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 { } 91 }; 92 MODULE_DEVICE_TABLE(of, rn5t618_of_match); 93 94 static int rn5t618_i2c_probe(struct i2c_client *i2c, 95 const struct i2c_device_id *id) 96 { 97 const struct of_device_id *of_id; 98 struct rn5t618 *priv; 99 int ret; 100 101 of_id = of_match_device(rn5t618_of_match, &i2c->dev); 102 if (!of_id) { 103 dev_err(&i2c->dev, "Failed to find matching DT ID\n"); 104 return -EINVAL; 105 } 106 107 priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL); 108 if (!priv) 109 return -ENOMEM; 110 111 i2c_set_clientdata(i2c, priv); 112 priv->variant = (long)of_id->data; 113 114 priv->regmap = devm_regmap_init_i2c(i2c, &rn5t618_regmap_config); 115 if (IS_ERR(priv->regmap)) { 116 ret = PTR_ERR(priv->regmap); 117 dev_err(&i2c->dev, "regmap init failed: %d\n", ret); 118 return ret; 119 } 120 121 ret = devm_mfd_add_devices(&i2c->dev, -1, rn5t618_cells, 122 ARRAY_SIZE(rn5t618_cells), NULL, 0, NULL); 123 if (ret) { 124 dev_err(&i2c->dev, "failed to add sub-devices: %d\n", ret); 125 return ret; 126 } 127 128 rn5t618_pm_power_off = priv; 129 if (of_device_is_system_power_controller(i2c->dev.of_node)) { 130 if (!pm_power_off) 131 pm_power_off = rn5t618_power_off; 132 else 133 dev_warn(&i2c->dev, "Poweroff callback already assigned\n"); 134 } 135 136 rn5t618_restart_handler.notifier_call = rn5t618_restart; 137 rn5t618_restart_handler.priority = 192; 138 139 ret = register_restart_handler(&rn5t618_restart_handler); 140 if (ret) { 141 dev_err(&i2c->dev, "cannot register restart handler, %d\n", ret); 142 return ret; 143 } 144 145 return 0; 146 } 147 148 static int rn5t618_i2c_remove(struct i2c_client *i2c) 149 { 150 struct rn5t618 *priv = i2c_get_clientdata(i2c); 151 152 if (priv == rn5t618_pm_power_off) { 153 rn5t618_pm_power_off = NULL; 154 pm_power_off = NULL; 155 } 156 157 return 0; 158 } 159 160 static const struct i2c_device_id rn5t618_i2c_id[] = { 161 { } 162 }; 163 MODULE_DEVICE_TABLE(i2c, rn5t618_i2c_id); 164 165 static struct i2c_driver rn5t618_i2c_driver = { 166 .driver = { 167 .name = "rn5t618", 168 .of_match_table = of_match_ptr(rn5t618_of_match), 169 }, 170 .probe = rn5t618_i2c_probe, 171 .remove = rn5t618_i2c_remove, 172 .id_table = rn5t618_i2c_id, 173 }; 174 175 module_i2c_driver(rn5t618_i2c_driver); 176 177 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>"); 178 MODULE_DESCRIPTION("Ricoh RN5T567/618 MFD driver"); 179 MODULE_LICENSE("GPL v2"); 180