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/regulator/mp886x.c | 370 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 370 insertions(+) create mode 100644 drivers/regulator/mp886x.c (limited to 'drivers/regulator/mp886x.c') diff --git a/drivers/regulator/mp886x.c b/drivers/regulator/mp886x.c new file mode 100644 index 000000000..e0b62bc02 --- /dev/null +++ b/drivers/regulator/mp886x.c @@ -0,0 +1,370 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// MP8867/MP8869 regulator driver +// +// Copyright (C) 2020 Synaptics Incorporated +// +// Author: Jisheng Zhang + +#include +#include +#include +#include +#include +#include +#include + +#define MP886X_VSEL 0x00 +#define MP886X_V_BOOT (1 << 7) +#define MP886X_SYSCNTLREG1 0x01 +#define MP886X_MODE (1 << 0) +#define MP886X_SLEW_SHIFT 3 +#define MP886X_SLEW_MASK (0x7 << MP886X_SLEW_SHIFT) +#define MP886X_GO (1 << 6) +#define MP886X_EN (1 << 7) +#define MP8869_SYSCNTLREG2 0x02 + +struct mp886x_cfg_info { + const struct regulator_ops *rops; + const unsigned int slew_rates[8]; + const int switch_freq[4]; + const u8 fs_reg; + const u8 fs_shift; +}; + +struct mp886x_device_info { + struct device *dev; + struct regulator_desc desc; + struct regulator_init_data *regulator; + struct gpio_desc *en_gpio; + const struct mp886x_cfg_info *ci; + u32 r[2]; + unsigned int sel; +}; + +static void mp886x_set_switch_freq(struct mp886x_device_info *di, + struct regmap *regmap, + u32 freq) +{ + const struct mp886x_cfg_info *ci = di->ci; + int i; + + for (i = 0; i < ARRAY_SIZE(ci->switch_freq); i++) { + if (freq == ci->switch_freq[i]) { + regmap_update_bits(regmap, ci->fs_reg, + 0x3 << ci->fs_shift, i << ci->fs_shift); + return; + } + } + + dev_err(di->dev, "invalid frequency %d\n", freq); +} + +static int mp886x_set_mode(struct regulator_dev *rdev, unsigned int mode) +{ + switch (mode) { + case REGULATOR_MODE_FAST: + regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1, + MP886X_MODE, MP886X_MODE); + break; + case REGULATOR_MODE_NORMAL: + regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1, + MP886X_MODE, 0); + break; + default: + return -EINVAL; + } + return 0; +} + +static unsigned int mp886x_get_mode(struct regulator_dev *rdev) +{ + u32 val; + int ret; + + ret = regmap_read(rdev->regmap, MP886X_SYSCNTLREG1, &val); + if (ret < 0) + return ret; + if (val & MP886X_MODE) + return REGULATOR_MODE_FAST; + else + return REGULATOR_MODE_NORMAL; +} + +static int mp8869_set_voltage_sel(struct regulator_dev *rdev, unsigned int sel) +{ + int ret; + + ret = regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1, + MP886X_GO, MP886X_GO); + if (ret < 0) + return ret; + + sel <<= ffs(rdev->desc->vsel_mask) - 1; + return regmap_update_bits(rdev->regmap, rdev->desc->vsel_reg, + MP886X_V_BOOT | rdev->desc->vsel_mask, sel); +} + +static inline unsigned int mp8869_scale(unsigned int uv, u32 r1, u32 r2) +{ + u32 tmp = uv * r1 / r2; + + return uv + tmp; +} + +static int mp8869_get_voltage_sel(struct regulator_dev *rdev) +{ + struct mp886x_device_info *di = rdev_get_drvdata(rdev); + int ret, uv; + unsigned int val; + bool fbloop; + + ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val); + if (ret) + return ret; + + fbloop = val & MP886X_V_BOOT; + if (fbloop) { + uv = rdev->desc->min_uV; + uv = mp8869_scale(uv, di->r[0], di->r[1]); + return regulator_map_voltage_linear(rdev, uv, uv); + } + + val &= rdev->desc->vsel_mask; + val >>= ffs(rdev->desc->vsel_mask) - 1; + + return val; +} + +static const struct regulator_ops mp8869_regulator_ops = { + .set_voltage_sel = mp8869_set_voltage_sel, + .get_voltage_sel = mp8869_get_voltage_sel, + .set_voltage_time_sel = regulator_set_voltage_time_sel, + .map_voltage = regulator_map_voltage_linear, + .list_voltage = regulator_list_voltage_linear, + .enable = regulator_enable_regmap, + .disable = regulator_disable_regmap, + .is_enabled = regulator_is_enabled_regmap, + .set_mode = mp886x_set_mode, + .get_mode = mp886x_get_mode, + .set_ramp_delay = regulator_set_ramp_delay_regmap, +}; + +static const struct mp886x_cfg_info mp8869_ci = { + .rops = &mp8869_regulator_ops, + .slew_rates = { + 40000, + 30000, + 20000, + 10000, + 5000, + 2500, + 1250, + 625, + }, + .switch_freq = { + 500000, + 750000, + 1000000, + 1250000, + }, + .fs_reg = MP8869_SYSCNTLREG2, + .fs_shift = 4, +}; + +static int mp8867_set_voltage_sel(struct regulator_dev *rdev, unsigned int sel) +{ + struct mp886x_device_info *di = rdev_get_drvdata(rdev); + int ret, delta; + + ret = mp8869_set_voltage_sel(rdev, sel); + if (ret < 0) + return ret; + + delta = di->sel - sel; + if (abs(delta) <= 5) + ret = regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1, + MP886X_GO, 0); + di->sel = sel; + + return ret; +} + +static int mp8867_get_voltage_sel(struct regulator_dev *rdev) +{ + struct mp886x_device_info *di = rdev_get_drvdata(rdev); + int ret, uv; + unsigned int val; + bool fbloop; + + ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val); + if (ret) + return ret; + + fbloop = val & MP886X_V_BOOT; + + val &= rdev->desc->vsel_mask; + val >>= ffs(rdev->desc->vsel_mask) - 1; + + if (fbloop) { + uv = regulator_list_voltage_linear(rdev, val); + uv = mp8869_scale(uv, di->r[0], di->r[1]); + return regulator_map_voltage_linear(rdev, uv, uv); + } + + return val; +} + +static const struct regulator_ops mp8867_regulator_ops = { + .set_voltage_sel = mp8867_set_voltage_sel, + .get_voltage_sel = mp8867_get_voltage_sel, + .set_voltage_time_sel = regulator_set_voltage_time_sel, + .map_voltage = regulator_map_voltage_linear, + .list_voltage = regulator_list_voltage_linear, + .enable = regulator_enable_regmap, + .disable = regulator_disable_regmap, + .is_enabled = regulator_is_enabled_regmap, + .set_mode = mp886x_set_mode, + .get_mode = mp886x_get_mode, + .set_ramp_delay = regulator_set_ramp_delay_regmap, +}; + +static const struct mp886x_cfg_info mp8867_ci = { + .rops = &mp8867_regulator_ops, + .slew_rates = { + 64000, + 32000, + 16000, + 8000, + 4000, + 2000, + 1000, + 500, + }, + .switch_freq = { + 500000, + 750000, + 1000000, + 1500000, + }, + .fs_reg = MP886X_SYSCNTLREG1, + .fs_shift = 1, +}; + +static int mp886x_regulator_register(struct mp886x_device_info *di, + struct regulator_config *config) +{ + struct regulator_desc *rdesc = &di->desc; + struct regulator_dev *rdev; + + rdesc->name = "mp886x-reg"; + rdesc->supply_name = "vin"; + rdesc->ops = di->ci->rops; + rdesc->type = REGULATOR_VOLTAGE; + rdesc->n_voltages = 128; + rdesc->enable_reg = MP886X_SYSCNTLREG1; + rdesc->enable_mask = MP886X_EN; + rdesc->min_uV = 600000; + rdesc->uV_step = 10000; + rdesc->vsel_reg = MP886X_VSEL; + rdesc->vsel_mask = 0x3f; + rdesc->ramp_reg = MP886X_SYSCNTLREG1; + rdesc->ramp_mask = MP886X_SLEW_MASK; + rdesc->ramp_delay_table = di->ci->slew_rates; + rdesc->n_ramp_values = ARRAY_SIZE(di->ci->slew_rates); + rdesc->owner = THIS_MODULE; + + rdev = devm_regulator_register(di->dev, &di->desc, config); + if (IS_ERR(rdev)) + return PTR_ERR(rdev); + di->sel = rdesc->ops->get_voltage_sel(rdev); + return 0; +} + +static const struct regmap_config mp886x_regmap_config = { + .reg_bits = 8, + .val_bits = 8, +}; + +static int mp886x_i2c_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct device_node *np = dev->of_node; + struct mp886x_device_info *di; + struct regulator_config config = { }; + struct regmap *regmap; + u32 freq; + int ret; + + di = devm_kzalloc(dev, sizeof(struct mp886x_device_info), GFP_KERNEL); + if (!di) + return -ENOMEM; + + di->regulator = of_get_regulator_init_data(dev, np, &di->desc); + if (!di->regulator) { + dev_err(dev, "Platform data not found!\n"); + return -EINVAL; + } + + ret = of_property_read_u32_array(np, "mps,fb-voltage-divider", + di->r, 2); + if (ret) + return ret; + + di->en_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_HIGH); + if (IS_ERR(di->en_gpio)) + return PTR_ERR(di->en_gpio); + + di->ci = i2c_get_match_data(client); + di->dev = dev; + + regmap = devm_regmap_init_i2c(client, &mp886x_regmap_config); + if (IS_ERR(regmap)) { + dev_err(dev, "Failed to allocate regmap!\n"); + return PTR_ERR(regmap); + } + i2c_set_clientdata(client, di); + + config.dev = di->dev; + config.init_data = di->regulator; + config.regmap = regmap; + config.driver_data = di; + config.of_node = np; + + if (!of_property_read_u32(np, "mps,switch-frequency-hz", &freq)) + mp886x_set_switch_freq(di, regmap, freq); + + ret = mp886x_regulator_register(di, &config); + if (ret < 0) + dev_err(dev, "Failed to register regulator!\n"); + return ret; +} + +static const struct of_device_id mp886x_dt_ids[] = { + { .compatible = "mps,mp8867", .data = &mp8867_ci }, + { .compatible = "mps,mp8869", .data = &mp8869_ci }, + { } +}; +MODULE_DEVICE_TABLE(of, mp886x_dt_ids); + +static const struct i2c_device_id mp886x_id[] = { + { .name = "mp8867", .driver_data = (kernel_ulong_t)&mp8867_ci }, + { .name = "mp8869", .driver_data = (kernel_ulong_t)&mp8869_ci }, + { } +}; +MODULE_DEVICE_TABLE(i2c, mp886x_id); + +static struct i2c_driver mp886x_regulator_driver = { + .driver = { + .name = "mp886x-regulator", + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + .of_match_table = mp886x_dt_ids, + }, + .probe = mp886x_i2c_probe, + .id_table = mp886x_id, +}; +module_i2c_driver(mp886x_regulator_driver); + +MODULE_AUTHOR("Jisheng Zhang "); +MODULE_DESCRIPTION("MP886x regulator driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1