+/*
+ * set general purpose IO pin state and direction
+ *
+ * user_gpio fields:
+ * state each bit indicates a pin state
+ * smask set bit indicates pin state to set
+ * dir each bit indicates a pin direction (0=input, 1=output)
+ * dmask set bit indicates pin direction to set
+ */
+static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
+{
+ unsigned long flags;
+ struct gpio_desc gpio;
+ __u32 data;
+
+ if (!info->gpio_present)
+ return -EINVAL;
+ if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
+ return -EFAULT;
+ DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
+ info->device_name, gpio.state, gpio.smask,
+ gpio.dir, gpio.dmask));
+
+ spin_lock_irqsave(&info->lock,flags);
+ if (gpio.dmask) {
+ data = rd_reg32(info, IODR);
+ data |= gpio.dmask & gpio.dir;
+ data &= ~(gpio.dmask & ~gpio.dir);
+ wr_reg32(info, IODR, data);
+ }
+ if (gpio.smask) {
+ data = rd_reg32(info, IOVR);
+ data |= gpio.smask & gpio.state;
+ data &= ~(gpio.smask & ~gpio.state);
+ wr_reg32(info, IOVR, data);
+ }
+ spin_unlock_irqrestore(&info->lock,flags);
+
+ return 0;
+}
+
+/*
+ * get general purpose IO pin state and direction
+ */
+static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
+{
+ struct gpio_desc gpio;
+ if (!info->gpio_present)
+ return -EINVAL;
+ gpio.state = rd_reg32(info, IOVR);
+ gpio.smask = 0xffffffff;
+ gpio.dir = rd_reg32(info, IODR);
+ gpio.dmask = 0xffffffff;
+ if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
+ return -EFAULT;
+ DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
+ info->device_name, gpio.state, gpio.dir));
+ return 0;
+}
+
+/*
+ * conditional wait facility
+ */
+static void init_cond_wait(struct cond_wait *w, unsigned int data)
+{
+ init_waitqueue_head(&w->q);
+ init_waitqueue_entry(&w->wait, current);
+ w->data = data;
+}
+
+static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
+{
+ set_current_state(TASK_INTERRUPTIBLE);
+ add_wait_queue(&w->q, &w->wait);
+ w->next = *head;
+ *head = w;
+}
+
+static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
+{
+ struct cond_wait *w, *prev;
+ remove_wait_queue(&cw->q, &cw->wait);
+ set_current_state(TASK_RUNNING);
+ for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
+ if (w == cw) {
+ if (prev != NULL)
+ prev->next = w->next;
+ else
+ *head = w->next;
+ break;
+ }
+ }
+}
+
+static void flush_cond_wait(struct cond_wait **head)
+{
+ while (*head != NULL) {
+ wake_up_interruptible(&(*head)->q);
+ *head = (*head)->next;
+ }
+}
+
+/*
+ * wait for general purpose I/O pin(s) to enter specified state
+ *
+ * user_gpio fields:
+ * state - bit indicates target pin state
+ * smask - set bit indicates watched pin
+ *
+ * The wait ends when at least one watched pin enters the specified
+ * state. When 0 (no error) is returned, user_gpio->state is set to the
+ * state of all GPIO pins when the wait ends.
+ *
+ * Note: Each pin may be a dedicated input, dedicated output, or
+ * configurable input/output. The number and configuration of pins
+ * varies with the specific adapter model. Only input pins (dedicated
+ * or configured) can be monitored with this function.
+ */
+static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
+{
+ unsigned long flags;
+ int rc = 0;
+ struct gpio_desc gpio;
+ struct cond_wait wait;
+ u32 state;
+
+ if (!info->gpio_present)
+ return -EINVAL;
+ if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
+ return -EFAULT;
+ DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
+ info->device_name, gpio.state, gpio.smask));
+ /* ignore output pins identified by set IODR bit */
+ if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
+ return -EINVAL;
+ init_cond_wait(&wait, gpio.smask);
+
+ spin_lock_irqsave(&info->lock, flags);
+ /* enable interrupts for watched pins */
+ wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
+ /* get current pin states */
+ state = rd_reg32(info, IOVR);
+
+ if (gpio.smask & ~(state ^ gpio.state)) {
+ /* already in target state */
+ gpio.state = state;
+ } else {
+ /* wait for target state */
+ add_cond_wait(&info->gpio_wait_q, &wait);
+ spin_unlock_irqrestore(&info->lock, flags);
+ schedule();
+ if (signal_pending(current))
+ rc = -ERESTARTSYS;
+ else
+ gpio.state = wait.data;
+ spin_lock_irqsave(&info->lock, flags);
+ remove_cond_wait(&info->gpio_wait_q, &wait);
+ }
+
+ /* disable all GPIO interrupts if no waiting processes */
+ if (info->gpio_wait_q == NULL)
+ wr_reg32(info, IOER, 0);
+ spin_unlock_irqrestore(&info->lock,flags);
+
+ if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
+ rc = -EFAULT;
+ return rc;
+}
+