/* * Hardware monitoring driver for ZL6100 and compatibles * * 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 #include #include #include #include #include #include #include #include "pmbus.h" enum chips { zl2004, zl2006, zl2008, zl2105, zl2106, zl6100, zl6105 }; struct zl6100_data { int id; ktime_t access; /* chip access time */ struct pmbus_driver_info info; }; #define to_zl6100_data(x) container_of(x, struct zl6100_data, info) #define ZL6100_DEVICE_ID 0xe4 #define ZL6100_WAIT_TIME 1000 /* uS */ static ushort delay = ZL6100_WAIT_TIME; module_param(delay, ushort, 0644); MODULE_PARM_DESC(delay, "Delay between chip accesses in uS"); /* Some chips need a delay between accesses */ static inline void zl6100_wait(const struct zl6100_data *data) { if (delay) { s64 delta = ktime_us_delta(ktime_get(), data->access); if (delta < delay) udelay(delay - delta); } } static int zl6100_read_word_data(struct i2c_client *client, int page, int reg) { const struct pmbus_driver_info *info = pmbus_get_driver_info(client); struct zl6100_data *data = to_zl6100_data(info); int ret; if (page || reg >= PMBUS_VIRT_BASE) return -ENXIO; zl6100_wait(data); ret = pmbus_read_word_data(client, page, reg); data->access = ktime_get(); return ret; } static int zl6100_read_byte_data(struct i2c_client *client, int page, int reg) { const struct pmbus_driver_info *info = pmbus_get_driver_info(client); struct zl6100_data *data = to_zl6100_data(info); int ret; if (page > 0) return -ENXIO; zl6100_wait(data); ret = pmbus_read_byte_data(client, page, reg); data->access = ktime_get(); return ret; } static int zl6100_write_word_data(struct i2c_client *client, int page, int reg, u16 word) { const struct pmbus_driver_info *info = pmbus_get_driver_info(client); struct zl6100_data *data = to_zl6100_data(info); int ret; if (page || reg >= PMBUS_VIRT_BASE) return -ENXIO; zl6100_wait(data); ret = pmbus_write_word_data(client, page, reg, word); data->access = ktime_get(); return ret; } static int zl6100_write_byte(struct i2c_client *client, int page, u8 value) { const struct pmbus_driver_info *info = pmbus_get_driver_info(client); struct zl6100_data *data = to_zl6100_data(info); int ret; if (page > 0) return -ENXIO; zl6100_wait(data); ret = pmbus_write_byte(client, page, value); data->access = ktime_get(); return ret; } static const struct i2c_device_id zl6100_id[] = { {"zl2004", zl2004}, {"zl2006", zl2006}, {"zl2008", zl2008}, {"zl2105", zl2105}, {"zl2106", zl2106}, {"zl6100", zl6100}, {"zl6105", zl6105}, { } }; MODULE_DEVICE_TABLE(i2c, zl6100_id); static int zl6100_probe(struct i2c_client *client, const struct i2c_device_id *id) { int ret; struct zl6100_data *data; struct pmbus_driver_info *info; u8 device_id[I2C_SMBUS_BLOCK_MAX + 1]; const struct i2c_device_id *mid; if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA | I2C_FUNC_SMBUS_READ_BLOCK_DATA)) return -ENODEV; ret = i2c_smbus_read_block_data(client, ZL6100_DEVICE_ID, device_id); if (ret < 0) { dev_err(&client->dev, "Failed to read device ID\n"); return ret; } device_id[ret] = '\0'; dev_info(&client->dev, "Device ID %s\n", device_id); mid = NULL; for (mid = zl6100_id; mid->name[0]; mid++) { if (!strncasecmp(mid->name, device_id, strlen(mid->name))) break; } if (!mid->name[0]) { dev_err(&client->dev, "Unsupported device\n"); return -ENODEV; } if (id->driver_data != mid->driver_data) dev_notice(&client->dev, "Device mismatch: Configured %s, detected %s\n", id->name, mid->name); data = kzalloc(sizeof(struct zl6100_data), GFP_KERNEL); if (!data) return -ENOMEM; data->id = mid->driver_data; /* * ZL2008, ZL2105, and ZL6100 are known to require a wait time * between I2C accesses. ZL2004 and ZL6105 are known to be safe. * * Only clear the wait time for chips known to be safe. The wait time * can be cleared later for additional chips if tests show that it * is not needed (in other words, better be safe than sorry). */ if (data->id == zl2004 || data->id == zl6105) delay = 0; /* * Since there was a direct I2C device access above, wait before * accessing the chip again. * Set the timestamp, wait, then set it again. This should provide * enough buffer time to be safe. */ data->access = ktime_get(); zl6100_wait(data); data->access = ktime_get(); info = &data->info; info->pages = 1; info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP; info->read_word_data = zl6100_read_word_data; info->read_byte_data = zl6100_read_byte_data; info->write_word_data = zl6100_write_word_data; info->write_byte = zl6100_write_byte; ret = pmbus_do_probe(client, mid, info); if (ret) goto err_mem; return 0; err_mem: kfree(data); return ret; } static int zl6100_remove(struct i2c_client *client) { const struct pmbus_driver_info *info = pmbus_get_driver_info(client); const struct zl6100_data *data = to_zl6100_data(info); pmbus_do_remove(client); kfree(data); return 0; } static struct i2c_driver zl6100_driver = { .driver = { .name = "zl6100", }, .probe = zl6100_probe, .remove = zl6100_remove, .id_table = zl6100_id, }; static int __init zl6100_init(void) { return i2c_add_driver(&zl6100_driver); } static void __exit zl6100_exit(void) { i2c_del_driver(&zl6100_driver); } MODULE_AUTHOR("Guenter Roeck"); MODULE_DESCRIPTION("PMBus driver for ZL6100 and compatibles"); MODULE_LICENSE("GPL"); module_init(zl6100_init); module_exit(zl6100_exit);