/* * Copyright (C) 2014 Gateworks Corporation, Inc. All Rights Reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include #include #include #include #include #include #include #include #include #define DRIVER_NAME "ltc3676" /* LTC3676 Registers */ #define LTC3676_BUCK1 0x01 #define LTC3676_BUCK2 0x02 #define LTC3676_BUCK3 0x03 #define LTC3676_BUCK4 0x04 #define LTC3676_LDOA 0x05 #define LTC3676_LDOB 0x06 #define LTC3676_SQD1 0x07 #define LTC3676_SQD2 0x08 #define LTC3676_CNTRL 0x09 #define LTC3676_DVB1A 0x0A #define LTC3676_DVB1B 0x0B #define LTC3676_DVB2A 0x0C #define LTC3676_DVB2B 0x0D #define LTC3676_DVB3A 0x0E #define LTC3676_DVB3B 0x0F #define LTC3676_DVB4A 0x10 #define LTC3676_DVB4B 0x11 #define LTC3676_MSKIRQ 0x12 #define LTC3676_MSKPG 0x13 #define LTC3676_USER 0x14 #define LTC3676_IRQSTAT 0x15 #define LTC3676_PGSTATL 0x16 #define LTC3676_PGSTATRT 0x17 #define LTC3676_HRST 0x1E #define LTC3676_CLIRQ 0x1F #define LTC3676_IRQSTAT_PGOOD_TIMEOUT BIT(3) #define LTC3676_IRQSTAT_UNDERVOLT_WARN BIT(4) #define LTC3676_IRQSTAT_UNDERVOLT_FAULT BIT(5) #define LTC3676_IRQSTAT_THERMAL_WARN BIT(6) #define LTC3676_IRQSTAT_THERMAL_FAULT BIT(7) enum ltc3676_reg { LTC3676_SW1, LTC3676_SW2, LTC3676_SW3, LTC3676_SW4, LTC3676_LDO1, LTC3676_LDO2, LTC3676_LDO3, LTC3676_LDO4, LTC3676_NUM_REGULATORS, }; struct ltc3676_regulator { struct regulator_desc desc; struct device_node *np; /* External feedback voltage divider */ unsigned int r1; unsigned int r2; }; struct ltc3676 { struct regmap *regmap; struct device *dev; struct ltc3676_regulator regulator_descs[LTC3676_NUM_REGULATORS]; struct regulator_dev *regulators[LTC3676_NUM_REGULATORS]; }; static int ltc3676_set_suspend_voltage(struct regulator_dev *rdev, int uV) { struct ltc3676 *ltc3676 = rdev_get_drvdata(rdev); struct device *dev = ltc3676->dev; int dcdc = rdev_get_id(rdev); int sel; dev_dbg(dev, "%s id=%d uV=%d\n", __func__, dcdc, uV); sel = regulator_map_voltage_linear(rdev, uV, uV); if (sel < 0) return sel; /* DVBB register follows right after the corresponding DVBA register */ return regmap_update_bits(ltc3676->regmap, rdev->desc->vsel_reg + 1, rdev->desc->vsel_mask, sel); } static int ltc3676_set_suspend_mode(struct regulator_dev *rdev, unsigned int mode) { struct ltc3676 *ltc3676= rdev_get_drvdata(rdev); struct device *dev = ltc3676->dev; int mask, bit = 0; int dcdc = rdev_get_id(rdev); dev_dbg(dev, "%s id=%d mode=%d\n", __func__, dcdc, mode); /* DVB reference select is bit5 of DVBA reg */ mask = 1 << 5; if (mode != REGULATOR_MODE_STANDBY) bit = mask; /* Select DVBB */ return regmap_update_bits(ltc3676->regmap, rdev->desc->vsel_reg, mask, bit); } /* SW1, SW2, SW3, SW4 linear 0.8V-3.3V with scalar via R1/R2 feeback res */ static struct regulator_ops ltc3676_linear_regulator_ops = { .enable = regulator_enable_regmap, .disable = regulator_disable_regmap, .is_enabled = regulator_is_enabled_regmap, .list_voltage = regulator_list_voltage_linear, .set_voltage_sel = regulator_set_voltage_sel_regmap, .get_voltage_sel = regulator_get_voltage_sel_regmap, .set_suspend_voltage = ltc3676_set_suspend_voltage, .set_suspend_mode = ltc3676_set_suspend_mode, }; /* always on fixed regulators */ static struct regulator_ops ltc3676_fixed_standby_regulator_ops = { }; #define LTC3676_REG(_name, _ops, en_reg, en_bit, dvba_reg, dvb_mask) \ [LTC3676_ ## _name] = { \ .desc = { \ .name = #_name, \ .n_voltages = (dvb_mask) + 1, \ .min_uV = (dvba_reg) ? 412500 : 0, \ .uV_step = (dvba_reg) ? 12500 : 0, \ .ramp_delay = (dvba_reg) ? 800 : 0, \ .fixed_uV = (dvb_mask) ? 0 : 725000, \ .ops = <c3676_ ## _ops ## _regulator_ops, \ .type = REGULATOR_VOLTAGE, \ .id = LTC3676_ ## _name, \ .owner = THIS_MODULE, \ .vsel_reg = (dvba_reg), \ .vsel_mask = (dvb_mask), \ .enable_reg = (en_reg), \ .enable_mask = (1 << en_bit), \ }, \ } #define LTC3676_LINEAR_REG(_name, _en, _dvba) \ LTC3676_REG(_name, linear, \ LTC3676_ ## _en, 7, \ LTC3676_ ## _dvba, 0x1f) #define LTC3676_FIXED_REG(_name) \ LTC3676_REG(_name, fixed_standby, 0, 0, 0, 0) static struct ltc3676_regulator ltc3676_regulators[LTC3676_NUM_REGULATORS] = { LTC3676_LINEAR_REG(SW1, BUCK1, DVB1A), LTC3676_LINEAR_REG(SW2, BUCK2, DVB2A), LTC3676_LINEAR_REG(SW3, BUCK3, DVB3A), LTC3676_LINEAR_REG(SW4, BUCK4, DVB4A), LTC3676_FIXED_REG(LDO1), LTC3676_FIXED_REG(LDO2), LTC3676_FIXED_REG(LDO3), LTC3676_FIXED_REG(LDO4), }; #ifdef CONFIG_OF static struct of_regulator_match ltc3676_matches[] = { { .name = "sw1", }, { .name = "sw2", }, { .name = "sw3", }, { .name = "sw4", }, { .name = "ldo1", }, { .name = "ldo2", }, { .name = "ldo3", }, { .name = "ldo4", }, }; static int ltc3676_parse_regulators_dt(struct ltc3676 *ltc3676) { struct device *dev = ltc3676->dev; struct device_node *node; int i, ret; node = of_find_node_by_name(dev->of_node, "regulators"); if (!node) { dev_err(dev, "regulators node not found\n"); return -EINVAL; } ret = of_regulator_match(dev, node, ltc3676_matches, ARRAY_SIZE(ltc3676_matches)); of_node_put(node); if (ret < 0) { dev_err(dev, "Error parsing regulator init data: %d\n", ret); return -EINVAL; } /* parse feedback voltage deviders: LDO3 doesn't have them */ for (i = 0; i < LTC3676_NUM_REGULATORS; i++) { struct ltc3676_regulator *rdesc = <c3676->regulator_descs[i]; struct device_node *np = ltc3676_matches[i].of_node; u32 vdiv[2]; rdesc->np = ltc3676_matches[i].of_node; if (i == LTC3676_LDO3 || !rdesc->np) continue; ret = of_property_read_u32_array(np, "lltc,fb-voltage-divider", vdiv, 2); if (ret) { dev_err(dev, "Failed to parse voltage divider: %d\n", ret); return ret; } rdesc->r1 = vdiv[0]; rdesc->r2 = vdiv[1]; } return 0; } static inline struct regulator_init_data *match_init_data(int index) { return ltc3676_matches[index].init_data; } static inline struct device_node *match_of_node(int index) { return ltc3676_matches[index].of_node; } #else static int ltc3676_parse_regulators_dt(struct ltc3676_chip *chip) { return 0; } static inline struct regulator_init_data *match_init_data(int index) { return NULL; } static inline struct device_node *match_of_node(int index) { return NULL; } #endif static bool ltc3676_writeable_reg(struct device *dev, unsigned int reg) { switch (reg) { case LTC3676_IRQSTAT: case LTC3676_BUCK1: case LTC3676_BUCK2: case LTC3676_BUCK3: case LTC3676_BUCK4: case LTC3676_LDOA: case LTC3676_LDOB: case LTC3676_SQD1: case LTC3676_SQD2: case LTC3676_CNTRL: case LTC3676_DVB1A: case LTC3676_DVB1B: case LTC3676_DVB2A: case LTC3676_DVB2B: case LTC3676_DVB3A: case LTC3676_DVB3B: case LTC3676_DVB4A: case LTC3676_DVB4B: case LTC3676_MSKIRQ: case LTC3676_MSKPG: case LTC3676_USER: case LTC3676_HRST: case LTC3676_CLIRQ: return true; } return false; } static bool ltc3676_readable_reg(struct device *dev, unsigned int reg) { switch (reg) { case LTC3676_IRQSTAT: case LTC3676_BUCK1: case LTC3676_BUCK2: case LTC3676_BUCK3: case LTC3676_BUCK4: case LTC3676_LDOA: case LTC3676_LDOB: case LTC3676_SQD1: case LTC3676_SQD2: case LTC3676_CNTRL: case LTC3676_DVB1A: case LTC3676_DVB1B: case LTC3676_DVB2A: case LTC3676_DVB2B: case LTC3676_DVB3A: case LTC3676_DVB3B: case LTC3676_DVB4A: case LTC3676_DVB4B: case LTC3676_MSKIRQ: case LTC3676_MSKPG: case LTC3676_USER: case LTC3676_HRST: case LTC3676_CLIRQ: return true; } return false; } static bool ltc3676_volatile_reg(struct device *dev, unsigned int reg) { switch (reg) { case LTC3676_IRQSTAT: case LTC3676_PGSTATL: case LTC3676_PGSTATRT: return true; } return false; } static const struct regmap_config ltc3676_regmap_config = { .reg_bits = 8, .val_bits = 8, .writeable_reg = ltc3676_writeable_reg, .readable_reg = ltc3676_readable_reg, .volatile_reg = ltc3676_volatile_reg, .max_register = LTC3676_CLIRQ, .use_single_rw = true, .cache_type = REGCACHE_RBTREE, }; static irqreturn_t ltc3676_isr(int irq, void *dev_id) { struct ltc3676 *ltc3676 = dev_id; struct device *dev = ltc3676->dev; unsigned int i, irqstat, event; regmap_read(ltc3676->regmap, LTC3676_IRQSTAT, &irqstat); dev_dbg(dev, "irq%d irqstat=0x%02x\n", irq, irqstat); if (irqstat & LTC3676_IRQSTAT_THERMAL_WARN) { dev_info(dev, "Over-temperature Warning\n"); event = REGULATOR_EVENT_OVER_TEMP; for (i = 0; i < LTC3676_NUM_REGULATORS; i++) regulator_notifier_call_chain(ltc3676->regulators[i], event, NULL); } if (irqstat & LTC3676_IRQSTAT_UNDERVOLT_WARN) { dev_info(dev, "Undervoltage Warning\n"); event = REGULATOR_EVENT_UNDER_VOLTAGE; for (i = 0; i < LTC3676_NUM_REGULATORS; i++) regulator_notifier_call_chain(ltc3676->regulators[i], event, NULL); } /* Clear warning condition */ regmap_write(ltc3676->regmap, LTC3676_CLIRQ, 0); return IRQ_HANDLED; } static inline unsigned int ltc3676_scale(unsigned int uV, u32 r1, u32 r2) { uint64_t tmp; if (uV == 0) return 0; tmp = (uint64_t)uV * r1; do_div(tmp, r2); return uV + (unsigned int)tmp; } static void ltc3676_apply_fb_voltage_divider(struct ltc3676_regulator *rdesc) { struct regulator_desc *desc = &rdesc->desc; if (!rdesc->r1 || !rdesc->r2) return; desc->min_uV = ltc3676_scale(desc->min_uV, rdesc->r1, rdesc->r2); desc->uV_step = ltc3676_scale(desc->uV_step, rdesc->r1, rdesc->r2); desc->fixed_uV = ltc3676_scale(desc->fixed_uV, rdesc->r1, rdesc->r2); } static int ltc3676_regulator_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct device *dev = &client->dev; struct ltc3676_regulator *descs; struct ltc3676 *ltc3676; int i, ret; ltc3676 = devm_kzalloc(dev, sizeof(*ltc3676), GFP_KERNEL); if (!ltc3676) return -ENOMEM; i2c_set_clientdata(client, ltc3676); ltc3676->dev = dev; descs = ltc3676->regulator_descs; memcpy(descs, ltc3676_regulators, sizeof(ltc3676_regulators)); descs[LTC3676_LDO3].desc.fixed_uV = 1800000; ltc3676->regmap = devm_regmap_init_i2c(client, <c3676_regmap_config); if (IS_ERR(ltc3676->regmap)) { ret = PTR_ERR(ltc3676->regmap); dev_err(dev, "failed to initialize regmap: %d\n", ret); return ret; } ret = ltc3676_parse_regulators_dt(ltc3676); if (ret) return ret; for (i = 0; i < LTC3676_NUM_REGULATORS; i++) { struct ltc3676_regulator *rdesc = <c3676->regulator_descs[i]; struct regulator_desc *desc = &rdesc->desc; struct regulator_init_data *init_data; struct regulator_config config = { }; init_data = match_init_data(i); if (!rdesc->np) continue; if (i != LTC3676_LDO3) { /* skip unused (defined by r1=r2=0) */ if (rdesc->r1 == 0 && rdesc->r2 == 0) continue; ltc3676_apply_fb_voltage_divider(rdesc); } config.dev = dev; config.init_data = init_data; config.driver_data = ltc3676; config.of_node = match_of_node(i); ltc3676->regulators[i] = regulator_register(desc, &config); if (IS_ERR(ltc3676->regulators[i])) { ret = PTR_ERR(ltc3676->regulators[i]); dev_err(dev, "failed to register regulator %s: %d\n", desc->name, ret); return ret; } } regmap_write(ltc3676->regmap, LTC3676_CLIRQ, 0); ret = devm_request_threaded_irq(dev, client->irq, NULL, ltc3676_isr, IRQF_TRIGGER_LOW | IRQF_ONESHOT, client->name, ltc3676); if (ret) { dev_err(dev, "Failed to request IRQ: %d\n", ret); return ret; } return 0; } static const struct i2c_device_id ltc3676_i2c_id[] = { { "ltc3676" }, { } }; MODULE_DEVICE_TABLE(i2c, ltc3676_i2c_id); static struct i2c_driver ltc3676_driver = { .driver = { .name = DRIVER_NAME, .owner = THIS_MODULE, }, .probe = ltc3676_regulator_probe, .id_table = ltc3676_i2c_id, }; module_i2c_driver(ltc3676_driver); MODULE_AUTHOR("Tim Harvey "); MODULE_DESCRIPTION("Regulator Driver for Linear Technology LTC1376"); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("i2c:ltc3676");