| /* |
| * 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/capability.h> |
| #include <linux/init.h> |
| #include <linux/smp_lock.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 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) |
| { |
| spin_lock_irqsave(&nw_gpio_lock, *flags); |
| } |
| |
| static inline void netwinder_unlock(unsigned long *flags) |
| { |
| spin_unlock_irqrestore(&nw_gpio_lock, *flags); |
| } |
| |
| static inline void netwinder_set_fan(int i) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&nw_gpio_lock, flags); |
| nw_gpio_modify_op(GPIO_FAN, i ? GPIO_FAN : 0); |
| 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) |
| { |
| cycle_kernel_lock(); |
| 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; |
| |
| lock_kernel(); |
| ret = ds1620_ioctl(file, cmd, arg); |
| unlock_kernel(); |
| |
| return ret; |
| } |
| |
| #ifdef THERM_USE_PROC |
| static int |
| proc_therm_ds1620_read(char *buf, char **start, off_t offset, |
| int len, int *eof, void *unused) |
| { |
| struct therm th; |
| int temp; |
| |
| ds1620_read_state(&th); |
| temp = cvt_9_to_int(ds1620_in(THERM_READ_TEMP, 9)); |
| |
| len = sprintf(buf, "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 len; |
| } |
| |
| static struct proc_dir_entry *proc_therm_ds1620; |
| #endif |
| |
| static const struct file_operations ds1620_fops = { |
| .owner = THIS_MODULE, |
| .open = ds1620_open, |
| .read = ds1620_read, |
| .unlocked_ioctl = ds1620_unlocked_ioctl, |
| }; |
| |
| 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 |
| proc_therm_ds1620 = create_proc_entry("therm", 0, NULL); |
| if (proc_therm_ds1620) |
| proc_therm_ds1620->read_proc = proc_therm_ds1620_read; |
| else |
| 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"); |