drivers/misc: add driver for Texas Instruments DAC7512

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: "H Hartley Sweeten" <hartleys@visionengravers.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 112 insertions, 0 deletions

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 0c7f4c5dd07f..724d1188a322 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -270,6 +270,16 @@ config DS1682
           This driver can also be built as a module.  If so, the module
           will be called ds1682.
 
+config TI_DAC7512
+        tristate "Texas Instruments DAC7512"
+        depends on SPI && SYSFS
+        help
+          If you say yes here you get support for the Texas Instruments
+          DAC7512 16-bit digital-to-analog converter.
+
+          This driver can also be built as a module. If so, the module
+          will be calles ti_dac7512.
+
 source "drivers/misc/c2port/Kconfig"
 source "drivers/misc/eeprom/Kconfig"
 source "drivers/misc/cb710/Kconfig"
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 18c8418a5132..e76b77977442 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -22,6 +22,7 @@ obj-$(CONFIG_HP_ILO)		+= hpilo.o
 obj-$(CONFIG_ISL29003)          += isl29003.o
 obj-$(CONFIG_EP93XX_PWM)        += ep93xx_pwm.o
 obj-$(CONFIG_DS1682)            += ds1682.o
+obj-$(CONFIG_TI_DAC7512)        += ti_dac7512.o
 obj-$(CONFIG_C2PORT)            += c2port/
 obj-$(CONFIG_IWMC3200TOP)      += iwmc3200top/
 obj-y                           += eeprom/
diff --git a/drivers/misc/ti_dac7512.c b/drivers/misc/ti_dac7512.c
new file mode 100644
index 000000000000..d3f229a3a77e
--- /dev/null
+++ b/drivers/misc/ti_dac7512.c
@@ -0,0 +1,101 @@
+/*
+ *  dac7512.c - Linux kernel module for
+ *      Texas Instruments DAC7512
+ *
+ *  Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
+ *
+ *  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/module.h>
+#include <linux/init.h>
+#include <linux/spi/spi.h>
+
+#define DAC7512_DRV_NAME        "dac7512"
+#define DRIVER_VERSION          "1.0"
+
+static ssize_t dac7512_store_val(struct device *dev,
+                                 struct device_attribute *attr,
+                                 const char *buf, size_t count)
+{
+        struct spi_device *spi = to_spi_device(dev);
+        unsigned char tmp[2];
+        unsigned long val;
+
+        if (strict_strtoul(buf, 10, &val) < 0)
+                return -EINVAL;
+
+        tmp[0] = val >> 8;
+        tmp[1] = val & 0xff;
+        spi_write(spi, tmp, sizeof(tmp));
+        return count;
+}
+
+static DEVICE_ATTR(value, S_IWUSR, NULL, dac7512_store_val);
+
+static struct attribute *dac7512_attributes[] = {
+        &dev_attr_value.attr,
+        NULL
+};
+
+static const struct attribute_group dac7512_attr_group = {
+        .attrs = dac7512_attributes,
+};
+
+static int __devinit dac7512_probe(struct spi_device *spi)
+{
+        int ret;
+
+        spi->bits_per_word = 8;
+        spi->mode = SPI_MODE_0;
+        ret = spi_setup(spi);
+        if (ret < 0)
+                return ret;
+
+        return sysfs_create_group(&spi->dev.kobj, &dac7512_attr_group);
+}
+
+static int __devexit dac7512_remove(struct spi_device *spi)
+{
+        sysfs_remove_group(&spi->dev.kobj, &dac7512_attr_group);
+        return 0;
+}
+
+static struct spi_driver dac7512_driver = {
+        .driver = {
+                .name   = DAC7512_DRV_NAME,
+                .owner  = THIS_MODULE,
+        },
+        .probe  = dac7512_probe,
+        .remove = __devexit_p(dac7512_remove),
+};
+
+static int __init dac7512_init(void)
+{
+        return spi_register_driver(&dac7512_driver);
+}
+
+static void __exit dac7512_exit(void)
+{
+        spi_unregister_driver(&dac7512_driver);
+}
+
+MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
+MODULE_DESCRIPTION("DAC7512 16-bit DAC");
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION(DRIVER_VERSION);
+
+module_init(dac7512_init);
+module_exit(dac7512_exit);