diff options
| -rw-r--r-- | drivers/hwmon/pmbus/Kconfig | 1 | ||||
| -rw-r--r-- | drivers/hwmon/pmbus/adm1266.c | 78 |
2 files changed, 79 insertions, 0 deletions
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig index 890f08be7244..7902a9a72681 100644 --- a/drivers/hwmon/pmbus/Kconfig +++ b/drivers/hwmon/pmbus/Kconfig @@ -28,6 +28,7 @@ config SENSORS_PMBUS config SENSORS_ADM1266 tristate "Analog Devices ADM1266 Sequencer" + select CRC8 help If you say yes here you get hardware monitoring support for Analog Devices ADM1266 Cascadable Super Sequencer. diff --git a/drivers/hwmon/pmbus/adm1266.c b/drivers/hwmon/pmbus/adm1266.c index 9c75958c2969..d85835091a40 100644 --- a/drivers/hwmon/pmbus/adm1266.c +++ b/drivers/hwmon/pmbus/adm1266.c @@ -6,6 +6,7 @@ * Copyright 2020 Analog Devices Inc. */ +#include <linux/crc8.h> #include <linux/i2c.h> #include <linux/init.h> #include <linux/kernel.h> @@ -13,11 +14,85 @@ #include "pmbus.h" #include <linux/slab.h> +#define ADM1266_PMBUS_BLOCK_MAX 255 + struct adm1266_data { struct pmbus_driver_info info; struct i2c_client *client; + struct mutex buf_mutex; + u8 write_buf[ADM1266_PMBUS_BLOCK_MAX + 1] ____cacheline_aligned; + u8 read_buf[ADM1266_PMBUS_BLOCK_MAX + 1] ____cacheline_aligned; }; +DECLARE_CRC8_TABLE(pmbus_crc_table); + +/* + * Different from Block Read as it sends data and waits for the slave to + * return a value dependent on that data. The protocol is simply a Write Block + * followed by a Read Block without the Read-Block command field and the + * Write-Block STOP bit. + */ +static int adm1266_pmbus_block_xfer(struct adm1266_data *data, u8 cmd, u8 w_len, u8 *data_w, + u8 *data_r) +{ + struct i2c_client *client = data->client; + struct i2c_msg msgs[2] = { + { + .addr = client->addr, + .flags = I2C_M_DMA_SAFE, + .buf = data->write_buf, + .len = w_len + 2, + }, + { + .addr = client->addr, + .flags = I2C_M_RD | I2C_M_DMA_SAFE, + .buf = data->read_buf, + .len = ADM1266_PMBUS_BLOCK_MAX + 2, + } + }; + u8 addr; + u8 crc; + int ret; + + mutex_lock(&data->buf_mutex); + + msgs[0].buf[0] = cmd; + msgs[0].buf[1] = w_len; + memcpy(&msgs[0].buf[2], data_w, w_len); + + ret = i2c_transfer(client->adapter, msgs, 2); + if (ret != 2) { + if (ret >= 0) + ret = -EPROTO; + + mutex_unlock(&data->buf_mutex); + + return ret; + } + + if (client->flags & I2C_CLIENT_PEC) { + addr = i2c_8bit_addr_from_msg(&msgs[0]); + crc = crc8(pmbus_crc_table, &addr, 1, 0); + crc = crc8(pmbus_crc_table, msgs[0].buf, msgs[0].len, crc); + + addr = i2c_8bit_addr_from_msg(&msgs[1]); + crc = crc8(pmbus_crc_table, &addr, 1, crc); + crc = crc8(pmbus_crc_table, msgs[1].buf, msgs[1].buf[0] + 1, crc); + + if (crc != msgs[1].buf[msgs[1].buf[0] + 1]) { + mutex_unlock(&data->buf_mutex); + return -EBADMSG; + } + } + + memcpy(data_r, &msgs[1].buf[1], msgs[1].buf[0]); + + ret = msgs[1].buf[0]; + mutex_unlock(&data->buf_mutex); + + return ret; +} + static int adm1266_probe(struct i2c_client *client) { struct adm1266_data *data; @@ -33,6 +108,9 @@ static int adm1266_probe(struct i2c_client *client) for (i = 0; i < data->info.pages; i++) data->info.func[i] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT; + crc8_populate_msb(pmbus_crc_table, 0x7); + mutex_init(&data->buf_mutex); + return pmbus_do_probe(client, &data->info); } |