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/max77541.c | 220 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 220 insertions(+) create mode 100644 drivers/mfd/max77541.c (limited to 'drivers/mfd/max77541.c') diff --git a/drivers/mfd/max77541.c b/drivers/mfd/max77541.c new file mode 100644 index 000000000..f91b4f537 --- /dev/null +++ b/drivers/mfd/max77541.c @@ -0,0 +1,220 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2022 Analog Devices, Inc. + * Driver for the MAX77540 and MAX77541 + */ + +#include +#include +#include +#include +#include +#include + +static const struct regmap_config max77541_regmap_config = { + .reg_bits = 8, + .val_bits = 8, +}; + +static const struct regmap_irq max77541_src_irqs[] = { + { .mask = MAX77541_BIT_INT_SRC_TOPSYS }, + { .mask = MAX77541_BIT_INT_SRC_BUCK }, +}; + +static const struct regmap_irq_chip max77541_src_irq_chip = { + .name = "max77541-src", + .status_base = MAX77541_REG_INT_SRC, + .mask_base = MAX77541_REG_INT_SRC_M, + .num_regs = 1, + .irqs = max77541_src_irqs, + .num_irqs = ARRAY_SIZE(max77541_src_irqs), +}; + +static const struct regmap_irq max77541_topsys_irqs[] = { + { .mask = MAX77541_BIT_TOPSYS_INT_TJ_120C }, + { .mask = MAX77541_BIT_TOPSYS_INT_TJ_140C }, + { .mask = MAX77541_BIT_TOPSYS_INT_TSHDN }, + { .mask = MAX77541_BIT_TOPSYS_INT_UVLO }, + { .mask = MAX77541_BIT_TOPSYS_INT_ALT_SWO }, + { .mask = MAX77541_BIT_TOPSYS_INT_EXT_FREQ_DET }, +}; + +static const struct regmap_irq_chip max77541_topsys_irq_chip = { + .name = "max77541-topsys", + .status_base = MAX77541_REG_TOPSYS_INT, + .mask_base = MAX77541_REG_TOPSYS_INT_M, + .num_regs = 1, + .irqs = max77541_topsys_irqs, + .num_irqs = ARRAY_SIZE(max77541_topsys_irqs), +}; + +static const struct regmap_irq max77541_buck_irqs[] = { + { .mask = MAX77541_BIT_BUCK_INT_M1_POK_FLT }, + { .mask = MAX77541_BIT_BUCK_INT_M2_POK_FLT }, + { .mask = MAX77541_BIT_BUCK_INT_M1_SCFLT }, + { .mask = MAX77541_BIT_BUCK_INT_M2_SCFLT }, +}; + +static const struct regmap_irq_chip max77541_buck_irq_chip = { + .name = "max77541-buck", + .status_base = MAX77541_REG_BUCK_INT, + .mask_base = MAX77541_REG_BUCK_INT_M, + .num_regs = 1, + .irqs = max77541_buck_irqs, + .num_irqs = ARRAY_SIZE(max77541_buck_irqs), +}; + +static const struct regmap_irq max77541_adc_irqs[] = { + { .mask = MAX77541_BIT_ADC_INT_CH1_I }, + { .mask = MAX77541_BIT_ADC_INT_CH2_I }, + { .mask = MAX77541_BIT_ADC_INT_CH3_I }, + { .mask = MAX77541_BIT_ADC_INT_CH6_I }, +}; + +static const struct regmap_irq_chip max77541_adc_irq_chip = { + .name = "max77541-adc", + .status_base = MAX77541_REG_ADC_INT, + .mask_base = MAX77541_REG_ADC_INT_M, + .num_regs = 1, + .irqs = max77541_adc_irqs, + .num_irqs = ARRAY_SIZE(max77541_adc_irqs), +}; + +static const struct mfd_cell max77540_devs[] = { + MFD_CELL_OF("max77540-regulator", NULL, NULL, 0, 0, NULL), +}; + +static const struct mfd_cell max77541_devs[] = { + MFD_CELL_OF("max77541-regulator", NULL, NULL, 0, 0, NULL), + MFD_CELL_OF("max77541-adc", NULL, NULL, 0, 0, NULL), +}; + +static int max77541_pmic_irq_init(struct device *dev) +{ + struct max77541 *max77541 = dev_get_drvdata(dev); + int irq = max77541->i2c->irq; + int ret; + + ret = devm_regmap_add_irq_chip(dev, max77541->regmap, irq, + IRQF_ONESHOT | IRQF_SHARED, 0, + &max77541_src_irq_chip, + &max77541->irq_data); + if (ret) + return ret; + + ret = devm_regmap_add_irq_chip(dev, max77541->regmap, irq, + IRQF_ONESHOT | IRQF_SHARED, 0, + &max77541_topsys_irq_chip, + &max77541->irq_topsys); + if (ret) + return ret; + + ret = devm_regmap_add_irq_chip(dev, max77541->regmap, irq, + IRQF_ONESHOT | IRQF_SHARED, 0, + &max77541_buck_irq_chip, + &max77541->irq_buck); + if (ret) + return ret; + + if (max77541->id == MAX77541) { + ret = devm_regmap_add_irq_chip(dev, max77541->regmap, irq, + IRQF_ONESHOT | IRQF_SHARED, 0, + &max77541_adc_irq_chip, + &max77541->irq_adc); + if (ret) + return ret; + } + + return 0; +} + +static int max77541_pmic_setup(struct device *dev) +{ + struct max77541 *max77541 = dev_get_drvdata(dev); + const struct mfd_cell *cells; + int n_devs; + int ret; + + switch (max77541->id) { + case MAX77540: + cells = max77540_devs; + n_devs = ARRAY_SIZE(max77540_devs); + break; + case MAX77541: + cells = max77541_devs; + n_devs = ARRAY_SIZE(max77541_devs); + break; + default: + return -EINVAL; + } + + ret = max77541_pmic_irq_init(dev); + if (ret) + return dev_err_probe(dev, ret, "Failed to initialize IRQ\n"); + + ret = devm_device_init_wakeup(dev); + if (ret) + return dev_err_probe(dev, ret, "Unable to init wakeup\n"); + + return devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE, + cells, n_devs, NULL, 0, NULL); +} + +static int max77541_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct max77541 *max77541; + + max77541 = devm_kzalloc(dev, sizeof(*max77541), GFP_KERNEL); + if (!max77541) + return -ENOMEM; + + i2c_set_clientdata(client, max77541); + max77541->i2c = client; + + max77541->id = (uintptr_t)i2c_get_match_data(client); + if (!max77541->id) + return -EINVAL; + + max77541->regmap = devm_regmap_init_i2c(client, + &max77541_regmap_config); + if (IS_ERR(max77541->regmap)) + return dev_err_probe(dev, PTR_ERR(max77541->regmap), + "Failed to allocate register map\n"); + + return max77541_pmic_setup(dev); +} + +static const struct of_device_id max77541_of_id[] = { + { + .compatible = "adi,max77540", + .data = (void *)MAX77540, + }, + { + .compatible = "adi,max77541", + .data = (void *)MAX77541, + }, + { } +}; +MODULE_DEVICE_TABLE(of, max77541_of_id); + +static const struct i2c_device_id max77541_id[] = { + { "max77540", MAX77540 }, + { "max77541", MAX77541 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, max77541_id); + +static struct i2c_driver max77541_driver = { + .driver = { + .name = "max77541", + .of_match_table = max77541_of_id, + }, + .probe = max77541_probe, + .id_table = max77541_id, +}; +module_i2c_driver(max77541_driver); + +MODULE_DESCRIPTION("MAX7740/MAX7741 Driver"); +MODULE_AUTHOR("Okan Sahin "); +MODULE_LICENSE("GPL"); -- cgit v1.3.1