onkey", + .resources = max77650_onkey_resources, + .num_resources = ARRAY_SIZE(max77650_onkey_resources), + }, +}; + +static const struct regmap_irq max77650_irqs[] = { + [MAX77650_INT_GPI] = { + .reg_offset = MAX77650_INT_GLBL_OFFSET, + .mask = MAX77650_INT_GPI_MSK, + .type = { + .type_falling_val = MAX77650_INT_GPI_F_MSK, + .type_rising_val = MAX77650_INT_GPI_R_MSK, + .types_supported = IRQ_TYPE_EDGE_BOTH, + }, + }, + REGMAP_IRQ_REG(MAX77650_INT_nEN_F, + MAX77650_INT_GLBL_OFFSET, MAX77650_INT_nEN_F_MSK), + REGMAP_IRQ_REG(MAX77650_INT_nEN_R, + MAX77650_INT_GLBL_OFFSET, MAX77650_INT_nEN_R_MSK), + REGMAP_IRQ_REG(MAX77650_INT_TJAL1_R, + MAX77650_INT_GLBL_OFFSET, MAX77650_INT_TJAL1_R_MSK), + REGMAP_IRQ_REG(MAX77650_INT_TJAL2_R, + MAX77650_INT_GLBL_OFFSET, MAX77650_INT_TJAL2_R_MSK), + REGMAP_IRQ_REG(MAX77650_INT_DOD_R, + MAX77650_INT_GLBL_OFFSET, MAX77650_INT_DOD_R_MSK), + REGMAP_IRQ_REG(MAX77650_INT_THM, + MAX77650_INT_CHG_OFFSET, MAX77650_INT_THM_MSK), + REGMAP_IRQ_REG(MAX77650_INT_CHG, + MAX77650_INT_CHG_OFFSET, MAX77650_INT_CHG_MSK), + REGMAP_IRQ_REG(MAX77650_INT_CHGIN, + MAX77650_INT_CHG_OFFSET, MAX77650_INT_CHGIN_MSK), + REGMAP_IRQ_REG(MAX77650_INT_TJ_REG, + MAX77650_INT_CHG_OFFSET, MAX77650_INT_TJ_REG_MSK), + REGMAP_IRQ_REG(MAX77650_INT_CHGIN_CTRL, + MAX77650_INT_CHG_OFFSET, MAX77650_INT_CHGIN_CTRL_MSK), + REGMAP_IRQ_REG(MAX77650_INT_SYS_CTRL, + MAX77650_INT_CHG_OFFSET, MAX77650_INT_SYS_CTRL_MSK), + REGMAP_IRQ_REG(MAX77650_INT_SYS_CNFG, + MAX77650_INT_CHG_OFFSET, MAX77650_INT_SYS_CNFG_MSK), +}; + +static const struct regmap_irq_chip max77650_irq_chip = { + .name = "max77650-irq", + .irqs = max77650_irqs, + .num_irqs = ARRAY_SIZE(max77650_irqs), + .num_regs = 2, + .status_base = MAX77650_REG_INT_GLBL, + .mask_base = MAX77650_REG_INTM_GLBL, + .type_in_mask = true, + .init_ack_masked = true, + .clear_on_unmask = true, +}; + +static const struct regmap_config max77650_regmap_config = { + .name = "max77650", + .reg_bits = 8, + .val_bits = 8, +}; + +static int max77650_i2c_probe(struct i2c_client *i2c) +{ + struct regmap_irq_chip_data *irq_data; + struct device *dev = &i2c->dev; + struct irq_domain *domain; + struct regmap *map; + unsigned int val; + int rv, id; + + map = devm_regmap_init_i2c(i2c, &max77650_regmap_config); + if (IS_ERR(map)) { + dev_err(dev, "Unable to initialise I2C Regmap\n"); + return PTR_ERR(map); + } + + rv = regmap_read(map, MAX77650_REG_CID, &val); + if (rv) { + dev_err(dev, "Unable to read Chip ID\n"); + return rv; + } + + id = MAX77650_CID_BITS(val); + switch (id) { + case MAX77650_CID_77650A: + case MAX77650_CID_77650C: + case MAX77650_CID_77651A: + case MAX77650_CID_77651B: + break; + default: + dev_err(dev, "Chip not supported - ID: 0x%02x\n", id); + return -ENODEV; + } + + /* + * This IC has a low-power mode which reduces the quiescent current + * consumption to ~5.6uA but is only suitable for systems consuming + * less than ~2mA. Since this is not likely the case even on + * linux-based wearables - keep the chip in normal power mode. + */ + rv = regmap_update_bits(map, + MAX77650_REG_CNFG_GLBL, + MAX77650_SBIA_LPM_MASK, + MAX77650_SBIA_LPM_DISABLED); + if (rv) { + dev_err(dev, "Unable to change the power mode\n"); + return rv; + } + + rv = devm_regmap_add_irq_chip(dev, map, i2c->irq, + IRQF_ONESHOT | IRQF_SHARED, 0, + &max77650_irq_chip, &irq_data); + if (rv) { + dev_err(dev, "Unable to add Regmap IRQ chip\n"); + return rv; + } + + domain = regmap_irq_get_domain(irq_data); + + return devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE, + max77650_cells, ARRAY_SIZE(max77650_cells), + NULL, 0, domain); +} + +static const struct of_device_id max77650_of_match[] = { + { .compatible = "maxim,max77650" }, + { } +}; +MODULE_DEVICE_TABLE(of, max77650_of_match); + +static struct i2c_driver max77650_i2c_driver = { + .driver = { + .name = "max77650", + .of_match_table = max77650_of_match, + }, + .probe = max77650_i2c_probe, +}; +module_i2c_driver(max77650_i2c_driver); + +MODULE_DESCRIPTION("MAXIM 77650/77651 multi-function core driver"); +MODULE_AUTHOR("Bartosz Golaszewski "); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1