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path: root/drivers/mfd/wm831x-i2c.c
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Diffstat (limited to 'drivers/mfd/wm831x-i2c.c')
-rw-r--r--drivers/mfd/wm831x-i2c.c143
1 files changed, 143 insertions, 0 deletions
diff --git a/drivers/mfd/wm831x-i2c.c b/drivers/mfd/wm831x-i2c.c
new file mode 100644
index 000000000000..156b19859e81
--- /dev/null
+++ b/drivers/mfd/wm831x-i2c.c
@@ -0,0 +1,143 @@
+/*
+ * wm831x-i2c.c -- I2C access for Wolfson WM831x PMICs
+ *
+ * Copyright 2009,2010 Wolfson Microelectronics PLC.
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ *
+ * 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.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include <linux/mfd/core.h>
+#include <linux/slab.h>
+
+#include <linux/mfd/wm831x/core.h>
+#include <linux/mfd/wm831x/pdata.h>
+
+static int wm831x_i2c_read_device(struct wm831x *wm831x, unsigned short reg,
+ int bytes, void *dest)
+{
+ struct i2c_client *i2c = wm831x->control_data;
+ int ret;
+ u16 r = cpu_to_be16(reg);
+
+ ret = i2c_master_send(i2c, (unsigned char *)&r, 2);
+ if (ret < 0)
+ return ret;
+ if (ret != 2)
+ return -EIO;
+
+ ret = i2c_master_recv(i2c, dest, bytes);
+ if (ret < 0)
+ return ret;
+ if (ret != bytes)
+ return -EIO;
+ return 0;
+}
+
+/* Currently we allocate the write buffer on the stack; this is OK for
+ * small writes - if we need to do large writes this will need to be
+ * revised.
+ */
+static int wm831x_i2c_write_device(struct wm831x *wm831x, unsigned short reg,
+ int bytes, void *src)
+{
+ struct i2c_client *i2c = wm831x->control_data;
+ unsigned char msg[bytes + 2];
+ int ret;
+
+ reg = cpu_to_be16(reg);
+ memcpy(&msg[0], &reg, 2);
+ memcpy(&msg[2], src, bytes);
+
+ ret = i2c_master_send(i2c, msg, bytes + 2);
+ if (ret < 0)
+ return ret;
+ if (ret < bytes + 2)
+ return -EIO;
+
+ return 0;
+}
+
+static int wm831x_i2c_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ struct wm831x *wm831x;
+
+ wm831x = kzalloc(sizeof(struct wm831x), GFP_KERNEL);
+ if (wm831x == NULL)
+ return -ENOMEM;
+
+ i2c_set_clientdata(i2c, wm831x);
+ wm831x->dev = &i2c->dev;
+ wm831x->control_data = i2c;
+ wm831x->read_dev = wm831x_i2c_read_device;
+ wm831x->write_dev = wm831x_i2c_write_device;
+
+ return wm831x_device_init(wm831x, id->driver_data, i2c->irq);
+}
+
+static int wm831x_i2c_remove(struct i2c_client *i2c)
+{
+ struct wm831x *wm831x = i2c_get_clientdata(i2c);
+
+ wm831x_device_exit(wm831x);
+
+ return 0;
+}
+
+static int wm831x_i2c_suspend(struct i2c_client *i2c, pm_message_t mesg)
+{
+ struct wm831x *wm831x = i2c_get_clientdata(i2c);
+
+ return wm831x_device_suspend(wm831x);
+}
+
+static const struct i2c_device_id wm831x_i2c_id[] = {
+ { "wm8310", WM8310 },
+ { "wm8311", WM8311 },
+ { "wm8312", WM8312 },
+ { "wm8320", WM8320 },
+ { "wm8321", WM8321 },
+ { "wm8325", WM8325 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, wm831x_i2c_id);
+
+
+static struct i2c_driver wm831x_i2c_driver = {
+ .driver = {
+ .name = "wm831x",
+ .owner = THIS_MODULE,
+ },
+ .probe = wm831x_i2c_probe,
+ .remove = wm831x_i2c_remove,
+ .suspend = wm831x_i2c_suspend,
+ .id_table = wm831x_i2c_id,
+};
+
+static int __init wm831x_i2c_init(void)
+{
+ int ret;
+
+ ret = i2c_add_driver(&wm831x_i2c_driver);
+ if (ret != 0)
+ pr_err("Failed to register wm831x I2C driver: %d\n", ret);
+
+ return ret;
+}
+subsys_initcall(wm831x_i2c_init);
+
+static void __exit wm831x_i2c_exit(void)
+{
+ i2c_del_driver(&wm831x_i2c_driver);
+}
+module_exit(wm831x_i2c_exit);