1 files changed, 49 insertions, 64 deletions

diff --git a/drivers/ipack/devices/ipoctal.c b/drivers/ipack/devices/ipoctal.c
index ab20a0851dd2..141094e7c06e 100644
--- a/drivers/ipack/devices/ipoctal.c
+++ b/drivers/ipack/devices/ipoctal.c
@@ -20,7 +20,6 @@
 #include <linux/serial.h>
 #include <linux/tty_flip.h>
 #include <linux/slab.h>
-#include <linux/atomic.h>
 #include <linux/io.h>
 #include <linux/ipack.h>
 #include "ipoctal.h"
@@ -38,21 +37,19 @@ struct ipoctal_channel {
         spinlock_t                      lock;
         unsigned int                    pointer_read;
         unsigned int                    pointer_write;
-        atomic_t                        open;
         struct tty_port                 tty_port;
         union scc2698_channel __iomem   *regs;
         union scc2698_block __iomem     *block_regs;
         unsigned int                    board_id;
-        unsigned char                   *board_write;
         u8                              isr_rx_rdy_mask;
         u8                              isr_tx_rdy_mask;
+        unsigned int                    rx_enable;
 };
 
 struct ipoctal {
         struct ipack_device             *dev;
         unsigned int                    board_id;
         struct ipoctal_channel          channel[NR_CHANNELS];
-        unsigned char                   write;
         struct tty_driver               *tty_drv;
         u8 __iomem                      *mem8_space;
         u8 __iomem                      *int_space;
@@ -64,28 +61,23 @@ static int ipoctal_port_activate(struct tty_port *port, struct tty_struct *tty)
 
         channel = dev_get_drvdata(tty->dev);
 
+        /*
+         * Enable RX. TX will be enabled when
+         * there is something to send
+         */
         iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
+        channel->rx_enable = 1;
         return 0;
 }
 
 static int ipoctal_open(struct tty_struct *tty, struct file *file)
 {
-        int res;
         struct ipoctal_channel *channel;
 
         channel = dev_get_drvdata(tty->dev);
-
-        if (atomic_read(&channel->open))
-                return -EBUSY;
-
         tty->driver_data = channel;
 
-        res = tty_port_open(&channel->tty_port, tty, file);
-        if (res)
-                return res;
-
-        atomic_inc(&channel->open);
-        return 0;
+        return tty_port_open(&channel->tty_port, tty, file);
 }
 
 static void ipoctal_reset_stats(struct ipoctal_stats *stats)
@@ -111,9 +103,7 @@ static void ipoctal_close(struct tty_struct *tty, struct file *filp)
         struct ipoctal_channel *channel = tty->driver_data;
 
         tty_port_close(&channel->tty_port, tty, filp);
-
-        if (atomic_dec_and_test(&channel->open))
-                ipoctal_free_channel(channel);
+        ipoctal_free_channel(channel);
 }
 
 static int ipoctal_get_icount(struct tty_struct *tty,
@@ -137,11 +127,12 @@ static void ipoctal_irq_rx(struct ipoctal_channel *channel, u8 sr)
 {
         struct tty_port *port = &channel->tty_port;
         unsigned char value;
-        unsigned char flag = TTY_NORMAL;
+        unsigned char flag;
         u8 isr;
 
         do {
                 value = ioread8(&channel->regs->r.rhr);
+                flag = TTY_NORMAL;
                 /* Error: count statistics */
                 if (sr & SR_ERROR) {
                         iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr);
@@ -183,10 +174,8 @@ static void ipoctal_irq_tx(struct ipoctal_channel *channel)
         unsigned char value;
         unsigned int *pointer_write = &channel->pointer_write;
 
-        if (channel->nb_bytes <= 0) {
-                channel->nb_bytes = 0;
+        if (channel->nb_bytes == 0)
                 return;
-        }
 
         value = channel->tty_port.xmit_buf[*pointer_write];
         iowrite8(value, &channel->regs->w.thr);
@@ -194,39 +183,27 @@ static void ipoctal_irq_tx(struct ipoctal_channel *channel)
         (*pointer_write)++;
         *pointer_write = *pointer_write % PAGE_SIZE;
         channel->nb_bytes--;
-
-        if ((channel->nb_bytes == 0) &&
-            (waitqueue_active(&channel->queue))) {
-
-                if (channel->board_id != IPACK1_DEVICE_ID_SBS_OCTAL_485) {
-                        *channel->board_write = 1;
-                        wake_up_interruptible(&channel->queue);
-                }
-        }
 }
 
 static void ipoctal_irq_channel(struct ipoctal_channel *channel)
 {
         u8 isr, sr;
 
-        /* If there is no client, skip the check */
-        if (!atomic_read(&channel->open))
-                return;
-
+        spin_lock(&channel->lock);
         /* The HW is organized in pair of channels.  See which register we need
          * to read from */
         isr = ioread8(&channel->block_regs->r.isr);
         sr = ioread8(&channel->regs->r.sr);
 
-        /* In case of RS-485, change from TX to RX when finishing TX.
-         * Half-duplex. */
-        if ((channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) &&
-            (sr & SR_TX_EMPTY) && (channel->nb_bytes == 0)) {
+        if ((sr & SR_TX_EMPTY) && (channel->nb_bytes == 0)) {
                 iowrite8(CR_DISABLE_TX, &channel->regs->w.cr);
-                iowrite8(CR_CMD_NEGATE_RTSN, &channel->regs->w.cr);
-                iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
-                *channel->board_write = 1;
-                wake_up_interruptible(&channel->queue);
+                /* In case of RS-485, change from TX to RX when finishing TX.
+                 * Half-duplex. */
+                if (channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) {
+                        iowrite8(CR_CMD_NEGATE_RTSN, &channel->regs->w.cr);
+                        iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
+                        channel->rx_enable = 1;
+                }
         }
 
         /* RX data */
@@ -237,7 +214,7 @@ static void ipoctal_irq_channel(struct ipoctal_channel *channel)
         if ((isr & channel->isr_tx_rdy_mask) && (sr & SR_TX_READY))
                 ipoctal_irq_tx(channel);
 
-        tty_flip_buffer_push(&channel->tty_port);
+        spin_unlock(&channel->lock);
 }
 
 static irqreturn_t ipoctal_irq_handler(void *arg)
@@ -245,14 +222,14 @@ static irqreturn_t ipoctal_irq_handler(void *arg)
         unsigned int i;
         struct ipoctal *ipoctal = (struct ipoctal *) arg;
 
-        /* Check all channels */
-        for (i = 0; i < NR_CHANNELS; i++)
-                ipoctal_irq_channel(&ipoctal->channel[i]);
-
         /* Clear the IPack device interrupt */
         readw(ipoctal->int_space + ACK_INT_REQ0);
         readw(ipoctal->int_space + ACK_INT_REQ1);
 
+        /* Check all channels */
+        for (i = 0; i < NR_CHANNELS; i++)
+                ipoctal_irq_channel(&ipoctal->channel[i]);
+
         return IRQ_HANDLED;
 }
 
@@ -306,7 +283,7 @@ static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr,
         ipoctal->mem8_space =
                 devm_ioremap_nocache(&ipoctal->dev->dev,
                                      region->start, 0x8000);
-        if (!addr) {
+        if (!ipoctal->mem8_space) {
                 dev_err(&ipoctal->dev->dev,
                         "Unable to map slot [%d:%d] MEM8 space!\n",
                         bus_nr, slot);
@@ -319,7 +296,6 @@ static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr,
                 struct ipoctal_channel *channel = &ipoctal->channel[i];
                 channel->regs = chan_regs + i;
                 channel->block_regs = block_regs + (i >> 1);
-                channel->board_write = &ipoctal->write;
                 channel->board_id = ipoctal->board_id;
                 if (i & 1) {
                         channel->isr_tx_rdy_mask = ISR_TxRDY_B;
@@ -330,6 +306,7 @@ static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr,
                 }
 
                 iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr);
+                channel->rx_enable = 0;
                 iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr);
                 iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr);
                 iowrite8(MR1_CHRL_8_BITS | MR1_ERROR_CHAR | MR1_RxINT_RxRDY,
@@ -402,8 +379,6 @@ static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr,
 
                 ipoctal_reset_stats(&channel->stats);
                 channel->nb_bytes = 0;
-                init_waitqueue_head(&channel->queue);
-
                 spin_lock_init(&channel->lock);
                 channel->pointer_read = 0;
                 channel->pointer_write = 0;
@@ -414,12 +389,6 @@ static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr,
                         continue;
                 }
                 dev_set_drvdata(tty_dev, channel);
-
-                /*
-                 * Enable again the RX. TX will be enabled when
-                 * there is something to send
-                 */
-                iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
         }
 
         return 0;
@@ -459,6 +428,7 @@ static int ipoctal_write_tty(struct tty_struct *tty,
         /* As the IP-OCTAL 485 only supports half duplex, do it manually */
         if (channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) {
                 iowrite8(CR_DISABLE_RX, &channel->regs->w.cr);
+                channel->rx_enable = 0;
                 iowrite8(CR_CMD_ASSERT_RTSN, &channel->regs->w.cr);
         }
 
@@ -467,10 +437,6 @@ static int ipoctal_write_tty(struct tty_struct *tty,
          * operations
          */
         iowrite8(CR_ENABLE_TX, &channel->regs->w.cr);
-        wait_event_interruptible(channel->queue, *channel->board_write);
-        iowrite8(CR_DISABLE_TX, &channel->regs->w.cr);
-
-        *channel->board_write = 0;
         return char_copied;
 }
 
@@ -622,8 +588,9 @@ static void ipoctal_set_termios(struct tty_struct *tty,
         iowrite8(mr2, &channel->regs->w.mr);
         iowrite8(csr, &channel->regs->w.csr);
 
-        /* Enable again the RX */
-        iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
+        /* Enable again the RX, if it was before */
+        if (channel->rx_enable)
+                iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
 }
 
 static void ipoctal_hangup(struct tty_struct *tty)
@@ -643,6 +610,7 @@ static void ipoctal_hangup(struct tty_struct *tty)
         tty_port_hangup(&channel->tty_port);
 
         iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr);
+        channel->rx_enable = 0;
         iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr);
         iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr);
         iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr);
@@ -652,6 +620,22 @@ static void ipoctal_hangup(struct tty_struct *tty)
         wake_up_interruptible(&channel->tty_port.open_wait);
 }
 
+static void ipoctal_shutdown(struct tty_struct *tty)
+{
+        struct ipoctal_channel *channel = tty->driver_data;
+
+        if (channel == NULL)
+                return;
+
+        iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr);
+        channel->rx_enable = 0;
+        iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr);
+        iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr);
+        iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr);
+        iowrite8(CR_CMD_RESET_MR, &channel->regs->w.cr);
+        clear_bit(ASYNCB_INITIALIZED, &channel->tty_port.flags);
+}
+
 static const struct tty_operations ipoctal_fops = {
         .ioctl =                NULL,
         .open =                 ipoctal_open,
@@ -662,6 +646,7 @@ static const struct tty_operations ipoctal_fops = {
         .chars_in_buffer =      ipoctal_chars_in_buffer,
         .get_icount =           ipoctal_get_icount,
         .hangup =               ipoctal_hangup,
+        .shutdown =             ipoctal_shutdown,
 };
 
 static int ipoctal_probe(struct ipack_device *dev)