diff options
Diffstat (limited to 'drivers/misc/tps6594-pfsm.c')
| -rw-r--r-- | drivers/misc/tps6594-pfsm.c | 303 |
1 files changed, 303 insertions, 0 deletions
diff --git a/drivers/misc/tps6594-pfsm.c b/drivers/misc/tps6594-pfsm.c new file mode 100644 index 0000000000..88dcac8148 --- /dev/null +++ b/drivers/misc/tps6594-pfsm.c @@ -0,0 +1,303 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PFSM (Pre-configurable Finite State Machine) driver for TI TPS6594/TPS6593/LP8764 PMICs + * + * Copyright (C) 2023 BayLibre Incorporated - https://www.baylibre.com/ + */ + +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/interrupt.h> +#include <linux/ioctl.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +#include <linux/mfd/tps6594.h> + +#include <linux/tps6594_pfsm.h> + +#define TPS6594_STARTUP_DEST_MCU_ONLY_VAL 2 +#define TPS6594_STARTUP_DEST_ACTIVE_VAL 3 +#define TPS6594_STARTUP_DEST_SHIFT 5 +#define TPS6594_STARTUP_DEST_MCU_ONLY (TPS6594_STARTUP_DEST_MCU_ONLY_VAL \ + << TPS6594_STARTUP_DEST_SHIFT) +#define TPS6594_STARTUP_DEST_ACTIVE (TPS6594_STARTUP_DEST_ACTIVE_VAL \ + << TPS6594_STARTUP_DEST_SHIFT) + +/* + * To update the PMIC firmware, the user must be able to access + * page 0 (user registers) and page 1 (NVM control and configuration). + */ +#define TPS6594_PMIC_MAX_POS 0x200 + +#define TPS6594_FILE_TO_PFSM(f) container_of((f)->private_data, struct tps6594_pfsm, miscdev) + +/** + * struct tps6594_pfsm - device private data structure + * + * @miscdev: misc device infos + * @regmap: regmap for accessing the device registers + */ +struct tps6594_pfsm { + struct miscdevice miscdev; + struct regmap *regmap; +}; + +static ssize_t tps6594_pfsm_read(struct file *f, char __user *buf, + size_t count, loff_t *ppos) +{ + struct tps6594_pfsm *pfsm = TPS6594_FILE_TO_PFSM(f); + loff_t pos = *ppos; + unsigned int val; + int ret; + int i; + + if (pos < 0) + return -EINVAL; + if (pos >= TPS6594_PMIC_MAX_POS) + return 0; + if (count > TPS6594_PMIC_MAX_POS - pos) + count = TPS6594_PMIC_MAX_POS - pos; + + for (i = 0 ; i < count ; i++) { + ret = regmap_read(pfsm->regmap, pos + i, &val); + if (ret) + return ret; + + if (put_user(val, buf + i)) + return -EFAULT; + } + + *ppos = pos + count; + + return count; +} + +static ssize_t tps6594_pfsm_write(struct file *f, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct tps6594_pfsm *pfsm = TPS6594_FILE_TO_PFSM(f); + loff_t pos = *ppos; + char val; + int ret; + int i; + + if (pos < 0) + return -EINVAL; + if (pos >= TPS6594_PMIC_MAX_POS || !count) + return 0; + if (count > TPS6594_PMIC_MAX_POS - pos) + count = TPS6594_PMIC_MAX_POS - pos; + + for (i = 0 ; i < count ; i++) { + if (get_user(val, buf + i)) + return -EFAULT; + + ret = regmap_write(pfsm->regmap, pos + i, val); + if (ret) + return ret; + } + + *ppos = pos + count; + + return count; +} + +static int tps6594_pfsm_configure_ret_trig(struct regmap *regmap, u8 gpio_ret, u8 ddr_ret) +{ + int ret; + + if (gpio_ret) + ret = regmap_set_bits(regmap, TPS6594_REG_FSM_I2C_TRIGGERS, + TPS6594_BIT_TRIGGER_I2C(5) | TPS6594_BIT_TRIGGER_I2C(6)); + else + ret = regmap_clear_bits(regmap, TPS6594_REG_FSM_I2C_TRIGGERS, + TPS6594_BIT_TRIGGER_I2C(5) | TPS6594_BIT_TRIGGER_I2C(6)); + if (ret) + return ret; + + if (ddr_ret) + ret = regmap_set_bits(regmap, TPS6594_REG_FSM_I2C_TRIGGERS, + TPS6594_BIT_TRIGGER_I2C(7)); + else + ret = regmap_clear_bits(regmap, TPS6594_REG_FSM_I2C_TRIGGERS, + TPS6594_BIT_TRIGGER_I2C(7)); + + return ret; +} + +static long tps6594_pfsm_ioctl(struct file *f, unsigned int cmd, unsigned long arg) +{ + struct tps6594_pfsm *pfsm = TPS6594_FILE_TO_PFSM(f); + struct pmic_state_opt state_opt; + void __user *argp = (void __user *)arg; + int ret = -ENOIOCTLCMD; + + switch (cmd) { + case PMIC_GOTO_STANDBY: + /* Disable LP mode */ + ret = regmap_clear_bits(pfsm->regmap, TPS6594_REG_RTC_CTRL_2, + TPS6594_BIT_LP_STANDBY_SEL); + if (ret) + return ret; + + /* Force trigger */ + ret = regmap_write_bits(pfsm->regmap, TPS6594_REG_FSM_I2C_TRIGGERS, + TPS6594_BIT_TRIGGER_I2C(0), TPS6594_BIT_TRIGGER_I2C(0)); + break; + case PMIC_GOTO_LP_STANDBY: + /* Enable LP mode */ + ret = regmap_set_bits(pfsm->regmap, TPS6594_REG_RTC_CTRL_2, + TPS6594_BIT_LP_STANDBY_SEL); + if (ret) + return ret; + + /* Force trigger */ + ret = regmap_write_bits(pfsm->regmap, TPS6594_REG_FSM_I2C_TRIGGERS, + TPS6594_BIT_TRIGGER_I2C(0), TPS6594_BIT_TRIGGER_I2C(0)); + break; + case PMIC_UPDATE_PGM: + /* Force trigger */ + ret = regmap_write_bits(pfsm->regmap, TPS6594_REG_FSM_I2C_TRIGGERS, + TPS6594_BIT_TRIGGER_I2C(3), TPS6594_BIT_TRIGGER_I2C(3)); + break; + case PMIC_SET_ACTIVE_STATE: + /* Modify NSLEEP1-2 bits */ + ret = regmap_set_bits(pfsm->regmap, TPS6594_REG_FSM_NSLEEP_TRIGGERS, + TPS6594_BIT_NSLEEP1B | TPS6594_BIT_NSLEEP2B); + break; + case PMIC_SET_MCU_ONLY_STATE: + if (copy_from_user(&state_opt, argp, sizeof(state_opt))) + return -EFAULT; + + /* Configure retention triggers */ + ret = tps6594_pfsm_configure_ret_trig(pfsm->regmap, state_opt.gpio_retention, + state_opt.ddr_retention); + if (ret) + return ret; + + /* Modify NSLEEP1-2 bits */ + ret = regmap_clear_bits(pfsm->regmap, TPS6594_REG_FSM_NSLEEP_TRIGGERS, + TPS6594_BIT_NSLEEP1B); + if (ret) + return ret; + + ret = regmap_set_bits(pfsm->regmap, TPS6594_REG_FSM_NSLEEP_TRIGGERS, + TPS6594_BIT_NSLEEP2B); + break; + case PMIC_SET_RETENTION_STATE: + if (copy_from_user(&state_opt, argp, sizeof(state_opt))) + return -EFAULT; + + /* Configure wake-up destination */ + if (state_opt.mcu_only_startup_dest) + ret = regmap_write_bits(pfsm->regmap, TPS6594_REG_RTC_CTRL_2, + TPS6594_MASK_STARTUP_DEST, + TPS6594_STARTUP_DEST_MCU_ONLY); + else + ret = regmap_write_bits(pfsm->regmap, TPS6594_REG_RTC_CTRL_2, + TPS6594_MASK_STARTUP_DEST, + TPS6594_STARTUP_DEST_ACTIVE); + if (ret) + return ret; + + /* Configure retention triggers */ + ret = tps6594_pfsm_configure_ret_trig(pfsm->regmap, state_opt.gpio_retention, + state_opt.ddr_retention); + if (ret) + return ret; + + /* Modify NSLEEP1-2 bits */ + ret = regmap_clear_bits(pfsm->regmap, TPS6594_REG_FSM_NSLEEP_TRIGGERS, + TPS6594_BIT_NSLEEP2B); + break; + } + + return ret; +} + +static const struct file_operations tps6594_pfsm_fops = { + .owner = THIS_MODULE, + .llseek = generic_file_llseek, + .read = tps6594_pfsm_read, + .write = tps6594_pfsm_write, + .unlocked_ioctl = tps6594_pfsm_ioctl, + .compat_ioctl = compat_ptr_ioctl, +}; + +static irqreturn_t tps6594_pfsm_isr(int irq, void *dev_id) +{ + struct platform_device *pdev = dev_id; + int i; + + for (i = 0 ; i < pdev->num_resources ; i++) { + if (irq == platform_get_irq_byname(pdev, pdev->resource[i].name)) { + dev_err(pdev->dev.parent, "%s event detected\n", pdev->resource[i].name); + return IRQ_HANDLED; + } + } + + return IRQ_NONE; +} + +static int tps6594_pfsm_probe(struct platform_device *pdev) +{ + struct tps6594_pfsm *pfsm; + struct tps6594 *tps = dev_get_drvdata(pdev->dev.parent); + struct device *dev = &pdev->dev; + int irq; + int ret; + int i; + + pfsm = devm_kzalloc(dev, sizeof(struct tps6594_pfsm), GFP_KERNEL); + if (!pfsm) + return -ENOMEM; + + pfsm->regmap = tps->regmap; + + pfsm->miscdev.minor = MISC_DYNAMIC_MINOR; + pfsm->miscdev.name = devm_kasprintf(dev, GFP_KERNEL, "pfsm-%ld-0x%02x", + tps->chip_id, tps->reg); + pfsm->miscdev.fops = &tps6594_pfsm_fops; + pfsm->miscdev.parent = dev->parent; + + for (i = 0 ; i < pdev->num_resources ; i++) { + irq = platform_get_irq_byname(pdev, pdev->resource[i].name); + if (irq < 0) + return irq; + + ret = devm_request_threaded_irq(dev, irq, NULL, + tps6594_pfsm_isr, IRQF_ONESHOT, + pdev->resource[i].name, pdev); + if (ret) + return dev_err_probe(dev, ret, "Failed to request irq\n"); + } + + platform_set_drvdata(pdev, pfsm); + + return misc_register(&pfsm->miscdev); +} + +static void tps6594_pfsm_remove(struct platform_device *pdev) +{ + struct tps6594_pfsm *pfsm = platform_get_drvdata(pdev); + + misc_deregister(&pfsm->miscdev); +} + +static struct platform_driver tps6594_pfsm_driver = { + .driver = { + .name = "tps6594-pfsm", + }, + .probe = tps6594_pfsm_probe, + .remove_new = tps6594_pfsm_remove, +}; + +module_platform_driver(tps6594_pfsm_driver); + +MODULE_ALIAS("platform:tps6594-pfsm"); +MODULE_AUTHOR("Julien Panis <jpanis@baylibre.com>"); +MODULE_DESCRIPTION("TPS6594 Pre-configurable Finite State Machine Driver"); +MODULE_LICENSE("GPL"); |