From cbcdec6202c934bd72fca4fe9db255d84f907dbe Mon Sep 17 00:00:00 2001 From: "Edward A. James" Date: Thu, 10 Aug 2017 16:57:48 -0500 Subject: [PATCH] hwmon: (pmbus): Access word data for STATUS_WORD Pmbus always reads byte data from the status register, even if configured to use STATUS_WORD. Use a function pointer to read the correct amount of data from the registers. Also switch to try STATUS_WORD first before STATUS_BYTE on init. Signed-off-by: Edward A. James Signed-off-by: Guenter Roeck --- drivers/hwmon/pmbus/pmbus_core.c | 54 +++++++++++++++++++++++++++++----------- 1 file changed, 40 insertions(+), 14 deletions(-) diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c index 4ec7586..277d170 100644 --- a/drivers/hwmon/pmbus/pmbus_core.c +++ b/drivers/hwmon/pmbus/pmbus_core.c @@ -113,7 +113,8 @@ struct pmbus_data { * so we keep them all together. */ u16 status[PB_NUM_STATUS_REG]; - u8 status_register; + + int (*read_status)(struct i2c_client *client, int page); u8 currpage; }; @@ -324,7 +325,7 @@ static int pmbus_check_status_cml(struct i2c_client *client) struct pmbus_data *data = i2c_get_clientdata(client); int status, status2; - status = _pmbus_read_byte_data(client, -1, data->status_register); + status = data->read_status(client, -1); if (status < 0 || (status & PB_STATUS_CML)) { status2 = _pmbus_read_byte_data(client, -1, PMBUS_STATUS_CML); if (status2 < 0 || (status2 & PB_CML_FAULT_INVALID_COMMAND)) @@ -348,6 +349,23 @@ static bool pmbus_check_register(struct i2c_client *client, return rv >= 0; } +static bool pmbus_check_status_register(struct i2c_client *client, int page) +{ + int status; + struct pmbus_data *data = i2c_get_clientdata(client); + + status = data->read_status(client, page); + if (status >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK) && + (status & PB_STATUS_CML)) { + status = _pmbus_read_byte_data(client, -1, PMBUS_STATUS_CML); + if (status < 0 || (status & PB_CML_FAULT_INVALID_COMMAND)) + status = -EIO; + } + + pmbus_clear_fault_page(client, -1); + return status >= 0; +} + bool pmbus_check_byte_register(struct i2c_client *client, int page, int reg) { return pmbus_check_register(client, _pmbus_read_byte_data, page, reg); @@ -394,8 +412,7 @@ static struct pmbus_data *pmbus_update_device(struct device *dev) for (i = 0; i < info->pages; i++) { data->status[PB_STATUS_BASE + i] - = _pmbus_read_byte_data(client, i, - data->status_register); + = data->read_status(client, i); for (j = 0; j < ARRAY_SIZE(pmbus_status); j++) { struct _pmbus_status *s = &pmbus_status[j]; @@ -1051,8 +1068,7 @@ static int pmbus_add_sensor_attrs_one(struct i2c_client *client, * the generic status register for this page is accessible. */ if (!ret && attr->gbit && - pmbus_check_byte_register(client, page, - data->status_register)) { + pmbus_check_status_register(client, page)) { ret = pmbus_add_boolean(data, name, "alarm", index, NULL, NULL, PB_STATUS_BASE + page, @@ -1729,6 +1745,16 @@ static int pmbus_identify_common(struct i2c_client *client, return 0; } +static int pmbus_read_status_byte(struct i2c_client *client, int page) +{ + return _pmbus_read_byte_data(client, page, PMBUS_STATUS_BYTE); +} + +static int pmbus_read_status_word(struct i2c_client *client, int page) +{ + return _pmbus_read_word_data(client, page, PMBUS_STATUS_WORD); +} + static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data, struct pmbus_driver_info *info) { @@ -1736,16 +1762,16 @@ static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data, int page, ret; /* - * Some PMBus chips don't support PMBUS_STATUS_BYTE, so try - * to use PMBUS_STATUS_WORD instead if that is the case. + * Some PMBus chips don't support PMBUS_STATUS_WORD, so try + * to use PMBUS_STATUS_BYTE instead if that is the case. * Bail out if both registers are not supported. */ - data->status_register = PMBUS_STATUS_BYTE; - ret = i2c_smbus_read_byte_data(client, PMBUS_STATUS_BYTE); - if (ret < 0 || ret == 0xff) { - data->status_register = PMBUS_STATUS_WORD; - ret = i2c_smbus_read_word_data(client, PMBUS_STATUS_WORD); - if (ret < 0 || ret == 0xffff) { + data->read_status = pmbus_read_status_word; + ret = i2c_smbus_read_word_data(client, PMBUS_STATUS_WORD); + if (ret < 0 || ret == 0xffff) { + data->read_status = pmbus_read_status_byte; + ret = i2c_smbus_read_byte_data(client, PMBUS_STATUS_BYTE); + if (ret < 0 || ret == 0xff) { dev_err(dev, "PMBus status register not found\n"); return -ENODEV; } -- 2.7.4