1 files changed, 188 insertions, 101 deletions

diff --git a/drivers/serial/dz.c b/drivers/serial/dz.c
index c054c1bd8b24..116211fcd36f 100644
--- a/drivers/serial/dz.c
+++ b/drivers/serial/dz.c
@@ -39,6 +39,7 @@
 #include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
+#include <linux/ioport.h>
 #include <linux/kernel.h>
 #include <linux/major.h>
 #include <linux/module.h>
@@ -47,7 +48,9 @@
 #include <linux/sysrq.h>
 #include <linux/tty.h>
 
+#include <asm/atomic.h>
 #include <asm/bootinfo.h>
+#include <asm/io.h>
 #include <asm/system.h>
 
 #include <asm/dec/interrupts.h>
@@ -55,18 +58,32 @@
 #include <asm/dec/kn02.h>
 #include <asm/dec/machtype.h>
 #include <asm/dec/prom.h>
+#include <asm/dec/system.h>
 
 #include "dz.h"
 
-static char *dz_name = "DECstation DZ serial driver version ";
-static char *dz_version = "1.03";
+
+MODULE_DESCRIPTION("DECstation DZ serial driver");
+MODULE_LICENSE("GPL");
+
+
+static char dz_name[] __initdata = "DECstation DZ serial driver version ";
+static char dz_version[] __initdata = "1.04";
 
 struct dz_port {
+        struct dz_mux           *mux;
         struct uart_port        port;
         unsigned int            cflag;
 };
 
-static struct dz_port dz_ports[DZ_NB_PORT];
+struct dz_mux {
+        struct dz_port          dport[DZ_NB_PORT];
+        atomic_t                map_guard;
+        atomic_t                irq_guard;
+        int                     initialised;
+};
+
+static struct dz_mux dz_mux;
 
 static inline struct dz_port *to_dport(struct uart_port *uport)
 {
@@ -82,21 +99,18 @@ static inline struct dz_port *to_dport(struct uart_port *uport)
  * ------------------------------------------------------------
  */
 
-static inline unsigned short dz_in(struct dz_port *dport, unsigned offset)
+static u16 dz_in(struct dz_port *dport, unsigned offset)
 {
-        volatile unsigned short *addr =
-                (volatile unsigned short *) (dport->port.membase + offset);
+        void __iomem *addr = dport->port.membase + offset;
 
-        return *addr;
+        return readw(addr);
 }
 
-static inline void dz_out(struct dz_port *dport, unsigned offset,
-                          unsigned short value)
+static void dz_out(struct dz_port *dport, unsigned offset, u16 value)
 {
-        volatile unsigned short *addr =
-                (volatile unsigned short *) (dport->port.membase + offset);
+        void __iomem *addr = dport->port.membase + offset;
 
-        *addr = value;
+        writew(value, addr);
 }
 
 /*
@@ -112,7 +126,7 @@ static inline void dz_out(struct dz_port *dport, unsigned offset,
 static void dz_stop_tx(struct uart_port *uport)
 {
         struct dz_port *dport = to_dport(uport);
-        unsigned short tmp, mask = 1 << dport->port.line;
+        u16 tmp, mask = 1 << dport->port.line;
 
         tmp = dz_in(dport, DZ_TCR);     /* read the TX flag */
         tmp &= ~mask;                   /* clear the TX flag */
@@ -122,7 +136,7 @@ static void dz_stop_tx(struct uart_port *uport)
 static void dz_start_tx(struct uart_port *uport)
 {
         struct dz_port *dport = to_dport(uport);
-        unsigned short tmp, mask = 1 << dport->port.line;
+        u16 tmp, mask = 1 << dport->port.line;
 
         tmp = dz_in(dport, DZ_TCR);     /* read the TX flag */
         tmp |= mask;                    /* set the TX flag */
@@ -137,7 +151,7 @@ static void dz_stop_rx(struct uart_port *uport)
         dz_out(dport, DZ_LPR, dport->cflag);
 }
 
-static void dz_enable_ms(struct uart_port *port)
+static void dz_enable_ms(struct uart_port *uport)
 {
         /* nothing to do */
 }
@@ -169,19 +183,19 @@ static void dz_enable_ms(struct uart_port *port)
  * This routine deals with inputs from any lines.
  * ------------------------------------------------------------
  */
-static inline void dz_receive_chars(struct dz_port *dport_in)
+static inline void dz_receive_chars(struct dz_mux *mux)
 {
         struct uart_port *uport;
-        struct dz_port *dport;
+        struct dz_port *dport = &mux->dport[0];
         struct tty_struct *tty = NULL;
         struct uart_icount *icount;
         int lines_rx[DZ_NB_PORT] = { [0 ... DZ_NB_PORT - 1] = 0 };
-        unsigned short status;
         unsigned char ch, flag;
+        u16 status;
         int i;
 
-        while ((status = dz_in(dport_in, DZ_RBUF)) & DZ_DVAL) {
-                dport = &dz_ports[LINE(status)];
+        while ((status = dz_in(dport, DZ_RBUF)) & DZ_DVAL) {
+                dport = &mux->dport[LINE(status)];
                 uport = &dport->port;
                 tty = uport->info->tty;         /* point to the proper dev */
 
@@ -235,7 +249,7 @@ static inline void dz_receive_chars(struct dz_port *dport_in)
         }
         for (i = 0; i < DZ_NB_PORT; i++)
                 if (lines_rx[i])
-                        tty_flip_buffer_push(dz_ports[i].port.info->tty);
+                        tty_flip_buffer_push(mux->dport[i].port.info->tty);
 }
 
 /*
@@ -245,15 +259,15 @@ static inline void dz_receive_chars(struct dz_port *dport_in)
  * This routine deals with outputs to any lines.
  * ------------------------------------------------------------
  */
-static inline void dz_transmit_chars(struct dz_port *dport_in)
+static inline void dz_transmit_chars(struct dz_mux *mux)
 {
-        struct dz_port *dport;
+        struct dz_port *dport = &mux->dport[0];
         struct circ_buf *xmit;
-        unsigned short status;
         unsigned char tmp;
+        u16 status;
 
-        status = dz_in(dport_in, DZ_CSR);
-        dport = &dz_ports[LINE(status)];
+        status = dz_in(dport, DZ_CSR);
+        dport = &mux->dport[LINE(status)];
         xmit = &dport->port.info->xmit;
 
         if (dport->port.x_char) {               /* XON/XOFF chars */
@@ -305,7 +319,7 @@ static inline void check_modem_status(struct dz_port *dport)
          * 1. No status change interrupt; use a timer.
          * 2. Handle the 3100/5000 as appropriate. --macro
          */
-        unsigned short status;
+        u16 status;
 
         /* If not the modem line just return.  */
         if (dport->port.line != DZ_MODEM)
@@ -326,19 +340,20 @@ static inline void check_modem_status(struct dz_port *dport)
  * It deals with the multiple ports.
  * ------------------------------------------------------------
  */
-static irqreturn_t dz_interrupt(int irq, void *dev)
+static irqreturn_t dz_interrupt(int irq, void *dev_id)
 {
-        struct dz_port *dport = dev;
-        unsigned short status;
+        struct dz_mux *mux = dev_id;
+        struct dz_port *dport = &mux->dport[0];
+        u16 status;
 
         /* get the reason why we just got an irq */
         status = dz_in(dport, DZ_CSR);
 
         if ((status & (DZ_RDONE | DZ_RIE)) == (DZ_RDONE | DZ_RIE))
-                dz_receive_chars(dport);
+                dz_receive_chars(mux);
 
         if ((status & (DZ_TRDY | DZ_TIE)) == (DZ_TRDY | DZ_TIE))
-                dz_transmit_chars(dport);
+                dz_transmit_chars(mux);
 
         return IRQ_HANDLED;
 }
@@ -371,7 +386,7 @@ static void dz_set_mctrl(struct uart_port *uport, unsigned int mctrl)
          * FIXME: Handle the 3100/5000 as appropriate. --macro
          */
         struct dz_port *dport = to_dport(uport);
-        unsigned short tmp;
+        u16 tmp;
 
         if (dport->port.line == DZ_MODEM) {
                 tmp = dz_in(dport, DZ_TCR);
@@ -393,14 +408,29 @@ static void dz_set_mctrl(struct uart_port *uport, unsigned int mctrl)
 static int dz_startup(struct uart_port *uport)
 {
         struct dz_port *dport = to_dport(uport);
+        struct dz_mux *mux = dport->mux;
         unsigned long flags;
-        unsigned short tmp;
+        int irq_guard;
+        int ret;
+        u16 tmp;
+
+        irq_guard = atomic_add_return(1, &mux->irq_guard);
+        if (irq_guard != 1)
+                return 0;
+
+        ret = request_irq(dport->port.irq, dz_interrupt,
+                          IRQF_SHARED, "dz", mux);
+        if (ret) {
+                atomic_add(-1, &mux->irq_guard);
+                printk(KERN_ERR "dz: Cannot get IRQ %d!\n", dport->port.irq);
+                return ret;
+        }
 
         spin_lock_irqsave(&dport->port.lock, flags);
 
-        /* enable the interrupt and the scanning */
+        /* Enable interrupts.  */
         tmp = dz_in(dport, DZ_CSR);
-        tmp |= DZ_RIE | DZ_TIE | DZ_MSE;
+        tmp |= DZ_RIE | DZ_TIE;
         dz_out(dport, DZ_CSR, tmp);
 
         spin_unlock_irqrestore(&dport->port.lock, flags);
@@ -419,11 +449,24 @@ static int dz_startup(struct uart_port *uport)
 static void dz_shutdown(struct uart_port *uport)
 {
         struct dz_port *dport = to_dport(uport);
+        struct dz_mux *mux = dport->mux;
         unsigned long flags;
+        int irq_guard;
+        u16 tmp;
 
         spin_lock_irqsave(&dport->port.lock, flags);
         dz_stop_tx(&dport->port);
         spin_unlock_irqrestore(&dport->port.lock, flags);
+
+        irq_guard = atomic_add_return(-1, &mux->irq_guard);
+        if (!irq_guard) {
+                /* Disable interrupts.  */
+                tmp = dz_in(dport, DZ_CSR);
+                tmp &= ~(DZ_RIE | DZ_TIE);
+                dz_out(dport, DZ_CSR, tmp);
+
+                free_irq(dport->port.irq, mux);
+        }
 }
 
 /*
@@ -507,6 +550,24 @@ static int dz_encode_baud_rate(unsigned int baud)
         }
 }
 
+
+static void dz_reset(struct dz_port *dport)
+{
+        struct dz_mux *mux = dport->mux;
+
+        if (mux->initialised)
+                return;
+
+        dz_out(dport, DZ_CSR, DZ_CLR);
+        while (dz_in(dport, DZ_CSR) & DZ_CLR);
+        iob();
+
+        /* Enable scanning.  */
+        dz_out(dport, DZ_CSR, DZ_MSE);
+
+        mux->initialised = 1;
+}
+
 static void dz_set_termios(struct uart_port *uport, struct ktermios *termios,
                            struct ktermios *old_termios)
 {
@@ -581,36 +642,86 @@ static void dz_set_termios(struct uart_port *uport, struct ktermios *termios,
         spin_unlock_irqrestore(&dport->port.lock, flags);
 }
 
-static const char *dz_type(struct uart_port *port)
+static const char *dz_type(struct uart_port *uport)
 {
         return "DZ";
 }
 
-static void dz_release_port(struct uart_port *port)
+static void dz_release_port(struct uart_port *uport)
 {
-        /* nothing to do */
+        struct dz_mux *mux = to_dport(uport)->mux;
+        int map_guard;
+
+        iounmap(uport->membase);
+        uport->membase = NULL;
+
+        map_guard = atomic_add_return(-1, &mux->map_guard);
+        if (!map_guard)
+                release_mem_region(uport->mapbase, dec_kn_slot_size);
 }
 
-static int dz_request_port(struct uart_port *port)
+static int dz_map_port(struct uart_port *uport)
 {
+        if (!uport->membase)
+                uport->membase = ioremap_nocache(uport->mapbase,
+                                                 dec_kn_slot_size);
+        if (!uport->membase) {
+                printk(KERN_ERR "dz: Cannot map MMIO\n");
+                return -ENOMEM;
+        }
         return 0;
 }
 
-static void dz_config_port(struct uart_port *port, int flags)
+static int dz_request_port(struct uart_port *uport)
 {
-        if (flags & UART_CONFIG_TYPE)
-                port->type = PORT_DZ;
+        struct dz_mux *mux = to_dport(uport)->mux;
+        int map_guard;
+        int ret;
+
+        map_guard = atomic_add_return(1, &mux->map_guard);
+        if (map_guard == 1) {
+                if (!request_mem_region(uport->mapbase, dec_kn_slot_size,
+                                        "dz")) {
+                        atomic_add(-1, &mux->map_guard);
+                        printk(KERN_ERR
+                               "dz: Unable to reserve MMIO resource\n");
+                        return -EBUSY;
+                }
+        }
+        ret = dz_map_port(uport);
+        if (ret) {
+                map_guard = atomic_add_return(-1, &mux->map_guard);
+                if (!map_guard)
+                        release_mem_region(uport->mapbase, dec_kn_slot_size);
+                return ret;
+        }
+        return 0;
+}
+
+static void dz_config_port(struct uart_port *uport, int flags)
+{
+        struct dz_port *dport = to_dport(uport);
+
+        if (flags & UART_CONFIG_TYPE) {
+                if (dz_request_port(uport))
+                        return;
+
+                uport->type = PORT_DZ;
+
+                dz_reset(dport);
+        }
 }
 
 /*
- * verify the new serial_struct (for TIOCSSERIAL).
+ * Verify the new serial_struct (for TIOCSSERIAL).
  */
-static int dz_verify_port(struct uart_port *port, struct serial_struct *ser)
+static int dz_verify_port(struct uart_port *uport, struct serial_struct *ser)
 {
         int ret = 0;
+
         if (ser->type != PORT_UNKNOWN && ser->type != PORT_DZ)
                 ret = -EINVAL;
-        if (ser->irq != port->irq)
+        if (ser->irq != uport->irq)
                 ret = -EINVAL;
         return ret;
 }
@@ -637,40 +748,32 @@ static struct uart_ops dz_ops = {
 static void __init dz_init_ports(void)
 {
         static int first = 1;
-        struct dz_port *dport;
         unsigned long base;
-        int i;
+        int line;
 
         if (!first)
                 return;
         first = 0;
 
-        if (mips_machtype == MACH_DS23100 ||
-            mips_machtype == MACH_DS5100)
-                base = CKSEG1ADDR(KN01_SLOT_BASE + KN01_DZ11);
+        if (mips_machtype == MACH_DS23100 || mips_machtype == MACH_DS5100)
+                base = dec_kn_slot_base + KN01_DZ11;
         else
-                base = CKSEG1ADDR(KN02_SLOT_BASE + KN02_DZ11);
-
-        for (i = 0, dport = dz_ports; i < DZ_NB_PORT; i++, dport++) {
-                spin_lock_init(&dport->port.lock);
-                dport->port.membase     = (char *) base;
-                dport->port.iotype      = UPIO_MEM;
-                dport->port.irq         = dec_interrupt[DEC_IRQ_DZ11];
-                dport->port.line        = i;
-                dport->port.fifosize    = 1;
-                dport->port.ops         = &dz_ops;
-                dport->port.flags       = UPF_BOOT_AUTOCONF;
-        }
-}
+                base = dec_kn_slot_base + KN02_DZ11;
 
-static void dz_reset(struct dz_port *dport)
-{
-        dz_out(dport, DZ_CSR, DZ_CLR);
-        while (dz_in(dport, DZ_CSR) & DZ_CLR);
-        iob();
+        for (line = 0; line < DZ_NB_PORT; line++) {
+                struct dz_port *dport = &dz_mux.dport[line];
+                struct uart_port *uport = &dport->port;
 
-        /* enable scanning */
-        dz_out(dport, DZ_CSR, DZ_MSE);
+                dport->mux      = &dz_mux;
+
+                uport->irq      = dec_interrupt[DEC_IRQ_DZ11];
+                uport->fifosize = 1;
+                uport->iotype   = UPIO_MEM;
+                uport->flags    = UPF_BOOT_AUTOCONF;
+                uport->ops      = &dz_ops;
+                uport->line     = line;
+                uport->mapbase  = base;
+        }
 }
 
 #ifdef CONFIG_SERIAL_DZ_CONSOLE
@@ -737,7 +840,7 @@ static void dz_console_print(struct console *co,
                              const char *str,
                              unsigned int count)
 {
-        struct dz_port *dport = &dz_ports[co->index];
+        struct dz_port *dport = &dz_mux.dport[co->index];
 #ifdef DEBUG_DZ
         prom_printf((char *) str);
 #endif
@@ -746,17 +849,23 @@ static void dz_console_print(struct console *co,
 
 static int __init dz_console_setup(struct console *co, char *options)
 {
-        struct dz_port *dport = &dz_ports[co->index];
+        struct dz_port *dport = &dz_mux.dport[co->index];
+        struct uart_port *uport = &dport->port;
         int baud = 9600;
         int bits = 8;
         int parity = 'n';
         int flow = 'n';
+        int ret;
 
-        if (options)
-                uart_parse_options(options, &baud, &parity, &bits, &flow);
+        ret = dz_map_port(uport);
+        if (ret)
+                return ret;
 
         dz_reset(dport);
 
+        if (options)
+                uart_parse_options(options, &baud, &parity, &bits, &flow);
+
         return uart_set_options(&dport->port, co, baud, parity, bits, flow);
 }
 
@@ -809,36 +918,14 @@ static int __init dz_init(void)
 
         dz_init_ports();
 
-#ifndef CONFIG_SERIAL_DZ_CONSOLE
-        /* reset the chip */
-        dz_reset(&dz_ports[0]);
-#endif
-
         ret = uart_register_driver(&dz_reg);
-        if (ret != 0)
-                goto out;
-
-        ret = request_irq(dz_ports[0].port.irq, dz_interrupt, IRQF_DISABLED,
-                          "DZ", &dz_ports[0]);
-        if (ret != 0) {
-                printk(KERN_ERR "dz: Cannot get IRQ %d!\n",
-                       dz_ports[0].port.irq);
-                goto out_unregister;
-        }
+        if (ret)
+                return ret;
 
         for (i = 0; i < DZ_NB_PORT; i++)
-                uart_add_one_port(&dz_reg, &dz_ports[i].port);
-
-        return ret;
+                uart_add_one_port(&dz_reg, &dz_mux.dport[i].port);
 
-out_unregister:
-        uart_unregister_driver(&dz_reg);
-
-out:
-        return ret;
+        return 0;
 }
 
 module_init(dz_init);
-
-MODULE_DESCRIPTION("DECstation DZ serial driver");
-MODULE_LICENSE("GPL");