/* * Hardware monitoring driver for ucd9200 series Digital PWM System Controllers * * Copyright (C) 2011 Ericsson AB. * * 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/err.h> #include <linux/slab.h> #include <linux/i2c.h> #include <linux/i2c/pmbus.h> #include "pmbus.h" #define UCD9200_PHASE_INFO 0xd2 #define UCD9200_DEVICE_ID 0xfd enum chips { ucd9200, ucd9220, ucd9222, ucd9224, ucd9240, ucd9244, ucd9246, ucd9248 }; static const struct i2c_device_id ucd9200_id[] = { {"ucd9200", ucd9200}, {"ucd9220", ucd9220}, {"ucd9222", ucd9222}, {"ucd9224", ucd9224}, {"ucd9240", ucd9240}, {"ucd9244", ucd9244}, {"ucd9246", ucd9246}, {"ucd9248", ucd9248}, {} }; MODULE_DEVICE_TABLE(i2c, ucd9200_id); static int ucd9200_probe(struct i2c_client *client, const struct i2c_device_id *id) { u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1]; struct pmbus_driver_info *info; const struct i2c_device_id *mid; int i, j, ret; if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_BLOCK_DATA)) return -ENODEV; ret = i2c_smbus_read_block_data(client, UCD9200_DEVICE_ID, block_buffer); if (ret < 0) { dev_err(&client->dev, "Failed to read device ID\n"); return ret; } block_buffer[ret] = '\0'; dev_info(&client->dev, "Device ID %s\n", block_buffer); for (mid = ucd9200_id; mid->name[0]; mid++) { if (!strncasecmp(mid->name, block_buffer, strlen(mid->name))) break; } if (!mid->name[0]) { dev_err(&client->dev, "Unsupported device\n"); return -ENODEV; } if (id->driver_data != ucd9200 && id->driver_data != mid->driver_data) dev_notice(&client->dev, "Device mismatch: Configured %s, detected %s\n", id->name, mid->name); info = kzalloc(sizeof(struct pmbus_driver_info), GFP_KERNEL); if (!info) return -ENOMEM; ret = i2c_smbus_read_block_data(client, UCD9200_PHASE_INFO, block_buffer); if (ret < 0) { dev_err(&client->dev, "Failed to read phase information\n"); goto out; } /* * Calculate number of configured pages (rails) from PHASE_INFO * register. * Rails have to be sequential, so we can abort after finding * the first unconfigured rail. */ info->pages = 0; for (i = 0; i < ret; i++) { if (!block_buffer[i]) break; info->pages++; } if (!info->pages) { dev_err(&client->dev, "No rails configured\n"); ret = -ENODEV; goto out; } dev_info(&client->dev, "%d rails configured\n", info->pages); /* * Set PHASE registers on all pages to 0xff to ensure that phase * specific commands will apply to all phases of a given page (rail). * This only affects the READ_IOUT and READ_TEMPERATURE2 registers. * READ_IOUT will return the sum of currents of all phases of a rail, * and READ_TEMPERATURE2 will return the maximum temperature detected * for the the phases of the rail. */ for (i = 0; i < info->pages; i++) { /* * Setting PAGE & PHASE fails once in a while for no obvious * reason, so we need to retry a couple of times. */ for (j = 0; j < 3; j++) { ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i); if (ret < 0) continue; ret = i2c_smbus_write_byte_data(client, PMBUS_PHASE, 0xff); if (ret < 0) continue; break; } if (ret < 0) { dev_err(&client->dev, "Failed to initialize PHASE registers\n"); goto out; } } if (info->pages > 1) i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0); info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_IIN | PMBUS_HAVE_PIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP; for (i = 1; i < info->pages; i++) info->func[i] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP; /* ucd9240 supports a single fan */ if (mid->driver_data == ucd9240) info->func[0] |= PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12; ret = pmbus_do_probe(client, mid, info); if (ret < 0) goto out; return 0; out: kfree(info); return ret; } static int ucd9200_remove(struct i2c_client *client) { const struct pmbus_driver_info *info; info = pmbus_get_driver_info(client); pmbus_do_remove(client); kfree(info); return 0; } /* This is the driver that will be inserted */ static struct i2c_driver ucd9200_driver = { .driver = { .name = "ucd9200", }, .probe = ucd9200_probe, .remove = ucd9200_remove, .id_table = ucd9200_id, }; static int __init ucd9200_init(void) { return i2c_add_driver(&ucd9200_driver); } static void __exit ucd9200_exit(void) { i2c_del_driver(&ucd9200_driver); } MODULE_AUTHOR("Guenter Roeck"); MODULE_DESCRIPTION("PMBus driver for TI UCD922x, UCD924x"); MODULE_LICENSE("GPL"); module_init(ucd9200_init); module_exit(ucd9200_exit);