Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754869AbeAOMYk (ORCPT + 1 other); Mon, 15 Jan 2018 07:24:40 -0500 Received: from mail-pl0-f65.google.com ([209.85.160.65]:34178 "EHLO mail-pl0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753188AbeAOMYi (ORCPT ); Mon, 15 Jan 2018 07:24:38 -0500 X-Google-Smtp-Source: ACJfBov0xWfkgRqxdwoCvIZbMUOrrnI6SOaesSrrqOPe3LhELRiPKgDOxB0Xh9veTkEP3tgSYdd8eQ== Date: Mon, 15 Jan 2018 04:24:35 -0800 From: Guenter Roeck To: Samuel Mendoza-Jonas Cc: linux-hwmon@vger.kernel.org, Jean Delvare , linux-kernel@vger.kernel.org, OpenBMC Maillist Subject: Re: hwmon: (pmbus/ir35221) Remove unnecessary scaling Message-ID: <20180115122435.GA24640@roeck-us.net> References: <20180115055858.1188-1-sam@mendozajonas.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180115055858.1188-1-sam@mendozajonas.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: On Mon, Jan 15, 2018 at 04:58:58PM +1100, Samuel Mendoza-Jonas wrote: > The ir35221 datasheet describes specific scaling factors for a number of > commands which the current driver applies when reading. > However now that the ir35221 has been tested on machines with more > easily verifiable readings these descriptions have turned out to be > superfluous and reading each command according to the linear format is > sufficient. > > Signed-off-by: Samuel Mendoza-Jonas Applied to hwmon-next. Thanks, Guenter > --- > drivers/hwmon/pmbus/ir35221.c | 189 ------------------------------------------ > 1 file changed, 189 deletions(-) > > diff --git a/drivers/hwmon/pmbus/ir35221.c b/drivers/hwmon/pmbus/ir35221.c > index 8b906b44484b..977315b0fd90 100644 > --- a/drivers/hwmon/pmbus/ir35221.c > +++ b/drivers/hwmon/pmbus/ir35221.c > @@ -25,168 +25,19 @@ > #define IR35221_MFR_IOUT_VALLEY 0xcb > #define IR35221_MFR_TEMP_VALLEY 0xcc > > -static long ir35221_reg2data(int data, enum pmbus_sensor_classes class) > -{ > - s16 exponent; > - s32 mantissa; > - long val; > - > - /* We only modify LINEAR11 formats */ > - exponent = ((s16)data) >> 11; > - mantissa = ((s16)((data & 0x7ff) << 5)) >> 5; > - > - val = mantissa * 1000L; > - > - /* scale result to micro-units for power sensors */ > - if (class == PSC_POWER) > - val = val * 1000L; > - > - if (exponent >= 0) > - val <<= exponent; > - else > - val >>= -exponent; > - > - return val; > -} > - > -#define MAX_MANTISSA (1023 * 1000) > -#define MIN_MANTISSA (511 * 1000) > - > -static u16 ir35221_data2reg(long val, enum pmbus_sensor_classes class) > -{ > - s16 exponent = 0, mantissa; > - bool negative = false; > - > - if (val == 0) > - return 0; > - > - if (val < 0) { > - negative = true; > - val = -val; > - } > - > - /* Power is in uW. Convert to mW before converting. */ > - if (class == PSC_POWER) > - val = DIV_ROUND_CLOSEST(val, 1000L); > - > - /* Reduce large mantissa until it fits into 10 bit */ > - while (val >= MAX_MANTISSA && exponent < 15) { > - exponent++; > - val >>= 1; > - } > - /* Increase small mantissa to improve precision */ > - while (val < MIN_MANTISSA && exponent > -15) { > - exponent--; > - val <<= 1; > - } > - > - /* Convert mantissa from milli-units to units */ > - mantissa = DIV_ROUND_CLOSEST(val, 1000); > - > - /* Ensure that resulting number is within range */ > - if (mantissa > 0x3ff) > - mantissa = 0x3ff; > - > - /* restore sign */ > - if (negative) > - mantissa = -mantissa; > - > - /* Convert to 5 bit exponent, 11 bit mantissa */ > - return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800); > -} > - > -static u16 ir35221_scale_result(s16 data, int shift, > - enum pmbus_sensor_classes class) > -{ > - long val; > - > - val = ir35221_reg2data(data, class); > - > - if (shift < 0) > - val >>= -shift; > - else > - val <<= shift; > - > - return ir35221_data2reg(val, class); > -} > - > static int ir35221_read_word_data(struct i2c_client *client, int page, int reg) > { > int ret; > > switch (reg) { > - case PMBUS_IOUT_OC_FAULT_LIMIT: > - case PMBUS_IOUT_OC_WARN_LIMIT: > - ret = pmbus_read_word_data(client, page, reg); > - if (ret < 0) > - break; > - ret = ir35221_scale_result(ret, 1, PSC_CURRENT_OUT); > - break; > - case PMBUS_VIN_OV_FAULT_LIMIT: > - case PMBUS_VIN_OV_WARN_LIMIT: > - case PMBUS_VIN_UV_WARN_LIMIT: > - ret = pmbus_read_word_data(client, page, reg); > - ret = ir35221_scale_result(ret, -4, PSC_VOLTAGE_IN); > - break; > - case PMBUS_IIN_OC_WARN_LIMIT: > - ret = pmbus_read_word_data(client, page, reg); > - if (ret < 0) > - break; > - ret = ir35221_scale_result(ret, -1, PSC_CURRENT_IN); > - break; > - case PMBUS_READ_VIN: > - ret = pmbus_read_word_data(client, page, PMBUS_READ_VIN); > - if (ret < 0) > - break; > - ret = ir35221_scale_result(ret, -5, PSC_VOLTAGE_IN); > - break; > - case PMBUS_READ_IIN: > - ret = pmbus_read_word_data(client, page, PMBUS_READ_IIN); > - if (ret < 0) > - break; > - if (page == 0) > - ret = ir35221_scale_result(ret, -4, PSC_CURRENT_IN); > - else > - ret = ir35221_scale_result(ret, -5, PSC_CURRENT_IN); > - break; > - case PMBUS_READ_POUT: > - ret = pmbus_read_word_data(client, page, PMBUS_READ_POUT); > - if (ret < 0) > - break; > - ret = ir35221_scale_result(ret, -1, PSC_POWER); > - break; > - case PMBUS_READ_PIN: > - ret = pmbus_read_word_data(client, page, PMBUS_READ_PIN); > - if (ret < 0) > - break; > - ret = ir35221_scale_result(ret, -1, PSC_POWER); > - break; > - case PMBUS_READ_IOUT: > - ret = pmbus_read_word_data(client, page, PMBUS_READ_IOUT); > - if (ret < 0) > - break; > - if (page == 0) > - ret = ir35221_scale_result(ret, -1, PSC_CURRENT_OUT); > - else > - ret = ir35221_scale_result(ret, -2, PSC_CURRENT_OUT); > - break; > case PMBUS_VIRT_READ_VIN_MAX: > ret = pmbus_read_word_data(client, page, IR35221_MFR_VIN_PEAK); > - if (ret < 0) > - break; > - ret = ir35221_scale_result(ret, -5, PSC_VOLTAGE_IN); > break; > case PMBUS_VIRT_READ_VOUT_MAX: > ret = pmbus_read_word_data(client, page, IR35221_MFR_VOUT_PEAK); > break; > case PMBUS_VIRT_READ_IOUT_MAX: > ret = pmbus_read_word_data(client, page, IR35221_MFR_IOUT_PEAK); > - if (ret < 0) > - break; > - if (page == 0) > - ret = ir35221_scale_result(ret, -1, PSC_CURRENT_IN); > - else > - ret = ir35221_scale_result(ret, -2, PSC_CURRENT_IN); > break; > case PMBUS_VIRT_READ_TEMP_MAX: > ret = pmbus_read_word_data(client, page, IR35221_MFR_TEMP_PEAK); > @@ -194,9 +45,6 @@ static int ir35221_read_word_data(struct i2c_client *client, int page, int reg) > case PMBUS_VIRT_READ_VIN_MIN: > ret = pmbus_read_word_data(client, page, > IR35221_MFR_VIN_VALLEY); > - if (ret < 0) > - break; > - ret = ir35221_scale_result(ret, -5, PSC_VOLTAGE_IN); > break; > case PMBUS_VIRT_READ_VOUT_MIN: > ret = pmbus_read_word_data(client, page, > @@ -205,12 +53,6 @@ static int ir35221_read_word_data(struct i2c_client *client, int page, int reg) > case PMBUS_VIRT_READ_IOUT_MIN: > ret = pmbus_read_word_data(client, page, > IR35221_MFR_IOUT_VALLEY); > - if (ret < 0) > - break; > - if (page == 0) > - ret = ir35221_scale_result(ret, -1, PSC_CURRENT_IN); > - else > - ret = ir35221_scale_result(ret, -2, PSC_CURRENT_IN); > break; > case PMBUS_VIRT_READ_TEMP_MIN: > ret = pmbus_read_word_data(client, page, > @@ -224,36 +66,6 @@ static int ir35221_read_word_data(struct i2c_client *client, int page, int reg) > return ret; > } > > -static int ir35221_write_word_data(struct i2c_client *client, int page, int reg, > - u16 word) > -{ > - int ret; > - u16 val; > - > - switch (reg) { > - case PMBUS_IOUT_OC_FAULT_LIMIT: > - case PMBUS_IOUT_OC_WARN_LIMIT: > - val = ir35221_scale_result(word, -1, PSC_CURRENT_OUT); > - ret = pmbus_write_word_data(client, page, reg, val); > - break; > - case PMBUS_VIN_OV_FAULT_LIMIT: > - case PMBUS_VIN_OV_WARN_LIMIT: > - case PMBUS_VIN_UV_WARN_LIMIT: > - val = ir35221_scale_result(word, 4, PSC_VOLTAGE_IN); > - ret = pmbus_write_word_data(client, page, reg, val); > - break; > - case PMBUS_IIN_OC_WARN_LIMIT: > - val = ir35221_scale_result(word, 1, PSC_CURRENT_IN); > - ret = pmbus_write_word_data(client, page, reg, val); > - break; > - default: > - ret = -ENODATA; > - break; > - } > - > - return ret; > -} > - > static int ir35221_probe(struct i2c_client *client, > const struct i2c_device_id *id) > { > @@ -292,7 +104,6 @@ static int ir35221_probe(struct i2c_client *client, > if (!info) > return -ENOMEM; > > - info->write_word_data = ir35221_write_word_data; > info->read_word_data = ir35221_read_word_data; > > info->pages = 2;