From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:60611 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751834AbdHHDZ5 (ORCPT ); Mon, 7 Aug 2017 23:25:57 -0400 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v783NlN3038174 for ; Mon, 7 Aug 2017 23:25:56 -0400 Received: from e15.ny.us.ibm.com (e15.ny.us.ibm.com [129.33.205.205]) by mx0b-001b2d01.pphosted.com with ESMTP id 2c71m6qe5u-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 07 Aug 2017 23:25:56 -0400 Received: from localhost by e15.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 7 Aug 2017 23:25:56 -0400 From: Eddie James To: linux@roeck-us.net Cc: linux-hwmon@vger.kernel.org, joel@jms.id.au, andrew@aj.id.au, jk@ozlabs.org, cbostic@linux.vnet.ibm.com, eajames@linux.vnet.ibm.com, "Edward A. James" Subject: [RFC 1/3] drivers/hwmon/pmbus: Access word data for STATUS_WORD and use it by default Date: Mon, 7 Aug 2017 22:25:46 -0500 In-Reply-To: <1502162748-16372-1-git-send-email-eajames@linux.vnet.ibm.com> References: <1502162748-16372-1-git-send-email-eajames@linux.vnet.ibm.com> Message-Id: <1502162748-16372-2-git-send-email-eajames@linux.vnet.ibm.com> Sender: linux-hwmon-owner@vger.kernel.org List-Id: linux-hwmon@vger.kernel.org From: "Edward A. James" Pmbus core always reads byte data from the status register, even if configured to use STATUS_WORD. Use a function pointer so we always do either byte or word access depending on which register we're trying to access. Also switch to use STATUS_WORD by default. Signed-off-by: Edward A. James --- drivers/hwmon/pmbus/pmbus_core.c | 69 +++++++++++++++++++++++++++++++--------- 1 file changed, 54 insertions(+), 15 deletions(-) diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c index f1eff6b..8511aba 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. */ u8 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 +349,36 @@ static bool pmbus_check_register(struct i2c_client *client, return rv >= 0; } +/* Check specified page status register accessibility. Need a separate + * function rather than the two above so we can use the correct status + * register, and we can optimize out the second status register read. + */ +static bool pmbus_check_status_register(struct i2c_client *client, int page) +{ + int status, rc = 0; + struct pmbus_data *data = i2c_get_clientdata(client); + + status = data->read_status(client, page); + if (status < 0) + goto out; + + if (!(data->flags & PMBUS_SKIP_STATUS_CHECK)) { + if (status & PB_STATUS_CML) { + status = _pmbus_read_byte_data(client, -1, + PMBUS_STATUS_CML); + if (status < 0 || + (status & PB_CML_FAULT_INVALID_COMMAND)) + goto out; + } + } + + rc = 1; + +out: + pmbus_clear_fault_page(client, -1); + return rc; +} + bool pmbus_check_byte_register(struct i2c_client *client, int page, int reg) { return pmbus_check_register(client, _pmbus_read_byte_data, page, reg); @@ -393,9 +424,8 @@ static struct pmbus_data *pmbus_update_device(struct device *dev) int i, j; for (i = 0; i < info->pages; i++) { - data->status[PB_STATUS_BASE + i] - = _pmbus_read_byte_data(client, i, - data->status_register); + data->status[PB_STATUS_BASE + i] = + data->read_status(client, i); for (j = 0; j < ARRAY_SIZE(pmbus_status); j++) { struct _pmbus_status *s = &pmbus_status[j]; @@ -1051,8 +1081,7 @@ 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 +1758,16 @@ static int pmbus_identify_common(struct i2c_client *client, return 0; } +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_read_status_byte(struct i2c_client *client, int page) +{ + return _pmbus_read_byte_data(client, page, PMBUS_STATUS_BYTE); +} + static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data, struct pmbus_driver_info *info) { @@ -1736,16 +1775,16 @@ 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; } -- 1.8.3.1