Staging: ipack/devices/ipoctal: split ipoctal_channel from ipoctal.

By moving everything channel related into a separate struct we will be
able to clean up a lot of code.  In the end tty->driver_data will no
longer need to point to ipoctal but instead can point to the respective
channel.

Signed-off-by: Jens Taprogge <jens.taprogge@taprogge.org>
Signed-off-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 150 insertions, 136 deletions

diff --git a/drivers/staging/ipack/devices/ipoctal.c b/drivers/staging/ipack/devices/ipoctal.c
index 35513d9e013a..9ab0e8082565 100644
--- a/drivers/staging/ipack/devices/ipoctal.c
+++ b/drivers/staging/ipack/devices/ipoctal.c
@@ -30,22 +30,26 @@
 
 static const struct tty_operations ipoctal_fops;
 
+struct ipoctal_channel {
+        struct ipoctal_stats            stats;
+        unsigned int                    nb_bytes;
+        unsigned int                    count_wr;
+        wait_queue_head_t               queue;
+        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;
+};
+
 struct ipoctal {
         struct list_head                list;
         struct ipack_device             *dev;
         unsigned int                    board_id;
-        union scc2698_channel __iomem   *chan_regs;
-        union scc2698_block __iomem     *block_regs;
-        struct ipoctal_stats            chan_stats[NR_CHANNELS];
-        unsigned int                    nb_bytes[NR_CHANNELS];
-        unsigned int                    count_wr[NR_CHANNELS];
-        wait_queue_head_t               queue[NR_CHANNELS];
-        spinlock_t                      lock[NR_CHANNELS];
-        unsigned int                    pointer_read[NR_CHANNELS];
-        unsigned int                    pointer_write[NR_CHANNELS];
-        atomic_t                        open[NR_CHANNELS];
+        struct ipoctal_channel          channel[NR_CHANNELS];
         unsigned char                   write;
-        struct tty_port                 tty_port[NR_CHANNELS];
         struct tty_driver               *tty_drv;
 };
 
@@ -87,7 +91,7 @@ static struct ipoctal *ipoctal_find_board(struct tty_struct *tty)
 static int ipoctal_port_activate(struct tty_port *port, struct tty_struct *tty)
 {
         struct ipoctal *ipoctal;
-        int channel = tty->index;
+        struct ipoctal_channel *channel;
 
         ipoctal = ipoctal_find_board(tty);
 
@@ -96,17 +100,18 @@ static int ipoctal_port_activate(struct tty_port *port, struct tty_struct *tty)
                         tty->driver->major);
                 return -ENODEV;
         }
+        channel = &ipoctal->channel[tty->index];
 
-        ipoctal_write_io_reg(ipoctal, &ipoctal->chan_regs[channel].w.cr,
+        ipoctal_write_io_reg(ipoctal, &channel->regs->w.cr,
                              CR_ENABLE_RX);
         return 0;
 }
 
 static int ipoctal_open(struct tty_struct *tty, struct file *file)
 {
-        int channel = tty->index;
         int res;
         struct ipoctal *ipoctal;
+        struct ipoctal_channel *channel;
 
         ipoctal = ipoctal_find_board(tty);
 
@@ -115,17 +120,18 @@ static int ipoctal_open(struct tty_struct *tty, struct file *file)
                         tty->driver->major);
                 return -ENODEV;
         }
+        channel = &ipoctal->channel[tty->index];
 
-        if (atomic_read(&ipoctal->open[channel]))
+        if (atomic_read(&channel->open))
                 return -EBUSY;
 
         tty->driver_data = ipoctal;
 
-        res = tty_port_open(&ipoctal->tty_port[channel], tty, file);
+        res = tty_port_open(&channel->tty_port, tty, file);
         if (res)
                 return res;
 
-        atomic_inc(&ipoctal->open[channel]);
+        atomic_inc(&channel->open);
         return 0;
 }
 
@@ -141,26 +147,27 @@ static void ipoctal_reset_stats(struct ipoctal_stats *stats)
 
 static void ipoctal_free_channel(struct tty_struct *tty)
 {
-        int channel = tty->index;
         struct ipoctal *ipoctal = tty->driver_data;
+        struct ipoctal_channel *channel;
 
         if (ipoctal == NULL)
                 return;
+        channel = &ipoctal->channel[tty->index];
 
-        ipoctal_reset_stats(&ipoctal->chan_stats[channel]);
-        ipoctal->pointer_read[channel] = 0;
-        ipoctal->pointer_write[channel] = 0;
-        ipoctal->nb_bytes[channel] = 0;
+        ipoctal_reset_stats(&channel->stats);
+        channel->pointer_read = 0;
+        channel->pointer_write = 0;
+        channel->nb_bytes = 0;
 }
 
 static void ipoctal_close(struct tty_struct *tty, struct file *filp)
 {
-        int channel = tty->index;
         struct ipoctal *ipoctal = tty->driver_data;
+        struct ipoctal_channel *channel = &ipoctal->channel[tty->index];
 
-        tty_port_close(&ipoctal->tty_port[channel], tty, filp);
+        tty_port_close(&channel->tty_port, tty, filp);
 
-        if (atomic_dec_and_test(&ipoctal->open[channel]))
+        if (atomic_dec_and_test(&channel->open))
                 ipoctal_free_channel(tty);
 }
 
@@ -168,24 +175,23 @@ static int ipoctal_get_icount(struct tty_struct *tty,
                               struct serial_icounter_struct *icount)
 {
         struct ipoctal *ipoctal = tty->driver_data;
-        int channel = tty->index;
+        struct ipoctal_channel *channel = &ipoctal->channel[tty->index];
 
         icount->cts = 0;
         icount->dsr = 0;
         icount->rng = 0;
         icount->dcd = 0;
-        icount->rx = ipoctal->chan_stats[channel].rx;
-        icount->tx = ipoctal->chan_stats[channel].tx;
-        icount->frame = ipoctal->chan_stats[channel].framing_err;
-        icount->parity = ipoctal->chan_stats[channel].parity_err;
-        icount->brk = ipoctal->chan_stats[channel].rcv_break;
+        icount->rx = channel->stats.rx;
+        icount->tx = channel->stats.tx;
+        icount->frame = channel->stats.framing_err;
+        icount->parity = channel->stats.parity_err;
+        icount->brk = channel->stats.rcv_break;
         return 0;
 }
 
 static int ipoctal_irq_handler(void *arg)
 {
-        unsigned int channel;
-        unsigned int block;
+        unsigned int ichannel;
         unsigned char isr;
         unsigned char sr;
         unsigned char isr_tx_rdy, isr_rx_rdy;
@@ -193,14 +199,16 @@ static int ipoctal_irq_handler(void *arg)
         unsigned char flag;
         struct tty_struct *tty;
         struct ipoctal *ipoctal = (struct ipoctal *) arg;
+        struct ipoctal_channel *channel;
 
         /* Check all channels */
-        for (channel = 0; channel < NR_CHANNELS; channel++) {
+        for (ichannel = 0; ichannel < NR_CHANNELS; ichannel++) {
+                channel = &ipoctal->channel[ichannel];
                 /* If there is no client, skip the check */
-                if (!atomic_read(&ipoctal->open[channel]))
+                if (!atomic_read(&channel->open))
                         continue;
 
-                tty = tty_port_tty_get(&ipoctal->tty_port[channel]);
+                tty = tty_port_tty_get(&channel->tty_port);
                 if (!tty)
                         continue;
 
@@ -208,13 +216,12 @@ static int ipoctal_irq_handler(void *arg)
                  * The HW is organized in pair of channels.
                  * See which register we need to read from
                  */
-                block = channel / 2;
                 isr = ipoctal_read_io_reg(ipoctal,
-                                          &ipoctal->block_regs[block].r.isr);
+                                          &channel->block_regs->r.isr);
                 sr = ipoctal_read_io_reg(ipoctal,
-                                         &ipoctal->chan_regs[channel].r.sr);
+                                         &channel->regs->r.sr);
 
-                if ((channel % 2) == 1) {
+                if ((ichannel % 2) == 1) {
                         isr_tx_rdy = isr & ISR_TxRDY_B;
                         isr_rx_rdy = isr & ISR_RxRDY_FFULL_B;
                 } else {
@@ -227,47 +234,47 @@ static int ipoctal_irq_handler(void *arg)
                  */
                 if ((ipoctal->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) &&
                     (sr & SR_TX_EMPTY) &&
-                    (ipoctal->nb_bytes[channel] == 0)) {
+                    (channel->nb_bytes == 0)) {
                         ipoctal_write_io_reg(ipoctal,
-                                             &ipoctal->chan_regs[channel].w.cr,
+                                             &channel->regs->w.cr,
                                              CR_DISABLE_TX);
                         ipoctal_write_cr_cmd(ipoctal,
-                                             &ipoctal->chan_regs[channel].w.cr,
+                                             &channel->regs->w.cr,
                                              CR_CMD_NEGATE_RTSN);
                         ipoctal_write_io_reg(ipoctal,
-                                             &ipoctal->chan_regs[channel].w.cr,
+                                             &channel->regs->w.cr,
                                              CR_ENABLE_RX);
                         ipoctal->write = 1;
-                        wake_up_interruptible(&ipoctal->queue[channel]);
+                        wake_up_interruptible(&channel->queue);
                 }
 
                 /* RX data */
                 if (isr_rx_rdy && (sr & SR_RX_READY)) {
                         value = ipoctal_read_io_reg(ipoctal,
-                                                    &ipoctal->chan_regs[channel].r.rhr);
+                                                    &channel->regs->r.rhr);
                         flag = TTY_NORMAL;
 
                         /* Error: count statistics */
                         if (sr & SR_ERROR) {
                                 ipoctal_write_cr_cmd(ipoctal,
-                                                     &ipoctal->chan_regs[channel].w.cr,
+                                                     &channel->regs->w.cr,
                                                      CR_CMD_RESET_ERR_STATUS);
 
                                 if (sr & SR_OVERRUN_ERROR) {
-                                        ipoctal->chan_stats[channel].overrun_err++;
+                                        channel->stats.overrun_err++;
                                         /* Overrun doesn't affect the current character*/
                                         tty_insert_flip_char(tty, 0, TTY_OVERRUN);
                                 }
                                 if (sr & SR_PARITY_ERROR) {
-                                        ipoctal->chan_stats[channel].parity_err++;
+                                        channel->stats.parity_err++;
                                         flag = TTY_PARITY;
                                 }
                                 if (sr & SR_FRAMING_ERROR) {
-                                        ipoctal->chan_stats[channel].framing_err++;
+                                        channel->stats.framing_err++;
                                         flag = TTY_FRAME;
                                 }
                                 if (sr & SR_RECEIVED_BREAK) {
-                                        ipoctal->chan_stats[channel].rcv_break++;
+                                        channel->stats.rcv_break++;
                                         flag = TTY_BREAK;
                                 }
                         }
@@ -277,30 +284,29 @@ static int ipoctal_irq_handler(void *arg)
 
                 /* TX of each character */
                 if (isr_tx_rdy && (sr & SR_TX_READY)) {
-                        unsigned int *pointer_write =
-                                &ipoctal->pointer_write[channel];
+                        unsigned int *pointer_write = &channel->pointer_write;
 
-                        if (ipoctal->nb_bytes[channel] <= 0) {
-                                ipoctal->nb_bytes[channel] = 0;
+                        if (channel->nb_bytes <= 0) {
+                                channel->nb_bytes = 0;
                                 continue;
                         }
 
-                        value = ipoctal->tty_port[channel].xmit_buf[*pointer_write];
+                        value = channel->tty_port.xmit_buf[*pointer_write];
                         ipoctal_write_io_reg(ipoctal,
-                                             &ipoctal->chan_regs[channel].w.thr,
+                                             &channel->regs->w.thr,
                                              value);
-                        ipoctal->chan_stats[channel].tx++;
-                        ipoctal->count_wr[channel]++;
+                        channel->stats.tx++;
+                        channel->count_wr++;
                         (*pointer_write)++;
                         *pointer_write = *pointer_write % PAGE_SIZE;
-                        ipoctal->nb_bytes[channel]--;
+                        channel->nb_bytes--;
 
-                        if ((ipoctal->nb_bytes[channel] == 0) &&
-                            (waitqueue_active(&ipoctal->queue[channel]))) {
+                        if ((channel->nb_bytes == 0) &&
+                            (waitqueue_active(&channel->queue))) {
 
                                 if (ipoctal->board_id != IPACK1_DEVICE_ID_SBS_OCTAL_485) {
                                         ipoctal->write = 1;
-                                        wake_up_interruptible(&ipoctal->queue[channel]);
+                                        wake_up_interruptible(&channel->queue);
                                 }
                         }
                 }
@@ -348,6 +354,9 @@ static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr,
         struct tty_driver *tty;
         char name[20];
         unsigned char board_id;
+        struct ipoctal_channel *channel;
+        union scc2698_channel __iomem *chan_regs;
+        union scc2698_block __iomem *block_regs;
 
         res = ipoctal->dev->bus->ops->map_space(ipoctal->dev, 0,
                                                 IPACK_ID_SPACE);
@@ -385,41 +394,45 @@ static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr,
         }
 
         /* Save the virtual address to access the registers easily */
-        ipoctal->chan_regs =
+        chan_regs =
                 (union scc2698_channel __iomem *) ipoctal->dev->io_space.address;
-        ipoctal->block_regs =
+        block_regs =
                 (union scc2698_block __iomem *) ipoctal->dev->io_space.address;
 
         /* Disable RX and TX before touching anything */
         for (i = 0; i < NR_CHANNELS ; i++) {
-                ipoctal_write_io_reg(ipoctal, &ipoctal->chan_regs[i].w.cr,
+                struct ipoctal_channel *channel = &ipoctal->channel[i];
+                channel->regs = chan_regs + i;
+                channel->block_regs = block_regs + (i >> 1);
+
+                ipoctal_write_io_reg(ipoctal, &channel->regs->w.cr,
                                      CR_DISABLE_RX | CR_DISABLE_TX);
-                ipoctal_write_cr_cmd(ipoctal, &ipoctal->chan_regs[i].w.cr,
+                ipoctal_write_cr_cmd(ipoctal, &channel->regs->w.cr,
                                      CR_CMD_RESET_RX);
-                ipoctal_write_cr_cmd(ipoctal, &ipoctal->chan_regs[i].w.cr,
+                ipoctal_write_cr_cmd(ipoctal, &channel->regs->w.cr,
                                      CR_CMD_RESET_TX);
                 ipoctal_write_io_reg(ipoctal,
-                                     &ipoctal->chan_regs[i].w.mr,
+                                     &channel->regs->w.mr,
                                      MR1_CHRL_8_BITS | MR1_ERROR_CHAR |
                                      MR1_RxINT_RxRDY); /* mr1 */
                 ipoctal_write_io_reg(ipoctal,
-                                     &ipoctal->chan_regs[i].w.mr,
+                                     &channel->regs->w.mr,
                                      0); /* mr2 */
                 ipoctal_write_io_reg(ipoctal,
-                                     &ipoctal->chan_regs[i].w.csr,
+                                     &channel->regs->w.csr,
                                      TX_CLK_9600  | RX_CLK_9600);
         }
 
         for (i = 0; i < IP_OCTAL_NB_BLOCKS; i++) {
                 ipoctal_write_io_reg(ipoctal,
-                                     &ipoctal->block_regs[i].w.acr,
+                                     &block_regs[i].w.acr,
                                      ACR_BRG_SET2);
                 ipoctal_write_io_reg(ipoctal,
-                                     &ipoctal->block_regs[i].w.opcr,
+                                     &block_regs[i].w.opcr,
                                      OPCR_MPP_OUTPUT | OPCR_MPOa_RTSN |
                                      OPCR_MPOb_RTSN);
                 ipoctal_write_io_reg(ipoctal,
-                                     &ipoctal->block_regs[i].w.imr,
+                                     &block_regs[i].w.imr,
                                      IMR_TxRDY_A | IMR_RxRDY_FFULL_A |
                                      IMR_DELTA_BREAK_A | IMR_TxRDY_B |
                                      IMR_RxRDY_FFULL_B | IMR_DELTA_BREAK_B);
@@ -472,25 +485,26 @@ static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr,
         ipoctal->tty_drv = tty;
 
         for (i = 0; i < NR_CHANNELS; i++) {
-                tty_port_init(&ipoctal->tty_port[i]);
-                tty_port_alloc_xmit_buf(&ipoctal->tty_port[i]);
-                ipoctal->tty_port[i].ops = &ipoctal_tty_port_ops;
-
-                ipoctal_reset_stats(&ipoctal->chan_stats[i]);
-                ipoctal->nb_bytes[i] = 0;
-                init_waitqueue_head(&ipoctal->queue[i]);
-
-                spin_lock_init(&ipoctal->lock[i]);
-                ipoctal->pointer_read[i] = 0;
-                ipoctal->pointer_write[i] = 0;
-                ipoctal->nb_bytes[i] = 0;
+                channel = &ipoctal->channel[i];
+                tty_port_init(&channel->tty_port);
+                tty_port_alloc_xmit_buf(&channel->tty_port);
+                channel->tty_port.ops = &ipoctal_tty_port_ops;
+
+                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;
+                channel->nb_bytes = 0;
                 tty_register_device(tty, i, NULL);
 
                 /*
                  * Enable again the RX. TX will be enabled when
                  * there is something to send
                  */
-                ipoctal_write_io_reg(ipoctal, &ipoctal->chan_regs[i].w.cr,
+                ipoctal_write_io_reg(ipoctal, &channel->regs->w.cr,
                                      CR_ENABLE_RX);
         }
 
@@ -505,23 +519,22 @@ out_unregister_id_space:
         return res;
 }
 
-static inline int ipoctal_copy_write_buffer(struct ipoctal *ipoctal,
-                                            unsigned int channel,
+static inline int ipoctal_copy_write_buffer(struct ipoctal_channel *channel,
                                             const unsigned char *buf,
                                             int count)
 {
         unsigned long flags;
         int i;
-        unsigned int *pointer_read = &ipoctal->pointer_read[channel];
+        unsigned int *pointer_read = &channel->pointer_read;
 
         /* Copy the bytes from the user buffer to the internal one */
         for (i = 0; i < count; i++) {
-                if (i <= (PAGE_SIZE - ipoctal->nb_bytes[channel])) {
-                        spin_lock_irqsave(&ipoctal->lock[channel], flags);
-                        ipoctal->tty_port[channel].xmit_buf[*pointer_read] = buf[i];
+                if (i <= (PAGE_SIZE - channel->nb_bytes)) {
+                        spin_lock_irqsave(&channel->lock, flags);
+                        channel->tty_port.xmit_buf[*pointer_read] = buf[i];
                         *pointer_read = (*pointer_read + 1) % PAGE_SIZE;
-                        ipoctal->nb_bytes[channel]++;
-                        spin_unlock_irqrestore(&ipoctal->lock[channel], flags);
+                        channel->nb_bytes++;
+                        spin_unlock_irqrestore(&channel->lock, flags);
                 } else {
                         break;
                 }
@@ -529,21 +542,22 @@ static inline int ipoctal_copy_write_buffer(struct ipoctal *ipoctal,
         return i;
 }
 
-static int ipoctal_write(struct ipoctal *ipoctal, unsigned int channel,
+static int ipoctal_write(struct ipoctal *ipoctal, unsigned int ichannel,
                          const unsigned char *buf, int count)
 {
-        ipoctal->nb_bytes[channel] = 0;
-        ipoctal->count_wr[channel] = 0;
+        struct ipoctal_channel *channel = &ipoctal->channel[ichannel];
+        channel->nb_bytes = 0;
+        channel->count_wr = 0;
 
-        ipoctal_copy_write_buffer(ipoctal, channel, buf, count);
+        ipoctal_copy_write_buffer(channel, buf, count);
 
         /* As the IP-OCTAL 485 only supports half duplex, do it manually */
         if (ipoctal->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) {
                 ipoctal_write_io_reg(ipoctal,
-                                     &ipoctal->chan_regs[channel].w.cr,
+                                     &channel->regs->w.cr,
                                      CR_DISABLE_RX);
                 ipoctal_write_cr_cmd(ipoctal,
-                                     &ipoctal->chan_regs[channel].w.cr,
+                                     &channel->regs->w.cr,
                                      CR_CMD_ASSERT_RTSN);
         }
 
@@ -552,40 +566,39 @@ static int ipoctal_write(struct ipoctal *ipoctal, unsigned int channel,
          * operations
          */
         ipoctal_write_io_reg(ipoctal,
-                             &ipoctal->chan_regs[channel].w.cr,
+                             &channel->regs->w.cr,
                              CR_ENABLE_TX);
-        wait_event_interruptible(ipoctal->queue[channel], ipoctal->write);
+        wait_event_interruptible(channel->queue, ipoctal->write);
         ipoctal_write_io_reg(ipoctal,
-                             &ipoctal->chan_regs[channel].w.cr,
+                             &channel->regs->w.cr,
                              CR_DISABLE_TX);
 
         ipoctal->write = 0;
-        return ipoctal->count_wr[channel];
+        return channel->count_wr;
 }
 
 static int ipoctal_write_tty(struct tty_struct *tty,
                              const unsigned char *buf, int count)
 {
-        unsigned int channel = tty->index;
         struct ipoctal *ipoctal = tty->driver_data;
 
-        return ipoctal_write(ipoctal, channel, buf, count);
+        return ipoctal_write(ipoctal, tty->index, buf, count);
 }
 
 static int ipoctal_write_room(struct tty_struct *tty)
 {
-        int channel = tty->index;
         struct ipoctal *ipoctal = tty->driver_data;
+        struct ipoctal_channel *channel = &ipoctal->channel[tty->index];
 
-        return PAGE_SIZE - ipoctal->nb_bytes[channel];
+        return PAGE_SIZE - channel->nb_bytes;
 }
 
 static int ipoctal_chars_in_buffer(struct tty_struct *tty)
 {
-        int channel = tty->index;
         struct ipoctal *ipoctal = tty->driver_data;
+        struct ipoctal_channel *channel = &ipoctal->channel[tty->index];
 
-        return ipoctal->nb_bytes[channel];
+        return channel->nb_bytes;
 }
 
 static void ipoctal_set_termios(struct tty_struct *tty,
@@ -595,22 +608,22 @@ static void ipoctal_set_termios(struct tty_struct *tty,
         unsigned char mr1 = 0;
         unsigned char mr2 = 0;
         unsigned char csr = 0;
-        unsigned int channel = tty->index;
         struct ipoctal *ipoctal = tty->driver_data;
+        struct ipoctal_channel *channel = &ipoctal->channel[tty->index];
         speed_t baud;
 
         cflag = tty->termios->c_cflag;
 
         /* Disable and reset everything before change the setup */
-        ipoctal_write_io_reg(ipoctal, &ipoctal->chan_regs[channel].w.cr,
+        ipoctal_write_io_reg(ipoctal, &channel->regs->w.cr,
                              CR_DISABLE_RX | CR_DISABLE_TX);
-        ipoctal_write_cr_cmd(ipoctal, &ipoctal->chan_regs[channel].w.cr,
+        ipoctal_write_cr_cmd(ipoctal, &channel->regs->w.cr,
                              CR_CMD_RESET_RX);
-        ipoctal_write_cr_cmd(ipoctal, &ipoctal->chan_regs[channel].w.cr,
+        ipoctal_write_cr_cmd(ipoctal, &channel->regs->w.cr,
                              CR_CMD_RESET_TX);
-        ipoctal_write_cr_cmd(ipoctal, &ipoctal->chan_regs[channel].w.cr,
+        ipoctal_write_cr_cmd(ipoctal, &channel->regs->w.cr,
                              CR_CMD_RESET_ERR_STATUS);
-        ipoctal_write_cr_cmd(ipoctal, &ipoctal->chan_regs[channel].w.cr,
+        ipoctal_write_cr_cmd(ipoctal, &channel->regs->w.cr,
                              CR_CMD_RESET_MR);
 
         /* Set Bits per chars */
@@ -724,45 +737,45 @@ static void ipoctal_set_termios(struct tty_struct *tty,
         mr1 |= MR1_RxINT_RxRDY;
 
         /* Write the control registers */
-        ipoctal_write_io_reg(ipoctal, &ipoctal->chan_regs[channel].w.mr, mr1);
-        ipoctal_write_io_reg(ipoctal, &ipoctal->chan_regs[channel].w.mr, mr2);
-        ipoctal_write_io_reg(ipoctal, &ipoctal->chan_regs[channel].w.csr, csr);
+        ipoctal_write_io_reg(ipoctal, &channel->regs->w.mr, mr1);
+        ipoctal_write_io_reg(ipoctal, &channel->regs->w.mr, mr2);
+        ipoctal_write_io_reg(ipoctal, &channel->regs->w.csr, csr);
 
         /* Enable again the RX */
-        ipoctal_write_io_reg(ipoctal, &ipoctal->chan_regs[channel].w.cr,
+        ipoctal_write_io_reg(ipoctal, &channel->regs->w.cr,
                              CR_ENABLE_RX);
 }
 
 static void ipoctal_hangup(struct tty_struct *tty)
 {
         unsigned long flags;
-        int channel = tty->index;
         struct ipoctal *ipoctal = tty->driver_data;
+        struct ipoctal_channel *channel = &ipoctal->channel[tty->index];
 
         if (ipoctal == NULL)
                 return;
 
-        spin_lock_irqsave(&ipoctal->lock[channel], flags);
-        ipoctal->nb_bytes[channel] = 0;
-        ipoctal->pointer_read[channel] = 0;
-        ipoctal->pointer_write[channel] = 0;
-        spin_unlock_irqrestore(&ipoctal->lock[channel], flags);
+        spin_lock_irqsave(&channel->lock, flags);
+        channel->nb_bytes = 0;
+        channel->pointer_read = 0;
+        channel->pointer_write = 0;
+        spin_unlock_irqrestore(&channel->lock, flags);
 
-        tty_port_hangup(&ipoctal->tty_port[channel]);
+        tty_port_hangup(&channel->tty_port);
 
-        ipoctal_write_io_reg(ipoctal, &ipoctal->chan_regs[channel].w.cr,
+        ipoctal_write_io_reg(ipoctal, &channel->regs->w.cr,
                              CR_DISABLE_RX | CR_DISABLE_TX);
-        ipoctal_write_cr_cmd(ipoctal, &ipoctal->chan_regs[channel].w.cr,
+        ipoctal_write_cr_cmd(ipoctal, &channel->regs->w.cr,
                              CR_CMD_RESET_RX);
-        ipoctal_write_cr_cmd(ipoctal, &ipoctal->chan_regs[channel].w.cr,
+        ipoctal_write_cr_cmd(ipoctal, &channel->regs->w.cr,
                              CR_CMD_RESET_TX);
-        ipoctal_write_cr_cmd(ipoctal, &ipoctal->chan_regs[channel].w.cr,
+        ipoctal_write_cr_cmd(ipoctal, &channel->regs->w.cr,
                              CR_CMD_RESET_ERR_STATUS);
-        ipoctal_write_cr_cmd(ipoctal, &ipoctal->chan_regs[channel].w.cr,
+        ipoctal_write_cr_cmd(ipoctal, &channel->regs->w.cr,
                              CR_CMD_RESET_MR);
 
-        clear_bit(ASYNCB_INITIALIZED, &ipoctal->tty_port[channel].flags);
-        wake_up_interruptible(&ipoctal->tty_port[channel].open_wait);
+        clear_bit(ASYNCB_INITIALIZED, &channel->tty_port.flags);
+        wake_up_interruptible(&channel->tty_port.open_wait);
 }
 
 static const struct tty_operations ipoctal_fops = {
@@ -806,8 +819,9 @@ static void __ipoctal_remove(struct ipoctal *ipoctal)
         ipoctal->dev->bus->ops->free_irq(ipoctal->dev);
 
         for (i = 0; i < NR_CHANNELS; i++) {
+                struct ipoctal_channel *channel = &ipoctal->channel[i];
                 tty_unregister_device(ipoctal->tty_drv, i);
-                tty_port_free_xmit_buf(&ipoctal->tty_port[i]);
+                tty_port_free_xmit_buf(&channel->tty_port);
         }
 
         tty_unregister_driver(ipoctal->tty_drv);