Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752058Ab3IQHEN (ORCPT ); Tue, 17 Sep 2013 03:04:13 -0400 Received: from hqemgate16.nvidia.com ([216.228.121.65]:7576 "EHLO hqemgate16.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751338Ab3IQHEL (ORCPT ); Tue, 17 Sep 2013 03:04:11 -0400 X-PGP-Universal: processed; by hqnvupgp07.nvidia.com on Tue, 17 Sep 2013 00:04:09 -0700 Message-ID: <5237FEEF.9050308@nvidia.com> Date: Tue, 17 Sep 2013 15:04:15 +0800 From: Wei Ni User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130804 Thunderbird/17.0.8 MIME-Version: 1.0 To: Jean Delvare CC: "linux@roeck-us.net" , "lm-sensors@lm-sensors.org" , "linux-kernel@vger.kernel.org" , "linux-tegra@vger.kernel.org" Subject: Re: [PATCH RESEND v4] hwmon: (lm90) split set&show temp as common codes References: <1375785417-13650-1-git-send-email-wni@nvidia.com> <20130916212908.25248fae@endymion.delvare> In-Reply-To: <20130916212908.25248fae@endymion.delvare> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 11635 Lines: 319 On 09/17/2013 03:29 AM, Jean Delvare wrote: > Hi Wei, > > On Tue, 6 Aug 2013 18:36:57 +0800, Wei Ni wrote: >> Split set&show temp codes as common functions, so we can use it >> directly when implement linux thermal framework. >> And handle error return value for the lm90_select_remote_channel >> and write_tempx, then set_temp8 and set_temp11 could return it >> to user-space. >> >> Signed-off-by: Wei Ni >> --- >> drivers/hwmon/lm90.c | 150 +++++++++++++++++++++++++++++++++----------------- >> 1 file changed, 99 insertions(+), 51 deletions(-) >> >> diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c >> index cdff742..6de8e01 100644 >> --- a/drivers/hwmon/lm90.c >> +++ b/drivers/hwmon/lm90.c >> @@ -422,20 +422,29 @@ static int lm90_read16(struct i2c_client *client, u8 regh, u8 regl, u16 *value) >> * various registers have different meanings as a result of selecting a >> * non-default remote channel. >> */ >> -static inline void lm90_select_remote_channel(struct i2c_client *client, >> +static inline int lm90_select_remote_channel(struct i2c_client *client, >> struct lm90_data *data, >> int channel) >> { >> u8 config; >> + int err = 0; > > You don't have to initialize err, as you return immediately when an > error happens. You can just... Got it, I will change it. > >> >> if (data->kind == max6696) { >> lm90_read_reg(client, LM90_REG_R_CONFIG1, &config); >> config &= ~0x08; >> if (channel) >> config |= 0x08; >> - i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1, >> - config); >> + err = i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1, >> + config); >> + if (err < 0) { >> + dev_err(&client->dev, >> + "Failed to select remote channel %d, err %d\n", >> + channel, err); >> + return err; >> + } >> } >> + >> + return err; > > ... return 0 here. > >> } >> >> /* >> @@ -702,29 +711,34 @@ static u16 temp_to_u16_adt7461(struct lm90_data *data, long val) >> * Sysfs stuff >> */ >> >> -static ssize_t show_temp8(struct device *dev, struct device_attribute *devattr, >> - char *buf) >> +static int read_temp8(struct device *dev, int index) >> { >> - struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); >> struct lm90_data *data = lm90_update_device(dev); >> int temp; >> >> if (data->kind == adt7461) >> - temp = temp_from_u8_adt7461(data, data->temp8[attr->index]); >> + temp = temp_from_u8_adt7461(data, data->temp8[index]); >> else if (data->kind == max6646) >> - temp = temp_from_u8(data->temp8[attr->index]); >> + temp = temp_from_u8(data->temp8[index]); >> else >> - temp = temp_from_s8(data->temp8[attr->index]); >> + temp = temp_from_s8(data->temp8[index]); >> >> /* +16 degrees offset for temp2 for the LM99 */ >> - if (data->kind == lm99 && attr->index == 3) >> + if (data->kind == lm99 && index == 3) >> temp += 16000; >> >> - return sprintf(buf, "%d\n", temp); >> + return temp; >> } >> >> -static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr, >> - const char *buf, size_t count) >> +static ssize_t show_temp8(struct device *dev, struct device_attribute *devattr, >> + char *buf) >> +{ >> + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); >> + >> + return sprintf(buf, "%d\n", read_temp8(dev, attr->index)); >> +} >> + >> +static int write_temp8(struct device *dev, int index, long val) >> { >> static const u8 reg[8] = { >> LM90_REG_W_LOCAL_LOW, >> @@ -737,60 +751,79 @@ static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr, >> MAX6659_REG_W_REMOTE_EMERG, >> }; >> >> - struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); >> struct i2c_client *client = to_i2c_client(dev); >> struct lm90_data *data = i2c_get_clientdata(client); >> - int nr = attr->index; >> - long val; >> int err; >> >> - err = kstrtol(buf, 10, &val); >> - if (err < 0) >> - return err; >> - >> /* +16 degrees offset for temp2 for the LM99 */ >> - if (data->kind == lm99 && attr->index == 3) >> + if (data->kind == lm99 && index == 3) >> val -= 16000; >> >> mutex_lock(&data->update_lock); >> if (data->kind == adt7461) >> - data->temp8[nr] = temp_to_u8_adt7461(data, val); >> + data->temp8[index] = temp_to_u8_adt7461(data, val); >> else if (data->kind == max6646) >> - data->temp8[nr] = temp_to_u8(val); >> + data->temp8[index] = temp_to_u8(val); >> else >> - data->temp8[nr] = temp_to_s8(val); >> - >> - lm90_select_remote_channel(client, data, nr >= 6); >> - i2c_smbus_write_byte_data(client, reg[nr], data->temp8[nr]); >> - lm90_select_remote_channel(client, data, 0); >> + data->temp8[index] = temp_to_s8(val); >> >> + err = lm90_select_remote_channel(client, data, index >= 6); >> + err |= i2c_smbus_write_byte_data(client, reg[index], data->temp8[index]); >> + err |= lm90_select_remote_channel(client, data, 0); > > You can't use |= for error codes. Imagine that > lm90_select_remote_channel() returns -EIO (-5) and > i2c_smbus_write_byte_data() returns -EAGAIN (-11), err will have value > -EPERM (-1) which makes no sense. You have to report errors as soon as > they happen so that the error code isn't lost. > > What you can do is: > > if ((err = f1(...)) || > (err = f2(...)) || > (err = f3(...))) { > dev_err(...); > return err; > } > > I think checkpatch will complain about that construct but me, I'm fine > with it. Ok, I will do it. > >> + if (err) >> + dev_err(dev, "write_temp8 failed!\n"); >> mutex_unlock(&data->update_lock); >> + >> + return err; >> +} >> + >> +static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr, >> + const char *buf, size_t count) >> +{ >> + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); >> + int index = attr->index; >> + long val; >> + int err; >> + >> + err = kstrtol(buf, 10, &val); >> + if (err < 0) >> + return err; >> + >> + err = write_temp8(dev, index, val); >> + if (err < 0) >> + return err; >> + >> return count; >> } >> >> -static ssize_t show_temp11(struct device *dev, struct device_attribute *devattr, >> - char *buf) >> +static int read_temp11(struct device *dev, int index) >> { >> - struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr); >> struct lm90_data *data = lm90_update_device(dev); >> int temp; >> >> if (data->kind == adt7461) >> - temp = temp_from_u16_adt7461(data, data->temp11[attr->index]); >> + temp = temp_from_u16_adt7461(data, data->temp11[index]); >> else if (data->kind == max6646) >> - temp = temp_from_u16(data->temp11[attr->index]); >> + temp = temp_from_u16(data->temp11[index]); >> else >> - temp = temp_from_s16(data->temp11[attr->index]); >> + temp = temp_from_s16(data->temp11[index]); >> >> /* +16 degrees offset for temp2 for the LM99 */ >> - if (data->kind == lm99 && attr->index <= 2) >> + if (data->kind == lm99 && index <= 2) >> temp += 16000; >> >> - return sprintf(buf, "%d\n", temp); >> + return temp; >> } >> >> -static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr, >> - const char *buf, size_t count) >> +static ssize_t show_temp11(struct device *dev, struct device_attribute *devattr, >> + char *buf) >> +{ >> + struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr); >> + >> + return sprintf(buf, "%d\n", read_temp11(dev, attr->index)); >> +} >> + >> +static int write_temp11(struct device *dev, int nr, int index, long val) >> { >> struct { >> u8 high; >> @@ -804,18 +837,10 @@ static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr, >> { LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL, 1 } >> }; >> >> - struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr); >> struct i2c_client *client = to_i2c_client(dev); >> struct lm90_data *data = i2c_get_clientdata(client); >> - int nr = attr->nr; >> - int index = attr->index; >> - long val; >> int err; >> >> - err = kstrtol(buf, 10, &val); >> - if (err < 0) >> - return err; >> - >> /* +16 degrees offset for temp2 for the LM99 */ >> if (data->kind == lm99 && index <= 2) >> val -= 16000; >> @@ -830,15 +855,38 @@ static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr, >> else >> data->temp11[index] = temp_to_s8(val) << 8; >> >> - lm90_select_remote_channel(client, data, reg[nr].channel); >> - i2c_smbus_write_byte_data(client, reg[nr].high, >> + err = lm90_select_remote_channel(client, data, reg[nr].channel); >> + err |= i2c_smbus_write_byte_data(client, reg[nr].high, >> data->temp11[index] >> 8); >> if (data->flags & LM90_HAVE_REM_LIMIT_EXT) >> - i2c_smbus_write_byte_data(client, reg[nr].low, >> - data->temp11[index] & 0xff); >> - lm90_select_remote_channel(client, data, 0); >> + err |= i2c_smbus_write_byte_data(client, reg[nr].low, >> + data->temp11[index] & 0xff); >> + err |= lm90_select_remote_channel(client, data, 0); >> + if (err) >> + dev_err(dev, "write_temp11 failed !\n"); > > Same here, you can't use |=. > > Also, no space needed before exclamation marks in English. Oh, you reviewed so carefully, thanks. > >> >> mutex_unlock(&data->update_lock); >> + >> + return err; >> +} >> + >> +static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr, >> + const char *buf, size_t count) >> +{ >> + struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr); >> + int nr = attr->nr; >> + int index = attr->index; >> + long val; >> + int err; >> + >> + err = kstrtol(buf, 10, &val); >> + if (err < 0) >> + return err; >> + >> + err = write_temp11(dev, nr, index, val); >> + if (err < 0) >> + return err; >> + >> return count; >> } >> > > -- > Jean Delvare > -- > To unsubscribe from this list: send the line "unsubscribe linux-tegra" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/