1 /* 2 * MFD core driver for Ricoh RN5T618 PMIC 3 * 4 * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com> 5 * Copyright (C) 2016 Toradex AG 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * version 2 as published by the Free Software Foundation. 10 * 11 * You should have received a copy of the GNU General Public License 12 * along with this program. If not, see <http://www.gnu.org/licenses/>. 13 */ 14 15 #include <linux/delay.h> 16 #include <linux/i2c.h> 17 #include <linux/mfd/core.h> 18 #include <linux/mfd/rn5t618.h> 19 #include <linux/module.h> 20 #include <linux/of_device.h> 21 #include <linux/reboot.h> 22 #include <linux/regmap.h> 23 24 static const struct mfd_cell rn5t618_cells[] = { 25 { .name = "rn5t618-regulator" }, 26 { .name = "rn5t618-wdt" }, 27 }; 28 29 static bool rn5t618_volatile_reg(struct device *dev, unsigned int reg) 30 { 31 switch (reg) { 32 case RN5T618_WATCHDOGCNT: 33 case RN5T618_DCIRQ: 34 case RN5T618_ILIMDATAH ... RN5T618_AIN0DATAL: 35 case RN5T618_IR_ADC1 ... RN5T618_IR_ADC3: 36 case RN5T618_IR_GPR: 37 case RN5T618_IR_GPF: 38 case RN5T618_MON_IOIN: 39 case RN5T618_INTMON: 40 return true; 41 default: 42 return false; 43 } 44 } 45 46 static const struct regmap_config rn5t618_regmap_config = { 47 .reg_bits = 8, 48 .val_bits = 8, 49 .volatile_reg = rn5t618_volatile_reg, 50 .max_register = RN5T618_MAX_REG, 51 .cache_type = REGCACHE_RBTREE, 52 }; 53 54 static struct rn5t618 *rn5t618_pm_power_off; 55 static struct notifier_block rn5t618_restart_handler; 56 57 static void rn5t618_trigger_poweroff_sequence(bool repower) 58 { 59 /* disable automatic repower-on */ 60 regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_REPCNT, 61 RN5T618_REPCNT_REPWRON, 62 repower ? RN5T618_REPCNT_REPWRON : 0); 63 /* start power-off sequence */ 64 regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_SLPCNT, 65 RN5T618_SLPCNT_SWPWROFF, RN5T618_SLPCNT_SWPWROFF); 66 } 67 68 static void rn5t618_power_off(void) 69 { 70 rn5t618_trigger_poweroff_sequence(false); 71 } 72 73 static int rn5t618_restart(struct notifier_block *this, 74 unsigned long mode, void *cmd) 75 { 76 rn5t618_trigger_poweroff_sequence(true); 77 78 /* 79 * Re-power factor detection on PMIC side is not instant. 1ms 80 * proved to be enough time until reset takes effect. 81 */ 82 mdelay(1); 83 84 return NOTIFY_DONE; 85 } 86 87 static const struct of_device_id rn5t618_of_match[] = { 88 { .compatible = "ricoh,rn5t567", .data = (void *)RN5T567 }, 89 { .compatible = "ricoh,rn5t618", .data = (void *)RN5T618 }, 90 { .compatible = "ricoh,rc5t619", .data = (void *)RC5T619 }, 91 { } 92 }; 93 MODULE_DEVICE_TABLE(of, rn5t618_of_match); 94 95 static int rn5t618_i2c_probe(struct i2c_client *i2c, 96 const struct i2c_device_id *id) 97 { 98 const struct of_device_id *of_id; 99 struct rn5t618 *priv; 100 int ret; 101 102 of_id = of_match_device(rn5t618_of_match, &i2c->dev); 103 if (!of_id) { 104 dev_err(&i2c->dev, "Failed to find matching DT ID\n"); 105 return -EINVAL; 106 } 107 108 priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL); 109 if (!priv) 110 return -ENOMEM; 111 112 i2c_set_clientdata(i2c, priv); 113 priv->variant = (long)of_id->data; 114 115 priv->regmap = devm_regmap_init_i2c(i2c, &rn5t618_regmap_config); 116 if (IS_ERR(priv->regmap)) { 117 ret = PTR_ERR(priv->regmap); 118 dev_err(&i2c->dev, "regmap init failed: %d\n", ret); 119 return ret; 120 } 121 122 ret = devm_mfd_add_devices(&i2c->dev, -1, rn5t618_cells, 123 ARRAY_SIZE(rn5t618_cells), NULL, 0, NULL); 124 if (ret) { 125 dev_err(&i2c->dev, "failed to add sub-devices: %d\n", ret); 126 return ret; 127 } 128 129 rn5t618_pm_power_off = priv; 130 if (of_device_is_system_power_controller(i2c->dev.of_node)) { 131 if (!pm_power_off) 132 pm_power_off = rn5t618_power_off; 133 else 134 dev_warn(&i2c->dev, "Poweroff callback already assigned\n"); 135 } 136 137 rn5t618_restart_handler.notifier_call = rn5t618_restart; 138 rn5t618_restart_handler.priority = 192; 139 140 ret = register_restart_handler(&rn5t618_restart_handler); 141 if (ret) { 142 dev_err(&i2c->dev, "cannot register restart handler, %d\n", ret); 143 return ret; 144 } 145 146 return 0; 147 } 148 149 static int rn5t618_i2c_remove(struct i2c_client *i2c) 150 { 151 struct rn5t618 *priv = i2c_get_clientdata(i2c); 152 153 if (priv == rn5t618_pm_power_off) { 154 rn5t618_pm_power_off = NULL; 155 pm_power_off = NULL; 156 } 157 158 unregister_restart_handler(&rn5t618_restart_handler); 159 160 return 0; 161 } 162 163 static const struct i2c_device_id rn5t618_i2c_id[] = { 164 { } 165 }; 166 MODULE_DEVICE_TABLE(i2c, rn5t618_i2c_id); 167 168 static struct i2c_driver rn5t618_i2c_driver = { 169 .driver = { 170 .name = "rn5t618", 171 .of_match_table = of_match_ptr(rn5t618_of_match), 172 }, 173 .probe = rn5t618_i2c_probe, 174 .remove = rn5t618_i2c_remove, 175 .id_table = rn5t618_i2c_id, 176 }; 177 178 module_i2c_driver(rn5t618_i2c_driver); 179 180 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>"); 181 MODULE_DESCRIPTION("Ricoh RN5T567/618 MFD driver"); 182 MODULE_LICENSE("GPL v2"); 183