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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 | /* * 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"); |