Misc: phantom, improved data passing

This new version guarantees amb_bit switch in small enough intervals, so that
the device won't stop working in the middle of a movement anymore.  However it
preserves old (openhaptics) functionality.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/misc/phantom.c b/drivers/misc/phantom.c
index bc532ac..cd221fd 100644 (file)
--- a/drivers/misc/phantom.c
+++ b/drivers/misc/phantom.c
@@ -25,13 +25,14 @@
 #include <asm/atomic.h>
 #include <asm/io.h>
 
-#define PHANTOM_VERSION                "n0.9.5"
+#define PHANTOM_VERSION                "n0.9.7"
 
 #define PHANTOM_MAX_MINORS     8
 
 #define PHN_IRQCTL             0x4c    /* irq control in caddr space */
 
 #define PHB_RUNNING            1
+#define PHB_NOT_OH             2
 
 static struct class *phantom_class;
 static int phantom_major;
@@ -48,7 +49,11 @@ struct phantom_device {
        struct cdev cdev;
 
        struct mutex open_lock;
-       spinlock_t ioctl_lock;
+       spinlock_t regs_lock;
+
+       /* used in NOT_OH mode */
+       struct phm_regs oregs;
+       u32 ctl_reg;
 };
 
 static unsigned char phantom_devices[PHANTOM_MAX_MINORS];
@@ -83,6 +88,7 @@ static long phantom_ioctl(struct file *file, unsigned int cmd,
        struct phm_regs rs;
        struct phm_reg r;
        void __user *argp = (void __user *)arg;
+       unsigned long flags;
        unsigned int i;
 
        if (_IOC_TYPE(cmd) != PH_IOC_MAGIC ||
@@ -97,32 +103,45 @@ static long phantom_ioctl(struct file *file, unsigned int cmd,
                if (r.reg > 7)
                        return -EINVAL;
 
-               spin_lock(&dev->ioctl_lock);
+               spin_lock_irqsave(&dev->regs_lock, flags);
                if (r.reg == PHN_CONTROL && (r.value & PHN_CTL_IRQ) &&
                                phantom_status(dev, dev->status | PHB_RUNNING)){
-                       spin_unlock(&dev->ioctl_lock);
+                       spin_unlock_irqrestore(&dev->regs_lock, flags);
                        return -ENODEV;
                }
 
                pr_debug("phantom: writing %x to %u\n", r.value, r.reg);
+
+               /* preserve amp bit (don't allow to change it when in NOT_OH) */
+               if (r.reg == PHN_CONTROL && (dev->status & PHB_NOT_OH)) {
+                       r.value &= ~PHN_CTL_AMP;
+                       r.value |= dev->ctl_reg & PHN_CTL_AMP;
+                       dev->ctl_reg = r.value;
+               }
+
                iowrite32(r.value, dev->iaddr + r.reg);
                ioread32(dev->iaddr); /* PCI posting */
 
                if (r.reg == PHN_CONTROL && !(r.value & PHN_CTL_IRQ))
                        phantom_status(dev, dev->status & ~PHB_RUNNING);
-               spin_unlock(&dev->ioctl_lock);
+               spin_unlock_irqrestore(&dev->regs_lock, flags);
                break;
        case PHN_SET_REGS:
                if (copy_from_user(&rs, argp, sizeof(rs)))
                        return -EFAULT;
 
                pr_debug("phantom: SRS %u regs %x\n", rs.count, rs.mask);
-               spin_lock(&dev->ioctl_lock);
-               for (i = 0; i < min(rs.count, 8U); i++)
-                       if ((1 << i) & rs.mask)
-                               iowrite32(rs.values[i], dev->oaddr + i);
-               ioread32(dev->iaddr); /* PCI posting */
-               spin_unlock(&dev->ioctl_lock);
+               spin_lock_irqsave(&dev->regs_lock, flags);
+               if (dev->status & PHB_NOT_OH)
+                       memcpy(&dev->oregs, &rs, sizeof(rs));
+               else {
+                       u32 m = min(rs.count, 8U);
+                       for (i = 0; i < m; i++)
+                               if (rs.mask & BIT(i))
+                                       iowrite32(rs.values[i], dev->oaddr + i);
+                       ioread32(dev->iaddr); /* PCI posting */
+               }
+               spin_unlock_irqrestore(&dev->regs_lock, flags);
                break;
        case PHN_GET_REG:
                if (copy_from_user(&r, argp, sizeof(r)))
@@ -136,20 +155,35 @@ static long phantom_ioctl(struct file *file, unsigned int cmd,
                if (copy_to_user(argp, &r, sizeof(r)))
                        return -EFAULT;
                break;
-       case PHN_GET_REGS:
+       case PHN_GET_REGS: {
+               u32 m;
+
                if (copy_from_user(&rs, argp, sizeof(rs)))
                        return -EFAULT;
 
+               m = min(rs.count, 8U);
+
                pr_debug("phantom: GRS %u regs %x\n", rs.count, rs.mask);
-               spin_lock(&dev->ioctl_lock);
-               for (i = 0; i < min(rs.count, 8U); i++)
-                       if ((1 << i) & rs.mask)
+               spin_lock_irqsave(&dev->regs_lock, flags);
+               for (i = 0; i < m; i++)
+                       if (rs.mask & BIT(i))
                                rs.values[i] = ioread32(dev->iaddr + i);
-               spin_unlock(&dev->ioctl_lock);
+               spin_unlock_irqrestore(&dev->regs_lock, flags);
 
                if (copy_to_user(argp, &rs, sizeof(rs)))
                        return -EFAULT;
                break;
+       } case PHN_NOT_OH:
+               spin_lock_irqsave(&dev->regs_lock, flags);
+               if (dev->status & PHB_RUNNING) {
+                       printk(KERN_ERR "phantom: you need to set NOT_OH "
+                                       "before you start the device!\n");
+                       spin_unlock_irqrestore(&dev->regs_lock, flags);
+                       return -EINVAL;
+               }
+               dev->status |= PHB_NOT_OH;
+               spin_unlock_irqrestore(&dev->regs_lock, flags);
+               break;
        default:
                return -ENOTTY;
        }
@@ -172,8 +206,11 @@ static int phantom_open(struct inode *inode, struct file *file)
                return -EINVAL;
        }
 
+       WARN_ON(dev->status & PHB_NOT_OH);
+
        file->private_data = dev;
 
+       atomic_set(&dev->counter, 0);
        dev->opened++;
        mutex_unlock(&dev->open_lock);
 
@@ -188,6 +225,7 @@ static int phantom_release(struct inode *inode, struct file *file)
 
        dev->opened = 0;
        phantom_status(dev, dev->status & ~PHB_RUNNING);
+       dev->status &= ~PHB_NOT_OH;
 
        mutex_unlock(&dev->open_lock);
 
@@ -221,12 +259,32 @@ static struct file_operations phantom_file_ops = {
 static irqreturn_t phantom_isr(int irq, void *data)
 {
        struct phantom_device *dev = data;
+       unsigned int i;
+       u32 ctl;
 
-       if (!(ioread32(dev->iaddr + PHN_CONTROL) & PHN_CTL_IRQ))
+       spin_lock(&dev->regs_lock);
+       ctl = ioread32(dev->iaddr + PHN_CONTROL);
+       if (!(ctl & PHN_CTL_IRQ)) {
+               spin_unlock(&dev->regs_lock);
                return IRQ_NONE;
+       }
 
        iowrite32(0, dev->iaddr);
        iowrite32(0xc0, dev->iaddr);
+
+       if (dev->status & PHB_NOT_OH) {
+               struct phm_regs *r = &dev->oregs;
+               u32 m = min(r->count, 8U);
+
+               for (i = 0; i < m; i++)
+                       if (r->mask & BIT(i))
+                               iowrite32(r->values[i], dev->oaddr + i);
+
+               dev->ctl_reg ^= PHN_CTL_AMP;
+               iowrite32(dev->ctl_reg, dev->iaddr + PHN_CONTROL);
+       }
+       spin_unlock(&dev->regs_lock);
+
        ioread32(dev->iaddr); /* PCI posting */
 
        atomic_inc(&dev->counter);
@@ -298,7 +356,7 @@ static int __devinit phantom_probe(struct pci_dev *pdev,
        }
 
        mutex_init(&pht->open_lock);
-       spin_lock_init(&pht->ioctl_lock);
+       spin_lock_init(&pht->regs_lock);
        init_waitqueue_head(&pht->wait);
        cdev_init(&pht->cdev, &phantom_file_ops);
        pht->cdev.owner = THIS_MODULE;

diff --git a/include/linux/phantom.h b/include/linux/phantom.h
index d3ebbfa..96f4048 100644 (file)
--- a/include/linux/phantom.h
+++ b/include/linux/phantom.h
@@ -30,7 +30,11 @@ struct phm_regs {
 #define PHN_SET_REG            _IOW (PH_IOC_MAGIC, 1, struct phm_reg *)
 #define PHN_GET_REGS           _IOWR(PH_IOC_MAGIC, 2, struct phm_regs *)
 #define PHN_SET_REGS           _IOW (PH_IOC_MAGIC, 3, struct phm_regs *)
-#define PH_IOC_MAXNR           3
+/* this ioctl tells the driver, that the caller is not OpenHaptics and might
+ * use improved registers update (no more phantom switchoffs when using
+ * libphantom) */
+#define PHN_NOT_OH             _IO  (PH_IOC_MAGIC, 4)
+#define PH_IOC_MAXNR           4
 
 #define PHN_CONTROL            0x6     /* control byte in iaddr space */
 #define PHN_CTL_AMP            0x1     /*   switch after torques change */