[linux.git] / drivers / char / ds1620.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 <linux/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;
}
#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_single("therm", 0, NULL, ds1620_proc_therm_show))
		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");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/drivers/char/ds1620.c: Dallas Semiconductors DS1620
	3	* thermometer driver (as used in the Rebel.com NetWinder)
	4	*/
1da177e4	5	#include <linux/module.h>
1da177e4	6	#include <linux/miscdevice.h>
1da177e4 LT	7	#include <linux/delay.h>
1da177e4 LT	8	#include <linux/proc_fs.h>
9fb8ca5c	9	#include <linux/seq_file.h>
1da177e4 LT	10	#include <linux/capability.h>
1da177e4 LT	11	#include <linux/init.h>
613655fa	12	#include <linux/mutex.h>
1da177e4	13
a09e64fb	14	#include <mach/hardware.h>
1da177e4	15	#include <asm/mach-types.h>
7c0f6ba6	16	#include <linux/uaccess.h>
1da177e4 LT	17	#include <asm/therm.h>
	18
	19	#ifdef CONFIG_PROC_FS
	20	/* define for /proc interface */
	21	#define THERM_USE_PROC
	22	#endif
	23
	24	/* Definitions for DS1620 chip */
	25	#define THERM_START_CONVERT 0xee
	26	#define THERM_RESET 0xaf
	27	#define THERM_READ_CONFIG 0xac
	28	#define THERM_READ_TEMP 0xaa
	29	#define THERM_READ_TL 0xa2
	30	#define THERM_READ_TH 0xa1
	31	#define THERM_WRITE_CONFIG 0x0c
	32	#define THERM_WRITE_TL 0x02
	33	#define THERM_WRITE_TH 0x01
	34
	35	#define CFG_CPU 2
	36	#define CFG_1SHOT 1
	37
613655fa	38	static DEFINE_MUTEX(ds1620_mutex);
1da177e4 LT	39	static const char *fan_state[] = { "off", "on", "on (hardwired)" };
	40
	41	/*
	42	* Start of NetWinder specifics
	43	* Note! We have to hold the gpio lock with IRQs disabled over the
	44	* whole of our transaction to the Dallas chip, since there is a
	45	* chance that the WaveArtist driver could touch these bits to
	46	* enable or disable the speaker.
	47	*/
1da177e4 LT	48	extern unsigned int system_rev;
	49
	50	static inline void netwinder_ds1620_set_clk(int clk)
	51	{
70d13e08	52	nw_gpio_modify_op(GPIO_DSCLK, clk ? GPIO_DSCLK : 0);
1da177e4 LT	53	}
	54
	55	static inline void netwinder_ds1620_set_data(int dat)
	56	{
70d13e08	57	nw_gpio_modify_op(GPIO_DATA, dat ? GPIO_DATA : 0);
1da177e4 LT	58	}
	59
	60	static inline int netwinder_ds1620_get_data(void)
	61	{
70d13e08	62	return nw_gpio_read() & GPIO_DATA;
1da177e4 LT	63	}
	64
	65	static inline void netwinder_ds1620_set_data_dir(int dir)
	66	{
70d13e08	67	nw_gpio_modify_io(GPIO_DATA, dir ? GPIO_DATA : 0);
1da177e4 LT	68	}
	69
	70	static inline void netwinder_ds1620_reset(void)
	71	{
70d13e08 RK	72	nw_cpld_modify(CPLD_DS_ENABLE, 0);
70d13e08 RK	73	nw_cpld_modify(CPLD_DS_ENABLE, CPLD_DS_ENABLE);
1da177e4 LT	74	}
	75
	76	static inline void netwinder_lock(unsigned long *flags)
	77	{
45ef6ac6	78	raw_spin_lock_irqsave(&nw_gpio_lock, *flags);
1da177e4 LT	79	}
	80
	81	static inline void netwinder_unlock(unsigned long *flags)
	82	{
45ef6ac6	83	raw_spin_unlock_irqrestore(&nw_gpio_lock, *flags);
1da177e4 LT	84	}
	85
	86	static inline void netwinder_set_fan(int i)
	87	{
	88	unsigned long flags;
	89
45ef6ac6	90	raw_spin_lock_irqsave(&nw_gpio_lock, flags);
70d13e08	91	nw_gpio_modify_op(GPIO_FAN, i ? GPIO_FAN : 0);
45ef6ac6	92	raw_spin_unlock_irqrestore(&nw_gpio_lock, flags);
1da177e4 LT	93	}
	94
	95	static inline int netwinder_get_fan(void)
	96	{
	97	if ((system_rev & 0xf000) == 0x4000)
	98	return FAN_ALWAYS_ON;
	99
70d13e08	100	return (nw_gpio_read() & GPIO_FAN) ? FAN_ON : FAN_OFF;
1da177e4 LT	101	}
	102
	103	/*
	104	* End of NetWinder specifics
	105	*/
	106
	107	static void ds1620_send_bits(int nr, int value)
	108	{
	109	int i;
	110
	111	for (i = 0; i < nr; i++) {
	112	netwinder_ds1620_set_data(value & 1);
	113	netwinder_ds1620_set_clk(0);
	114	udelay(1);
	115	netwinder_ds1620_set_clk(1);
	116	udelay(1);
	117
	118	value >>= 1;
	119	}
	120	}
	121
	122	static unsigned int ds1620_recv_bits(int nr)
	123	{
	124	unsigned int value = 0, mask = 1;
	125	int i;
	126
	127	netwinder_ds1620_set_data(0);
	128
	129	for (i = 0; i < nr; i++) {
	130	netwinder_ds1620_set_clk(0);
	131	udelay(1);
	132
	133	if (netwinder_ds1620_get_data())
	134	value \|= mask;
	135
	136	mask <<= 1;
	137
	138	netwinder_ds1620_set_clk(1);
	139	udelay(1);
	140	}
	141
	142	return value;
	143	}
	144
	145	static void ds1620_out(int cmd, int bits, int value)
	146	{
	147	unsigned long flags;
	148
	149	netwinder_lock(&flags);
	150	netwinder_ds1620_set_clk(1);
	151	netwinder_ds1620_set_data_dir(0);
	152	netwinder_ds1620_reset();
	153
	154	udelay(1);
	155
	156	ds1620_send_bits(8, cmd);
	157	if (bits)
	158	ds1620_send_bits(bits, value);
	159
	160	udelay(1);
	161
	162	netwinder_ds1620_reset();
	163	netwinder_unlock(&flags);
	164
d8eddb62	165	msleep(20);
1da177e4 LT	166	}
	167
	168	static unsigned int ds1620_in(int cmd, int bits)
	169	{
	170	unsigned long flags;
	171	unsigned int value;
	172
	173	netwinder_lock(&flags);
	174	netwinder_ds1620_set_clk(1);
	175	netwinder_ds1620_set_data_dir(0);
	176	netwinder_ds1620_reset();
	177
	178	udelay(1);
	179
	180	ds1620_send_bits(8, cmd);
	181
	182	netwinder_ds1620_set_data_dir(1);
	183	value = ds1620_recv_bits(bits);
	184
	185	netwinder_ds1620_reset();
	186	netwinder_unlock(&flags);
	187
	188	return value;
	189	}
	190
	191	static int cvt_9_to_int(unsigned int val)
	192	{
	193	if (val & 0x100)
	194	val \|= 0xfffffe00;
	195
	196	return val;
	197	}
	198
	199	static void ds1620_write_state(struct therm *therm)
	200	{
	201	ds1620_out(THERM_WRITE_CONFIG, 8, CFG_CPU);
	202	ds1620_out(THERM_WRITE_TL, 9, therm->lo);
	203	ds1620_out(THERM_WRITE_TH, 9, therm->hi);
	204	ds1620_out(THERM_START_CONVERT, 0, 0);
	205	}
	206
	207	static void ds1620_read_state(struct therm *therm)
	208	{
	209	therm->lo = cvt_9_to_int(ds1620_in(THERM_READ_TL, 9));
	210	therm->hi = cvt_9_to_int(ds1620_in(THERM_READ_TH, 9));
	211	}
	212
080c2226 AB	213	static int ds1620_open(struct inode inode, struct file file)
080c2226 AB	214	{
080c2226 AB	215	return nonseekable_open(inode, file);
	216	}
	217
1da177e4 LT	218	static ssize_t
	219	ds1620_read(struct file file, char __user buf, size_t count, loff_t *ptr)
	220	{
	221	signed int cur_temp;
	222	signed char cur_temp_degF;
	223
	224	cur_temp = cvt_9_to_int(ds1620_in(THERM_READ_TEMP, 9)) >> 1;
	225
	226	/* convert to Fahrenheit, as per wdt.c */
	227	cur_temp_degF = (cur_temp * 9) / 5 + 32;
	228
	229	if (copy_to_user(buf, &cur_temp_degF, 1))
	230	return -EFAULT;
	231
	232	return 1;
	233	}
	234
	235	static int
55929332	236	ds1620_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1da177e4 LT	237	{
	238	struct therm therm;
	239	union {
	240	struct therm __user *therm;
	241	int __user *i;
	242	} uarg;
	243	int i;
	244
	245	uarg.i = (int __user *)arg;
	246
	247	switch(cmd) {
	248	case CMD_SET_THERMOSTATE:
	249	case CMD_SET_THERMOSTATE2:
	250	if (!capable(CAP_SYS_ADMIN))
	251	return -EPERM;
	252
	253	if (cmd == CMD_SET_THERMOSTATE) {
	254	if (get_user(therm.hi, uarg.i))
	255	return -EFAULT;
	256	therm.lo = therm.hi - 3;
	257	} else {
	258	if (copy_from_user(&therm, uarg.therm, sizeof(therm)))
	259	return -EFAULT;
	260	}
	261
	262	therm.lo <<= 1;
	263	therm.hi <<= 1;
	264
	265	ds1620_write_state(&therm);
	266	break;
	267
	268	case CMD_GET_THERMOSTATE:
	269	case CMD_GET_THERMOSTATE2:
	270	ds1620_read_state(&therm);
	271
	272	therm.lo >>= 1;
	273	therm.hi >>= 1;
	274
	275	if (cmd == CMD_GET_THERMOSTATE) {
	276	if (put_user(therm.hi, uarg.i))
	277	return -EFAULT;
	278	} else {
	279	if (copy_to_user(uarg.therm, &therm, sizeof(therm)))
	280	return -EFAULT;
	281	}
	282	break;
	283
	284	case CMD_GET_TEMPERATURE:
	285	case CMD_GET_TEMPERATURE2:
	286	i = cvt_9_to_int(ds1620_in(THERM_READ_TEMP, 9));
	287
	288	if (cmd == CMD_GET_TEMPERATURE)
	289	i >>= 1;
	290
	291	return put_user(i, uarg.i) ? -EFAULT : 0;
	292
	293	case CMD_GET_STATUS:
	294	i = ds1620_in(THERM_READ_CONFIG, 8) & 0xe3;
	295
	296	return put_user(i, uarg.i) ? -EFAULT : 0;
	297
	298	case CMD_GET_FAN:
	299	i = netwinder_get_fan();
	300
301	return put_user(i, uarg.i) ? -EFAULT : 0;
302
303	case CMD_SET_FAN:
304	if (!capable(CAP_SYS_ADMIN))
305	return -EPERM;
306
307	if (get_user(i, uarg.i))
308	return -EFAULT;
309
310	netwinder_set_fan(i);
311	break;
312
313	default:
314	return -ENOIOCTLCMD;
315	}
316
317	return 0;
318	}
319
55929332 AB	320	static long
	321	ds1620_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	322	{
	323	int ret;
	324
613655fa	325	mutex_lock(&ds1620_mutex);
55929332	326	ret = ds1620_ioctl(file, cmd, arg);
613655fa	327	mutex_unlock(&ds1620_mutex);
55929332 AB	328
	329	return ret;
	330	}
	331
1da177e4	332	#ifdef THERM_USE_PROC
9fb8ca5c	333	static int ds1620_proc_therm_show(struct seq_file m, void v)
1da177e4 LT	334	{
	335	struct therm th;
	336	int temp;
	337
	338	ds1620_read_state(&th);
	339	temp = cvt_9_to_int(ds1620_in(THERM_READ_TEMP, 9));
	340
9fb8ca5c DH	341	seq_printf(m, "Thermostat: HI %i.%i, LOW %i.%i; temperature: %i.%i C, fan %s\n",
	342	th.hi >> 1, th.hi & 1 ? 5 : 0,
	343	th.lo >> 1, th.lo & 1 ? 5 : 0,
	344	temp >> 1, temp & 1 ? 5 : 0,
	345	fan_state[netwinder_get_fan()]);
	346	return 0;
	347	}
1da177e4 LT	348	#endif
1da177e4 LT	349
62322d25	350	static const struct file_operations ds1620_fops = {
1da177e4	351	.owner = THIS_MODULE,
080c2226	352	.open = ds1620_open,
1da177e4	353	.read = ds1620_read,
55929332	354	.unlocked_ioctl = ds1620_unlocked_ioctl,
6038f373	355	.llseek = no_llseek,
1da177e4 LT	356	};
	357
	358	static struct miscdevice ds1620_miscdev = {
	359	TEMP_MINOR,
	360	"temp",
	361	&ds1620_fops
	362	};
	363
	364	static int __init ds1620_init(void)
	365	{
	366	int ret;
	367	struct therm th, th_start;
	368
	369	if (!machine_is_netwinder())
	370	return -ENODEV;
	371
	372	ds1620_out(THERM_RESET, 0, 0);
	373	ds1620_out(THERM_WRITE_CONFIG, 8, CFG_CPU);
	374	ds1620_out(THERM_START_CONVERT, 0, 0);
	375
	376	/*
	377	* Trigger the fan to start by setting
	378	* temperature high point low. This kicks
	379	* the fan into action.
	380	*/
	381	ds1620_read_state(&th);
	382	th_start.lo = 0;
	383	th_start.hi = 1;
	384	ds1620_write_state(&th_start);
	385
	386	msleep(2000);
	387
	388	ds1620_write_state(&th);
	389
	390	ret = misc_register(&ds1620_miscdev);
	391	if (ret < 0)
	392	return ret;
	393
	394	#ifdef THERM_USE_PROC
3f3942ac	395	if (!proc_create_single("therm", 0, NULL, ds1620_proc_therm_show))
1da177e4 LT	396	printk(KERN_ERR "therm: unable to register /proc/therm\n");
	397	#endif
	398
	399	ds1620_read_state(&th);
	400	ret = cvt_9_to_int(ds1620_in(THERM_READ_TEMP, 9));
	401
	402	printk(KERN_INFO "Thermostat: high %i.%i, low %i.%i, "
	403	"current %i.%i C, fan %s.\n",
	404	th.hi >> 1, th.hi & 1 ? 5 : 0,
	405	th.lo >> 1, th.lo & 1 ? 5 : 0,
	406	ret >> 1, ret & 1 ? 5 : 0,
	407	fan_state[netwinder_get_fan()]);
	408
	409	return 0;
	410	}
	411
	412	static void __exit ds1620_exit(void)
	413	{
	414	#ifdef THERM_USE_PROC
	415	remove_proc_entry("therm", NULL);
	416	#endif
	417	misc_deregister(&ds1620_miscdev);
	418	}
	419
	420	module_init(ds1620_init);
	421	module_exit(ds1620_exit);
	422
	423	MODULE_LICENSE("GPL");