| /* |
| * linux/kernel/chr_drv/psaux.c |
| * |
| * Driver for PS/2 type mouse by Johan Myreen. |
| * |
| * Supports pointing devices attached to a PS/2 type |
| * Keyboard and Auxiliary Device Controller. |
| * |
| * Modified by Dean Troyer (troyer@saifr00.cfsat.Honeywell.COM) 03Oct92 |
| * to perform (some of) the hardware initialization formerly done in |
| * setup.S by the BIOS |
| * |
| * Modified by Dean Troyer (troyer@saifr00.cfsat.Honeywell.COM) 09Oct92 |
| * to perform the hardware initialization formerly done in setup.S by |
| * the BIOS. Mouse characteristic setup is now included. |
| * |
| */ |
| |
| #include <linux/timer.h> |
| #include <linux/sched.h> |
| #include <linux/kernel.h> |
| #include <linux/fcntl.h> |
| #include <linux/errno.h> |
| |
| #include <asm/io.h> |
| #include <asm/segment.h> |
| #include <asm/system.h> |
| |
| /* aux controller ports */ |
| #define AUX_INPUT_PORT 0x60 /* Aux device output buffer */ |
| #define AUX_OUTPUT_PORT 0x60 /* Aux device input buffer */ |
| #define AUX_COMMAND 0x64 /* Aux device command buffer */ |
| #define AUX_STATUS 0x64 /* Aux device status reg */ |
| |
| /* aux controller status bits */ |
| #define AUX_OBUF_FULL 0x01 /* output buffer (from device) full */ |
| #define AUX_IBUF_FULL 0x02 /* input buffer (to device) full */ |
| |
| /* aux controller commands */ |
| #define AUX_CMD_WRITE 0x60 /* value to write to controller */ |
| #define AUX_MAGIC_WRITE 0xd4 /* value to send aux device data */ |
| |
| #define AUX_INTS_ON 0x47 /* enable controller interrupts */ |
| #define AUX_INTS_OFF 0x65 /* disable controller interrupts */ |
| |
| #define AUX_DISABLE 0xa7 /* disable aux */ |
| #define AUX_ENABLE 0xa8 /* enable aux */ |
| |
| /* aux device commands */ |
| #define AUX_SET_RES 0xe8 /* set resolution */ |
| #define AUX_SET_SCALE 0xe9 /* set scaling factor */ |
| #define AUX_SET_STREAM 0xea /* set stream mode */ |
| #define AUX_SET_SAMPLE 0xf3 /* set sample rate */ |
| #define AUX_ENABLE_DEV 0xf4 /* enable aux device */ |
| #define AUX_DISABLE_DEV 0xf5 /* disable aux device */ |
| #define AUX_RESET 0xff /* reset aux device */ |
| |
| #define MAX_RETRIES 3 |
| #define AUX_IRQ 12 |
| #define AUX_BUF_SIZE 2048 |
| |
| extern unsigned char aux_device_present; |
| |
| struct aux_queue { |
| unsigned long head; |
| unsigned long tail; |
| struct wait_queue *proc_list; |
| unsigned char buf[AUX_BUF_SIZE]; |
| }; |
| |
| static struct aux_queue *queue; |
| static int aux_ready = 0; |
| static int aux_busy = 0; |
| static int aux_present = 0; |
| |
| static int poll_status(void); |
| |
| /* |
| * Write to aux device |
| */ |
| static void aux_write_dev(int val) |
| { |
| poll_status(); |
| outb_p(AUX_MAGIC_WRITE,AUX_COMMAND); /* write magic cookie */ |
| poll_status(); |
| outb_p(val,AUX_OUTPUT_PORT); /* write data */ |
| |
| } |
| |
| #if 0 |
| /* |
| * Write to device & handle returned ack |
| */ |
| |
| static int aux_write_ack(int val) |
| { |
| aux_write_dev(val); /* write the value to the device */ |
| while ((inb(AUX_STATUS) & AUX_OBUF_FULL) == 0); /* wait for ack */ |
| if ((inb(AUX_STATUS) & 0x20) == 0x20) |
| { |
| return (inb(AUX_INPUT_PORT)); |
| } |
| return 0; |
| } |
| #endif |
| |
| /* |
| * Write aux device command |
| */ |
| |
| static void aux_write_cmd(int val) |
| { |
| poll_status(); |
| outb_p(AUX_CMD_WRITE,AUX_COMMAND); |
| poll_status(); |
| outb_p(val,AUX_OUTPUT_PORT); |
| } |
| |
| |
| static unsigned int get_from_queue(void) |
| { |
| unsigned int result; |
| unsigned long flags; |
| |
| save_flags(flags); |
| cli(); |
| result = queue->buf[queue->tail]; |
| queue->tail = (queue->tail + 1) & (AUX_BUF_SIZE-1); |
| restore_flags(flags); |
| return result; |
| } |
| |
| |
| static inline int queue_empty(void) |
| { |
| return queue->head == queue->tail; |
| } |
| |
| |
| /* |
| * Interrupt from the auxiliary device: a character |
| * is waiting in the keyboard/aux controller. |
| */ |
| |
| static void aux_interrupt(int cpl) |
| { |
| int head = queue->head; |
| int maxhead = (queue->tail-1) & (AUX_BUF_SIZE-1); |
| |
| queue->buf[head] = inb(AUX_INPUT_PORT); |
| if (head != maxhead) { |
| head++; |
| head &= AUX_BUF_SIZE-1; |
| } |
| queue->head = head; |
| aux_ready = 1; |
| wake_up_interruptible(&queue->proc_list); |
| } |
| |
| |
| static void release_aux(struct inode * inode, struct file * file) |
| { |
| poll_status(); |
| aux_write_dev(AUX_DISABLE_DEV); /* disable aux device */ |
| poll_status(); |
| outb_p(AUX_DISABLE,AUX_COMMAND); /* Disable Aux device */ |
| aux_write_cmd(AUX_INTS_OFF); /* disable controller ints */ |
| free_irq(AUX_IRQ); |
| aux_busy = 0; |
| } |
| |
| |
| /* |
| * Install interrupt handler. |
| * Enable auxiliary device. |
| */ |
| |
| static int open_aux(struct inode * inode, struct file * file) |
| { |
| if (!aux_present) |
| return -EINVAL; |
| if (aux_busy) |
| return -EBUSY; |
| if (!poll_status()) |
| return -EBUSY; |
| aux_busy = 1; |
| queue->head = queue->tail = 0; /* Flush input queue */ |
| if (request_irq(AUX_IRQ, aux_interrupt)) |
| return -EBUSY; |
| aux_write_dev(AUX_ENABLE_DEV); /* enable aux device */ |
| aux_write_cmd(AUX_INTS_ON); /* enable controller ints */ |
| poll_status(); |
| outb_p(AUX_ENABLE,AUX_COMMAND); /* Enable Aux */ |
| return 0; |
| } |
| |
| |
| /* |
| * Write to the aux device. |
| */ |
| |
| static int write_aux(struct inode * inode, struct file * file, char * buffer, int count) |
| { |
| int i = count; |
| |
| while (i--) { |
| if (!poll_status()) |
| return -EIO; |
| outb_p(AUX_MAGIC_WRITE,AUX_COMMAND); |
| if (!poll_status()) |
| return -EIO; |
| outb_p(get_fs_byte(buffer++),AUX_OUTPUT_PORT); |
| } |
| inode->i_mtime = CURRENT_TIME; |
| return count; |
| } |
| |
| |
| /* |
| * Put bytes from input queue to buffer. |
| */ |
| |
| static int read_aux(struct inode * inode, struct file * file, char * buffer, int count) |
| { |
| struct wait_queue wait = { current, NULL }; |
| int i = count; |
| unsigned char c; |
| |
| if (queue_empty()) { |
| if (file->f_flags & O_NONBLOCK) |
| return -EAGAIN; |
| add_wait_queue(&queue->proc_list, &wait); |
| repeat: |
| current->state = TASK_INTERRUPTIBLE; |
| if (queue_empty() && !(current->signal & ~current->blocked)) { |
| schedule(); |
| goto repeat; |
| } |
| current->state = TASK_RUNNING; |
| remove_wait_queue(&queue->proc_list, &wait); |
| } |
| while (i > 0 && !queue_empty()) { |
| c = get_from_queue(); |
| put_fs_byte(c, buffer++); |
| i--; |
| } |
| aux_ready = !queue_empty(); |
| if (count-i) { |
| inode->i_atime = CURRENT_TIME; |
| return count-i; |
| } |
| if (current->signal & ~current->blocked) |
| return -ERESTARTSYS; |
| return 0; |
| } |
| |
| |
| static int aux_select(struct inode *inode, struct file *file, int sel_type, select_table * wait) |
| { |
| if (sel_type != SEL_IN) |
| return 0; |
| if (aux_ready) |
| return 1; |
| select_wait(&queue->proc_list, wait); |
| return 0; |
| } |
| |
| |
| struct file_operations psaux_fops = { |
| NULL, /* seek */ |
| read_aux, |
| write_aux, |
| NULL, /* readdir */ |
| aux_select, |
| NULL, /* ioctl */ |
| NULL, /* mmap */ |
| open_aux, |
| release_aux, |
| }; |
| |
| |
| unsigned long psaux_init(unsigned long kmem_start) |
| { |
| if (aux_device_present != 0xaa) { |
| return kmem_start; |
| } |
| printk("PS/2 type pointing device detected and installed.\n"); |
| queue = (struct aux_queue *) kmem_start; |
| kmem_start += sizeof (struct aux_queue); |
| queue->head = queue->tail = 0; |
| queue->proc_list = NULL; |
| aux_present = 1; |
| poll_status(); |
| outb_p(AUX_DISABLE,AUX_COMMAND); /* Disable Aux device */ |
| aux_write_cmd(AUX_INTS_OFF); /* disable controller ints */ |
| return kmem_start; |
| } |
| |
| |
| static int poll_status(void) |
| { |
| int retries=0; |
| |
| while ((inb(AUX_STATUS)&0x03) && retries++ < MAX_RETRIES) { |
| if (inb_p(AUX_STATUS)&0x01) |
| inb_p(AUX_INPUT_PORT); |
| current->state = TASK_INTERRUPTIBLE; |
| current->timeout = jiffies + 5; |
| schedule(); |
| } |
| return !(retries==MAX_RETRIES); |
| } |