--- /dev/null
+/*
+ * 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;
+ 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");
git://git.onelab.eu / linux-2.6.git / blobdiff