--- /dev/null
+/*
+ * Windfarm PowerMac thermal control. LM75 sensor
+ *
+ * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
+ * <benh@kernel.crashing.org>
+ *
+ * Released under the term of the GNU GPL v2.
+ */
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/wait.h>
+#include <linux/i2c.h>
+#include <asm/prom.h>
+#include <asm/machdep.h>
+#include <asm/io.h>
+#include <asm/system.h>
+#include <asm/sections.h>
+#include <asm/pmac_low_i2c.h>
+
+#include "windfarm.h"
+
+#define VERSION "0.2"
+
+#undef DEBUG
+
+#ifdef DEBUG
+#define DBG(args...) printk(args)
+#else
+#define DBG(args...) do { } while(0)
+#endif
+
+struct wf_lm75_sensor {
+ int ds1775 : 1;
+ int inited : 1;
+ struct i2c_client i2c;
+ struct wf_sensor sens;
+};
+#define wf_to_lm75(c) container_of(c, struct wf_lm75_sensor, sens)
+#define i2c_to_lm75(c) container_of(c, struct wf_lm75_sensor, i2c)
+
+static int wf_lm75_attach(struct i2c_adapter *adapter);
+static int wf_lm75_detach(struct i2c_client *client);
+
+static struct i2c_driver wf_lm75_driver = {
+ .driver = {
+ .name = "wf_lm75",
+ },
+ .attach_adapter = wf_lm75_attach,
+ .detach_client = wf_lm75_detach,
+};
+
+static int wf_lm75_get(struct wf_sensor *sr, s32 *value)
+{
+ struct wf_lm75_sensor *lm = wf_to_lm75(sr);
+ s32 data;
+
+ if (lm->i2c.adapter == NULL)
+ return -ENODEV;
+
+ /* Init chip if necessary */
+ if (!lm->inited) {
+ u8 cfg_new, cfg = (u8)i2c_smbus_read_byte_data(&lm->i2c, 1);
+
+ DBG("wf_lm75: Initializing %s, cfg was: %02x\n",
+ sr->name, cfg);
+
+ /* clear shutdown bit, keep other settings as left by
+ * the firmware for now
+ */
+ cfg_new = cfg & ~0x01;
+ i2c_smbus_write_byte_data(&lm->i2c, 1, cfg_new);
+ lm->inited = 1;
+
+ /* If we just powered it up, let's wait 200 ms */
+ msleep(200);
+ }
+
+ /* Read temperature register */
+ data = (s32)le16_to_cpu(i2c_smbus_read_word_data(&lm->i2c, 0));
+ data <<= 8;
+ *value = data;
+
+ return 0;
+}
+
+static void wf_lm75_release(struct wf_sensor *sr)
+{
+ struct wf_lm75_sensor *lm = wf_to_lm75(sr);
+
+ /* check if client is registered and detach from i2c */
+ if (lm->i2c.adapter) {
+ i2c_detach_client(&lm->i2c);
+ lm->i2c.adapter = NULL;
+ }
+
+ kfree(lm);
+}
+
+static struct wf_sensor_ops wf_lm75_ops = {
+ .get_value = wf_lm75_get,
+ .release = wf_lm75_release,
+ .owner = THIS_MODULE,
+};
+
+static struct wf_lm75_sensor *wf_lm75_create(struct i2c_adapter *adapter,
+ u8 addr, int ds1775,
+ const char *loc)
+{
+ struct wf_lm75_sensor *lm;
+ int rc;
+
+ DBG("wf_lm75: creating %s device at address 0x%02x\n",
+ ds1775 ? "ds1775" : "lm75", addr);
+
+ lm = kmalloc(sizeof(struct wf_lm75_sensor), GFP_KERNEL);
+ if (lm == NULL)
+ return NULL;
+ memset(lm, 0, sizeof(struct wf_lm75_sensor));
+
+ /* Usual rant about sensor names not beeing very consistent in
+ * the device-tree, oh well ...
+ * Add more entries below as you deal with more setups
+ */
+ if (!strcmp(loc, "Hard drive") || !strcmp(loc, "DRIVE BAY"))
+ lm->sens.name = "hd-temp";
+ else
+ goto fail;
+
+ lm->inited = 0;
+ lm->sens.ops = &wf_lm75_ops;
+ lm->ds1775 = ds1775;
+ lm->i2c.addr = (addr >> 1) & 0x7f;
+ lm->i2c.adapter = adapter;
+ lm->i2c.driver = &wf_lm75_driver;
+ strncpy(lm->i2c.name, lm->sens.name, I2C_NAME_SIZE-1);
+
+ rc = i2c_attach_client(&lm->i2c);
+ if (rc) {
+ printk(KERN_ERR "windfarm: failed to attach %s %s to i2c,"
+ " err %d\n", ds1775 ? "ds1775" : "lm75",
+ lm->i2c.name, rc);
+ goto fail;
+ }
+
+ if (wf_register_sensor(&lm->sens)) {
+ i2c_detach_client(&lm->i2c);
+ goto fail;
+ }
+
+ return lm;
+ fail:
+ kfree(lm);
+ return NULL;
+}
+
+static int wf_lm75_attach(struct i2c_adapter *adapter)
+{
+ struct device_node *busnode, *dev;
+ struct pmac_i2c_bus *bus;
+
+ DBG("wf_lm75: adapter %s detected\n", adapter->name);
+
+ bus = pmac_i2c_adapter_to_bus(adapter);
+ if (bus == NULL)
+ return -ENODEV;
+ busnode = pmac_i2c_get_bus_node(bus);
+
+ DBG("wf_lm75: bus found, looking for device...\n");
+
+ /* Now look for lm75(s) in there */
+ for (dev = NULL;
+ (dev = of_get_next_child(busnode, dev)) != NULL;) {
+ const char *loc =
+ get_property(dev, "hwsensor-location", 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;
+ addr = pmac_i2c_get_dev_addr(dev);
+ if (loc == NULL || addr == 0)
+ continue;
+ /* real lm75 */
+ if (device_is_compatible(dev, "lm75"))
+ wf_lm75_create(adapter, addr, 0, loc);
+ /* ds1775 (compatible, better resolution */
+ else if (device_is_compatible(dev, "ds1775"))
+ wf_lm75_create(adapter, addr, 1, loc);
+ }
+ return 0;
+}
+
+static int wf_lm75_detach(struct i2c_client *client)
+{
+ struct wf_lm75_sensor *lm = i2c_to_lm75(client);
+
+ DBG("wf_lm75: i2c detatch called for %s\n", lm->sens.name);
+
+ /* Mark client detached */
+ lm->i2c.adapter = NULL;
+
+ /* release sensor */
+ wf_unregister_sensor(&lm->sens);
+
+ return 0;
+}
+
+static int __init wf_lm75_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_lm75_driver);
+}
+
+static void __exit wf_lm75_sensor_exit(void)
+{
+ i2c_del_driver(&wf_lm75_driver);
+}
+
+
+module_init(wf_lm75_sensor_init);
+module_exit(wf_lm75_sensor_exit);
+
+MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
+MODULE_DESCRIPTION("LM75 sensor objects for PowerMacs thermal control");
+MODULE_LICENSE("GPL");
+
git://git.onelab.eu / linux-2.6.git / blobdiff