/* * Windfarm PowerMac thermal control. SMU "satellite" controller sensors. * * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org> * * Released under the terms of the GNU GPL v2. */ #include <linux/types.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/slab.h> #include <linux/init.h> #include <linux/wait.h> #include <linux/i2c.h> #include <asm/semaphore.h> #include <asm/prom.h> #include <asm/smu.h> #include <asm/pmac_low_i2c.h> #include "windfarm.h" #define VERSION "0.2" #define DEBUG #ifdef DEBUG #define DBG(args...) printk(args) #else #define DBG(args...) do { } while(0) #endif /* If the cache is older than 800ms we'll refetch it */ #define MAX_AGE msecs_to_jiffies(800) struct wf_sat { int nr; atomic_t refcnt; struct semaphore mutex; unsigned long last_read; /* jiffies when cache last updated */ u8 cache[16]; struct i2c_client i2c; struct device_node *node; }; static struct wf_sat *sats[2]; struct wf_sat_sensor { int index; int index2; /* used for power sensors */ int shift; struct wf_sat *sat; struct wf_sensor sens; }; #define wf_to_sat(c) container_of(c, struct wf_sat_sensor, sens) #define i2c_to_sat(c) container_of(c, struct wf_sat, i2c) static int wf_sat_attach(struct i2c_adapter *adapter); static int wf_sat_detach(struct i2c_client *client); static struct i2c_driver wf_sat_driver = { .driver = { .name = "wf_smu_sat", }, .attach_adapter = wf_sat_attach, .detach_client = wf_sat_detach, }; /* * XXX i2c_smbus_read_i2c_block_data doesn't pass the requested * length down to the low-level driver, so we use this, which * works well enough with the SMU i2c driver code... */ static int sat_read_block(struct i2c_client *client, u8 command, u8 *values, int len) { union i2c_smbus_data data; int err; data.block[0] = len; err = i2c_smbus_xfer(client->adapter, client->addr, client->flags, I2C_SMBUS_READ, command, I2C_SMBUS_I2C_BLOCK_DATA, &data); if (!err) memcpy(values, data.block, len); return err; } struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id, unsigned int *size) { struct wf_sat *sat; int err; unsigned int i, len; u8 *buf; u8 data[4]; /* TODO: Add the resulting partition to the device-tree */ if (sat_id > 1 || (sat = sats[sat_id]) == NULL) return NULL; err = i2c_smbus_write_word_data(&sat->i2c, 8, id << 8); if (err) { printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err); return NULL; } len = i2c_smbus_read_word_data(&sat->i2c, 9); if (len < 0) { printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n"); return NULL; } if (len == 0) { printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id); return NULL; } len = le16_to_cpu(len); len = (len + 3) & ~3; buf = kmalloc(len, GFP_KERNEL); if (buf == NULL) return NULL; for (i = 0; i < len; i += 4) { err = sat_read_block(&sat->i2c, 0xa, data, 4); if (err) { printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n", err); goto fail; } buf[i] = data[1]; buf[i+1] = data[0]; buf[i+2] = data[3]; buf[i+3] = data[2]; } #ifdef DEBUG DBG(KERN_DEBUG "sat %d partition %x:", sat_id, id); for (i = 0; i < len; ++i) DBG(" %x", buf[i]); DBG("\n"); #endif if (size) *size = len; return (struct smu_sdbp_header *) buf; fail: kfree(buf); return NULL; } EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition); /* refresh the cache */ static int wf_sat_read_cache(struct wf_sat *sat) { int err; err = sat_read_block(&sat->i2c, 0x3f, sat->cache, 16); if (err) return err; sat->last_read = jiffies; #ifdef LOTSA_DEBUG { int i; DBG(KERN_DEBUG "wf_sat_get: data is"); for (i = 0; i < 16; ++i) DBG(" %.2x", sat->cache[i]); DBG("\n"); } #endif return 0; } static int wf_sat_get(struct wf_sensor *sr, s32 *value) { struct wf_sat_sensor *sens = wf_to_sat(sr); struct wf_sat *sat = sens->sat; int i, err; s32 val; if (sat->i2c.adapter == NULL) return -ENODEV; down(&sat->mutex); if (time_after(jiffies, (sat->last_read + MAX_AGE))) { err = wf_sat_read_cache(sat); if (err) goto fail; } i = sens->index * 2; val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift; if (sens->index2 >= 0) { i = sens->index2 * 2; /* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */ val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4; } *value = val; err = 0; fail: up(&sat->mutex); return err; } static void wf_sat_release(struct wf_sensor *sr) { struct wf_sat_sensor *sens = wf_to_sat(sr); struct wf_sat *sat = sens->sat; if (atomic_dec_and_test(&sat->refcnt)) { if (sat->i2c.adapter) { i2c_detach_client(&sat->i2c); sat->i2c.adapter = NULL; } if (sat->nr >= 0) sats[sat->nr] = NULL; kfree(sat); } kfree(sens); } static struct wf_sensor_ops wf_sat_ops = { .get_value = wf_sat_get, .release = wf_sat_release, .owner = THIS_MODULE, }; static void wf_sat_create(struct i2c_adapter *adapter, struct device_node *dev) { struct wf_sat *sat; struct wf_sat_sensor *sens; const u32 *reg; const char *loc, *type; u8 addr, chip, core; struct device_node *child; int shift, cpu, index; char *name; int vsens[2], isens[2]; reg = get_property(dev, "reg", NULL); if (reg == NULL) return; addr = *reg; DBG(KERN_DEBUG "wf_sat: creating sat at address %x\n", addr); sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL); if (sat == NULL) return; sat->nr = -1; sat->node = of_node_get(dev); atomic_set(&sat->refcnt, 0); init_MUTEX(&sat->mutex); sat->i2c.addr = (addr >> 1) & 0x7f; sat->i2c.adapter = adapter; sat->i2c.driver = &wf_sat_driver; strncpy(sat->i2c.name, "smu-sat", I2C_NAME_SIZE-1); if (i2c_attach_client(&sat->i2c)) { printk(KERN_ERR "windfarm: failed to attach smu-sat to i2c\n"); goto fail; } vsens[0] = vsens[1] = -1; isens[0] = isens[1] = -1; child = NULL; while ((child = of_get_next_child(dev, child)) != NULL) { reg = get_property(child, "reg", NULL); type = get_property(child, "device_type", NULL); loc = get_property(child, "location", NULL); if (reg == NULL || loc == NULL) continue; /* the cooked sensors are between 0x30 and 0x37 */ if (*reg < 0x30 || *reg > 0x37) continue; index = *reg - 0x30; /* expect location to be CPU [AB][01] ... */ if (strncmp(loc, "CPU ", 4) != 0) continue; chip = loc[4] - 'A'; core = loc[5] - '0'; if (chip > 1 || core > 1) { printk(KERN_ERR "wf_sat_create: don't understand " "location %s for %s\n", loc, child->full_name); continue; } cpu = 2 * chip + core; if (sat->nr < 0) sat->nr = chip; else if (sat->nr != chip) { printk(KERN_ERR "wf_sat_create: can't cope with " "multiple CPU chips on one SAT (%s)\n", loc); continue; } if (strcmp(type, "voltage-sensor") == 0) { name = "cpu-voltage"; shift = 4; vsens[core] = index; } else if (strcmp(type, "current-sensor") == 0) { name = "cpu-current"; shift = 8; isens[core] = index; } else if (strcmp(type, "temp-sensor") == 0) { name = "cpu-temp"; shift = 10; } else continue; /* hmmm shouldn't happen */ /* the +16 is enough for "cpu-voltage-n" */ sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); if (sens == NULL) { printk(KERN_ERR "wf_sat_create: couldn't create " "%s sensor %d (no memory)\n", name, cpu); continue; } sens->index = index; sens->index2 = -1; sens->shift = shift; sens->sat = sat; atomic_inc(&sat->refcnt); sens->sens.ops = &wf_sat_ops; sens->sens.name = (char *) (sens + 1); snprintf(sens->sens.name, 16, "%s-%d", name, cpu); if (wf_register_sensor(&sens->sens)) { atomic_dec(&sat->refcnt); kfree(sens); } } /* make the power sensors */ for (core = 0; core < 2; ++core) { if (vsens[core] < 0 || isens[core] < 0) continue; cpu = 2 * sat->nr + core; sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); if (sens == NULL) { printk(KERN_ERR "wf_sat_create: couldn't create power " "sensor %d (no memory)\n", cpu); continue; } sens->index = vsens[core]; sens->index2 = isens[core]; sens->shift = 0; sens->sat = sat; atomic_inc(&sat->refcnt); sens->sens.ops = &wf_sat_ops; sens->sens.name = (char *) (sens + 1); snprintf(sens->sens.name, 16, "cpu-power-%d", cpu); if (wf_register_sensor(&sens->sens)) { atomic_dec(&sat->refcnt); kfree(sens); } } if (sat->nr >= 0) sats[sat->nr] = sat; return; fail: kfree(sat); } static int wf_sat_attach(struct i2c_adapter *adapter) { struct device_node *busnode, *dev = NULL; struct pmac_i2c_bus *bus; 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) if (device_is_compatible(dev, "smu-sat")) wf_sat_create(adapter, dev); return 0; } static int wf_sat_detach(struct i2c_client *client) { struct wf_sat *sat = i2c_to_sat(client); /* XXX TODO */ sat->i2c.adapter = NULL; return 0; } static int __init sat_sensors_init(void) { return i2c_add_driver(&wf_sat_driver); } static void __exit sat_sensors_exit(void) { i2c_del_driver(&wf_sat_driver); } module_init(sat_sensors_init); /*module_exit(sat_sensors_exit); Uncomment when cleanup is implemented */ MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>"); MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control"); MODULE_LICENSE("GPL");