[POWERPC] PS3: Vuart cleanups

Cleanups for the PS3 vuart driver.

- Hide driver private data from external interface with new structure
  ps3_vuart_port_priv.
- Fix masking bug in ps3_vuart_get_interrupt_status().
- Add new helper routine ps3_vuart_clear_rx_bytes() to flush rx buffer.
- Add new variable probe_mutex to serialize probe and destroy routines.
- Rename some symbols.
- Add platform check in ps3_vuart_bus_init().

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

2 files changed, 245 insertions, 132 deletions

diff --git a/drivers/ps3/vuart.c b/drivers/ps3/vuart.c
index ef8fd4c30875..90b3d1ca5172 100644
--- a/drivers/ps3/vuart.c
+++ b/drivers/ps3/vuart.c
@@ -23,6 +23,7 @@
 #include <linux/interrupt.h>
 #include <asm/ps3.h>
 
+#include <asm/firmware.h>
 #include <asm/lv1call.h>
 #include <asm/bitops.h>
 
@@ -30,7 +31,7 @@
 
 MODULE_AUTHOR("Sony Corporation");
 MODULE_LICENSE("GPL v2");
-MODULE_DESCRIPTION("ps3 vuart");
+MODULE_DESCRIPTION("PS3 vuart");
 
 /**
  * vuart - An inter-partition data link service.
@@ -157,7 +158,7 @@ int ps3_vuart_get_triggers(struct ps3_vuart_port_device *dev,
         unsigned long size;
         unsigned long val;
 
-        result = lv1_get_virtual_uart_param(dev->port_number,
+        result = lv1_get_virtual_uart_param(dev->priv->port_number,
                 PARAM_TX_TRIGGER, &trig->tx);
 
         if (result) {
@@ -166,7 +167,7 @@ int ps3_vuart_get_triggers(struct ps3_vuart_port_device *dev,
                 return result;
         }
 
-        result = lv1_get_virtual_uart_param(dev->port_number,
+        result = lv1_get_virtual_uart_param(dev->priv->port_number,
                 PARAM_RX_BUF_SIZE, &size);
 
         if (result) {
@@ -175,7 +176,7 @@ int ps3_vuart_get_triggers(struct ps3_vuart_port_device *dev,
                 return result;
         }
 
-        result = lv1_get_virtual_uart_param(dev->port_number,
+        result = lv1_get_virtual_uart_param(dev->priv->port_number,
                 PARAM_RX_TRIGGER, &val);
 
         if (result) {
@@ -198,7 +199,7 @@ int ps3_vuart_set_triggers(struct ps3_vuart_port_device *dev, unsigned int tx,
         int result;
         unsigned long size;
 
-        result = lv1_set_virtual_uart_param(dev->port_number,
+        result = lv1_set_virtual_uart_param(dev->priv->port_number,
                 PARAM_TX_TRIGGER, tx);
 
         if (result) {
@@ -207,7 +208,7 @@ int ps3_vuart_set_triggers(struct ps3_vuart_port_device *dev, unsigned int tx,
                 return result;
         }
 
-        result = lv1_get_virtual_uart_param(dev->port_number,
+        result = lv1_get_virtual_uart_param(dev->priv->port_number,
                 PARAM_RX_BUF_SIZE, &size);
 
         if (result) {
@@ -216,7 +217,7 @@ int ps3_vuart_set_triggers(struct ps3_vuart_port_device *dev, unsigned int tx,
                 return result;
         }
 
-        result = lv1_set_virtual_uart_param(dev->port_number,
+        result = lv1_set_virtual_uart_param(dev->priv->port_number,
                 PARAM_RX_TRIGGER, size - rx);
 
         if (result) {
@@ -232,9 +233,9 @@ int ps3_vuart_set_triggers(struct ps3_vuart_port_device *dev, unsigned int tx,
 }
 
 static int ps3_vuart_get_rx_bytes_waiting(struct ps3_vuart_port_device *dev,
-        unsigned long *bytes_waiting)
+        u64 *bytes_waiting)
 {
-        int result = lv1_get_virtual_uart_param(dev->port_number,
+        int result = lv1_get_virtual_uart_param(dev->priv->port_number,
                 PARAM_RX_BYTES, bytes_waiting);
 
         if (result)
@@ -253,10 +254,10 @@ static int ps3_vuart_set_interrupt_mask(struct ps3_vuart_port_device *dev,
 
         dev_dbg(&dev->core, "%s:%d: %lxh\n", __func__, __LINE__, mask);
 
-        dev->interrupt_mask = mask;
+        dev->priv->interrupt_mask = mask;
 
-        result = lv1_set_virtual_uart_param(dev->port_number,
-                PARAM_INTERRUPT_MASK, dev->interrupt_mask);
+        result = lv1_set_virtual_uart_param(dev->priv->port_number,
+                PARAM_INTERRUPT_MASK, dev->priv->interrupt_mask);
 
         if (result)
                 dev_dbg(&dev->core, "%s:%d: interrupt_mask failed: %s\n",
@@ -265,62 +266,64 @@ static int ps3_vuart_set_interrupt_mask(struct ps3_vuart_port_device *dev,
         return result;
 }
 
-static int ps3_vuart_get_interrupt_mask(struct ps3_vuart_port_device *dev,
+static int ps3_vuart_get_interrupt_status(struct ps3_vuart_port_device *dev,
         unsigned long *status)
 {
-        int result = lv1_get_virtual_uart_param(dev->port_number,
-                PARAM_INTERRUPT_STATUS, status);
+        u64 tmp;
+        int result = lv1_get_virtual_uart_param(dev->priv->port_number,
+                PARAM_INTERRUPT_STATUS, &tmp);
 
         if (result)
                 dev_dbg(&dev->core, "%s:%d: interrupt_status failed: %s\n",
                         __func__, __LINE__, ps3_result(result));
 
+        *status = tmp & dev->priv->interrupt_mask;
+
         dev_dbg(&dev->core, "%s:%d: m %lxh, s %lxh, m&s %lxh\n",
-                __func__, __LINE__, dev->interrupt_mask, *status,
-                dev->interrupt_mask & *status);
+                __func__, __LINE__, dev->priv->interrupt_mask, tmp, *status);
 
         return result;
 }
 
 int ps3_vuart_enable_interrupt_tx(struct ps3_vuart_port_device *dev)
 {
-        return (dev->interrupt_mask & INTERRUPT_MASK_TX) ? 0
-                : ps3_vuart_set_interrupt_mask(dev, dev->interrupt_mask
+        return (dev->priv->interrupt_mask & INTERRUPT_MASK_TX) ? 0
+                : ps3_vuart_set_interrupt_mask(dev, dev->priv->interrupt_mask
                 | INTERRUPT_MASK_TX);
 }
 
 int ps3_vuart_enable_interrupt_rx(struct ps3_vuart_port_device *dev)
 {
-        return (dev->interrupt_mask & INTERRUPT_MASK_RX) ? 0
-                : ps3_vuart_set_interrupt_mask(dev, dev->interrupt_mask
+        return (dev->priv->interrupt_mask & INTERRUPT_MASK_RX) ? 0
+                : ps3_vuart_set_interrupt_mask(dev, dev->priv->interrupt_mask
                 | INTERRUPT_MASK_RX);
 }
 
 int ps3_vuart_enable_interrupt_disconnect(struct ps3_vuart_port_device *dev)
 {
-        return (dev->interrupt_mask & INTERRUPT_MASK_DISCONNECT) ? 0
-                : ps3_vuart_set_interrupt_mask(dev, dev->interrupt_mask
+        return (dev->priv->interrupt_mask & INTERRUPT_MASK_DISCONNECT) ? 0
+                : ps3_vuart_set_interrupt_mask(dev, dev->priv->interrupt_mask
                 | INTERRUPT_MASK_DISCONNECT);
 }
 
 int ps3_vuart_disable_interrupt_tx(struct ps3_vuart_port_device *dev)
 {
-        return (dev->interrupt_mask & INTERRUPT_MASK_TX)
-                ? ps3_vuart_set_interrupt_mask(dev, dev->interrupt_mask
+        return (dev->priv->interrupt_mask & INTERRUPT_MASK_TX)
+                ? ps3_vuart_set_interrupt_mask(dev, dev->priv->interrupt_mask
                 & ~INTERRUPT_MASK_TX) : 0;
 }
 
 int ps3_vuart_disable_interrupt_rx(struct ps3_vuart_port_device *dev)
 {
-        return (dev->interrupt_mask & INTERRUPT_MASK_RX)
-                ? ps3_vuart_set_interrupt_mask(dev, dev->interrupt_mask
+        return (dev->priv->interrupt_mask & INTERRUPT_MASK_RX)
+                ? ps3_vuart_set_interrupt_mask(dev, dev->priv->interrupt_mask
                 & ~INTERRUPT_MASK_RX) : 0;
 }
 
 int ps3_vuart_disable_interrupt_disconnect(struct ps3_vuart_port_device *dev)
 {
-        return (dev->interrupt_mask & INTERRUPT_MASK_DISCONNECT)
-                ? ps3_vuart_set_interrupt_mask(dev, dev->interrupt_mask
+        return (dev->priv->interrupt_mask & INTERRUPT_MASK_DISCONNECT)
+                ? ps3_vuart_set_interrupt_mask(dev, dev->priv->interrupt_mask
                 & ~INTERRUPT_MASK_DISCONNECT) : 0;
 }
 
@@ -335,9 +338,7 @@ static int ps3_vuart_raw_write(struct ps3_vuart_port_device *dev,
 {
         int result;
 
-        dev_dbg(&dev->core, "%s:%d: %xh\n", __func__, __LINE__, bytes);
-
-        result = lv1_write_virtual_uart(dev->port_number,
+        result = lv1_write_virtual_uart(dev->priv->port_number,
                 ps3_mm_phys_to_lpar(__pa(buf)), bytes, bytes_written);
 
         if (result) {
@@ -346,10 +347,10 @@ static int ps3_vuart_raw_write(struct ps3_vuart_port_device *dev,
                 return result;
         }
 
-        dev->stats.bytes_written += *bytes_written;
+        dev->priv->stats.bytes_written += *bytes_written;
 
-        dev_dbg(&dev->core, "%s:%d: wrote %lxh/%xh=>%lxh\n", __func__,
-                __LINE__, *bytes_written, bytes, dev->stats.bytes_written);
+        dev_dbg(&dev->core, "%s:%d: wrote %lxh/%xh=>%lxh\n", __func__, __LINE__,
+                *bytes_written, bytes, dev->priv->stats.bytes_written);
 
         return result;
 }
@@ -367,7 +368,7 @@ static int ps3_vuart_raw_read(struct ps3_vuart_port_device *dev, void* buf,
 
         dev_dbg(&dev->core, "%s:%d: %xh\n", __func__, __LINE__, bytes);
 
-        result = lv1_read_virtual_uart(dev->port_number,
+        result = lv1_read_virtual_uart(dev->priv->port_number,
                 ps3_mm_phys_to_lpar(__pa(buf)), bytes, bytes_read);
 
         if (result) {
@@ -376,15 +377,58 @@ static int ps3_vuart_raw_read(struct ps3_vuart_port_device *dev, void* buf,
                 return result;
         }
 
-        dev->stats.bytes_read += *bytes_read;
+        dev->priv->stats.bytes_read += *bytes_read;
 
         dev_dbg(&dev->core, "%s:%d: read %lxh/%xh=>%lxh\n", __func__, __LINE__,
-                *bytes_read, bytes, dev->stats.bytes_read);
+                *bytes_read, bytes, dev->priv->stats.bytes_read);
 
         return result;
 }
 
 /**
+ * ps3_vuart_clear_rx_bytes - Discard bytes received.
+ * @bytes: Max byte count to discard, zero = all pending.
+ *
+ * Used to clear pending rx interrupt source.  Will not block.
+ */
+
+void ps3_vuart_clear_rx_bytes(struct ps3_vuart_port_device *dev,
+        unsigned int bytes)
+{
+        int result;
+        u64 bytes_waiting;
+        void* tmp;
+
+        result = ps3_vuart_get_rx_bytes_waiting(dev, &bytes_waiting);
+
+        BUG_ON(result);
+
+        bytes = bytes ? min(bytes, (unsigned int)bytes_waiting) : bytes_waiting;
+
+        dev_dbg(&dev->core, "%s:%d: %u\n", __func__, __LINE__, bytes);
+
+        if (!bytes)
+                return;
+
+        /* Add some extra space for recently arrived data. */
+
+        bytes += 128;
+
+        tmp = kmalloc(bytes, GFP_KERNEL);
+
+        if (!tmp)
+                return;
+
+        ps3_vuart_raw_read(dev, tmp, bytes, &bytes_waiting);
+
+        kfree(tmp);
+
+        /* Don't include these bytes in the stats. */
+
+        dev->priv->stats.bytes_read -= bytes_waiting;
+}
+
+/**
  * struct list_buffer - An element for a port device fifo buffer list.
  */
 
@@ -416,14 +460,14 @@ int ps3_vuart_write(struct ps3_vuart_port_device *dev, const void* buf,
         dev_dbg(&dev->core, "%s:%d: %u(%xh) bytes\n", __func__, __LINE__,
                 bytes, bytes);
 
-        spin_lock_irqsave(&dev->tx_list.lock, flags);
+        spin_lock_irqsave(&dev->priv->tx_list.lock, flags);
 
-        if (list_empty(&dev->tx_list.head)) {
+        if (list_empty(&dev->priv->tx_list.head)) {
                 unsigned long bytes_written;
 
                 result = ps3_vuart_raw_write(dev, buf, bytes, &bytes_written);
 
-                spin_unlock_irqrestore(&dev->tx_list.lock, flags);
+                spin_unlock_irqrestore(&dev->priv->tx_list.lock, flags);
 
                 if (result) {
                         dev_dbg(&dev->core,
@@ -441,7 +485,7 @@ int ps3_vuart_write(struct ps3_vuart_port_device *dev, const void* buf,
                 bytes -= bytes_written;
                 buf += bytes_written;
         } else
-                spin_unlock_irqrestore(&dev->tx_list.lock, flags);
+                spin_unlock_irqrestore(&dev->priv->tx_list.lock, flags);
 
         lb = kmalloc(sizeof(struct list_buffer) + bytes, GFP_KERNEL);
 
@@ -454,10 +498,10 @@ int ps3_vuart_write(struct ps3_vuart_port_device *dev, const void* buf,
         lb->tail = lb->data + bytes;
         lb->dbg_number = ++dbg_number;
 
-        spin_lock_irqsave(&dev->tx_list.lock, flags);
-        list_add_tail(&lb->link, &dev->tx_list.head);
+        spin_lock_irqsave(&dev->priv->tx_list.lock, flags);
+        list_add_tail(&lb->link, &dev->priv->tx_list.head);
         ps3_vuart_enable_interrupt_tx(dev);
-        spin_unlock_irqrestore(&dev->tx_list.lock, flags);
+        spin_unlock_irqrestore(&dev->priv->tx_list.lock, flags);
 
         dev_dbg(&dev->core, "%s:%d: queued buf_%lu, %xh bytes\n",
                 __func__, __LINE__, lb->dbg_number, bytes);
@@ -484,44 +528,42 @@ int ps3_vuart_read(struct ps3_vuart_port_device *dev, void* buf,
         dev_dbg(&dev->core, "%s:%d: %u(%xh) bytes\n", __func__, __LINE__,
                 bytes, bytes);
 
-        spin_lock_irqsave(&dev->rx_list.lock, flags);
+        spin_lock_irqsave(&dev->priv->rx_list.lock, flags);
 
-        if (dev->rx_list.bytes_held < bytes) {
-                spin_unlock_irqrestore(&dev->rx_list.lock, flags);
+        if (dev->priv->rx_list.bytes_held < bytes) {
+                spin_unlock_irqrestore(&dev->priv->rx_list.lock, flags);
                 dev_dbg(&dev->core, "%s:%d: starved for %lxh bytes\n",
-                        __func__, __LINE__, bytes - dev->rx_list.bytes_held);
+                        __func__, __LINE__,
+                        bytes - dev->priv->rx_list.bytes_held);
                 return -EAGAIN;
         }
 
-        list_for_each_entry_safe(lb, n, &dev->rx_list.head, link) {
+        list_for_each_entry_safe(lb, n, &dev->priv->rx_list.head, link) {
                 bytes_read = min((unsigned int)(lb->tail - lb->head), bytes);
 
                 memcpy(buf, lb->head, bytes_read);
                 buf += bytes_read;
                 bytes -= bytes_read;
-                dev->rx_list.bytes_held -= bytes_read;
+                dev->priv->rx_list.bytes_held -= bytes_read;
 
                 if (bytes_read < lb->tail - lb->head) {
                         lb->head += bytes_read;
-                        spin_unlock_irqrestore(&dev->rx_list.lock, flags);
-
-                        dev_dbg(&dev->core,
-                                "%s:%d: dequeued buf_%lu, %lxh bytes\n",
-                                __func__, __LINE__, lb->dbg_number, bytes_read);
+                        dev_dbg(&dev->core, "%s:%d: buf_%lu: dequeued %lxh "
+                                "bytes\n", __func__, __LINE__, lb->dbg_number,
+                                bytes_read);
+                        spin_unlock_irqrestore(&dev->priv->rx_list.lock, flags);
                         return 0;
                 }
 
-                dev_dbg(&dev->core, "%s:%d free buf_%lu\n", __func__, __LINE__,
-                        lb->dbg_number);
+                dev_dbg(&dev->core, "%s:%d: buf_%lu: free, dequeued %lxh "
+                        "bytes\n", __func__, __LINE__, lb->dbg_number,
+                        bytes_read);
 
                 list_del(&lb->link);
                 kfree(lb);
         }
-        spin_unlock_irqrestore(&dev->rx_list.lock, flags);
-
-        dev_dbg(&dev->core, "%s:%d: dequeued buf_%lu, %xh bytes\n",
-                __func__, __LINE__, lb->dbg_number, bytes);
 
+        spin_unlock_irqrestore(&dev->priv->rx_list.lock, flags);
         return 0;
 }
 
@@ -542,9 +584,9 @@ static int ps3_vuart_handle_interrupt_tx(struct ps3_vuart_port_device *dev)
 
         dev_dbg(&dev->core, "%s:%d\n", __func__, __LINE__);
 
-        spin_lock_irqsave(&dev->tx_list.lock, flags);
+        spin_lock_irqsave(&dev->priv->tx_list.lock, flags);
 
-        list_for_each_entry_safe(lb, n, &dev->tx_list.head, link) {
+        list_for_each_entry_safe(lb, n, &dev->priv->tx_list.head, link) {
 
                 unsigned long bytes_written;
 
@@ -578,7 +620,7 @@ static int ps3_vuart_handle_interrupt_tx(struct ps3_vuart_port_device *dev)
 
         ps3_vuart_disable_interrupt_tx(dev);
 port_full:
-        spin_unlock_irqrestore(&dev->tx_list.lock, flags);
+        spin_unlock_irqrestore(&dev->priv->tx_list.lock, flags);
         dev_dbg(&dev->core, "%s:%d wrote %lxh bytes total\n",
                 __func__, __LINE__, bytes_total);
         return result;
@@ -609,7 +651,7 @@ static int ps3_vuart_handle_interrupt_rx(struct ps3_vuart_port_device *dev)
 
         BUG_ON(!bytes);
 
-        /* add some extra space for recently arrived data */
+        /* Add some extra space for recently arrived data. */
 
         bytes += 128;
 
@@ -624,12 +666,12 @@ static int ps3_vuart_handle_interrupt_rx(struct ps3_vuart_port_device *dev)
         lb->tail = lb->data + bytes;
         lb->dbg_number = ++dbg_number;
 
-        spin_lock_irqsave(&dev->rx_list.lock, flags);
-        list_add_tail(&lb->link, &dev->rx_list.head);
-        dev->rx_list.bytes_held += bytes;
-        spin_unlock_irqrestore(&dev->rx_list.lock, flags);
+        spin_lock_irqsave(&dev->priv->rx_list.lock, flags);
+        list_add_tail(&lb->link, &dev->priv->rx_list.head);
+        dev->priv->rx_list.bytes_held += bytes;
+        spin_unlock_irqrestore(&dev->priv->rx_list.lock, flags);
 
-        dev_dbg(&dev->core, "%s:%d: queued buf_%lu, %lxh bytes\n",
+        dev_dbg(&dev->core, "%s:%d: buf_%lu: queued %lxh bytes\n",
                 __func__, __LINE__, lb->dbg_number, bytes);
 
         return 0;
@@ -656,7 +698,7 @@ static int ps3_vuart_handle_port_interrupt(struct ps3_vuart_port_device *dev)
         int result;
         unsigned long status;
 
-        result = ps3_vuart_get_interrupt_mask(dev, &status);
+        result = ps3_vuart_get_interrupt_status(dev, &status);
 
         if (result)
                 return result;
@@ -665,21 +707,21 @@ static int ps3_vuart_handle_port_interrupt(struct ps3_vuart_port_device *dev)
                 status);
 
         if (status & INTERRUPT_MASK_DISCONNECT) {
-                dev->stats.disconnect_interrupts++;
+                dev->priv->stats.disconnect_interrupts++;
                 result = ps3_vuart_handle_interrupt_disconnect(dev);
                 if (result)
                         ps3_vuart_disable_interrupt_disconnect(dev);
         }
 
         if (status & INTERRUPT_MASK_TX) {
-                dev->stats.tx_interrupts++;
+                dev->priv->stats.tx_interrupts++;
                 result = ps3_vuart_handle_interrupt_tx(dev);
                 if (result)
                         ps3_vuart_disable_interrupt_tx(dev);
         }
 
         if (status & INTERRUPT_MASK_RX) {
-                dev->stats.rx_interrupts++;
+                dev->priv->stats.rx_interrupts++;
                 result = ps3_vuart_handle_interrupt_rx(dev);
                 if (result)
                         ps3_vuart_disable_interrupt_rx(dev);
@@ -688,12 +730,13 @@ static int ps3_vuart_handle_port_interrupt(struct ps3_vuart_port_device *dev)
         return 0;
 }
 
-struct vuart_private {
-        unsigned int in_use;
+struct vuart_bus_priv {
+        const struct ports_bmp bmp;
         unsigned int virq;
+        struct semaphore probe_mutex;
+        int use_count;
         struct ps3_vuart_port_device *devices[PORT_COUNT];
-        const struct ports_bmp bmp;
-};
+} static vuart_bus_priv;
 
 /**
  * ps3_vuart_irq_handler - first stage interrupt handler
@@ -705,25 +748,25 @@ struct vuart_private {
 
 static irqreturn_t ps3_vuart_irq_handler(int irq, void *_private)
 {
-        struct vuart_private *private;
+        struct vuart_bus_priv *bus_priv;
 
         BUG_ON(!_private);
-        private = (struct vuart_private *)_private;
+        bus_priv = (struct vuart_bus_priv *)_private;
 
         while (1) {
                 unsigned int port;
 
-                dump_ports_bmp(&private->bmp);
+                dump_ports_bmp(&bus_priv->bmp);
 
-                port = (BITS_PER_LONG - 1) - __ilog2(private->bmp.status);
+                port = (BITS_PER_LONG - 1) - __ilog2(bus_priv->bmp.status);
 
                 if (port == BITS_PER_LONG)
                         break;
 
                 BUG_ON(port >= PORT_COUNT);
-                BUG_ON(!private->devices[port]);
+                BUG_ON(!bus_priv->devices[port]);
 
-                ps3_vuart_handle_port_interrupt(private->devices[port]);
+                ps3_vuart_handle_port_interrupt(bus_priv->devices[port]);
         }
 
         return IRQ_HANDLED;
@@ -744,12 +787,10 @@ static int ps3_vuart_match(struct device *_dev, struct device_driver *_drv)
         return result;
 }
 
-static struct vuart_private vuart_private;
-
 static int ps3_vuart_probe(struct device *_dev)
 {
         int result;
-        unsigned long tmp;
+        unsigned int port_number;
         struct ps3_vuart_port_device *dev = to_ps3_vuart_port_device(_dev);
         struct ps3_vuart_port_driver *drv =
                 to_ps3_vuart_port_driver(_dev->driver);
@@ -758,7 +799,12 @@ static int ps3_vuart_probe(struct device *_dev)
 
         BUG_ON(!drv);
 
-        result = ps3_vuart_match_id_to_port(dev->match_id, &dev->port_number);
+        down(&vuart_bus_priv.probe_mutex);
+
+        /* Setup vuart_bus_priv.devices[]. */
+
+        result = ps3_vuart_match_id_to_port(dev->match_id,
+                &port_number);
 
         if (result) {
                 dev_dbg(&dev->core, "%s:%d: unknown match_id (%d)\n",
@@ -767,24 +813,36 @@ static int ps3_vuart_probe(struct device *_dev)
                 goto fail_match;
         }
 
-        if (vuart_private.devices[dev->port_number]) {
+        if (vuart_bus_priv.devices[port_number]) {
                 dev_dbg(&dev->core, "%s:%d: port busy (%d)\n", __func__,
-                        __LINE__, dev->port_number);
+                        __LINE__, port_number);
                 result = -EBUSY;
                 goto fail_match;
         }
 
-        vuart_private.devices[dev->port_number] = dev;
+        vuart_bus_priv.devices[port_number] = dev;
+
+        /* Setup dev->priv. */
+
+        dev->priv = kzalloc(sizeof(struct ps3_vuart_port_priv), GFP_KERNEL);
+
+        if (!dev->priv) {
+                result = -ENOMEM;
+                goto fail_alloc;
+        }
+
+        dev->priv->port_number = port_number;
 
-        INIT_LIST_HEAD(&dev->tx_list.head);
-        spin_lock_init(&dev->tx_list.lock);
-        INIT_LIST_HEAD(&dev->rx_list.head);
-        spin_lock_init(&dev->rx_list.lock);
+        INIT_LIST_HEAD(&dev->priv->tx_list.head);
+        spin_lock_init(&dev->priv->tx_list.lock);
+
+        INIT_LIST_HEAD(&dev->priv->rx_list.head);
+        spin_lock_init(&dev->priv->rx_list.lock);
+
+        if (++vuart_bus_priv.use_count == 1) {
 
-        vuart_private.in_use++;
-        if (vuart_private.in_use == 1) {
                 result = ps3_alloc_vuart_irq(PS3_BINDING_CPU_ANY,
-                        (void*)&vuart_private.bmp.status, &vuart_private.virq);
+                        (void*)&vuart_bus_priv.bmp.status, &vuart_bus_priv.virq);
 
                 if (result) {
                         dev_dbg(&dev->core,
@@ -794,8 +852,8 @@ static int ps3_vuart_probe(struct device *_dev)
                         goto fail_alloc_irq;
                 }
 
-                result = request_irq(vuart_private.virq, ps3_vuart_irq_handler,
-                        IRQF_DISABLED, "vuart", &vuart_private);
+                result = request_irq(vuart_bus_priv.virq, ps3_vuart_irq_handler,
+                        IRQF_DISABLED, "vuart", &vuart_bus_priv);
 
                 if (result) {
                         dev_info(&dev->core, "%s:%d: request_irq failed (%d)\n",
@@ -804,10 +862,11 @@ static int ps3_vuart_probe(struct device *_dev)
                 }
         }
 
-        ps3_vuart_set_interrupt_mask(dev, INTERRUPT_MASK_RX);
-
         /* clear stale pending interrupts */
-        ps3_vuart_get_interrupt_mask(dev, &tmp);
+
+        ps3_vuart_clear_rx_bytes(dev, 0);
+
+        ps3_vuart_set_interrupt_mask(dev, INTERRUPT_MASK_RX);
 
         ps3_vuart_set_triggers(dev, 1, 1);
 
@@ -822,20 +881,27 @@ static int ps3_vuart_probe(struct device *_dev)
         if (result) {
                 dev_dbg(&dev->core, "%s:%d: drv->probe failed\n",
                         __func__, __LINE__);
+                down(&vuart_bus_priv.probe_mutex);
                 goto fail_probe;
         }
 
+        up(&vuart_bus_priv.probe_mutex);
+
         return result;
 
 fail_probe:
+        ps3_vuart_set_interrupt_mask(dev, 0);
 fail_request_irq:
-        vuart_private.in_use--;
-        if (!vuart_private.in_use) {
-                ps3_free_vuart_irq(vuart_private.virq);
-                vuart_private.virq = NO_IRQ;
-        }
+        ps3_free_vuart_irq(vuart_bus_priv.virq);
+        vuart_bus_priv.virq = NO_IRQ;
 fail_alloc_irq:
+        --vuart_bus_priv.use_count;
+        kfree(dev->priv);
+        dev->priv = NULL;
+fail_alloc:
+        vuart_bus_priv.devices[port_number] = 0;
 fail_match:
+        up(&vuart_bus_priv.probe_mutex);
         dev_dbg(&dev->core, "%s:%d failed\n", __func__, __LINE__);
         return result;
 }
@@ -846,10 +912,12 @@ static int ps3_vuart_remove(struct device *_dev)
         struct ps3_vuart_port_driver *drv =
                 to_ps3_vuart_port_driver(_dev->driver);
 
+        down(&vuart_bus_priv.probe_mutex);
+
         dev_dbg(&dev->core, "%s:%d: %s\n", __func__, __LINE__,
                 dev->core.bus_id);
 
-        BUG_ON(vuart_private.in_use < 1);
+        BUG_ON(vuart_bus_priv.use_count < 1);
 
         if (drv->remove)
                 drv->remove(dev);
@@ -857,13 +925,19 @@ static int ps3_vuart_remove(struct device *_dev)
                 dev_dbg(&dev->core, "%s:%d: %s no remove method\n", __func__,
                         __LINE__, dev->core.bus_id);
 
-        vuart_private.in_use--;
+        vuart_bus_priv.devices[dev->priv->port_number] = 0;
 
-        if (!vuart_private.in_use) {
-                free_irq(vuart_private.virq, &vuart_private);
-                ps3_free_vuart_irq(vuart_private.virq);
-                vuart_private.virq = NO_IRQ;
+        if (--vuart_bus_priv.use_count == 0) {
+                BUG();
+                free_irq(vuart_bus_priv.virq, &vuart_bus_priv);
+                ps3_free_vuart_irq(vuart_bus_priv.virq);
+                vuart_bus_priv.virq = NO_IRQ;
         }
+
+        kfree(dev->priv);
+        dev->priv = NULL;
+
+        up(&vuart_bus_priv.probe_mutex);
         return 0;
 }
 
@@ -884,12 +958,12 @@ static void ps3_vuart_shutdown(struct device *_dev)
 }
 
 /**
- * ps3_vuart - The vuart instance.
+ * ps3_vuart_bus - The vuart bus instance.
  *
  * The vuart is managed as a bus that port devices connect to.
  */
 
-struct bus_type ps3_vuart = {
+struct bus_type ps3_vuart_bus = {
         .name = "ps3_vuart",
         .match = ps3_vuart_match,
         .probe = ps3_vuart_probe,
@@ -897,24 +971,30 @@ struct bus_type ps3_vuart = {
         .shutdown = ps3_vuart_shutdown,
 };
 
-int __init ps3_vuart_init(void)
+int __init ps3_vuart_bus_init(void)
 {
         int result;
 
         pr_debug("%s:%d:\n", __func__, __LINE__);
-        result = bus_register(&ps3_vuart);
+
+        if (!firmware_has_feature(FW_FEATURE_PS3_LV1))
+                return 0;
+
+        init_MUTEX(&vuart_bus_priv.probe_mutex);
+        result = bus_register(&ps3_vuart_bus);
         BUG_ON(result);
+
         return result;
 }
 
-void __exit ps3_vuart_exit(void)
+void __exit ps3_vuart_bus_exit(void)
 {
         pr_debug("%s:%d:\n", __func__, __LINE__);
-        bus_unregister(&ps3_vuart);
+        bus_unregister(&ps3_vuart_bus);
 }
 
-core_initcall(ps3_vuart_init);
-module_exit(ps3_vuart_exit);
+core_initcall(ps3_vuart_bus_init);
+module_exit(ps3_vuart_bus_exit);
 
 /**
  * ps3_vuart_port_release_device - Remove a vuart port device.
@@ -922,11 +1002,14 @@ module_exit(ps3_vuart_exit);
 
 static void ps3_vuart_port_release_device(struct device *_dev)
 {
-        struct ps3_vuart_port_device *dev = to_ps3_vuart_port_device(_dev);
 #if defined(DEBUG)
-        memset(dev, 0xad, sizeof(struct ps3_vuart_port_device));
+        struct ps3_vuart_port_device *dev = to_ps3_vuart_port_device(_dev);
+
+        dev_dbg(&dev->core, "%s:%d\n", __func__, __LINE__);
+
+        BUG_ON(dev->priv && "forgot to free");
+        memset(&dev->core, 0, sizeof(dev->core));
 #endif
-        kfree(dev);
 }
 
 /**
@@ -935,11 +1018,12 @@ static void ps3_vuart_port_release_device(struct device *_dev)
 
 int ps3_vuart_port_device_register(struct ps3_vuart_port_device *dev)
 {
-        int result;
         static unsigned int dev_count = 1;
 
+        BUG_ON(dev->priv && "forgot to free");
+
         dev->core.parent = NULL;
-        dev->core.bus = &ps3_vuart;
+        dev->core.bus = &ps3_vuart_bus;
         dev->core.release = ps3_vuart_port_release_device;
 
         snprintf(dev->core.bus_id, sizeof(dev->core.bus_id), "vuart_%02x",
@@ -947,9 +1031,7 @@ int ps3_vuart_port_device_register(struct ps3_vuart_port_device *dev)
 
         dev_dbg(&dev->core, "%s:%d register\n", __func__, __LINE__);
 
-        result = device_register(&dev->core);
-
-        return result;
+        return device_register(&dev->core);
 }
 
 EXPORT_SYMBOL_GPL(ps3_vuart_port_device_register);
@@ -963,7 +1045,7 @@ int ps3_vuart_port_driver_register(struct ps3_vuart_port_driver *drv)
         int result;
 
         pr_debug("%s:%d: (%s)\n", __func__, __LINE__, drv->core.name);
-        drv->core.bus = &ps3_vuart;
+        drv->core.bus = &ps3_vuart_bus;
         result = driver_register(&drv->core);
         return result;
 }
@@ -976,6 +1058,7 @@ EXPORT_SYMBOL_GPL(ps3_vuart_port_driver_register);
 
 void ps3_vuart_port_driver_unregister(struct ps3_vuart_port_driver *drv)
 {
+        pr_debug("%s:%d: (%s)\n", __func__, __LINE__, drv->core.name);
         driver_unregister(&drv->core);
 }
 
diff --git a/drivers/ps3/vuart.h b/drivers/ps3/vuart.h
index 2cbf728a3a0b..34b360da9ff9 100644
--- a/drivers/ps3/vuart.h
+++ b/drivers/ps3/vuart.h
@@ -21,6 +21,36 @@
 #if !defined(_PS3_VUART_H)
 #define _PS3_VUART_H
 
+#include <asm/ps3.h>
+
+struct ps3_vuart_stats {
+        unsigned long bytes_written;
+        unsigned long bytes_read;
+        unsigned long tx_interrupts;
+        unsigned long rx_interrupts;
+        unsigned long disconnect_interrupts;
+};
+
+/**
+ * struct ps3_vuart_port_priv - private vuart device data.
+ */
+
+struct ps3_vuart_port_priv {
+        unsigned int port_number;
+        u64 interrupt_mask;
+
+        struct {
+                spinlock_t lock;
+                struct list_head head;
+        } tx_list;
+        struct {
+                unsigned long bytes_held;
+                spinlock_t lock;
+                struct list_head head;
+        } rx_list;
+        struct ps3_vuart_stats stats;
+};
+
 /**
  * struct ps3_vuart_port_driver - a driver for a device on a vuart port
  */