From: Lars-Peter Clausen <lars@metafoo.de>
To: "Luck, Tony" <tony.luck@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
linux-kernel@vger.kernel.org, Bill Pemberton <wfp5p@virginia.edu>,
Joe Perches <joe@perches.com>, Jonathan Cameron <jic23@cam.ac.uk>,
Jonathan Cameron <jic23@kernel.org>,
Paul Gortmaker <paul.gortmaker@windriver.com>,
Sonic Zhang <sonic.zhang@analog.com>
Subject: Re: [PATCH] staging/adt7316 Fix some 'interesting' string operations
Date: Sat, 06 Apr 2013 12:08:56 +0200 [thread overview]
Message-ID: <515FF438.6090305@metafoo.de> (raw)
In-Reply-To: <515df29417437372eb@agluck-desk.sc.intel.com>
On 04/04/2013 11:37 PM, Luck, Tony wrote:
> Calling memcmp() to check the value of the first byte in a string is overkill.
> Just use buf[0] == '1' or buf[0] != '1' as appropriate.
>
> Signed-off-by: Tony Luck <tony.luck@intel.com>
>
I think it is a good idea to switch directly to strtobool. But anyway, if you
don't want to respin the patch it is fine as it is.
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
> ---
>
> [Inspired by a rant on IRC about a different driver doing something similar]
>
> diff --git a/drivers/staging/iio/addac/adt7316.c b/drivers/staging/iio/addac/adt7316.c
> index 0b431bc..506b5a7 100644
> --- a/drivers/staging/iio/addac/adt7316.c
> +++ b/drivers/staging/iio/addac/adt7316.c
> @@ -256,7 +256,7 @@ static ssize_t adt7316_store_enabled(struct device *dev,
> struct adt7316_chip_info *chip = iio_priv(dev_info);
> int enable;
>
> - if (!memcmp(buf, "1", 1))
> + if (buf[0] == '1')
> enable = 1;
> else
> enable = 0;
> @@ -299,7 +299,7 @@ static ssize_t adt7316_store_select_ex_temp(struct device *dev,
> return -EPERM;
>
> config1 = chip->config1 & (~ADT7516_SEL_EX_TEMP);
> - if (!memcmp(buf, "1", 1))
> + if (buf[0] == '1')
> config1 |= ADT7516_SEL_EX_TEMP;
>
> ret = chip->bus.write(chip->bus.client, ADT7316_CONFIG1, config1);
> @@ -495,7 +495,7 @@ static ssize_t adt7316_store_disable_averaging(struct device *dev,
> int ret;
>
> config2 = chip->config2 & (~ADT7316_DISABLE_AVERAGING);
> - if (!memcmp(buf, "1", 1))
> + if (buf[0] == '1')
> config2 |= ADT7316_DISABLE_AVERAGING;
>
> ret = chip->bus.write(chip->bus.client, ADT7316_CONFIG2, config2);
> @@ -534,7 +534,7 @@ static ssize_t adt7316_store_enable_smbus_timeout(struct device *dev,
> int ret;
>
> config2 = chip->config2 & (~ADT7316_EN_SMBUS_TIMEOUT);
> - if (!memcmp(buf, "1", 1))
> + if (buf[0] == '1')
> config2 |= ADT7316_EN_SMBUS_TIMEOUT;
>
> ret = chip->bus.write(chip->bus.client, ADT7316_CONFIG2, config2);
> @@ -597,7 +597,7 @@ static ssize_t adt7316_store_powerdown(struct device *dev,
> int ret;
>
> config1 = chip->config1 & (~ADT7316_PD);
> - if (!memcmp(buf, "1", 1))
> + if (buf[0] == '1')
> config1 |= ADT7316_PD;
>
> ret = chip->bus.write(chip->bus.client, ADT7316_CONFIG1, config1);
> @@ -635,7 +635,7 @@ static ssize_t adt7316_store_fast_ad_clock(struct device *dev,
> int ret;
>
> config3 = chip->config3 & (~ADT7316_ADCLK_22_5);
> - if (!memcmp(buf, "1", 1))
> + if (buf[0] == '1')
> config3 |= ADT7316_ADCLK_22_5;
>
> ret = chip->bus.write(chip->bus.client, ADT7316_CONFIG3, config3);
> @@ -681,7 +681,7 @@ static ssize_t adt7316_store_da_high_resolution(struct device *dev,
>
> chip->dac_bits = 8;
>
> - if (!memcmp(buf, "1", 1)) {
> + if (buf[0] == '1') {
> config3 = chip->config3 | ADT7316_DA_HIGH_RESOLUTION;
> if (chip->id == ID_ADT7316 || chip->id == ID_ADT7516)
> chip->dac_bits = 12;
> @@ -731,7 +731,7 @@ static ssize_t adt7316_store_AIN_internal_Vref(struct device *dev,
> if ((chip->id & ID_FAMILY_MASK) != ID_ADT75XX)
> return -EPERM;
>
> - if (memcmp(buf, "1", 1))
> + if (buf[0] != '1')
> config3 = chip->config3 & (~ADT7516_AIN_IN_VREF);
> else
> config3 = chip->config3 | ADT7516_AIN_IN_VREF;
> @@ -773,7 +773,7 @@ static ssize_t adt7316_store_enable_prop_DACA(struct device *dev,
> int ret;
>
> config3 = chip->config3 & (~ADT7316_EN_IN_TEMP_PROP_DACA);
> - if (!memcmp(buf, "1", 1))
> + if (buf[0] == '1')
> config3 |= ADT7316_EN_IN_TEMP_PROP_DACA;
>
> ret = chip->bus.write(chip->bus.client, ADT7316_CONFIG3, config3);
> @@ -812,7 +812,7 @@ static ssize_t adt7316_store_enable_prop_DACB(struct device *dev,
> int ret;
>
> config3 = chip->config3 & (~ADT7316_EN_EX_TEMP_PROP_DACB);
> - if (!memcmp(buf, "1", 1))
> + if (buf[0] == '1')
> config3 |= ADT7316_EN_EX_TEMP_PROP_DACB;
>
> ret = chip->bus.write(chip->bus.client, ADT7316_CONFIG3, config3);
> @@ -1018,7 +1018,7 @@ static ssize_t adt7316_store_DA_AB_Vref_bypass(struct device *dev,
> return -EPERM;
>
> dac_config = chip->dac_config & (~ADT7316_VREF_BYPASS_DAC_AB);
> - if (!memcmp(buf, "1", 1))
> + if (buf[0] == '1')
> dac_config |= ADT7316_VREF_BYPASS_DAC_AB;
>
> ret = chip->bus.write(chip->bus.client, ADT7316_DAC_CONFIG, dac_config);
> @@ -1063,7 +1063,7 @@ static ssize_t adt7316_store_DA_CD_Vref_bypass(struct device *dev,
> return -EPERM;
>
> dac_config = chip->dac_config & (~ADT7316_VREF_BYPASS_DAC_CD);
> - if (!memcmp(buf, "1", 1))
> + if (buf[0] == '1')
> dac_config |= ADT7316_VREF_BYPASS_DAC_CD;
>
> ret = chip->bus.write(chip->bus.client, ADT7316_DAC_CONFIG, dac_config);
> @@ -1982,7 +1982,7 @@ static ssize_t adt7316_set_int_enabled(struct device *dev,
> int ret;
>
> config1 = chip->config1 & (~ADT7316_INT_EN);
> - if (!memcmp(buf, "1", 1))
> + if (buf[0] == '1')
> config1 |= ADT7316_INT_EN;
>
> ret = chip->bus.write(chip->bus.client, ADT7316_CONFIG1, config1);
> --
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next prev parent reply other threads:[~2013-04-06 10:06 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-04 21:37 [PATCH] staging/adt7316 Fix some 'interesting' string operations Luck, Tony
2013-04-05 22:03 ` Greg Kroah-Hartman
2013-04-06 10:08 ` Lars-Peter Clausen [this message]
2013-04-08 17:54 ` Luck, Tony
2013-04-09 17:11 ` Jonathan Cameron
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