--- /dev/null
+// 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 dev_err_probe(dev, irq, "Failed to get %s irq\n",
+ pdev->resource[i].name);
+
+ 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 int tps6594_pfsm_remove(struct platform_device *pdev)
+{
+ struct tps6594_pfsm *pfsm = platform_get_drvdata(pdev);
+
+ misc_deregister(&pfsm->miscdev);
+
+ return 0;
+}
+
+static struct platform_driver tps6594_pfsm_driver = {
+ .driver = {
+ .name = "tps6594-pfsm",
+ },
+ .probe = tps6594_pfsm_probe,
+ .remove = 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");
projects / linux.git / commitdiff