1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Driver for MPS MPQ8785 Step-Down Converter 4 */ 5 6 #include <linux/i2c.h> 7 #include <linux/bitops.h> 8 #include <linux/module.h> 9 #include <linux/property.h> 10 #include <linux/of_device.h> 11 #include "pmbus.h" 12 13 #define MPM82504_READ_TEMPERATURE_1_SIGN_POS 9 14 15 enum chips { mpm3695, mpm3695_25, mpm82504, mpq8785 }; 16 17 static u16 voltage_scale_loop_max_val[] = { 18 [mpm3695] = GENMASK(9, 0), 19 [mpm3695_25] = GENMASK(11, 0), 20 [mpm82504] = GENMASK(9, 0), 21 [mpq8785] = GENMASK(10, 0), 22 }; 23 24 static int mpq8785_identify(struct i2c_client *client, 25 struct pmbus_driver_info *info) 26 { 27 int vout_mode; 28 29 vout_mode = pmbus_read_byte_data(client, 0, PMBUS_VOUT_MODE); 30 if (vout_mode < 0 || vout_mode == 0xff) 31 return vout_mode < 0 ? vout_mode : -ENODEV; 32 switch (vout_mode >> 5) { 33 case 0: 34 info->format[PSC_VOLTAGE_OUT] = linear; 35 break; 36 case 1: 37 case 2: 38 info->format[PSC_VOLTAGE_OUT] = direct; 39 info->m[PSC_VOLTAGE_OUT] = 64; 40 info->b[PSC_VOLTAGE_OUT] = 0; 41 info->R[PSC_VOLTAGE_OUT] = 1; 42 break; 43 default: 44 return -ENODEV; 45 } 46 47 return 0; 48 }; 49 50 static int mpm82504_read_word_data(struct i2c_client *client, int page, 51 int phase, int reg) 52 { 53 int ret; 54 55 ret = pmbus_read_word_data(client, page, phase, reg); 56 57 if (ret < 0 || reg != PMBUS_READ_TEMPERATURE_1) 58 return ret; 59 60 /* Fix PMBUS_READ_TEMPERATURE_1 signedness */ 61 return sign_extend32(ret, MPM82504_READ_TEMPERATURE_1_SIGN_POS) & 0xffff; 62 } 63 64 static struct pmbus_driver_info mpq8785_info = { 65 .pages = 1, 66 .format[PSC_VOLTAGE_IN] = direct, 67 .format[PSC_CURRENT_OUT] = direct, 68 .format[PSC_TEMPERATURE] = direct, 69 .m[PSC_VOLTAGE_IN] = 4, 70 .b[PSC_VOLTAGE_IN] = 0, 71 .R[PSC_VOLTAGE_IN] = 1, 72 .m[PSC_CURRENT_OUT] = 16, 73 .b[PSC_CURRENT_OUT] = 0, 74 .R[PSC_CURRENT_OUT] = 0, 75 .m[PSC_TEMPERATURE] = 1, 76 .b[PSC_TEMPERATURE] = 0, 77 .R[PSC_TEMPERATURE] = 0, 78 .func[0] = 79 PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT | 80 PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | 81 PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | 82 PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP, 83 }; 84 85 static const struct i2c_device_id mpq8785_id[] = { 86 { "mpm3695", mpm3695 }, 87 { "mpm3695-25", mpm3695_25 }, 88 { "mpm82504", mpm82504 }, 89 { "mpq8785", mpq8785 }, 90 { }, 91 }; 92 MODULE_DEVICE_TABLE(i2c, mpq8785_id); 93 94 static const struct of_device_id __maybe_unused mpq8785_of_match[] = { 95 { .compatible = "mps,mpm3695", .data = (void *)mpm3695 }, 96 { .compatible = "mps,mpm3695-25", .data = (void *)mpm3695_25 }, 97 { .compatible = "mps,mpm82504", .data = (void *)mpm82504 }, 98 { .compatible = "mps,mpq8785", .data = (void *)mpq8785 }, 99 {} 100 }; 101 MODULE_DEVICE_TABLE(of, mpq8785_of_match); 102 103 static int mpq8785_probe(struct i2c_client *client) 104 { 105 struct device *dev = &client->dev; 106 struct pmbus_driver_info *info; 107 enum chips chip_id; 108 u32 voltage_scale; 109 int ret; 110 111 info = devm_kmemdup(dev, &mpq8785_info, sizeof(*info), GFP_KERNEL); 112 if (!info) 113 return -ENOMEM; 114 115 if (dev->of_node) 116 chip_id = (kernel_ulong_t)of_device_get_match_data(dev); 117 else 118 chip_id = (kernel_ulong_t)i2c_get_match_data(client); 119 120 switch (chip_id) { 121 case mpm3695: 122 case mpm3695_25: 123 case mpm82504: 124 info->format[PSC_VOLTAGE_OUT] = direct; 125 info->m[PSC_VOLTAGE_OUT] = 8; 126 info->b[PSC_VOLTAGE_OUT] = 0; 127 info->R[PSC_VOLTAGE_OUT] = 2; 128 info->read_word_data = mpm82504_read_word_data; 129 break; 130 case mpq8785: 131 info->identify = mpq8785_identify; 132 break; 133 default: 134 return -ENODEV; 135 } 136 137 if (!device_property_read_u32(dev, "mps,vout-fb-divider-ratio-permille", 138 &voltage_scale)) { 139 if (voltage_scale > voltage_scale_loop_max_val[chip_id]) 140 return -EINVAL; 141 142 ret = i2c_smbus_write_word_data(client, PMBUS_VOUT_SCALE_LOOP, 143 voltage_scale); 144 if (ret) 145 return ret; 146 } 147 148 return pmbus_do_probe(client, info); 149 }; 150 151 static struct i2c_driver mpq8785_driver = { 152 .driver = { 153 .name = "mpq8785", 154 .of_match_table = of_match_ptr(mpq8785_of_match), 155 }, 156 .probe = mpq8785_probe, 157 .id_table = mpq8785_id, 158 }; 159 160 module_i2c_driver(mpq8785_driver); 161 162 MODULE_AUTHOR("Charles Hsu <ythsu0511@gmail.com>"); 163 MODULE_DESCRIPTION("PMBus driver for MPS MPQ8785"); 164 MODULE_LICENSE("GPL"); 165 MODULE_IMPORT_NS("PMBUS"); 166