diff options
Diffstat (limited to 'drivers/macintosh/windfarm_smu_sat.c')
-rw-r--r-- | drivers/macintosh/windfarm_smu_sat.c | 419 |
1 files changed, 419 insertions, 0 deletions
diff --git a/drivers/macintosh/windfarm_smu_sat.c b/drivers/macintosh/windfarm_smu_sat.c new file mode 100644 index 00000000000..24e51d5e97f --- /dev/null +++ b/drivers/macintosh/windfarm_smu_sat.c @@ -0,0 +1,419 @@ +/* + * 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 <linux/i2c-dev.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; + u32 *reg; + char *loc, *type; + u8 addr, chip, core; + struct device_node *child; + int shift, cpu, index; + char *name; + int vsens[2], isens[2]; + + reg = (u32 *) 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 = (u32 *) 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) +{ + int err; + + err = i2c_add_driver(&wf_sat_driver); + if (err < 0) + return err; + return 0; +} + +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"); |