1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * MFD core driver for Ricoh RN5T618 PMIC 4 * 5 * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com> 6 * Copyright (C) 2016 Toradex AG 7 */ 8 9 #include <linux/delay.h> 10 #include <linux/i2c.h> 11 #include <linux/mfd/core.h> 12 #include <linux/mfd/rn5t618.h> 13 #include <linux/module.h> 14 #include <linux/of_device.h> 15 #include <linux/reboot.h> 16 #include <linux/regmap.h> 17 18 static const struct mfd_cell rn5t618_cells[] = { 19 { .name = "rn5t618-regulator" }, 20 { .name = "rn5t618-wdt" }, 21 }; 22 23 static bool rn5t618_volatile_reg(struct device *dev, unsigned int reg) 24 { 25 switch (reg) { 26 case RN5T618_WATCHDOGCNT: 27 case RN5T618_DCIRQ: 28 case RN5T618_ILIMDATAH ... RN5T618_AIN0DATAL: 29 case RN5T618_IR_ADC1 ... RN5T618_IR_ADC3: 30 case RN5T618_IR_GPR: 31 case RN5T618_IR_GPF: 32 case RN5T618_MON_IOIN: 33 case RN5T618_INTMON: 34 return true; 35 default: 36 return false; 37 } 38 } 39 40 static const struct regmap_config rn5t618_regmap_config = { 41 .reg_bits = 8, 42 .val_bits = 8, 43 .volatile_reg = rn5t618_volatile_reg, 44 .max_register = RN5T618_MAX_REG, 45 .cache_type = REGCACHE_RBTREE, 46 }; 47 48 static struct rn5t618 *rn5t618_pm_power_off; 49 static struct notifier_block rn5t618_restart_handler; 50 51 static void rn5t618_trigger_poweroff_sequence(bool repower) 52 { 53 /* disable automatic repower-on */ 54 regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_REPCNT, 55 RN5T618_REPCNT_REPWRON, 56 repower ? RN5T618_REPCNT_REPWRON : 0); 57 /* start power-off sequence */ 58 regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_SLPCNT, 59 RN5T618_SLPCNT_SWPWROFF, RN5T618_SLPCNT_SWPWROFF); 60 } 61 62 static void rn5t618_power_off(void) 63 { 64 rn5t618_trigger_poweroff_sequence(false); 65 } 66 67 static int rn5t618_restart(struct notifier_block *this, 68 unsigned long mode, void *cmd) 69 { 70 rn5t618_trigger_poweroff_sequence(true); 71 72 /* 73 * Re-power factor detection on PMIC side is not instant. 1ms 74 * proved to be enough time until reset takes effect. 75 */ 76 mdelay(1); 77 78 return NOTIFY_DONE; 79 } 80 81 static const struct of_device_id rn5t618_of_match[] = { 82 { .compatible = "ricoh,rn5t567", .data = (void *)RN5T567 }, 83 { .compatible = "ricoh,rn5t618", .data = (void *)RN5T618 }, 84 { .compatible = "ricoh,rc5t619", .data = (void *)RC5T619 }, 85 { } 86 }; 87 MODULE_DEVICE_TABLE(of, rn5t618_of_match); 88 89 static int rn5t618_i2c_probe(struct i2c_client *i2c, 90 const struct i2c_device_id *id) 91 { 92 const struct of_device_id *of_id; 93 struct rn5t618 *priv; 94 int ret; 95 96 of_id = of_match_device(rn5t618_of_match, &i2c->dev); 97 if (!of_id) { 98 dev_err(&i2c->dev, "Failed to find matching DT ID\n"); 99 return -EINVAL; 100 } 101 102 priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL); 103 if (!priv) 104 return -ENOMEM; 105 106 i2c_set_clientdata(i2c, priv); 107 priv->variant = (long)of_id->data; 108 109 priv->regmap = devm_regmap_init_i2c(i2c, &rn5t618_regmap_config); 110 if (IS_ERR(priv->regmap)) { 111 ret = PTR_ERR(priv->regmap); 112 dev_err(&i2c->dev, "regmap init failed: %d\n", ret); 113 return ret; 114 } 115 116 ret = devm_mfd_add_devices(&i2c->dev, -1, rn5t618_cells, 117 ARRAY_SIZE(rn5t618_cells), NULL, 0, NULL); 118 if (ret) { 119 dev_err(&i2c->dev, "failed to add sub-devices: %d\n", ret); 120 return ret; 121 } 122 123 rn5t618_pm_power_off = priv; 124 if (of_device_is_system_power_controller(i2c->dev.of_node)) { 125 if (!pm_power_off) 126 pm_power_off = rn5t618_power_off; 127 else 128 dev_warn(&i2c->dev, "Poweroff callback already assigned\n"); 129 } 130 131 rn5t618_restart_handler.notifier_call = rn5t618_restart; 132 rn5t618_restart_handler.priority = 192; 133 134 ret = register_restart_handler(&rn5t618_restart_handler); 135 if (ret) { 136 dev_err(&i2c->dev, "cannot register restart handler, %d\n", ret); 137 return ret; 138 } 139 140 return 0; 141 } 142 143 static int rn5t618_i2c_remove(struct i2c_client *i2c) 144 { 145 struct rn5t618 *priv = i2c_get_clientdata(i2c); 146 147 if (priv == rn5t618_pm_power_off) { 148 rn5t618_pm_power_off = NULL; 149 pm_power_off = NULL; 150 } 151 152 unregister_restart_handler(&rn5t618_restart_handler); 153 154 return 0; 155 } 156 157 static const struct i2c_device_id rn5t618_i2c_id[] = { 158 { } 159 }; 160 MODULE_DEVICE_TABLE(i2c, rn5t618_i2c_id); 161 162 static struct i2c_driver rn5t618_i2c_driver = { 163 .driver = { 164 .name = "rn5t618", 165 .of_match_table = of_match_ptr(rn5t618_of_match), 166 }, 167 .probe = rn5t618_i2c_probe, 168 .remove = rn5t618_i2c_remove, 169 .id_table = rn5t618_i2c_id, 170 }; 171 172 module_i2c_driver(rn5t618_i2c_driver); 173 174 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>"); 175 MODULE_DESCRIPTION("Ricoh RN5T567/618 MFD driver"); 176 MODULE_LICENSE("GPL v2"); 177