16 files changed, 120 insertions, 70 deletions

diff --git a/drivers/firmware/pcdp.c b/drivers/firmware/pcdp.c
index 839b44a7e08b..53c95c0bbf46 100644
--- a/drivers/firmware/pcdp.c
+++ b/drivers/firmware/pcdp.c
@@ -16,6 +16,7 @@
 #include <linux/console.h>
 #include <linux/efi.h>
 #include <linux/serial.h>
+#include <asm/vga.h>
 #include "pcdp.h"
 
 static int __init
@@ -40,10 +41,27 @@ setup_serial_console(struct pcdp_uart *uart)
 }
 
 static int __init
-setup_vga_console(struct pcdp_vga *vga)
+setup_vga_console(struct pcdp_device *dev)
 {
 #if defined(CONFIG_VT) && defined(CONFIG_VGA_CONSOLE)
-        if (efi_mem_type(0xA0000) == EFI_CONVENTIONAL_MEMORY) {
+        u8 *if_ptr;
+
+        if_ptr = ((u8 *)dev + sizeof(struct pcdp_device));
+        if (if_ptr[0] == PCDP_IF_PCI) {
+                struct pcdp_if_pci if_pci;
+
+                /* struct copy since ifptr might not be correctly aligned */
+
+                memcpy(&if_pci, if_ptr, sizeof(if_pci));
+
+                if (if_pci.trans & PCDP_PCI_TRANS_IOPORT)
+                        vga_console_iobase = if_pci.ioport_tra;
+
+                if (if_pci.trans & PCDP_PCI_TRANS_MMIO)
+                        vga_console_membase = if_pci.mmio_tra;
+        }
+
+        if (efi_mem_type(vga_console_membase + 0xA0000) == EFI_CONVENTIONAL_MEMORY) {
                 printk(KERN_ERR "PCDP: VGA selected, but frame buffer is not MMIO!\n");
                 return -ENODEV;
         }
@@ -95,7 +113,7 @@ efi_setup_pcdp_console(char *cmdline)
              dev = (struct pcdp_device *) ((u8 *) dev + dev->length)) {
                 if (dev->flags & PCDP_PRIMARY_CONSOLE) {
                         if (dev->type == PCDP_CONSOLE_VGA) {
-                                return setup_vga_console((struct pcdp_vga *) dev);
+                                return setup_vga_console(dev);
                         }
                 }
         }
diff --git a/drivers/firmware/pcdp.h b/drivers/firmware/pcdp.h
index 1dc7c88b7b4d..e72cc47de33b 100644
--- a/drivers/firmware/pcdp.h
+++ b/drivers/firmware/pcdp.h
@@ -52,11 +52,34 @@ struct pcdp_uart {
         u32                             clock_rate;
         u8                              pci_prog_intfc;
         u8                              flags;
-};
+} __attribute__((packed));
+
+#define PCDP_IF_PCI     1
+
+/* pcdp_if_pci.trans */
+#define PCDP_PCI_TRANS_IOPORT   0x02
+#define PCDP_PCI_TRANS_MMIO     0x01
+
+struct pcdp_if_pci {
+        u8                      interconnect;
+        u8                      reserved;
+        u16                     length;
+        u8                      segment;
+        u8                      bus;
+        u8                      dev;
+        u8                      fun;
+        u16                     dev_id;
+        u16                     vendor_id;
+        u32                     acpi_interrupt;
+        u64                     mmio_tra;
+        u64                     ioport_tra;
+        u8                      flags;
+        u8                      trans;
+} __attribute__((packed));
 
 struct pcdp_vga {
         u8                      count;          /* address space descriptors */
-};
+} __attribute__((packed));
 
 /* pcdp_device.flags */
 #define PCDP_PRIMARY_CONSOLE    1
@@ -66,7 +89,9 @@ struct pcdp_device {
         u8                      flags;
         u16                     length;
         u16                     efi_index;
-};
+        /* next data is pcdp_if_pci or pcdp_if_acpi (not yet supported) */
+        /* next data is device specific type (currently only pcdp_vga) */
+} __attribute__((packed));
 
 struct pcdp {
         u8                      signature[4];
@@ -81,4 +106,4 @@ struct pcdp {
         u32                     num_uarts;
         struct pcdp_uart        uart[0];        /* actual size is num_uarts */
         /* remainder of table is pcdp_device structures */
-};
+} __attribute__((packed));
diff --git a/drivers/i2c/chips/atxp1.c b/drivers/i2c/chips/atxp1.c
index 5c6597aa2c7f..0bcf82b4c07b 100644
--- a/drivers/i2c/chips/atxp1.c
+++ b/drivers/i2c/chips/atxp1.c
@@ -144,7 +144,7 @@ static ssize_t atxp1_storevcore(struct device *dev, struct device_attribute *att
         if (vid == cvid)
                 return count;
 
-        dev_info(dev, "Setting VCore to %d mV (0x%02x)\n", vcore, vid);
+        dev_dbg(dev, "Setting VCore to %d mV (0x%02x)\n", vcore, vid);
 
         /* Write every 25 mV step to increase stability */
         if (cvid > vid) {
diff --git a/drivers/net/arm/etherh.c b/drivers/net/arm/etherh.c
index 2e28c201dcc0..942a2819576c 100644
--- a/drivers/net/arm/etherh.c
+++ b/drivers/net/arm/etherh.c
@@ -68,7 +68,6 @@ struct etherh_priv {
         void __iomem    *dma_base;
         unsigned int    id;
         void __iomem    *ctrl_port;
-        void __iomem    *base;
         unsigned char   ctrl;
         u32             supported;
 };
@@ -178,7 +177,7 @@ etherh_setif(struct net_device *dev)
         switch (etherh_priv(dev)->id) {
         case PROD_I3_ETHERLAN600:
         case PROD_I3_ETHERLAN600A:
-                addr = etherh_priv(dev)->base + EN0_RCNTHI;
+                addr = (void *)dev->base_addr + EN0_RCNTHI;
 
                 switch (dev->if_port) {
                 case IF_PORT_10BASE2:
@@ -219,7 +218,7 @@ etherh_getifstat(struct net_device *dev)
         switch (etherh_priv(dev)->id) {
         case PROD_I3_ETHERLAN600:
         case PROD_I3_ETHERLAN600A:
-                addr = etherh_priv(dev)->base + EN0_RCNTHI;
+                addr = (void *)dev->base_addr + EN0_RCNTHI;
                 switch (dev->if_port) {
                 case IF_PORT_10BASE2:
                         stat = 1;
@@ -282,7 +281,7 @@ static void
 etherh_reset(struct net_device *dev)
 {
         struct ei_device *ei_local = netdev_priv(dev);
-        void __iomem *addr = etherh_priv(dev)->base;
+        void __iomem *addr = (void *)dev->base_addr;
 
         writeb(E8390_NODMA+E8390_PAGE0+E8390_STOP, addr);
 
@@ -328,7 +327,7 @@ etherh_block_output (struct net_device *dev, int count, const unsigned char *buf
 
         ei_local->dmaing = 1;
 
-        addr = etherh_priv(dev)->base;
+        addr = (void *)dev->base_addr;
         dma_base = etherh_priv(dev)->dma_base;
 
         count = (count + 1) & ~1;
@@ -388,7 +387,7 @@ etherh_block_input (struct net_device *dev, int count, struct sk_buff *skb, int
 
         ei_local->dmaing = 1;
 
-        addr = etherh_priv(dev)->base;
+        addr = (void *)dev->base_addr;
         dma_base = etherh_priv(dev)->dma_base;
 
         buf = skb->data;
@@ -428,7 +427,7 @@ etherh_get_header (struct net_device *dev, struct e8390_pkt_hdr *hdr, int ring_p
 
         ei_local->dmaing = 1;
 
-        addr = etherh_priv(dev)->base;
+        addr = (void *)dev->base_addr;
         dma_base = etherh_priv(dev)->dma_base;
 
         writeb (E8390_NODMA | E8390_PAGE0 | E8390_START, addr + E8390_CMD);
@@ -697,8 +696,7 @@ etherh_probe(struct expansion_card *ec, const struct ecard_id *id)
                 eh->ctrl_port = eh->ioc_fast;
         }
 
-        eh->base = eh->memc + data->ns8390_offset;
-        dev->base_addr = (unsigned long)eh->base;
+        dev->base_addr = (unsigned long)eh->memc + data->ns8390_offset;
         eh->dma_base = eh->memc + data->dataport_offset;
         eh->ctrl_port += data->ctrlport_offset;
 
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 34e75bc8f4cc..9224fc3184ea 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -105,7 +105,7 @@ static struct old_serial_port old_serial_port[] = {
         SERIAL_PORT_DFNS /* defined in asm/serial.h */
 };
 
-#define UART_NR (ARRAY_SIZE(old_serial_port) + CONFIG_SERIAL_8250_NR_UARTS)
+#define UART_NR CONFIG_SERIAL_8250_NR_UARTS
 
 #ifdef CONFIG_SERIAL_8250_RSA
 
@@ -993,21 +993,24 @@ static void autoconfig_irq(struct uart_8250_port *up)
         up->port.irq = (irq > 0) ? irq : 0;
 }
 
+static inline void __stop_tx(struct uart_8250_port *p)
+{
+        if (p->ier & UART_IER_THRI) {
+                p->ier &= ~UART_IER_THRI;
+                serial_out(p, UART_IER, p->ier);
+        }
+}
+
 static void serial8250_stop_tx(struct uart_port *port, unsigned int tty_stop)
 {
         struct uart_8250_port *up = (struct uart_8250_port *)port;
 
-        if (up->ier & UART_IER_THRI) {
-                up->ier &= ~UART_IER_THRI;
-                serial_out(up, UART_IER, up->ier);
-        }
+        __stop_tx(up);
 
         /*
-         * We only do this from uart_stop - if we run out of
-         * characters to send, we don't want to prevent the
-         * FIFO from emptying.
+         * We really want to stop the transmitter from sending.
          */
-        if (up->port.type == PORT_16C950 && tty_stop) {
+        if (up->port.type == PORT_16C950) {
                 up->acr |= UART_ACR_TXDIS;
                 serial_icr_write(up, UART_ACR, up->acr);
         }
@@ -1031,10 +1034,11 @@ static void serial8250_start_tx(struct uart_port *port, unsigned int tty_start)
                                 transmit_chars(up);
                 }
         }
+
         /*
-         * We only do this from uart_start
+         * Re-enable the transmitter if we disabled it.
          */
-        if (tty_start && up->port.type == PORT_16C950) {
+        if (up->port.type == PORT_16C950 && up->acr & UART_ACR_TXDIS) {
                 up->acr &= ~UART_ACR_TXDIS;
                 serial_icr_write(up, UART_ACR, up->acr);
         }
@@ -1155,7 +1159,7 @@ static _INLINE_ void transmit_chars(struct uart_8250_port *up)
                 return;
         }
         if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
-                serial8250_stop_tx(&up->port, 0);
+                __stop_tx(up);
                 return;
         }
 
@@ -1174,7 +1178,7 @@ static _INLINE_ void transmit_chars(struct uart_8250_port *up)
         DEBUG_INTR("THRE...");
 
         if (uart_circ_empty(xmit))
-                serial8250_stop_tx(&up->port, 0);
+                __stop_tx(up);
 }
 
 static _INLINE_ void check_modem_status(struct uart_8250_port *up)
@@ -1376,13 +1380,10 @@ static unsigned int serial8250_tx_empty(struct uart_port *port)
 static unsigned int serial8250_get_mctrl(struct uart_port *port)
 {
         struct uart_8250_port *up = (struct uart_8250_port *)port;
-        unsigned long flags;
         unsigned char status;
         unsigned int ret;
 
-        spin_lock_irqsave(&up->port.lock, flags);
         status = serial_in(up, UART_MSR);
-        spin_unlock_irqrestore(&up->port.lock, flags);
 
         ret = 0;
         if (status & UART_MSR_DCD)
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index e879bce160df..e0d0a470ddfc 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -86,7 +86,7 @@ config SERIAL_8250_ACPI
           namespace, say Y here.  If unsure, say N.
 
 config SERIAL_8250_NR_UARTS
-        int "Maximum number of non-legacy 8250/16550 serial ports"
+        int "Maximum number of 8250/16550 serial ports"
         depends on SERIAL_8250
         default "4"
         help
diff --git a/drivers/serial/au1x00_uart.c b/drivers/serial/au1x00_uart.c
index 5400dc2c087e..6104aeef1243 100644
--- a/drivers/serial/au1x00_uart.c
+++ b/drivers/serial/au1x00_uart.c
@@ -556,13 +556,10 @@ static unsigned int serial8250_tx_empty(struct uart_port *port)
 static unsigned int serial8250_get_mctrl(struct uart_port *port)
 {
         struct uart_8250_port *up = (struct uart_8250_port *)port;
-        unsigned long flags;
         unsigned char status;
         unsigned int ret;
 
-        spin_lock_irqsave(&up->port.lock, flags);
         status = serial_in(up, UART_MSR);
-        spin_unlock_irqrestore(&up->port.lock, flags);
 
         ret = 0;
         if (status & UART_MSR_DCD)
diff --git a/drivers/serial/ip22zilog.c b/drivers/serial/ip22zilog.c
index 3ea46c069f6f..ea5bf4d4daa3 100644
--- a/drivers/serial/ip22zilog.c
+++ b/drivers/serial/ip22zilog.c
@@ -518,27 +518,28 @@ static irqreturn_t ip22zilog_interrupt(int irq, void *dev_id, struct pt_regs *re
 static __inline__ unsigned char ip22zilog_read_channel_status(struct uart_port *port)
 {
         struct zilog_channel *channel;
-        unsigned long flags;
         unsigned char status;
 
-        spin_lock_irqsave(&port->lock, flags);
-
         channel = ZILOG_CHANNEL_FROM_PORT(port);
         status = readb(&channel->control);
         ZSDELAY();
 
-        spin_unlock_irqrestore(&port->lock, flags);
-
         return status;
 }
 
 /* The port lock is not held.  */
 static unsigned int ip22zilog_tx_empty(struct uart_port *port)
 {
+        unsigned long flags;
         unsigned char status;
         unsigned int ret;
 
+        spin_lock_irqsave(&port->lock, flags);
+
         status = ip22zilog_read_channel_status(port);
+
+        spin_unlock_irqrestore(&port->lock, flags);
+
         if (status & Tx_BUF_EMP)
                 ret = TIOCSER_TEMT;
         else
@@ -547,7 +548,7 @@ static unsigned int ip22zilog_tx_empty(struct uart_port *port)
         return ret;
 }
 
-/* The port lock is not held.  */
+/* The port lock is held and interrupts are disabled.  */
 static unsigned int ip22zilog_get_mctrl(struct uart_port *port)
 {
         unsigned char status;
diff --git a/drivers/serial/mpsc.c b/drivers/serial/mpsc.c
index a2a643318002..e43276c6a954 100644
--- a/drivers/serial/mpsc.c
+++ b/drivers/serial/mpsc.c
@@ -1058,12 +1058,9 @@ mpsc_get_mctrl(struct uart_port *port)
 {
         struct mpsc_port_info *pi = (struct mpsc_port_info *)port;
         u32 mflags, status;
-        ulong iflags;
 
-        spin_lock_irqsave(&pi->port.lock, iflags);
         status = (pi->mirror_regs) ? pi->MPSC_CHR_10_m :
                 readl(pi->mpsc_base + MPSC_CHR_10);
-        spin_unlock_irqrestore(&pi->port.lock, iflags);
 
         mflags = 0;
         if (status & 0x1)
diff --git a/drivers/serial/pmac_zilog.c b/drivers/serial/pmac_zilog.c
index 85abd8a045e0..1c9f71617123 100644
--- a/drivers/serial/pmac_zilog.c
+++ b/drivers/serial/pmac_zilog.c
@@ -604,7 +604,7 @@ static void pmz_set_mctrl(struct uart_port *port, unsigned int mctrl)
 /* 
  * Get Modem Control bits (only the input ones, the core will
  * or that with a cached value of the control ones)
- * The port lock is not held.
+ * The port lock is held and interrupts are disabled.
  */
 static unsigned int pmz_get_mctrl(struct uart_port *port)
 {
@@ -615,7 +615,7 @@ static unsigned int pmz_get_mctrl(struct uart_port *port)
         if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
                 return 0;
 
-        status = pmz_peek_status(to_pmz(port));
+        status = read_zsreg(uap, R0);
 
         ret = 0;
         if (status & DCD)
diff --git a/drivers/serial/pxa.c b/drivers/serial/pxa.c
index 08b08d6ae904..461c81c93207 100644
--- a/drivers/serial/pxa.c
+++ b/drivers/serial/pxa.c
@@ -274,14 +274,11 @@ static unsigned int serial_pxa_tx_empty(struct uart_port *port)
 static unsigned int serial_pxa_get_mctrl(struct uart_port *port)
 {
         struct uart_pxa_port *up = (struct uart_pxa_port *)port;
-        unsigned long flags;
         unsigned char status;
         unsigned int ret;
 
 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
-        spin_lock_irqsave(&up->port.lock, flags);
         status = serial_in(up, UART_MSR);
-        spin_unlock_irqrestore(&up->port.lock, flags);
 
         ret = 0;
         if (status & UART_MSR_DCD)
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index 36b1ae083fb7..139863a787f3 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -182,6 +182,13 @@ static int uart_startup(struct uart_state *state, int init_hw)
                                 uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR);
                 }
 
+                if (info->flags & UIF_CTS_FLOW) {
+                        spin_lock_irq(&port->lock);
+                        if (!(port->ops->get_mctrl(port) & TIOCM_CTS))
+                                info->tty->hw_stopped = 1;
+                        spin_unlock_irq(&port->lock);
+                }
+
                 info->flags |= UIF_INITIALIZED;
 
                 clear_bit(TTY_IO_ERROR, &info->tty->flags);
@@ -828,7 +835,10 @@ static int uart_tiocmget(struct tty_struct *tty, struct file *file)
         if ((!file || !tty_hung_up_p(file)) &&
             !(tty->flags & (1 << TTY_IO_ERROR))) {
                 result = port->mctrl;
+
+                spin_lock_irq(&port->lock);
                 result |= port->ops->get_mctrl(port);
+                spin_unlock_irq(&port->lock);
         }
         up(&state->sem);
 
@@ -1131,6 +1141,16 @@ static void uart_set_termios(struct tty_struct *tty, struct termios *old_termios
                 spin_unlock_irqrestore(&state->port->lock, flags);
         }
 
+        /* Handle turning on CRTSCTS */
+        if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) {
+                spin_lock_irqsave(&state->port->lock, flags);
+                if (!(state->port->ops->get_mctrl(state->port) & TIOCM_CTS)) {
+                        tty->hw_stopped = 1;
+                        state->port->ops->stop_tx(state->port, 0);
+                }
+                spin_unlock_irqrestore(&state->port->lock, flags);
+        }
+
 #if 0
         /*
          * No need to wake up processes in open wait, since they
@@ -1369,6 +1389,7 @@ uart_block_til_ready(struct file *filp, struct uart_state *state)
         DECLARE_WAITQUEUE(wait, current);
         struct uart_info *info = state->info;
         struct uart_port *port = state->port;
+        unsigned int mctrl;
 
         info->blocked_open++;
         state->count--;
@@ -1416,7 +1437,10 @@ uart_block_til_ready(struct file *filp, struct uart_state *state)
                  * and wait for the carrier to indicate that the
                  * modem is ready for us.
                  */
-                if (port->ops->get_mctrl(port) & TIOCM_CAR)
+                spin_lock_irq(&port->lock);
+                mctrl = port->ops->get_mctrl(port);
+                spin_unlock_irq(&port->lock);
+                if (mctrl & TIOCM_CAR)
                         break;
 
                 up(&state->sem);
@@ -1618,7 +1642,9 @@ static int uart_line_info(char *buf, struct uart_driver *drv, int i)
 
         if(capable(CAP_SYS_ADMIN))
         {
+                spin_lock_irq(&port->lock);
                 status = port->ops->get_mctrl(port);
+                spin_unlock_irq(&port->lock);
 
                 ret += sprintf(buf + ret, " tx:%d rx:%d",
                                 port->icount.tx, port->icount.rx);
diff --git a/drivers/serial/serial_txx9.c b/drivers/serial/serial_txx9.c
index 3f1051a4a13f..d085030df70b 100644
--- a/drivers/serial/serial_txx9.c
+++ b/drivers/serial/serial_txx9.c
@@ -442,13 +442,10 @@ static unsigned int serial_txx9_tx_empty(struct uart_port *port)
 static unsigned int serial_txx9_get_mctrl(struct uart_port *port)
 {
         struct uart_txx9_port *up = (struct uart_txx9_port *)port;
-        unsigned long flags;
         unsigned int ret;
 
-        spin_lock_irqsave(&up->port.lock, flags);
         ret =  ((sio_in(up, TXX9_SIFLCR) & TXX9_SIFLCR_RTSSC) ? 0 : TIOCM_RTS)
                 | ((sio_in(up, TXX9_SICISR) & TXX9_SICISR_CTSS) ? 0 : TIOCM_CTS);
-        spin_unlock_irqrestore(&up->port.lock, flags);
 
         return ret;
 }
diff --git a/drivers/serial/sunsab.c b/drivers/serial/sunsab.c
index 10e2990a40d4..8d198880756a 100644
--- a/drivers/serial/sunsab.c
+++ b/drivers/serial/sunsab.c
@@ -426,18 +426,15 @@ static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
                 sunsab_tx_idle(up);
 }
 
-/* port->lock is not held.  */
+/* port->lock is held by caller and interrupts are disabled.  */
 static unsigned int sunsab_get_mctrl(struct uart_port *port)
 {
         struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
-        unsigned long flags;
         unsigned char val;
         unsigned int result;
 
         result = 0;
 
-        spin_lock_irqsave(&up->port.lock, flags);
-
         val = readb(&up->regs->r.pvr);
         result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
 
@@ -447,8 +444,6 @@ static unsigned int sunsab_get_mctrl(struct uart_port *port)
         val = readb(&up->regs->r.star);
         result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
 
-        spin_unlock_irqrestore(&up->port.lock, flags);
-
         return result;
 }
 
diff --git a/drivers/serial/sunsu.c b/drivers/serial/sunsu.c
index ddc97c905e14..d57a3553aea3 100644
--- a/drivers/serial/sunsu.c
+++ b/drivers/serial/sunsu.c
@@ -572,13 +572,10 @@ static unsigned int sunsu_tx_empty(struct uart_port *port)
 static unsigned int sunsu_get_mctrl(struct uart_port *port)
 {
         struct uart_sunsu_port *up = (struct uart_sunsu_port *) port;
-        unsigned long flags;
         unsigned char status;
         unsigned int ret;
 
-        spin_lock_irqsave(&up->port.lock, flags);
         status = serial_in(up, UART_MSR);
-        spin_unlock_irqrestore(&up->port.lock, flags);
 
         ret = 0;
         if (status & UART_MSR_DCD)
diff --git a/drivers/serial/sunzilog.c b/drivers/serial/sunzilog.c
index 8e65206d3d76..bff42a7b89d0 100644
--- a/drivers/serial/sunzilog.c
+++ b/drivers/serial/sunzilog.c
@@ -610,27 +610,28 @@ static irqreturn_t sunzilog_interrupt(int irq, void *dev_id, struct pt_regs *reg
 static __inline__ unsigned char sunzilog_read_channel_status(struct uart_port *port)
 {
         struct zilog_channel __iomem *channel;
-        unsigned long flags;
         unsigned char status;
 
-        spin_lock_irqsave(&port->lock, flags);
-
         channel = ZILOG_CHANNEL_FROM_PORT(port);
         status = sbus_readb(&channel->control);
         ZSDELAY();
 
-        spin_unlock_irqrestore(&port->lock, flags);
-
         return status;
 }
 
 /* The port lock is not held.  */
 static unsigned int sunzilog_tx_empty(struct uart_port *port)
 {
+        unsigned long flags;
         unsigned char status;
         unsigned int ret;
 
+        spin_lock_irqsave(&port->lock, flags);
+
         status = sunzilog_read_channel_status(port);
+
+        spin_unlock_irqrestore(&port->lock, flags);
+
         if (status & Tx_BUF_EMP)
                 ret = TIOCSER_TEMT;
         else
@@ -639,7 +640,7 @@ static unsigned int sunzilog_tx_empty(struct uart_port *port)
         return ret;
 }
 
-/* The port lock is not held.  */
+/* The port lock is held and interrupts are disabled.  */
 static unsigned int sunzilog_get_mctrl(struct uart_port *port)
 {
         unsigned char status;