mirror of
https://github.com/torvalds/linux.git
synced 2024-12-30 14:52:05 +00:00
436 lines
8.7 KiB
C
436 lines
8.7 KiB
C
/*
|
|
* linux/drivers/char/ds1620.c: Dallas Semiconductors DS1620
|
|
* thermometer driver (as used in the Rebel.com NetWinder)
|
|
*/
|
|
#include <linux/module.h>
|
|
#include <linux/miscdevice.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/proc_fs.h>
|
|
#include <linux/seq_file.h>
|
|
#include <linux/capability.h>
|
|
#include <linux/init.h>
|
|
#include <linux/mutex.h>
|
|
|
|
#include <mach/hardware.h>
|
|
#include <asm/mach-types.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm/therm.h>
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
/* define for /proc interface */
|
|
#define THERM_USE_PROC
|
|
#endif
|
|
|
|
/* Definitions for DS1620 chip */
|
|
#define THERM_START_CONVERT 0xee
|
|
#define THERM_RESET 0xaf
|
|
#define THERM_READ_CONFIG 0xac
|
|
#define THERM_READ_TEMP 0xaa
|
|
#define THERM_READ_TL 0xa2
|
|
#define THERM_READ_TH 0xa1
|
|
#define THERM_WRITE_CONFIG 0x0c
|
|
#define THERM_WRITE_TL 0x02
|
|
#define THERM_WRITE_TH 0x01
|
|
|
|
#define CFG_CPU 2
|
|
#define CFG_1SHOT 1
|
|
|
|
static DEFINE_MUTEX(ds1620_mutex);
|
|
static const char *fan_state[] = { "off", "on", "on (hardwired)" };
|
|
|
|
/*
|
|
* Start of NetWinder specifics
|
|
* Note! We have to hold the gpio lock with IRQs disabled over the
|
|
* whole of our transaction to the Dallas chip, since there is a
|
|
* chance that the WaveArtist driver could touch these bits to
|
|
* enable or disable the speaker.
|
|
*/
|
|
extern unsigned int system_rev;
|
|
|
|
static inline void netwinder_ds1620_set_clk(int clk)
|
|
{
|
|
nw_gpio_modify_op(GPIO_DSCLK, clk ? GPIO_DSCLK : 0);
|
|
}
|
|
|
|
static inline void netwinder_ds1620_set_data(int dat)
|
|
{
|
|
nw_gpio_modify_op(GPIO_DATA, dat ? GPIO_DATA : 0);
|
|
}
|
|
|
|
static inline int netwinder_ds1620_get_data(void)
|
|
{
|
|
return nw_gpio_read() & GPIO_DATA;
|
|
}
|
|
|
|
static inline void netwinder_ds1620_set_data_dir(int dir)
|
|
{
|
|
nw_gpio_modify_io(GPIO_DATA, dir ? GPIO_DATA : 0);
|
|
}
|
|
|
|
static inline void netwinder_ds1620_reset(void)
|
|
{
|
|
nw_cpld_modify(CPLD_DS_ENABLE, 0);
|
|
nw_cpld_modify(CPLD_DS_ENABLE, CPLD_DS_ENABLE);
|
|
}
|
|
|
|
static inline void netwinder_lock(unsigned long *flags)
|
|
{
|
|
raw_spin_lock_irqsave(&nw_gpio_lock, *flags);
|
|
}
|
|
|
|
static inline void netwinder_unlock(unsigned long *flags)
|
|
{
|
|
raw_spin_unlock_irqrestore(&nw_gpio_lock, *flags);
|
|
}
|
|
|
|
static inline void netwinder_set_fan(int i)
|
|
{
|
|
unsigned long flags;
|
|
|
|
raw_spin_lock_irqsave(&nw_gpio_lock, flags);
|
|
nw_gpio_modify_op(GPIO_FAN, i ? GPIO_FAN : 0);
|
|
raw_spin_unlock_irqrestore(&nw_gpio_lock, flags);
|
|
}
|
|
|
|
static inline int netwinder_get_fan(void)
|
|
{
|
|
if ((system_rev & 0xf000) == 0x4000)
|
|
return FAN_ALWAYS_ON;
|
|
|
|
return (nw_gpio_read() & GPIO_FAN) ? FAN_ON : FAN_OFF;
|
|
}
|
|
|
|
/*
|
|
* End of NetWinder specifics
|
|
*/
|
|
|
|
static void ds1620_send_bits(int nr, int value)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < nr; i++) {
|
|
netwinder_ds1620_set_data(value & 1);
|
|
netwinder_ds1620_set_clk(0);
|
|
udelay(1);
|
|
netwinder_ds1620_set_clk(1);
|
|
udelay(1);
|
|
|
|
value >>= 1;
|
|
}
|
|
}
|
|
|
|
static unsigned int ds1620_recv_bits(int nr)
|
|
{
|
|
unsigned int value = 0, mask = 1;
|
|
int i;
|
|
|
|
netwinder_ds1620_set_data(0);
|
|
|
|
for (i = 0; i < nr; i++) {
|
|
netwinder_ds1620_set_clk(0);
|
|
udelay(1);
|
|
|
|
if (netwinder_ds1620_get_data())
|
|
value |= mask;
|
|
|
|
mask <<= 1;
|
|
|
|
netwinder_ds1620_set_clk(1);
|
|
udelay(1);
|
|
}
|
|
|
|
return value;
|
|
}
|
|
|
|
static void ds1620_out(int cmd, int bits, int value)
|
|
{
|
|
unsigned long flags;
|
|
|
|
netwinder_lock(&flags);
|
|
netwinder_ds1620_set_clk(1);
|
|
netwinder_ds1620_set_data_dir(0);
|
|
netwinder_ds1620_reset();
|
|
|
|
udelay(1);
|
|
|
|
ds1620_send_bits(8, cmd);
|
|
if (bits)
|
|
ds1620_send_bits(bits, value);
|
|
|
|
udelay(1);
|
|
|
|
netwinder_ds1620_reset();
|
|
netwinder_unlock(&flags);
|
|
|
|
msleep(20);
|
|
}
|
|
|
|
static unsigned int ds1620_in(int cmd, int bits)
|
|
{
|
|
unsigned long flags;
|
|
unsigned int value;
|
|
|
|
netwinder_lock(&flags);
|
|
netwinder_ds1620_set_clk(1);
|
|
netwinder_ds1620_set_data_dir(0);
|
|
netwinder_ds1620_reset();
|
|
|
|
udelay(1);
|
|
|
|
ds1620_send_bits(8, cmd);
|
|
|
|
netwinder_ds1620_set_data_dir(1);
|
|
value = ds1620_recv_bits(bits);
|
|
|
|
netwinder_ds1620_reset();
|
|
netwinder_unlock(&flags);
|
|
|
|
return value;
|
|
}
|
|
|
|
static int cvt_9_to_int(unsigned int val)
|
|
{
|
|
if (val & 0x100)
|
|
val |= 0xfffffe00;
|
|
|
|
return val;
|
|
}
|
|
|
|
static void ds1620_write_state(struct therm *therm)
|
|
{
|
|
ds1620_out(THERM_WRITE_CONFIG, 8, CFG_CPU);
|
|
ds1620_out(THERM_WRITE_TL, 9, therm->lo);
|
|
ds1620_out(THERM_WRITE_TH, 9, therm->hi);
|
|
ds1620_out(THERM_START_CONVERT, 0, 0);
|
|
}
|
|
|
|
static void ds1620_read_state(struct therm *therm)
|
|
{
|
|
therm->lo = cvt_9_to_int(ds1620_in(THERM_READ_TL, 9));
|
|
therm->hi = cvt_9_to_int(ds1620_in(THERM_READ_TH, 9));
|
|
}
|
|
|
|
static int ds1620_open(struct inode *inode, struct file *file)
|
|
{
|
|
return nonseekable_open(inode, file);
|
|
}
|
|
|
|
static ssize_t
|
|
ds1620_read(struct file *file, char __user *buf, size_t count, loff_t *ptr)
|
|
{
|
|
signed int cur_temp;
|
|
signed char cur_temp_degF;
|
|
|
|
cur_temp = cvt_9_to_int(ds1620_in(THERM_READ_TEMP, 9)) >> 1;
|
|
|
|
/* convert to Fahrenheit, as per wdt.c */
|
|
cur_temp_degF = (cur_temp * 9) / 5 + 32;
|
|
|
|
if (copy_to_user(buf, &cur_temp_degF, 1))
|
|
return -EFAULT;
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int
|
|
ds1620_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
|
|
{
|
|
struct therm therm;
|
|
union {
|
|
struct therm __user *therm;
|
|
int __user *i;
|
|
} uarg;
|
|
int i;
|
|
|
|
uarg.i = (int __user *)arg;
|
|
|
|
switch(cmd) {
|
|
case CMD_SET_THERMOSTATE:
|
|
case CMD_SET_THERMOSTATE2:
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
if (cmd == CMD_SET_THERMOSTATE) {
|
|
if (get_user(therm.hi, uarg.i))
|
|
return -EFAULT;
|
|
therm.lo = therm.hi - 3;
|
|
} else {
|
|
if (copy_from_user(&therm, uarg.therm, sizeof(therm)))
|
|
return -EFAULT;
|
|
}
|
|
|
|
therm.lo <<= 1;
|
|
therm.hi <<= 1;
|
|
|
|
ds1620_write_state(&therm);
|
|
break;
|
|
|
|
case CMD_GET_THERMOSTATE:
|
|
case CMD_GET_THERMOSTATE2:
|
|
ds1620_read_state(&therm);
|
|
|
|
therm.lo >>= 1;
|
|
therm.hi >>= 1;
|
|
|
|
if (cmd == CMD_GET_THERMOSTATE) {
|
|
if (put_user(therm.hi, uarg.i))
|
|
return -EFAULT;
|
|
} else {
|
|
if (copy_to_user(uarg.therm, &therm, sizeof(therm)))
|
|
return -EFAULT;
|
|
}
|
|
break;
|
|
|
|
case CMD_GET_TEMPERATURE:
|
|
case CMD_GET_TEMPERATURE2:
|
|
i = cvt_9_to_int(ds1620_in(THERM_READ_TEMP, 9));
|
|
|
|
if (cmd == CMD_GET_TEMPERATURE)
|
|
i >>= 1;
|
|
|
|
return put_user(i, uarg.i) ? -EFAULT : 0;
|
|
|
|
case CMD_GET_STATUS:
|
|
i = ds1620_in(THERM_READ_CONFIG, 8) & 0xe3;
|
|
|
|
return put_user(i, uarg.i) ? -EFAULT : 0;
|
|
|
|
case CMD_GET_FAN:
|
|
i = netwinder_get_fan();
|
|
|
|
return put_user(i, uarg.i) ? -EFAULT : 0;
|
|
|
|
case CMD_SET_FAN:
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
if (get_user(i, uarg.i))
|
|
return -EFAULT;
|
|
|
|
netwinder_set_fan(i);
|
|
break;
|
|
|
|
default:
|
|
return -ENOIOCTLCMD;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static long
|
|
ds1620_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
|
|
{
|
|
int ret;
|
|
|
|
mutex_lock(&ds1620_mutex);
|
|
ret = ds1620_ioctl(file, cmd, arg);
|
|
mutex_unlock(&ds1620_mutex);
|
|
|
|
return ret;
|
|
}
|
|
|
|
#ifdef THERM_USE_PROC
|
|
static int ds1620_proc_therm_show(struct seq_file *m, void *v)
|
|
{
|
|
struct therm th;
|
|
int temp;
|
|
|
|
ds1620_read_state(&th);
|
|
temp = cvt_9_to_int(ds1620_in(THERM_READ_TEMP, 9));
|
|
|
|
seq_printf(m, "Thermostat: HI %i.%i, LOW %i.%i; temperature: %i.%i C, fan %s\n",
|
|
th.hi >> 1, th.hi & 1 ? 5 : 0,
|
|
th.lo >> 1, th.lo & 1 ? 5 : 0,
|
|
temp >> 1, temp & 1 ? 5 : 0,
|
|
fan_state[netwinder_get_fan()]);
|
|
return 0;
|
|
}
|
|
|
|
static int ds1620_proc_therm_open(struct inode *inode, struct file *file)
|
|
{
|
|
return single_open(file, ds1620_proc_therm_show, NULL);
|
|
}
|
|
|
|
static const struct file_operations ds1620_proc_therm_fops = {
|
|
.open = ds1620_proc_therm_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = single_release,
|
|
};
|
|
#endif
|
|
|
|
static const struct file_operations ds1620_fops = {
|
|
.owner = THIS_MODULE,
|
|
.open = ds1620_open,
|
|
.read = ds1620_read,
|
|
.unlocked_ioctl = ds1620_unlocked_ioctl,
|
|
.llseek = no_llseek,
|
|
};
|
|
|
|
static struct miscdevice ds1620_miscdev = {
|
|
TEMP_MINOR,
|
|
"temp",
|
|
&ds1620_fops
|
|
};
|
|
|
|
static int __init ds1620_init(void)
|
|
{
|
|
int ret;
|
|
struct therm th, th_start;
|
|
|
|
if (!machine_is_netwinder())
|
|
return -ENODEV;
|
|
|
|
ds1620_out(THERM_RESET, 0, 0);
|
|
ds1620_out(THERM_WRITE_CONFIG, 8, CFG_CPU);
|
|
ds1620_out(THERM_START_CONVERT, 0, 0);
|
|
|
|
/*
|
|
* Trigger the fan to start by setting
|
|
* temperature high point low. This kicks
|
|
* the fan into action.
|
|
*/
|
|
ds1620_read_state(&th);
|
|
th_start.lo = 0;
|
|
th_start.hi = 1;
|
|
ds1620_write_state(&th_start);
|
|
|
|
msleep(2000);
|
|
|
|
ds1620_write_state(&th);
|
|
|
|
ret = misc_register(&ds1620_miscdev);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
#ifdef THERM_USE_PROC
|
|
if (!proc_create("therm", 0, NULL, &ds1620_proc_therm_fops))
|
|
printk(KERN_ERR "therm: unable to register /proc/therm\n");
|
|
#endif
|
|
|
|
ds1620_read_state(&th);
|
|
ret = cvt_9_to_int(ds1620_in(THERM_READ_TEMP, 9));
|
|
|
|
printk(KERN_INFO "Thermostat: high %i.%i, low %i.%i, "
|
|
"current %i.%i C, fan %s.\n",
|
|
th.hi >> 1, th.hi & 1 ? 5 : 0,
|
|
th.lo >> 1, th.lo & 1 ? 5 : 0,
|
|
ret >> 1, ret & 1 ? 5 : 0,
|
|
fan_state[netwinder_get_fan()]);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __exit ds1620_exit(void)
|
|
{
|
|
#ifdef THERM_USE_PROC
|
|
remove_proc_entry("therm", NULL);
|
|
#endif
|
|
misc_deregister(&ds1620_miscdev);
|
|
}
|
|
|
|
module_init(ds1620_init);
|
|
module_exit(ds1620_exit);
|
|
|
|
MODULE_LICENSE("GPL");
|