drivers/misc/tps6594-pfsm.c - linux - Git at Google

 // 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");
	// 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");