From: Rodolfo Giometti <[email protected]>

Signed-off-by: Rodolfo Giometti <[email protected]>
---
 drivers/i2c/chips/Kconfig    |   10 +
 drivers/i2c/chips/Makefile   |    1 +
 drivers/i2c/chips/mma7455l.c |  372 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 383 insertions(+), 0 deletions(-)
 create mode 100644 drivers/i2c/chips/mma7455l.c

diff --git a/drivers/i2c/chips/Kconfig b/drivers/i2c/chips/Kconfig
index 7c5a497..815fca4 100644
--- a/drivers/i2c/chips/Kconfig
+++ b/drivers/i2c/chips/Kconfig
@@ -112,4 +112,14 @@ config SENSORS_HMC6343
          This driver can also be built as a module.  If so, the module
          will be called hmc6343.
 
+config SENSORS_MMA7455L
+       tristate "Freescale 2g/4g/8g 3-Axis low-g accelerometer"
+       depends on EXPERIMENTAL
+       help
+         If you say yes here you get support for the Freescale 2g/4g/8g
+         3-Axis low-g accelerometer.
+
+         This driver can also be built as a module.  If so, the module
+         will be called mma7455l.
+
 endmenu
diff --git a/drivers/i2c/chips/Makefile b/drivers/i2c/chips/Makefile
index a6c7305..631207e 100644
--- a/drivers/i2c/chips/Makefile
+++ b/drivers/i2c/chips/Makefile
@@ -18,6 +18,7 @@ obj-$(CONFIG_PCF8575)         += pcf8575.o
 obj-$(CONFIG_SENSORS_PCF8591)  += pcf8591.o
 obj-$(CONFIG_SENSORS_TSL2550)  += tsl2550.o
 obj-$(CONFIG_SENSORS_HMC6343)  += hmc6343.o
+obj-$(CONFIG_SENSORS_MMA7455L) += mma7455l.o
 
 ifeq ($(CONFIG_I2C_DEBUG_CHIP),y)
 EXTRA_CFLAGS += -DDEBUG
diff --git a/drivers/i2c/chips/mma7455l.c b/drivers/i2c/chips/mma7455l.c
new file mode 100644
index 0000000..01a9c19
--- /dev/null
+++ b/drivers/i2c/chips/mma7455l.c
@@ -0,0 +1,372 @@
+/*
+ *  mma7455l.c - driver for 3-Axis digital low-g accelerometer
+ *
+ *  Copyright (C) 2008-2009 Rodolfo Giometti <[email protected]>
+ *  Copyright (C) 2008-2009 Eurotech S.p.A. <[email protected]>
+ *
+ *  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/slab.h>
+#include <linux/i2c.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+
+#include <linux/i2c/mma7455l.h>
+
+#define DRIVER_VERSION         "0.40.0"
+
+/*
+ * Defines
+ */
+
+#define ACCEL_DATA             0x00
+#define MCTL                   0x16
+#define    GSEL_SHIFT             2
+#define    GSEL_MASK              (3 << 2)
+#define    GSEL_NOP               3
+#define    MOD_SHIFT              0
+#define    MOD_MASK               (3 << 0)
+
+static char *mode_lut[] = {
+       "standby", "measurement", "level", "pulse",
+};
+
+/*
+ * Structs
+ */
+
+struct maa7455l_data {
+       struct mutex update_lock;
+};
+
+/*
+ * Management functions
+ */
+
+static int get_angle(struct i2c_client *client, u8 type, s16 *a)
+{
+       struct maa7455l_data *data = i2c_get_clientdata(client);
+       struct i2c_msg msg1[] = {
+               { client->addr, 0, 1, &type },
+       };
+       u8 d[6];
+       struct i2c_msg msg2[] = {
+               { client->addr, I2C_M_RD, 6, d },
+       };
+       int ret;
+
+       mutex_lock(&data->update_lock);
+
+       /* FIXME: should check DRDY flag */
+
+       ret = i2c_transfer(client->adapter, msg1, 1);
+       if (ret < 0)
+               goto exit;
+
+       mdelay(1);
+
+       ret = i2c_transfer(client->adapter, msg2, 1);
+       if (ret < 0)
+               goto exit;
+       ret = 0;
+exit:
+       mutex_unlock(&data->update_lock);
+
+       a[0] = (s16) ((d[1] << 8) | d[0]);
+       a[1] = (s16) ((d[3] << 8) | d[2]);
+       a[2] = (s16) ((d[5] << 8) | d[4]);
+
+       return ret;
+}
+
+static int write_g_select(struct i2c_client *client, int val)
+{
+       struct maa7455l_data *data = i2c_get_clientdata(client);
+       int ret;
+
+       switch (val) {
+       case 2:
+               val = GSEL_2;
+               break;
+       case 4:
+               val = GSEL_4;
+               break;
+       case 8:
+               val = GSEL_8;
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       mutex_lock(&data->update_lock);
+
+       ret = i2c_smbus_read_byte_data(client, MCTL);
+       if (ret < 0)
+               goto exit;
+
+       ret &= ~GSEL_MASK;
+       ret |= val << GSEL_SHIFT;
+
+       ret = i2c_smbus_write_byte_data(client, MCTL, ret);
+       if (ret < 0)
+               goto exit;
+       ret = 0;
+exit:
+       mutex_unlock(&data->update_lock);
+
+       return ret;
+}
+
+static int write_mode(struct i2c_client *client, int val)
+{
+       struct maa7455l_data *data = i2c_get_clientdata(client);
+       int ret;
+
+       if (val < 0 || val > 3)
+               return -EINVAL;
+
+       mutex_lock(&data->update_lock);
+       ret = i2c_smbus_read_byte_data(client, MCTL);
+       if (ret < 0)
+               goto exit;
+
+       ret &= ~MOD_MASK;
+       ret |= val << MOD_SHIFT;
+
+       ret = i2c_smbus_write_byte_data(client, MCTL, ret);
+       if (ret < 0)
+               goto exit;
+       ret = 0;
+exit:
+       mutex_unlock(&data->update_lock);
+
+       return ret;
+}
+
+/*
+ * SysFS support
+ */
+
+static ssize_t show_accel(struct device *dev,
+                               struct device_attribute *attr, char *buf)
+{
+       s16 data[3];
+       int ret = get_angle(to_i2c_client(dev), ACCEL_DATA, data);
+       if (ret < 0)
+               return ret;
+
+       return sprintf(buf, "Ax:%d,Ay:%d,Az:%d\n", data[0], data[1], data[2]);
+}
+
+static DEVICE_ATTR(accel, S_IRUGO, show_accel, NULL);
+
+static ssize_t show_mode(struct device *dev,
+                               struct device_attribute *attr, char *buf)
+{
+       int ret = i2c_smbus_read_byte_data(to_i2c_client(dev), MCTL);
+       if (ret < 0)
+               return ret;
+
+       ret = (ret & MOD_MASK) >> MOD_SHIFT;
+       return sprintf(buf, "%s", mode_lut[ret]);
+}
+
+static ssize_t store_mode(struct device *dev,
+                               struct device_attribute *attr,
+                               const char *buf, size_t count)
+{
+       char *p;
+       int len, i, ret;
+
+       /* Remove '\n' from buf */
+       p = memchr(buf, '\n', count);
+       len = p ? p - buf : count;
+
+       for (i = 0; i < 4; i++)
+               if (!strncmp(buf, mode_lut[i], len))
+                       break;
+       if (i >= 4)
+               return -EINVAL;
+
+       ret = write_mode(to_i2c_client(dev), i);
+       return ret ? ret : count;
+}
+
+static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO, show_mode, store_mode);
+
+static ssize_t show_g_select(struct device *dev,
+                               struct device_attribute *attr, char *buf)
+{
+       int ret = i2c_smbus_read_byte_data(to_i2c_client(dev), MCTL);
+       if (ret < 0)
+               return ret;
+
+       ret = (ret & GSEL_MASK) >> GSEL_SHIFT;
+       if (ret == GSEL_NOP)
+               return -EINVAL;
+
+       return sprintf(buf, "%d", ret == GSEL_8 ? 8 : (ret == GSEL_2 ? 2 : 4));
+}
+
+static ssize_t store_g_select(struct device *dev,
+                               struct device_attribute *attr,
+                               const char *buf, size_t count)
+{
+       long val;
+       int ret = strict_strtol(buf, 10, &val);
+       if (ret)
+               return -EINVAL;
+
+       ret = write_g_select(to_i2c_client(dev), val);
+       return ret ? ret : count;
+}
+
+static DEVICE_ATTR(g_select, S_IWUSR | S_IRUGO, show_g_select, store_g_select);
+
+static struct attribute *mma7455l_attributes[] = {
+       &dev_attr_accel.attr,
+       &dev_attr_g_select.attr,
+       &dev_attr_mode.attr,
+       NULL
+};
+
+static const struct attribute_group mma7455l_attr_group = {
+       .attrs = mma7455l_attributes,
+};
+
+/*
+ * Initialization function
+ */
+
+static int mma7455l_init_client(struct i2c_client *client,
+                               struct mma7455l_platform_data *pdata)
+{
+       int ret;
+
+       /* Set the platform defaults */
+       ret = write_g_select(client, pdata->g_select);
+       if (ret)
+               dev_warn(&client->dev, "unable to init g selct to %d\n",
+                               pdata->g_select);
+       ret = write_mode(client, pdata->mode);
+       if (ret)
+               dev_warn(&client->dev, "unable to init mode to %d\n",
+                               pdata->mode);
+
+       return 0;
+}
+
+/*
+ * I2C init/probing/exit functions
+ */
+
+static struct mma7455l_platform_data defs;     /* all values are set to '0' */
+
+static struct i2c_driver mma7455l_driver;
+static int __devinit mma7455l_probe(struct i2c_client *client,
+                                       const struct i2c_device_id *id)
+{
+       struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+       struct maa7455l_data *data;
+       struct mma7455l_platform_data *pdata;
+       int ret = 0;
+
+       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE
+                                    | I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) {
+               ret = -EIO;
+               goto exit;
+       }
+
+       data = kzalloc(sizeof(struct maa7455l_data), GFP_KERNEL);
+       if (!data) {
+               ret = -ENOMEM;
+               goto exit;
+       }
+       i2c_set_clientdata(client, data);
+
+       /* Check platform data */
+       pdata = client->dev.platform_data;
+       if (!pdata)
+               pdata = &defs;
+       dev_info(&client->dev, "g select %d\n", pdata->g_select);
+       dev_info(&client->dev, "mode %d\n", pdata->mode);
+
+       mutex_init(&data->update_lock);
+
+       /* Initialize the MMA7455L chip */
+       ret = mma7455l_init_client(client, pdata);
+       if (ret)
+               goto exit_kfree;
+
+       /* Register sysfs hooks */
+       ret = sysfs_create_group(&client->dev.kobj, &mma7455l_attr_group);
+       if (ret)
+               goto exit_kfree;
+               goto exit;
+
+       dev_info(&client->dev, "support ver. %s enabled\n", DRIVER_VERSION);
+
+       return 0;
+
+exit_kfree:
+       kfree(data);
+exit:
+       return ret;
+}
+
+static int __devexit mma7455l_remove(struct i2c_client *client)
+{
+       sysfs_remove_group(&client->dev.kobj, &mma7455l_attr_group);
+
+       kfree(i2c_get_clientdata(client));
+
+       return 0;
+}
+
+static const struct i2c_device_id mma7455l_id[] = {
+       { "mma7455l", 0 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, mma7455l_id);
+
+static struct i2c_driver mma7455l_driver = {
+       .driver = {
+               .name   = "mma7455l",
+               .owner  = THIS_MODULE,
+       },
+       .probe  = mma7455l_probe,
+       .remove = __devexit_p(mma7455l_remove),
+       .id_table = mma7455l_id,
+};
+
+static int __init mma7455l_init(void)
+{
+       return i2c_add_driver(&mma7455l_driver);
+}
+
+static void __exit mma7455l_exit(void)
+{
+       i2c_del_driver(&mma7455l_driver);
+}
+
+MODULE_AUTHOR("Rodolfo Giometti <[email protected]>");
+MODULE_DESCRIPTION("MMA7455L 3-Axis digital low-g accelerometer");
+MODULE_LICENSE("GPL");
+
+module_init(mma7455l_init);
+module_exit(mma7455l_exit);
-- 
1.5.6.3

--
To unsubscribe from this list: send the line "unsubscribe linux-i2c" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to