diff options
Diffstat (limited to 'drivers/macintosh/windfarm_lm75_sensor.c')
| -rw-r--r-- | drivers/macintosh/windfarm_lm75_sensor.c | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/drivers/macintosh/windfarm_lm75_sensor.c b/drivers/macintosh/windfarm_lm75_sensor.c new file mode 100644 index 000000000..9dd80837a --- /dev/null +++ b/drivers/macintosh/windfarm_lm75_sensor.c @@ -0,0 +1,190 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Windfarm PowerMac thermal control. LM75 sensor + * + * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp. + * <benh@kernel.crashing.org> + */ + +#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 <linux/of_device.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_lm75_sensor { + unsigned int ds1775 : 1; + unsigned int inited : 1; + struct i2c_client *i2c; + struct wf_sensor sens; +}; +#define wf_to_lm75(c) container_of(c, struct wf_lm75_sensor, sens) + +static int wf_lm75_get(struct wf_sensor *sr, s32 *value) +{ + struct wf_lm75_sensor *lm = wf_to_lm75(sr); + s32 data; + + if (lm->i2c == NULL) + return -ENODEV; + + /* Init chip if necessary */ + if (!lm->inited) { + u8 cfg_new, cfg = (u8)i2c_smbus_read_byte_data(lm->i2c, 1); + + DBG("wf_lm75: Initializing %s, cfg was: %02x\n", + sr->name, cfg); + + /* clear shutdown bit, keep other settings as left by + * the firmware for now + */ + cfg_new = cfg & ~0x01; + i2c_smbus_write_byte_data(lm->i2c, 1, cfg_new); + lm->inited = 1; + + /* If we just powered it up, let's wait 200 ms */ + msleep(200); + } + + /* Read temperature register */ + data = (s32)le16_to_cpu(i2c_smbus_read_word_data(lm->i2c, 0)); + data <<= 8; + *value = data; + + return 0; +} + +static void wf_lm75_release(struct wf_sensor *sr) +{ + struct wf_lm75_sensor *lm = wf_to_lm75(sr); + + kfree(lm); +} + +static const struct wf_sensor_ops wf_lm75_ops = { + .get_value = wf_lm75_get, + .release = wf_lm75_release, + .owner = THIS_MODULE, +}; + +static int wf_lm75_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct wf_lm75_sensor *lm; + int rc, ds1775; + const char *name, *loc; + + if (id) + ds1775 = id->driver_data; + else + ds1775 = !!of_device_get_match_data(&client->dev); + + DBG("wf_lm75: creating %s device at address 0x%02x\n", + ds1775 ? "ds1775" : "lm75", client->addr); + + loc = of_get_property(client->dev.of_node, "hwsensor-location", NULL); + if (!loc) { + dev_warn(&client->dev, "Missing hwsensor-location property!\n"); + return -ENXIO; + } + + /* Usual rant about sensor names not beeing very consistent in + * the device-tree, oh well ... + * Add more entries below as you deal with more setups + */ + if (!strcmp(loc, "Hard drive") || !strcmp(loc, "DRIVE BAY")) + name = "hd-temp"; + else if (!strcmp(loc, "Incoming Air Temp")) + name = "incoming-air-temp"; + else if (!strcmp(loc, "ODD Temp")) + name = "optical-drive-temp"; + else if (!strcmp(loc, "HD Temp")) + name = "hard-drive-temp"; + else if (!strcmp(loc, "PCI SLOTS")) + name = "slots-temp"; + else if (!strcmp(loc, "CPU A INLET")) + name = "cpu-inlet-temp-0"; + else if (!strcmp(loc, "CPU B INLET")) + name = "cpu-inlet-temp-1"; + else + return -ENXIO; + + + lm = kzalloc(sizeof(struct wf_lm75_sensor), GFP_KERNEL); + if (lm == NULL) + return -ENODEV; + + lm->inited = 0; + lm->ds1775 = ds1775; + lm->i2c = client; + lm->sens.name = name; + lm->sens.ops = &wf_lm75_ops; + i2c_set_clientdata(client, lm); + + rc = wf_register_sensor(&lm->sens); + if (rc) + kfree(lm); + return rc; +} + +static void wf_lm75_remove(struct i2c_client *client) +{ + struct wf_lm75_sensor *lm = i2c_get_clientdata(client); + + /* Mark client detached */ + lm->i2c = NULL; + + /* release sensor */ + wf_unregister_sensor(&lm->sens); +} + +static const struct i2c_device_id wf_lm75_id[] = { + { "MAC,lm75", 0 }, + { "MAC,ds1775", 1 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, wf_lm75_id); + +static const struct of_device_id wf_lm75_of_id[] = { + { .compatible = "lm75", .data = (void *)0}, + { .compatible = "ds1775", .data = (void *)1 }, + { } +}; +MODULE_DEVICE_TABLE(of, wf_lm75_of_id); + +static struct i2c_driver wf_lm75_driver = { + .driver = { + .name = "wf_lm75", + .of_match_table = wf_lm75_of_id, + }, + .probe = wf_lm75_probe, + .remove = wf_lm75_remove, + .id_table = wf_lm75_id, +}; + +module_i2c_driver(wf_lm75_driver); + +MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); +MODULE_DESCRIPTION("LM75 sensor objects for PowerMacs thermal control"); +MODULE_LICENSE("GPL"); + |