openwrt-xburst/package/nozomi/patches/002-nozomi_vf_01.patch

--- a/nozomi.c
+++ b/nozomi.c
@@ -7,6 +7,9 @@
  *
  * Maintained by: Paul Hardwick, p.hardwick@option.com
  *
+ * Patches:
+ *          Locking code changes for Vodafone, Andrew Bird & Phil Sanderson
+ *
  * Source has been ported from an implementation made by Filip Aben, f.aben@option.com
  *
  * --------------------------------------------------------------------------
@@ -61,6 +64,7 @@
 #include <linux/interrupt.h>
 #include <linux/kmod.h>
 #include <linux/proc_fs.h>
+#include <linux/init.h>
 #include <asm/uaccess.h>
 
 
@@ -133,23 +137,23 @@ static int nzdebug = NOZOMI_DEBUG_LEVEL;
 /* TODO: rewrite to optimize macros... */
 #define SET_FCR(value__) \
   do {  \
-	writew((value__), (void*) (dc->REG_FCR )); \
+	writew((value__), (dc->REG_FCR )); \
 } while(0)
 
 #define SET_IER(value__, mask__) \
   do {  \
 	dc->ier_last_written = (dc->ier_last_written & ~mask__) | (value__ & mask__ );\
-    writew( dc->ier_last_written, (void*) (dc->REG_IER));\
+    writew( dc->ier_last_written, (dc->REG_IER));\
 } while(0)
 
 #define GET_IER(read_val__) \
   do {  \
-	(read_val__) = readw((void*) (dc->REG_IER));\
+	(read_val__) = readw((dc->REG_IER));\
 } while(0)
 
 #define GET_IIR(read_val__) \
   do {  \
-	(read_val__) = readw((void*) (dc->REG_IIR));\
+	(read_val__) = readw( (dc->REG_IIR));\
 } while(0)
 
 #define GET_MEM(value__, addr__, length__) \
@@ -265,7 +269,7 @@ static int nzdebug = NOZOMI_DEBUG_LEVEL;
 /* There are two types of nozomi cards, one with 2048 memory and with 8192 memory */
 typedef enum {
 	F32_2 = 2048, /* Has 512 bytes downlink and uplink * 2             -> 2048 */
-	F32_8 = 9192, /* Has 3072 bytes downlink and 1024 bytes uplink * 2 -> 8192 */
+	F32_8 = 8192, /* Has 3072 bytes downlink and 1024 bytes uplink * 2 -> 8192 */
 } card_type_t;
 
 /* Two different toggle channels exist */
@@ -438,12 +442,12 @@ typedef struct {
 	u32				     base_addr;
 	u8				     closing;
 
-	/* Register addresses */
-	u32				     REG_IIR;
-	u32				     REG_FCR;
-	u32				     REG_IER;
+   /* Pointers to registers ( register is tagged volatile, not pointer ) */
+	volatile u16 * REG_IIR;
+	volatile u16 * REG_FCR;
+	volatile u16 * REG_IER;
 
-	volatile u16		 ier_last_written;
+	u16		 ier_last_written;
 	card_type_t 	     card_type;
 	config_table_t 	     config_table; /* Configuration table */
 	struct pci_dev 	    *pdev;
@@ -490,7 +494,7 @@ static struct pci_device_id nozomi_pci_t
 
 /* Used to store interrupt variables */
 typedef struct {
-	volatile u16 read_iir; /* Holds current interrupt tokens */
+	u16 read_iir; /* Holds current interrupt tokens */
 } irq_t;
 
 MODULE_DEVICE_TABLE(pci, nozomi_pci_tbl);
@@ -1345,9 +1349,9 @@ void nozomi_setup_private_data(dc_t *dc)
 	u32 offset = dc->base_addr + dc->card_type/2;
 	int i;
 
-	dc->REG_FCR = offset + R_FCR;
-	dc->REG_IIR = offset + R_IIR;
-	dc->REG_IER = offset + R_IER;
+	dc->REG_FCR = (u16 *) (offset + R_FCR);
+	dc->REG_IIR = (u16 *) (offset + R_IIR);
+	dc->REG_IER = (u16 *) (offset + R_IER);
 	dc->ier_last_written = 0;
 	dc->closing = 0;
 
@@ -1366,13 +1370,16 @@ void nozomi_setup_private_data(dc_t *dc)
 static void tty_flip_queue_function(void *tmp_dc) {
 	dc_t *dc = (dc_t*) tmp_dc;
 	int i;
+   u32 flags;
 
 	/* Enable interrupt for that port */
 	for(i=0;i<MAX_PORT;i++) {
 		if (dc->port[i].tty_dont_flip) {
 			D6("Enable for port: %d", i);
 			dc->port[i].tty_dont_flip = 0;
+         spin_lock_irqsave(&dc->spin_mutex, flags);
 			enable_transmit_dl(dc->port[i].tty_index, dc);
+         spin_unlock_irqrestore(&dc->spin_mutex, flags);
 		}
 	}
 }
@@ -1555,7 +1562,11 @@ err_disable_device:
 
 static void tty_do_close(dc_t *dc, port_t *port) {
 
-	down(&port->tty_sem);
+	u32      flags;
+
+	if(down_interruptible(&port->tty_sem)){
+      return;
+   }
 
 	if ( !port->tty_open_count ) {
 		goto exit;
@@ -1569,7 +1580,9 @@ static void tty_do_close(dc_t *dc, port_
 
 	if ( port->tty_open_count == 0) {
         D1("close: %d", port->token_dl );
+      spin_lock_irqsave(&dc->spin_mutex, flags);
 		SET_IER( 0,  port->token_dl );
+      spin_unlock_irqrestore(&dc->spin_mutex, flags);
 	}
 
 exit:
@@ -1679,8 +1692,11 @@ static int ntty_open(struct tty_struct *
 	s32 index = get_index(tty);
 	port_t *port = get_port_by_tty(tty);
 	dc_t *dc = get_dc_by_tty(tty);
+	u32      flags;
 
-	down(&port->tty_sem);
+   if(down_interruptible(&port->tty_sem)){
+      return -ERESTARTSYS;
+   }
 
 	tty->low_latency  = 1;
 	tty->driver_data  = port;
@@ -1698,7 +1714,9 @@ static int ntty_open(struct tty_struct *
 	if ( port->tty_open_count == 1) {
 		port->rx_data = port->tx_data = 0;
         D1("open: %d", port->token_dl );
+      spin_lock_irqsave(&dc->spin_mutex, flags);
 		SET_IER( port->token_dl,  port->token_dl );
+      spin_unlock_irqrestore(&dc->spin_mutex, flags);
 	}
 
 	up(&port->tty_sem);
@@ -1722,6 +1740,7 @@ static s32 ntty_write(struct tty_struct 
 	int                  rval = -EINVAL;
 	dc_t                *dc = get_dc_by_tty(tty);
 	port_t              *port = (port_t *) tty->driver_data;
+	u32      flags;
 
 	/* D1( "WRITEx: %d, index = %d", count, index); */
 
@@ -1729,7 +1748,10 @@ static s32 ntty_write(struct tty_struct 
 		return -ENODEV;
 	}
 
-	down(&port->tty_sem);
+   if(down_trylock(&port->tty_sem) ) { // must test lock as tty layer wraps calls to this function with BKL
+      ERR("Would have deadlocked - return ERESTARTSYS");
+      return -ERESTARTSYS;
+   }
 
 	if (! port->tty_open_count) {
         D1( " ");
@@ -1752,6 +1774,7 @@ static s32 ntty_write(struct tty_struct 
 		goto exit;
 	}
 
+   spin_lock_irqsave(&dc->spin_mutex, flags);
 	// CTS is only valid on the modem channel
 	if ( port == &(dc->port[PORT_MDM]) ) {
 		if ( port->ctrl_dl.CTS ) {
@@ -1763,6 +1786,7 @@ static s32 ntty_write(struct tty_struct 
 	} else {
 		enable_transmit_ul(port->tty_index, dc );
 	}
+   spin_unlock_irqrestore(&dc->spin_mutex, flags);
 
 exit:
 	up(&port->tty_sem);
@@ -1782,7 +1806,9 @@ static int ntty_write_room(struct tty_st
         return 0;
 	}
 
-	down(&port->tty_sem);
+   if(down_interruptible(&port->tty_sem)){
+      return 0;
+   }
 
 	if (! port->tty_open_count) {
 		goto exit;
@@ -1969,6 +1995,8 @@ static int ntty_ioctl_tiocgicount(struct
 
 static int ntty_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg) {
 	port_t *port = (port_t *) tty->driver_data;
+	dc_t    *dc = get_dc_by_tty(tty);
+	u32      flags;
 	int mask;
 	int rval = -ENOIOCTLCMD;
 
@@ -1991,7 +2019,9 @@ static int ntty_ioctl(struct tty_struct 
 		rval =  ntty_ioctl_tiocgicount(tty, file, cmd, arg);
 		break;
 	case TIOCMGET:
+      spin_lock_irqsave(&dc->spin_mutex, flags);
 		rval = ntty_tiocmget(tty, file);
+      spin_unlock_irqrestore(&dc->spin_mutex, flags);
 		break;
 	case TIOCMSET:
 		rval = ntty_tiocmset(tty, file, arg);
@@ -2000,20 +2030,24 @@ static int ntty_ioctl(struct tty_struct 
 		if (get_user(mask, (unsigned long *) arg))
 			return -EFAULT;
 
+      spin_lock_irqsave(&dc->spin_mutex, flags);
 		if (mask & TIOCM_RTS)
 			set_rts(port->tty_index, 0);
 		if (mask & TIOCM_DTR)
 			set_dtr(port->tty_index, 0);
+      spin_unlock_irqrestore(&dc->spin_mutex, flags);
 		rval = 0;
 		break;
    	case TIOCMBIS:
 		if (get_user(mask, (unsigned long *) arg))
 			return -EFAULT;
 
+      spin_lock_irqsave(&dc->spin_mutex, flags);
 		if (mask & TIOCM_RTS)
 			set_rts(port->tty_index, 1);
 		if (mask & TIOCM_DTR)
 			set_dtr(port->tty_index, 1);
+      spin_unlock_irqrestore(&dc->spin_mutex, flags);
 		rval = 0;
 		break;
 	case TCFLSH: