[PATCH] hwmon: Driver for as1531, Austria-Microsystem Analog to Digital Converter.

From: fabien . marteau
Date: Mon May 16 2011 - 10:41:34 EST

From: Fabien Marteau <fabien.marteau@xxxxxxxxxxxx>


Signed-off-by: Fabien Marteau <fabien.marteau@xxxxxxxxxxxx>
---
drivers/hwmon/Kconfig | 10 ++
drivers/hwmon/Makefile | 1 +
drivers/hwmon/as1531.c | 297 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 308 insertions(+), 0 deletions(-)
create mode 100644 drivers/hwmon/as1531.c

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 50e40db..d2ba655 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -104,6 +104,16 @@ config SENSORS_ADCXX
This driver can also be built as a module. If so, the module
will be called adcxx.

+config SENSORS_AS1531
+ tristate "Austria Microsystems AS1531 Analog to Digital Converter"
+ depends on SPI_MASTER
+ help
+ If you say yes here you get support for Austria Microsystems AS1531.
+ AS1531 is a 12 bits Analog to digitals converter with 8 channels
+ provided by Austria-Microsystems company.
+ This driver can also be built as a module. If so, the module
+ will be called as1531.
+
config SENSORS_ADM1021
tristate "Analog Devices ADM1021 and compatibles"
depends on I2C
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 967d0ea..8a304b3 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_SENSORS_ABITUGURU3)+= abituguru3.o
obj-$(CONFIG_SENSORS_AD7414) += ad7414.o
obj-$(CONFIG_SENSORS_AD7418) += ad7418.o
obj-$(CONFIG_SENSORS_ADCXX) += adcxx.o
+obj-$(CONFIG_SENSORS_AS1531) += as1531.o
obj-$(CONFIG_SENSORS_ADM1021) += adm1021.o
obj-$(CONFIG_SENSORS_ADM1025) += adm1025.o
obj-$(CONFIG_SENSORS_ADM1026) += adm1026.o
diff --git a/drivers/hwmon/as1531.c b/drivers/hwmon/as1531.c
new file mode 100644
index 0000000..3384663
--- /dev/null
+++ b/drivers/hwmon/as1531.c
@@ -0,0 +1,297 @@
+/*
+ * as1531.c
+ *
+ * Driver for Austria-Microsystem Analog to Digital Converter.
+ *
+ * Copyright (c) 2010, 2011 Fabien Marteau <fabien.marteau@xxxxxxxxxxxx>
+ * Driver based on Marc Pignat <marc.pignat@xxxxxxx> adcxx.c driver.
+ *
+ * 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 AS1531_SPI_SPEED 64941
+#define AS1531_MAX_VALUE 2500
+
+#define AS1531_START_BIT (0x80)
+#define AS1531_CHAN0 (0<<4)
+#define AS1531_CHAN1 (4<<4)
+#define AS1531_CHAN2 (1<<4)
+#define AS1531_CHAN3 (5<<4)
+#define AS1531_CHAN4 (2<<4)
+#define AS1531_CHAN5 (6<<4)
+#define AS1531_CHAN6 (3<<4)
+#define AS1531_CHAN7 (7<<4)
+
+#define AS1531_RANGE_0_TO_VREF (1<<3)
+#define AS1531_RANGE_HALFVREF_TO_HALFVREF (0<<3)
+
+#define AS1531_MODE_COM (1<<2)
+#define AS1531_MODE_DIFF (0<<2)
+
+#define AS1531_POWER_DOWN 0x0
+#define AS1531_POWER_REDUCED 0x1
+#define AS1531_POWER_REDUCED_BIS 0x2
+#define AS1531_POWER_NORMAL 0x3
+
+struct as1531 {
+ struct device *hwmon_dev;
+ struct mutex lock;
+};
+
+static int as1531_message(struct spi_device *spi, int cmd, int *ret_value)
+{
+ struct spi_message message;
+ struct spi_transfer x[1];
+ int status, i;
+ u8 cmd_send;
+ unsigned char buf[64];
+ unsigned char buf_read[64];
+
+ cmd_send = cmd;
+
+ spi_message_init(&message);
+ memset(x, 0, sizeof x);
+ memset(buf, 0, sizeof(buf));
+ memset(buf_read, 0, sizeof(buf_read));
+
+ for (i = 0; i < 8; i++) {
+ buf[i] = ((cmd_send & 0x80)>>7);
+ cmd_send = cmd_send << 1;
+ }
+
+ x[0].tx_buf = buf;
+ x[0].len = 24;
+ x[0].rx_buf = buf_read;
+ x[0].speed_hz = AS1531_SPI_SPEED;
+ x[0].bits_per_word = 1;
+ spi_message_add_tail(&x[0], &message);
+
+ status = spi_sync(spi, &message);
+ if (status < 0)
+ return status;
+
+ *ret_value = buf_read[11] & 0x01;
+ for (i = 12; i < 23 ; i++) {
+ *ret_value = *ret_value << 1;
+ *ret_value = *ret_value | (buf_read[i]&0x01);
+ }
+
+ return 0;
+}
+
+static ssize_t as1531_read(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct as1531 *adc = dev_get_drvdata(&spi->dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ int status = 0;
+ int ret_value;
+ int32_t cmd;
+
+
+ if (mutex_lock_interruptible(&adc->lock))
+ return -ERESTARTSYS;
+
+ switch (attr->index) {
+ case 0:
+ cmd = AS1531_START_BIT | AS1531_CHAN0 |
+ AS1531_RANGE_0_TO_VREF | AS1531_MODE_COM |
+ AS1531_POWER_NORMAL;
+ break;
+ case 1:
+ cmd = AS1531_START_BIT | AS1531_CHAN1 |
+ AS1531_RANGE_0_TO_VREF | AS1531_MODE_COM |
+ AS1531_POWER_NORMAL;
+ break;
+ case 2:
+ cmd = AS1531_START_BIT | AS1531_CHAN2 |
+ AS1531_RANGE_0_TO_VREF | AS1531_MODE_COM |
+ AS1531_POWER_NORMAL;
+ break;
+ case 3:
+ cmd = AS1531_START_BIT | AS1531_CHAN3 |
+ AS1531_RANGE_0_TO_VREF | AS1531_MODE_COM |
+ AS1531_POWER_NORMAL;
+ break;
+ case 4:
+ cmd = AS1531_START_BIT | AS1531_CHAN4 |
+ AS1531_RANGE_0_TO_VREF | AS1531_MODE_COM |
+ AS1531_POWER_NORMAL;
+ break;
+ case 5:
+ cmd = AS1531_START_BIT | AS1531_CHAN5 |
+ AS1531_RANGE_0_TO_VREF | AS1531_MODE_COM |
+ AS1531_POWER_NORMAL;
+ break;
+ case 6:
+ cmd = AS1531_START_BIT | AS1531_CHAN6 |
+ AS1531_RANGE_0_TO_VREF | AS1531_MODE_COM |
+ AS1531_POWER_NORMAL;
+ break;
+ case 7:
+ cmd = AS1531_START_BIT | AS1531_CHAN7 |
+ AS1531_RANGE_0_TO_VREF | AS1531_MODE_COM |
+ AS1531_POWER_NORMAL;
+ break;
+ default:
+ status = -EINVAL;
+ goto out;
+ }
+ status = as1531_message(spi, cmd, &ret_value);
+ if (status < 0)
+ goto out;
+
+ status = sprintf(buf, "%d\n", ret_value*2500/4096);
+out:
+ mutex_unlock(&adc->lock);
+ return status;
+}
+
+
+static ssize_t as1531_show_min(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ return sprintf(buf, "0\n");
+}
+
+static ssize_t as1531_show_max(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ return sprintf(buf, "%d\n", AS1531_MAX_VALUE);
+}
+
+static ssize_t as1531_show_name(struct device *dev, struct device_attribute
+ *devattr, char *buf)
+{
+ return sprintf(buf, "as1531\n");
+}
+
+static struct sensor_device_attribute as1531_input[] = {
+ SENSOR_ATTR(name, S_IRUGO, as1531_show_name, NULL, 0),
+ SENSOR_ATTR(in_min, S_IRUGO, as1531_show_min, NULL, 0),
+ SENSOR_ATTR(in_max, S_IRUGO, as1531_show_max, NULL, 0),
+ SENSOR_ATTR(in0_input, S_IRUGO, as1531_read, NULL, 0),
+ SENSOR_ATTR(in1_input, S_IRUGO, as1531_read, NULL, 1),
+ SENSOR_ATTR(in2_input, S_IRUGO, as1531_read, NULL, 2),
+ SENSOR_ATTR(in3_input, S_IRUGO, as1531_read, NULL, 3),
+ SENSOR_ATTR(in4_input, S_IRUGO, as1531_read, NULL, 4),
+ SENSOR_ATTR(in5_input, S_IRUGO, as1531_read, NULL, 5),
+ SENSOR_ATTR(in6_input, S_IRUGO, as1531_read, NULL, 6),
+ SENSOR_ATTR(in7_input, S_IRUGO, as1531_read, NULL, 7),
+};
+
+/*----------------------------------------------------------------------*/
+
+static int __devinit as1531_probe(struct spi_device *spi)
+{
+ struct as1531 *adc;
+ int status;
+ int i;
+
+ adc = kzalloc(sizeof(struct as1531), GFP_KERNEL);
+ if (adc == NULL)
+ return -ENOMEM;
+
+ mutex_init(&adc->lock);
+ mutex_lock(&adc->lock);
+
+ dev_set_drvdata(&spi->dev, adc);
+
+ for (i = 0; i < 11; i++) {
+ status = device_create_file(&spi->dev,
+ &as1531_input[i].dev_attr);
+ if (status < 0) {
+ dev_err(&spi->dev, "device_create_file failed.\n");
+ goto out_err;
+ }
+ }
+
+ adc->hwmon_dev = hwmon_device_register(&spi->dev);
+ if (IS_ERR(adc->hwmon_dev)) {
+ dev_err(&spi->dev, "hwmon_device_register failed.\n");
+ status = PTR_ERR(adc->hwmon_dev);
+ goto out_err;
+ }
+
+ mutex_unlock(&adc->lock);
+ return 0;
+
+out_err:
+ for (i--; i >= 0; i--)
+ device_remove_file(&spi->dev, &as1531_input[i].dev_attr);
+ dev_set_drvdata(&spi->dev, NULL);
+ mutex_unlock(&adc->lock);
+ kfree(adc);
+ return status;
+}
+
+static int __devexit as1531_remove(struct spi_device *spi)
+{
+ struct as1531 *adc = dev_get_drvdata(&spi->dev);
+ int i;
+
+ mutex_lock(&adc->lock);
+ hwmon_device_unregister(adc->hwmon_dev);
+ for (i = 0; i < 8; i++)
+ device_remove_file(&spi->dev, &as1531_input[i].dev_attr);
+
+ dev_set_drvdata(&spi->dev, NULL);
+ mutex_unlock(&adc->lock);
+ kfree(adc);
+
+ return 0;
+}
+
+/* SPI structures */
+
+static struct spi_driver as1531_driver = {
+ .driver = {
+ .name = "as1531",
+ .owner = THIS_MODULE,
+ },
+ .probe = as1531_probe,
+ .remove = __devexit_p(as1531_remove),
+};
+
+/* Init module */
+
+static int __init init_as1531(void)
+{
+ return spi_register_driver(&as1531_driver);
+}
+
+static void __exit exit_as1531(void)
+{
+ spi_unregister_driver(&as1531_driver);
+}
+
+module_init(init_as1531);
+module_exit(exit_as1531);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Fabien Marteau <fabien.marteau@xxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Driver for AS1531 ADC");
--
1.7.0.4

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