SPI driver for analog to digital converters national semiconductor ADC081S101,
ADC124S501, ...
Signed-off-by: Marc Pignat <[email protected]>
Hi all!
patch against 2.6.26, tested on a custom arm board and only compil-tested on
x86.
This driver add support for National Semiconductor ADC<bb><c>S<sss> chip family,
where:
* bb is the resolution in number of bits (8, 10, 12)
* c is the number of channels (1, 2, 4)
* sss is the maximum conversion speed (021 for 200 kSPS, 051 for 500
kSPS and 101 for 1 MSPS)
Some remarks:
* The chip type (-> the number of inputs) are determined by the module alias,
is it a good idea? it could be implemented using platform data.
* The Makefile seems ordered alphabetically, what order should be used for
the Konfig file?
Best regards
Marc
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 00ff533..9c4a579 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -390,6 +390,22 @@ config SENSORS_LM70
This driver can also be built as a module. If so, the module
will be called lm70.
+config SENSORS_ADCXX
+ tristate "National Semiconductor ADCxxxSxxx"
+ depends on SPI_MASTER && EXPERIMENTAL
+ help
+ If you say yes here you get support for the National Semiconductor
+ ADC<bb><c>S<sss> chip family, where
+ * bb is the resolution in number of bits (8, 10, 12)
+ * c is the number of channels (1, 2, 4)
+ * sss is the maximum conversion speed (021 for 200 kSPS, 051 for 500
+ kSPS and 101 for 1 MSPS)
+
+ Examples : ADC081S101, ADC124S501, ...
+
+ This driver can also be built as a module. If so, the module
+ will be called adcxx.
+
config SENSORS_LM75
tristate "National Semiconductor LM75 and compatibles"
depends on I2C
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index d098677..026ba1e 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_SENSORS_W83791D) += w83791d.o
obj-$(CONFIG_SENSORS_ABITUGURU) += abituguru.o
obj-$(CONFIG_SENSORS_ABITUGURU3)+= abituguru3.o
obj-$(CONFIG_SENSORS_AD7418) += ad7418.o
+obj-$(CONFIG_SENSORS_ADCXX) += adcxx.o
obj-$(CONFIG_SENSORS_ADM1021) += adm1021.o
obj-$(CONFIG_SENSORS_ADM1025) += adm1025.o
obj-$(CONFIG_SENSORS_ADM1026) += adm1026.o
diff --git a/drivers/hwmon/adcxx.c b/drivers/hwmon/adcxx.c
new file mode 100644
index 0000000..d920fe5
--- /dev/null
+++ b/drivers/hwmon/adcxx.c
@@ -0,0 +1,292 @@
+/*
+ * adcxx.c
+ *
+ * The adcxx4s is an AD converter family from National Semiconductor (NS).
+ *
+ * Copyright (c) 2008 Marc Pignat <[email protected]>
+ *
+ * The adcxx4s communicates with a host processor via an SPI/Microwire Bus
+ * interface. This driver supports the whole family of devices with name
+ * ADC<bb><c>S<sss>, where
+ * * bb is the resolution in number of bits (8, 10, 12)
+ * * c is the number of channels (1, 2, 4)
+ * * sss is the maximum conversion speed (021 for 200 kSPS, 051 for 500 kSPS
+ * and 101 for 1 MSPS)
+ *
+ * Complete datasheets are available at National's website here:
+ * http://www.national.com/ds/DC/ADC<bb><c>S<sss>.pdf
+ *
+ * Handling of 8, 10 and 12 bits converters are the same, the
+ * unavailable bits are 0 :)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/sysfs.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/mutex.h>
+#include <linux/spi/spi.h>
+
+#define DRVNAME "adcxx"
+
+struct adcxx {
+ struct device *hwmon_dev;
+ struct mutex lock;
+ u32 channels;
+ u32 reference; /* in millivolts */
+};
+
+/* sysfs hook function */
+static ssize_t adcxx_read(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ struct adcxx *adc = dev_get_drvdata(&spi->dev);
+
+ u8 tx_buf[2] = { attr->index << 3 }; /* other bits are don't care */
+ u8 rx_buf[2];
+ int status;
+ int value;
+
+ if (mutex_lock_interruptible(&adc->lock))
+ return -ERESTARTSYS;
+
+ status = spi_write_then_read(spi, tx_buf, sizeof(tx_buf),
+ rx_buf, sizeof(rx_buf));
+ if (status < 0) {
+ dev_warn(dev, "spi_write_then_read failed with status %d\n",
+ status);
+ goto out;
+ }
+
+ value = (rx_buf[0] << 8) + rx_buf[1];
+ dev_dbg(dev, "raw value = 0x%x\n", value);
+
+ value = value * adc->reference >> 12;
+ status = sprintf(buf, "%d\n", value);
+out:
+ mutex_unlock(&adc->lock);
+ return status;
+}
+
+static ssize_t adcxx_show_min(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ /* The minimum reference is 0 for this chip family */
+ return sprintf(buf, "0\n");
+}
+
+static ssize_t adcxx_show_max(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct adcxx *adc = dev_get_drvdata(&spi->dev);
+
+ u32 reference;
+
+ if (mutex_lock_interruptible(&adc->lock))
+ return -ERESTARTSYS;
+
+ reference = adc->reference;
+
+ mutex_unlock(&adc->lock);
+
+ return sprintf(buf, "%d\n", reference);
+}
+
+static ssize_t adcxx_set_max(struct device *dev,
+ struct device_attribute *devattr, const char *buf, size_t count)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct adcxx *adc = dev_get_drvdata(&spi->dev);
+
+ unsigned long value;
+
+ if (strict_strtoul(buf, 10, &value))
+ return -EINVAL;
+
+ if (mutex_lock_interruptible(&adc->lock))
+ return -ERESTARTSYS;
+
+ adc->reference = value;
+
+ mutex_unlock(&adc->lock);
+
+ return count;
+}
+
+static ssize_t adcxx_show_name(struct device *dev, struct device_attribute
+ *devattr, char *buf)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct adcxx *adc = dev_get_drvdata(&spi->dev);
+
+ return sprintf(buf, "adcxx%ds\n", adc->channels);
+}
+
+static struct sensor_device_attribute ad_input[] = {
+ SENSOR_ATTR(name, S_IRUGO, adcxx_show_name, NULL, 0),
+
+ /* The reference is the same for all channels */
+ SENSOR_ATTR(in_min, S_IRUGO, adcxx_show_min, NULL, 0),
+ SENSOR_ATTR(in_max, S_IWUSR | S_IRUGO, adcxx_show_max,
+ adcxx_set_max, 0),
+
+ SENSOR_ATTR(in0_input, S_IRUGO, adcxx_read, NULL, 0),
+ SENSOR_ATTR(in1_input, S_IRUGO, adcxx_read, NULL, 1),
+ SENSOR_ATTR(in2_input, S_IRUGO, adcxx_read, NULL, 2),
+ SENSOR_ATTR(in3_input, S_IRUGO, adcxx_read, NULL, 3),
+};
+
+/*----------------------------------------------------------------------*/
+
+static int __devinit adcxx_probe(struct spi_device *spi, int channels)
+{
+ struct adcxx *adc;
+ int status;
+ int i;
+
+ adc = kzalloc(sizeof *adc, GFP_KERNEL);
+ if (!adc)
+ return -ENOMEM;
+
+ /* set a default value for the reference */
+ adc->reference = 3300;
+
+ adc->channels = channels;
+
+ mutex_init(&adc->lock);
+
+ dev_set_drvdata(&spi->dev, adc);
+
+ for (i = 0; i < 3 + adc->channels; i++) {
+ status = device_create_file(&spi->dev, &ad_input[i].dev_attr);
+ if (status)
+ goto out_dev_create_file_failed;
+ }
+
+ adc->hwmon_dev = hwmon_device_register(&spi->dev);
+ if (IS_ERR(adc->hwmon_dev)) {
+ dev_dbg(&spi->dev, "hwmon_device_register failed.\n");
+ status = PTR_ERR(adc->hwmon_dev);
+ goto out_dev_reg_failed;
+ }
+
+ return 0;
+
+out_dev_create_file_failed:
+ hwmon_device_unregister(adc->hwmon_dev);
+ for (i = 0; i < 3 + adc->channels; i++)
+ device_remove_file(&spi->dev, &ad_input[i].dev_attr);
+out_dev_reg_failed:
+ dev_set_drvdata(&spi->dev, NULL);
+ kfree(adc);
+ return status;
+}
+
+static int __devinit adcxx1s_probe(struct spi_device *spi)
+{
+ return adcxx_probe(spi, 1);
+}
+
+static int __devinit adcxx2s_probe(struct spi_device *spi)
+{
+ return adcxx_probe(spi, 2);
+}
+
+static int __devinit adcxx4s_probe(struct spi_device *spi)
+{
+ return adcxx_probe(spi, 4);
+}
+
+static int __devexit adcxx_remove(struct spi_device *spi)
+{
+ struct adcxx *adc = dev_get_drvdata(&spi->dev);
+ int i;
+
+ hwmon_device_unregister(adc->hwmon_dev);
+ for (i = 0; i < 3 + adc->channels; i++)
+ device_remove_file(&spi->dev, &ad_input[i].dev_attr);
+ dev_set_drvdata(&spi->dev, NULL);
+ kfree(adc);
+
+ return 0;
+}
+
+static struct spi_driver adcxx1s_driver = {
+ .driver = {
+ .name = "adcxx1s",
+ .owner = THIS_MODULE,
+ },
+ .probe = adcxx1s_probe,
+ .remove = __devexit_p(adcxx_remove),
+};
+
+static struct spi_driver adcxx2s_driver = {
+ .driver = {
+ .name = "adcxx2s",
+ .owner = THIS_MODULE,
+ },
+ .probe = adcxx2s_probe,
+ .remove = __devexit_p(adcxx_remove),
+};
+
+static struct spi_driver adcxx4s_driver = {
+ .driver = {
+ .name = "adcxx4s",
+ .owner = THIS_MODULE,
+ },
+ .probe = adcxx4s_probe,
+ .remove = __devexit_p(adcxx_remove),
+};
+
+static int __init init_adcxx(void)
+{
+ int status;
+ status = spi_register_driver(&adcxx1s_driver);
+ if (status)
+ return status;
+
+ status = spi_register_driver(&adcxx2s_driver);
+ if (status)
+ return status;
+
+ return spi_register_driver(&adcxx4s_driver);
+}
+
+static void __exit exit_adcxx(void)
+{
+ spi_unregister_driver(&adcxx1s_driver);
+ spi_unregister_driver(&adcxx2s_driver);
+ spi_unregister_driver(&adcxx4s_driver);
+}
+
+module_init(init_adcxx);
+module_exit(exit_adcxx);
+
+MODULE_AUTHOR("Marc Pignat");
+MODULE_DESCRIPTION("National Semiconductor adcxx4sxxx Linux driver");
+MODULE_LICENSE("GPL");
+
+MODULE_ALIAS("adcxx1s");
+MODULE_ALIAS("adcxx2s");
+MODULE_ALIAS("adcxx4s");
Hi Marc,
I just wrote a similar driver for the ADC088S052.
Yesterday I noticed your patch and successfully tested a slightly
modified version of it that supports 8 channels.
The patch below goes on top of yours.
Bye
Tobias
Signed-off-by: Tobias Himmer <[email protected]>
---
Index: linux-2.6.26-rc/drivers/hwmon/adcxx.c
===================================================================
--- linux-2.6.26-rc.orig/drivers/hwmon/adcxx.c
+++ linux-2.6.26-rc/drivers/hwmon/adcxx.c
@@ -5,13 +5,15 @@
*
* Copyright (c) 2008 Marc Pignat <[email protected]>
*
+ * 8 channel support added by Tobias Himmer <[email protected]>
+ *
* The adcxx4s communicates with a host processor via an SPI/Microwire Bus
* interface. This driver supports the whole family of devices with name
* ADC<bb><c>S<sss>, where
* * bb is the resolution in number of bits (8, 10, 12)
- * * c is the number of channels (1, 2, 4)
- * * sss is the maximum conversion speed (021 for 200 kSPS, 051 for 500 kSPS
- * and 101 for 1 MSPS)
+ * * c is the number of channels (1, 2, 4, 8)
+ * * sss is the maximum conversion speed (021 for 200 kSPS, 051 / 052 for
+ * 500 kSPS and 101 for 1 MSPS)
*
* Complete datasheets are available at National's website here:
* http://www.national.com/ds/DC/ADC<bb><c>S<sss>.pdf
@@ -155,6 +157,10 @@ static struct sensor_device_attribute ad
SENSOR_ATTR(in1_input, S_IRUGO, adcxx_read, NULL, 1),
SENSOR_ATTR(in2_input, S_IRUGO, adcxx_read, NULL, 2),
SENSOR_ATTR(in3_input, S_IRUGO, adcxx_read, NULL, 3),
+ SENSOR_ATTR(in4_input, S_IRUGO, adcxx_read, NULL, 4),
+ SENSOR_ATTR(in5_input, S_IRUGO, adcxx_read, NULL, 5),
+ SENSOR_ATTR(in6_input, S_IRUGO, adcxx_read, NULL, 6),
+ SENSOR_ATTR(in7_input, S_IRUGO, adcxx_read, NULL, 7),
};
/*----------------------------------------------------------------------*/
@@ -218,6 +224,11 @@ static int __devinit adcxx4s_probe(struc
return adcxx_probe(spi, 4);
}
+static int __devinit adcxx8s_probe(struct spi_device *spi)
+{
+ return adcxx_probe(spi, 8);
+}
+
static int __devexit adcxx_remove(struct spi_device *spi)
{
struct adcxx *adc = dev_get_drvdata(&spi->dev);
@@ -259,6 +270,15 @@ static struct spi_driver adcxx4s_driver
.remove = __devexit_p(adcxx_remove),
};
+static struct spi_driver adcxx8s_driver = {
+ .driver = {
+ .name = "adcxx8s",
+ .owner = THIS_MODULE,
+ },
+ .probe = adcxx8s_probe,
+ .remove = __devexit_p(adcxx_remove),
+};
+
static int __init init_adcxx(void)
{
int status;
@@ -270,7 +290,11 @@ static int __init init_adcxx(void)
if (status)
return status;
- return spi_register_driver(&adcxx4s_driver);
+ status = spi_register_driver(&adcxx4s_driver);
+ if (status)
+ return status;
+
+ return spi_register_driver(&adcxx8s_driver);
}
static void __exit exit_adcxx(void)
@@ -278,6 +302,7 @@ static void __exit exit_adcxx(void)
spi_unregister_driver(&adcxx1s_driver);
spi_unregister_driver(&adcxx2s_driver);
spi_unregister_driver(&adcxx4s_driver);
+ spi_unregister_driver(&adcxx8s_driver);
}
module_init(init_adcxx);
@@ -290,3 +315,4 @@ MODULE_LICENSE("GPL");
MODULE_ALIAS("adcxx1s");
MODULE_ALIAS("adcxx2s");
MODULE_ALIAS("adcxx4s");
+MODULE_ALIAS("adcxx8s");
Index: linux-2.6.26-rc/drivers/hwmon/Kconfig
===================================================================
--- linux-2.6.26-rc.orig/drivers/hwmon/Kconfig
+++ linux-2.6.26-rc/drivers/hwmon/Kconfig
@@ -397,9 +397,9 @@ config SENSORS_ADCXX
If you say yes here you get support for the National Semiconductor
ADC<bb><c>S<sss> chip family, where
* bb is the resolution in number of bits (8, 10, 12)
- * c is the number of channels (1, 2, 4)
- * sss is the maximum conversion speed (021 for 200 kSPS, 051 for 500
- kSPS and 101 for 1 MSPS)
+ * c is the number of channels (1, 2, 4, 8)
+ * sss is the maximum conversion speed (021 for 200 kSPS, 051 / 052 for
+ 500 kSPS and 101 for 1 MSPS)
Examples : ADC081S101, ADC124S501, ...
On Thu, Jul 24, 2008 at 11:51:50AM +0200, Tobias Himmer wrote:
> Hi Marc,
>
> I just wrote a similar driver for the ADC088S052.
Bad luck ;-)
> Yesterday I noticed your patch and successfully tested a slightly
> modified version of it that supports 8 channels.
> The patch below goes on top of yours.
Nice, both patches combined in mainline would be nice. Works for me.
Thanks,
Hans
>
> Bye
>
> Tobias
>
> Signed-off-by: Tobias Himmer <[email protected]>
Acked-by: Hans J. Koch <[email protected]>
> ---
>
> Index: linux-2.6.26-rc/drivers/hwmon/adcxx.c
> ===================================================================
> --- linux-2.6.26-rc.orig/drivers/hwmon/adcxx.c
> +++ linux-2.6.26-rc/drivers/hwmon/adcxx.c
> @@ -5,13 +5,15 @@
> *
> * Copyright (c) 2008 Marc Pignat <[email protected]>
> *
> + * 8 channel support added by Tobias Himmer <[email protected]>
> + *
> * The adcxx4s communicates with a host processor via an SPI/Microwire Bus
> * interface. This driver supports the whole family of devices with name
> * ADC<bb><c>S<sss>, where
> * * bb is the resolution in number of bits (8, 10, 12)
> - * * c is the number of channels (1, 2, 4)
> - * * sss is the maximum conversion speed (021 for 200 kSPS, 051 for 500 kSPS
> - * and 101 for 1 MSPS)
> + * * c is the number of channels (1, 2, 4, 8)
> + * * sss is the maximum conversion speed (021 for 200 kSPS, 051 / 052 for
> + * 500 kSPS and 101 for 1 MSPS)
> *
> * Complete datasheets are available at National's website here:
> * http://www.national.com/ds/DC/ADC<bb><c>S<sss>.pdf
> @@ -155,6 +157,10 @@ static struct sensor_device_attribute ad
> SENSOR_ATTR(in1_input, S_IRUGO, adcxx_read, NULL, 1),
> SENSOR_ATTR(in2_input, S_IRUGO, adcxx_read, NULL, 2),
> SENSOR_ATTR(in3_input, S_IRUGO, adcxx_read, NULL, 3),
> + SENSOR_ATTR(in4_input, S_IRUGO, adcxx_read, NULL, 4),
> + SENSOR_ATTR(in5_input, S_IRUGO, adcxx_read, NULL, 5),
> + SENSOR_ATTR(in6_input, S_IRUGO, adcxx_read, NULL, 6),
> + SENSOR_ATTR(in7_input, S_IRUGO, adcxx_read, NULL, 7),
> };
>
> /*----------------------------------------------------------------------*/
> @@ -218,6 +224,11 @@ static int __devinit adcxx4s_probe(struc
> return adcxx_probe(spi, 4);
> }
>
> +static int __devinit adcxx8s_probe(struct spi_device *spi)
> +{
> + return adcxx_probe(spi, 8);
> +}
> +
> static int __devexit adcxx_remove(struct spi_device *spi)
> {
> struct adcxx *adc = dev_get_drvdata(&spi->dev);
> @@ -259,6 +270,15 @@ static struct spi_driver adcxx4s_driver
> .remove = __devexit_p(adcxx_remove),
> };
>
> +static struct spi_driver adcxx8s_driver = {
> + .driver = {
> + .name = "adcxx8s",
> + .owner = THIS_MODULE,
> + },
> + .probe = adcxx8s_probe,
> + .remove = __devexit_p(adcxx_remove),
> +};
> +
> static int __init init_adcxx(void)
> {
> int status;
> @@ -270,7 +290,11 @@ static int __init init_adcxx(void)
> if (status)
> return status;
>
> - return spi_register_driver(&adcxx4s_driver);
> + status = spi_register_driver(&adcxx4s_driver);
> + if (status)
> + return status;
> +
> + return spi_register_driver(&adcxx8s_driver);
> }
>
> static void __exit exit_adcxx(void)
> @@ -278,6 +302,7 @@ static void __exit exit_adcxx(void)
> spi_unregister_driver(&adcxx1s_driver);
> spi_unregister_driver(&adcxx2s_driver);
> spi_unregister_driver(&adcxx4s_driver);
> + spi_unregister_driver(&adcxx8s_driver);
> }
>
> module_init(init_adcxx);
> @@ -290,3 +315,4 @@ MODULE_LICENSE("GPL");
> MODULE_ALIAS("adcxx1s");
> MODULE_ALIAS("adcxx2s");
> MODULE_ALIAS("adcxx4s");
> +MODULE_ALIAS("adcxx8s");
> Index: linux-2.6.26-rc/drivers/hwmon/Kconfig
> ===================================================================
> --- linux-2.6.26-rc.orig/drivers/hwmon/Kconfig
> +++ linux-2.6.26-rc/drivers/hwmon/Kconfig
> @@ -397,9 +397,9 @@ config SENSORS_ADCXX
> If you say yes here you get support for the National Semiconductor
> ADC<bb><c>S<sss> chip family, where
> * bb is the resolution in number of bits (8, 10, 12)
> - * c is the number of channels (1, 2, 4)
> - * sss is the maximum conversion speed (021 for 200 kSPS, 051 for 500
> - kSPS and 101 for 1 MSPS)
> + * c is the number of channels (1, 2, 4, 8)
> + * sss is the maximum conversion speed (021 for 200 kSPS, 051 / 052 for
> + 500 kSPS and 101 for 1 MSPS)
>
> Examples : ADC081S101, ADC124S501, ...
>
> --
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On Wed, 23 Jul 2008 13:07:54 +0200 Marc Pignat <[email protected]> wrote:
> SPI driver for analog to digital converters national semiconductor ADC081S101,
> ADC124S501, ...
>
> Signed-off-by: Marc Pignat <[email protected]>
>
> Hi all!
>
> patch against 2.6.26, tested on a custom arm board and only compil-tested on
> x86.
>
> This driver add support for National Semiconductor ADC<bb><c>S<sss> chip family,
> where:
> * bb is the resolution in number of bits (8, 10, 12)
> * c is the number of channels (1, 2, 4)
> * sss is the maximum conversion speed (021 for 200 kSPS, 051 for 500
> kSPS and 101 for 1 MSPS)
>
> Some remarks:
> * The chip type (-> the number of inputs) are determined by the module alias,
> is it a good idea? it could be implemented using platform data.
>
> * The Makefile seems ordered alphabetically, what order should be used for
> the Konfig file?
>
That changelog is a bit of a mess. I cleaned up up as:
SPI driver for analog to digital converters national semiconductor
ADC081S101, ADC124S501, ...
This driver adds support for National Semiconductor ADC<bb><c>S<sss> chip
family, where:
* bb is the resolution in number of bits (8, 10, 12)
* c is the number of channels (1, 2, 4)
* sss is the maximum conversion speed (021 for 200 kSPS, 051 for 500
kSPS and 101 for 1 MSPS)
Some remarks:
* The chip type (-> the number of inputs) are determined by the module
alias, is it a good idea? it could be implemented using platform data.
Signed-off-by: Marc Pignat <[email protected]>
Cc: "Mark M. Hoffman" <[email protected]>
Cc: Jean Delvare <[email protected]>
Cc: David Brownell <[email protected]>
but then didn't apply the patch.
>
> ...
>
> +/* sysfs hook function */
> +static ssize_t adcxx_read(struct device *dev,
> + struct device_attribute *devattr, char *buf)
> +{
> + struct spi_device *spi = to_spi_device(dev);
> + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> + struct adcxx *adc = dev_get_drvdata(&spi->dev);
> +
> + u8 tx_buf[2] = { attr->index << 3 }; /* other bits are don't care */
> + u8 rx_buf[2];
> + int status;
> + int value;
The driver has rather a lot of inexplicable blank lines in the middle
of the automatic variable definitions. The preferred style is no blank
lines within the definitions and a single blank line after them all,
thanks.
>
> ...
>
> +static int __devinit adcxx_probe(struct spi_device *spi, int channels)
> +{
> + struct adcxx *adc;
> + int status;
> + int i;
> +
> + adc = kzalloc(sizeof *adc, GFP_KERNEL);
> + if (!adc)
> + return -ENOMEM;
> +
> + /* set a default value for the reference */
> + adc->reference = 3300;
> +
> + adc->channels = channels;
> +
> + mutex_init(&adc->lock);
> +
> + dev_set_drvdata(&spi->dev, adc);
> +
> + for (i = 0; i < 3 + adc->channels; i++) {
> + status = device_create_file(&spi->dev, &ad_input[i].dev_attr);
> + if (status)
> + goto out_dev_create_file_failed;
> + }
> +
> + adc->hwmon_dev = hwmon_device_register(&spi->dev);
> + if (IS_ERR(adc->hwmon_dev)) {
> + dev_dbg(&spi->dev, "hwmon_device_register failed.\n");
> + status = PTR_ERR(adc->hwmon_dev);
> + goto out_dev_reg_failed;
> + }
> +
> + return 0;
> +
> +out_dev_create_file_failed:
> + hwmon_device_unregister(adc->hwmon_dev);
> + for (i = 0; i < 3 + adc->channels; i++)
> + device_remove_file(&spi->dev, &ad_input[i].dev_attr);
> +out_dev_reg_failed:
> + dev_set_drvdata(&spi->dev, NULL);
> + kfree(adc);
> + return status;
> +}
The error recovery here is messed up. The targets of the `goto's are
reversed. But even if that is fixed, we can end up doing
device_remove_file() of objects which weren't successfully created.
That might work, or it might generate runtime warnings or it might
crash. I don't know. It'd be best to just avoid doing it?