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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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 | /* * Windfarm PowerMac thermal control. LM87 sensor * * Copyright 2012 Benjamin Herrenschmidt, IBM Corp. * * 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/sections.h> #include <asm/pmac_low_i2c.h> #include "windfarm.h" #define VERSION "1.0" #undef DEBUG #ifdef DEBUG #define DBG(args...) printk(args) #else #define DBG(args...) do { } while(0) #endif struct wf_lm87_sensor { struct i2c_client *i2c; struct wf_sensor sens; }; #define wf_to_lm87(c) container_of(c, struct wf_lm87_sensor, sens) static int wf_lm87_read_reg(struct i2c_client *chip, int reg) { int rc, tries = 0; u8 buf; for (;;) { /* Set address */ buf = (u8)reg; rc = i2c_master_send(chip, &buf, 1); if (rc <= 0) goto error; rc = i2c_master_recv(chip, &buf, 1); if (rc <= 0) goto error; return (int)buf; error: DBG("wf_lm87: Error reading LM87, retrying...\n"); if (++tries > 10) { printk(KERN_ERR "wf_lm87: Error reading LM87 !\n"); return -EIO; } msleep(10); } } static int wf_lm87_get(struct wf_sensor *sr, s32 *value) { struct wf_lm87_sensor *lm = sr->priv; s32 temp; if (lm->i2c == NULL) return -ENODEV; #define LM87_INT_TEMP 0x27 /* Read temperature register */ temp = wf_lm87_read_reg(lm->i2c, LM87_INT_TEMP); if (temp < 0) return temp; *value = temp << 16; return 0; } static void wf_lm87_release(struct wf_sensor *sr) { struct wf_lm87_sensor *lm = wf_to_lm87(sr); kfree(lm); } static struct wf_sensor_ops wf_lm87_ops = { .get_value = wf_lm87_get, .release = wf_lm87_release, .owner = THIS_MODULE, }; static int wf_lm87_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct wf_lm87_sensor *lm; const char *name = NULL, *loc; struct device_node *np = NULL; int rc; /* * The lm87 contains a whole pile of sensors, additionally, * the Xserve G5 has several lm87's. However, for now we only * care about the internal temperature sensor */ while ((np = of_get_next_child(client->dev.of_node, np)) != NULL) { if (strcmp(np->name, "int-temp")) continue; loc = of_get_property(np, "location", NULL); if (!loc) continue; if (strstr(loc, "DIMM")) name = "dimms-temp"; else if (strstr(loc, "Processors")) name = "between-cpus-temp"; if (name) { of_node_put(np); break; } } if (!name) { pr_warning("wf_lm87: Unsupported sensor %s\n", client->dev.of_node->full_name); return -ENODEV; } lm = kzalloc(sizeof(struct wf_lm87_sensor), GFP_KERNEL); if (lm == NULL) return -ENODEV; lm->i2c = client; lm->sens.name = name; lm->sens.ops = &wf_lm87_ops; lm->sens.priv = lm; i2c_set_clientdata(client, lm); rc = wf_register_sensor(&lm->sens); if (rc) kfree(lm); return rc; } static int wf_lm87_remove(struct i2c_client *client) { struct wf_lm87_sensor *lm = i2c_get_clientdata(client); DBG("wf_lm87: i2c detatch called for %s\n", lm->sens.name); /* Mark client detached */ lm->i2c = NULL; /* release sensor */ wf_unregister_sensor(&lm->sens); return 0; } static const struct i2c_device_id wf_lm87_id[] = { { "MAC,lm87cimt", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, wf_lm87_id); static struct i2c_driver wf_lm87_driver = { .driver = { .name = "wf_lm87", }, .probe = wf_lm87_probe, .remove = wf_lm87_remove, .id_table = wf_lm87_id, }; static int __init wf_lm87_sensor_init(void) { /* We only support this on the Xserve */ if (!of_machine_is_compatible("RackMac3,1")) return -ENODEV; return i2c_add_driver(&wf_lm87_driver); } static void __exit wf_lm87_sensor_exit(void) { i2c_del_driver(&wf_lm87_driver); } module_init(wf_lm87_sensor_init); module_exit(wf_lm87_sensor_exit); MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); MODULE_DESCRIPTION("LM87 sensor objects for PowerMacs thermal control"); MODULE_LICENSE("GPL"); |