This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / drivers / macintosh / windfarm_max6690_sensor.c

diff --git a/drivers/macintosh/windfarm_max6690_sensor.c b/drivers/macintosh/windfarm_max6690_sensor.c
new file mode 100644 (file)
index 0000000..eae1189
--- /dev/null
+++ b/drivers/macintosh/windfarm_max6690_sensor.c
@@ -0,0 +1,179 @@
+/*
+ * Windfarm PowerMac thermal control.  MAX6690 sensor.
+ *
+ * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
+ *
+ * Use and redistribute under the terms of the GNU GPL v2.
+ */
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <asm/prom.h>
+#include <asm/pmac_low_i2c.h>
+
+#include "windfarm.h"
+
+#define VERSION "0.2"
+
+/* This currently only exports the external temperature sensor,
+   since that's all the control loops need. */
+
+/* Some MAX6690 register numbers */
+#define MAX6690_INTERNAL_TEMP  0
+#define MAX6690_EXTERNAL_TEMP  1
+
+struct wf_6690_sensor {
+       struct i2c_client       i2c;
+       struct wf_sensor        sens;
+};
+
+#define wf_to_6690(x)  container_of((x), struct wf_6690_sensor, sens)
+#define i2c_to_6690(x) container_of((x), struct wf_6690_sensor, i2c)
+
+static int wf_max6690_attach(struct i2c_adapter *adapter);
+static int wf_max6690_detach(struct i2c_client *client);
+
+static struct i2c_driver wf_max6690_driver = {
+       .driver = {
+               .name           = "wf_max6690",
+       },
+       .attach_adapter = wf_max6690_attach,
+       .detach_client  = wf_max6690_detach,
+};
+
+static int wf_max6690_get(struct wf_sensor *sr, s32 *value)
+{
+       struct wf_6690_sensor *max = wf_to_6690(sr);
+       s32 data;
+
+       if (max->i2c.adapter == NULL)
+               return -ENODEV;
+
+       /* chip gets initialized by firmware */
+       data = i2c_smbus_read_byte_data(&max->i2c, MAX6690_EXTERNAL_TEMP);
+       if (data < 0)
+               return data;
+       *value = data << 16;
+       return 0;
+}
+
+static void wf_max6690_release(struct wf_sensor *sr)
+{
+       struct wf_6690_sensor *max = wf_to_6690(sr);
+
+       if (max->i2c.adapter) {
+               i2c_detach_client(&max->i2c);
+               max->i2c.adapter = NULL;
+       }
+       kfree(max);
+}
+
+static struct wf_sensor_ops wf_max6690_ops = {
+       .get_value      = wf_max6690_get,
+       .release        = wf_max6690_release,
+       .owner          = THIS_MODULE,
+};
+
+static void wf_max6690_create(struct i2c_adapter *adapter, u8 addr)
+{
+       struct wf_6690_sensor *max;
+       char *name = "backside-temp";
+
+       max = kzalloc(sizeof(struct wf_6690_sensor), GFP_KERNEL);
+       if (max == NULL) {
+               printk(KERN_ERR "windfarm: Couldn't create MAX6690 sensor %s: "
+                      "no memory\n", name);
+               return;
+       }
+
+       max->sens.ops = &wf_max6690_ops;
+       max->sens.name = name;
+       max->i2c.addr = addr >> 1;
+       max->i2c.adapter = adapter;
+       max->i2c.driver = &wf_max6690_driver;
+       strncpy(max->i2c.name, name, I2C_NAME_SIZE-1);
+
+       if (i2c_attach_client(&max->i2c)) {
+               printk(KERN_ERR "windfarm: failed to attach MAX6690 sensor\n");
+               goto fail;
+       }
+
+       if (wf_register_sensor(&max->sens)) {
+               i2c_detach_client(&max->i2c);
+               goto fail;
+       }
+
+       return;
+
+ fail:
+       kfree(max);
+}
+
+static int wf_max6690_attach(struct i2c_adapter *adapter)
+{
+       struct device_node *busnode, *dev = NULL;
+       struct pmac_i2c_bus *bus;
+       const char *loc;
+
+       bus = pmac_i2c_adapter_to_bus(adapter);
+       if (bus == NULL)
+               return -ENODEV;
+       busnode = pmac_i2c_get_bus_node(bus);
+
+       while ((dev = of_get_next_child(busnode, dev)) != NULL) {
+               u8 addr;
+
+               /* We must re-match the adapter in order to properly check
+                * the channel on multibus setups
+                */
+               if (!pmac_i2c_match_adapter(dev, adapter))
+                       continue;
+               if (!device_is_compatible(dev, "max6690"))
+                       continue;
+               addr = pmac_i2c_get_dev_addr(dev);
+               loc = get_property(dev, "hwsensor-location", NULL);
+               if (loc == NULL || addr == 0)
+                       continue;
+               printk("found max6690, loc=%s addr=0x%02x\n", loc, addr);
+               if (strcmp(loc, "BACKSIDE"))
+                       continue;
+               wf_max6690_create(adapter, addr);
+       }
+
+       return 0;
+}
+
+static int wf_max6690_detach(struct i2c_client *client)
+{
+       struct wf_6690_sensor *max = i2c_to_6690(client);
+
+       max->i2c.adapter = NULL;
+       wf_unregister_sensor(&max->sens);
+
+       return 0;
+}
+
+static int __init wf_max6690_sensor_init(void)
+{
+       /* Don't register on old machines that use therm_pm72 for now */
+       if (machine_is_compatible("PowerMac7,2") ||
+           machine_is_compatible("PowerMac7,3") ||
+           machine_is_compatible("RackMac3,1"))
+               return -ENODEV;
+       return i2c_add_driver(&wf_max6690_driver);
+}
+
+static void __exit wf_max6690_sensor_exit(void)
+{
+       i2c_del_driver(&wf_max6690_driver);
+}
+
+module_init(wf_max6690_sensor_init);
+module_exit(wf_max6690_sensor_exit);
+
+MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
+MODULE_DESCRIPTION("MAX6690 sensor objects for PowerMac thermal control");
+MODULE_LICENSE("GPL");