media: dvb_ca_en50221: Used a helper variable

Used a helper variable "struct dvb_ca_slot *sl" instead of
"ca->slot_info[slot]". This reduces the line length and simplifies
code reading.

Fixed also "-strict" checks in this patch:
- Comparison to NULL written as "!<var>".

Signed-off-by: Jasmin Jessich <jasmin@anw.at>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

diff --git a/drivers/media/dvb-core/dvb_ca_en50221.c b/drivers/media/dvb-core/dvb_ca_en50221.c
index d06cdc7..7207ff5 100644 (file)
--- a/drivers/media/dvb-core/dvb_ca_en50221.c
+++ b/drivers/media/dvb-core/dvb_ca_en50221.c
@@ -234,13 +234,14 @@ static char *findstr(char *haystack, int hlen, char *needle, int nlen)
  */
 static int dvb_ca_en50221_check_camstatus(struct dvb_ca_private *ca, int slot)
 {
+       struct dvb_ca_slot *sl = &ca->slot_info[slot];
        int slot_status;
        int cam_present_now;
        int cam_changed;
 
        /* IRQ mode */
        if (ca->flags & DVB_CA_EN50221_FLAG_IRQ_CAMCHANGE) {
-               return (atomic_read(&ca->slot_info[slot].camchange_count) != 0);
+               return (atomic_read(&sl->camchange_count) != 0);
        }
 
        /* poll mode */
@@ -249,22 +250,23 @@ static int dvb_ca_en50221_check_camstatus(struct dvb_ca_private *ca, int slot)
        cam_present_now = (slot_status & DVB_CA_EN50221_POLL_CAM_PRESENT) ? 1 : 0;
        cam_changed = (slot_status & DVB_CA_EN50221_POLL_CAM_CHANGED) ? 1 : 0;
        if (!cam_changed) {
-               int cam_present_old = (ca->slot_info[slot].slot_state != DVB_CA_SLOTSTATE_NONE);
+               int cam_present_old = (sl->slot_state != DVB_CA_SLOTSTATE_NONE);
+
                cam_changed = (cam_present_now != cam_present_old);
        }
 
        if (cam_changed) {
                if (!cam_present_now) {
-                       ca->slot_info[slot].camchange_type = DVB_CA_EN50221_CAMCHANGE_REMOVED;
+                       sl->camchange_type = DVB_CA_EN50221_CAMCHANGE_REMOVED;
                } else {
-                       ca->slot_info[slot].camchange_type = DVB_CA_EN50221_CAMCHANGE_INSERTED;
+                       sl->camchange_type = DVB_CA_EN50221_CAMCHANGE_INSERTED;
                }
-               atomic_set(&ca->slot_info[slot].camchange_count, 1);
+               atomic_set(&sl->camchange_count, 1);
        } else {
-               if ((ca->slot_info[slot].slot_state == DVB_CA_SLOTSTATE_WAITREADY) &&
+               if ((sl->slot_state == DVB_CA_SLOTSTATE_WAITREADY) &&
                    (slot_status & DVB_CA_EN50221_POLL_CAM_READY)) {
                        // move to validate state if reset is completed
-                       ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_VALIDATE;
+                       sl->slot_state = DVB_CA_SLOTSTATE_VALIDATE;
                }
        }
 
@@ -333,6 +335,7 @@ static int dvb_ca_en50221_wait_if_status(struct dvb_ca_private *ca, int slot,
  */
 static int dvb_ca_en50221_link_init(struct dvb_ca_private *ca, int slot)
 {
+       struct dvb_ca_slot *sl = &ca->slot_info[slot];
        int ret;
        int buf_size;
        u8 buf[2];
@@ -340,13 +343,13 @@ static int dvb_ca_en50221_link_init(struct dvb_ca_private *ca, int slot)
        dprintk("%s\n", __func__);
 
        /* we'll be determining these during this function */
-       ca->slot_info[slot].da_irq_supported = 0;
+       sl->da_irq_supported = 0;
 
        /*
         * set the host link buffer size temporarily. it will be overwritten
         * with the real negotiated size later.
         */
-       ca->slot_info[slot].link_buf_size = 2;
+       sl->link_buf_size = 2;
 
        /* read the buffer size from the CAM */
        ret = ca->pub->write_cam_control(ca->pub, slot, CTRLIF_COMMAND,
@@ -367,7 +370,7 @@ static int dvb_ca_en50221_link_init(struct dvb_ca_private *ca, int slot)
        buf_size = (buf[0] << 8) | buf[1];
        if (buf_size > HOST_LINK_BUF_SIZE)
                buf_size = HOST_LINK_BUF_SIZE;
-       ca->slot_info[slot].link_buf_size = buf_size;
+       sl->link_buf_size = buf_size;
        buf[0] = buf_size >> 8;
        buf[1] = buf_size & 0xff;
        dprintk("Chosen link buffer size of %i\n", buf_size);
@@ -459,6 +462,7 @@ static int dvb_ca_en50221_read_tuple(struct dvb_ca_private *ca, int slot,
  */
 static int dvb_ca_en50221_parse_attributes(struct dvb_ca_private *ca, int slot)
 {
+       struct dvb_ca_slot *sl;
        int address = 0;
        int tuple_length;
        int tuple_type;
@@ -531,10 +535,10 @@ static int dvb_ca_en50221_parse_attributes(struct dvb_ca_private *ca, int slot)
        rasz = tuple[0] & 3;
        if (tuple_length < (3 + rasz + 14))
                return -EINVAL;
-       ca->slot_info[slot].config_base = 0;
-       for (i = 0; i < rasz + 1; i++) {
-               ca->slot_info[slot].config_base |= (tuple[2 + i] << (8 * i));
-       }
+       sl = &ca->slot_info[slot];
+       sl->config_base = 0;
+       for (i = 0; i < rasz + 1; i++)
+               sl->config_base |= (tuple[2 + i] << (8 * i));
 
        /* check it contains the correct DVB string */
        dvb_str = findstr((char *)tuple, tuple_length, "DVB_CI_V", 8);
@@ -568,7 +572,7 @@ static int dvb_ca_en50221_parse_attributes(struct dvb_ca_private *ca, int slot)
                                break;
 
                        /* get the config option */
-                       ca->slot_info[slot].config_option = tuple[0] & 0x3f;
+                       sl->config_option = tuple[0] & 0x3f;
 
                        /* OK, check it contains the correct strings */
                        if (!findstr((char *)tuple, tuple_length,
@@ -598,8 +602,7 @@ static int dvb_ca_en50221_parse_attributes(struct dvb_ca_private *ca, int slot)
                return -EINVAL;
 
        dprintk("Valid DVB CAM detected MANID:%x DEVID:%x CONFIGBASE:0x%x CONFIGOPTION:0x%x\n",
-               manfid, devid, ca->slot_info[slot].config_base,
-               ca->slot_info[slot].config_option);
+               manfid, devid, sl->config_base, sl->config_option);
 
        // success!
        return 0;
@@ -614,19 +617,20 @@ static int dvb_ca_en50221_parse_attributes(struct dvb_ca_private *ca, int slot)
  */
 static int dvb_ca_en50221_set_configoption(struct dvb_ca_private *ca, int slot)
 {
+       struct dvb_ca_slot *sl = &ca->slot_info[slot];
        int configoption;
 
        dprintk("%s\n", __func__);
 
        /* set the config option */
-       ca->pub->write_attribute_mem(ca->pub, slot,
-                                    ca->slot_info[slot].config_base,
-                                    ca->slot_info[slot].config_option);
+       ca->pub->write_attribute_mem(ca->pub, slot, sl->config_base,
+                                    sl->config_option);
 
        /* check it */
-       configoption = ca->pub->read_attribute_mem(ca->pub, slot, ca->slot_info[slot].config_base);
+       configoption = ca->pub->read_attribute_mem(ca->pub, slot,
+                                                  sl->config_base);
        dprintk("Set configoption 0x%x, read configoption 0x%x\n",
-               ca->slot_info[slot].config_option, configoption & 0x3f);
+               sl->config_option, configoption & 0x3f);
 
        /* fine! */
        return 0;
@@ -651,6 +655,7 @@ static int dvb_ca_en50221_set_configoption(struct dvb_ca_private *ca, int slot)
 static int dvb_ca_en50221_read_data(struct dvb_ca_private *ca, int slot,
                                    u8 *ebuf, int ecount)
 {
+       struct dvb_ca_slot *sl = &ca->slot_info[slot];
        int bytes_read;
        int status;
        u8 buf[HOST_LINK_BUF_SIZE];
@@ -662,13 +667,13 @@ static int dvb_ca_en50221_read_data(struct dvb_ca_private *ca, int slot,
        if (ebuf == NULL) {
                int buf_free;
 
-               if (ca->slot_info[slot].rx_buffer.data == NULL) {
+               if (!sl->rx_buffer.data) {
                        status = -EIO;
                        goto exit;
                }
-               buf_free = dvb_ringbuffer_free(&ca->slot_info[slot].rx_buffer);
+               buf_free = dvb_ringbuffer_free(&sl->rx_buffer);
 
-               if (buf_free < (ca->slot_info[slot].link_buf_size +
+               if (buf_free < (sl->link_buf_size +
                                DVB_RINGBUFFER_PKTHDRSIZE)) {
                        status = -EAGAIN;
                        goto exit;
@@ -676,7 +681,7 @@ static int dvb_ca_en50221_read_data(struct dvb_ca_private *ca, int slot,
        }
 
        if (ca->pub->read_data &&
-           (ca->slot_info[slot].slot_state != DVB_CA_SLOTSTATE_LINKINIT)) {
+           (sl->slot_state != DVB_CA_SLOTSTATE_LINKINIT)) {
                if (ebuf == NULL)
                        status = ca->pub->read_data(ca->pub, slot, buf,
                                                    sizeof(buf));
@@ -714,20 +719,18 @@ static int dvb_ca_en50221_read_data(struct dvb_ca_private *ca, int slot,
 
                /* check it will fit */
                if (ebuf == NULL) {
-                       if (bytes_read > ca->slot_info[slot].link_buf_size) {
+                       if (bytes_read > sl->link_buf_size) {
                                pr_err("dvb_ca adapter %d: CAM tried to send a buffer larger than the link buffer size (%i > %i)!\n",
                                       ca->dvbdev->adapter->num, bytes_read,
-                                      ca->slot_info[slot].link_buf_size);
-                               ca->slot_info[slot].slot_state =
-                                                    DVB_CA_SLOTSTATE_LINKINIT;
+                                      sl->link_buf_size);
+                               sl->slot_state = DVB_CA_SLOTSTATE_LINKINIT;
                                status = -EIO;
                                goto exit;
                        }
                        if (bytes_read < 2) {
                                pr_err("dvb_ca adapter %d: CAM sent a buffer that was less than 2 bytes!\n",
                                       ca->dvbdev->adapter->num);
-                               ca->slot_info[slot].slot_state =
-                                                    DVB_CA_SLOTSTATE_LINKINIT;
+                               sl->slot_state = DVB_CA_SLOTSTATE_LINKINIT;
                                status = -EIO;
                                goto exit;
                        }
@@ -758,8 +761,7 @@ static int dvb_ca_en50221_read_data(struct dvb_ca_private *ca, int slot,
                if (status < 0)
                        goto exit;
                if (status & STATUSREG_RE) {
-                       ca->slot_info[slot].slot_state =
-                                                    DVB_CA_SLOTSTATE_LINKINIT;
+                       sl->slot_state = DVB_CA_SLOTSTATE_LINKINIT;
                        status = -EIO;
                        goto exit;
                }
@@ -767,11 +769,11 @@ static int dvb_ca_en50221_read_data(struct dvb_ca_private *ca, int slot,
 
        /* OK, add it to the receive buffer, or copy into external buffer if supplied */
        if (ebuf == NULL) {
-               if (ca->slot_info[slot].rx_buffer.data == NULL) {
+               if (!sl->rx_buffer.data) {
                        status = -EIO;
                        goto exit;
                }
-               dvb_ringbuffer_pkt_write(&ca->slot_info[slot].rx_buffer, buf, bytes_read);
+               dvb_ringbuffer_pkt_write(&sl->rx_buffer, buf, bytes_read);
        } else {
                memcpy(ebuf, buf, bytes_read);
        }
@@ -805,6 +807,7 @@ exit:
 static int dvb_ca_en50221_write_data(struct dvb_ca_private *ca, int slot,
                                     u8 *buf, int bytes_write)
 {
+       struct dvb_ca_slot *sl = &ca->slot_info[slot];
        int status;
        int i;
 
@@ -812,11 +815,11 @@ static int dvb_ca_en50221_write_data(struct dvb_ca_private *ca, int slot,
 
 
        /* sanity check */
-       if (bytes_write > ca->slot_info[slot].link_buf_size)
+       if (bytes_write > sl->link_buf_size)
                return -EINVAL;
 
        if (ca->pub->write_data &&
-           (ca->slot_info[slot].slot_state != DVB_CA_SLOTSTATE_LINKINIT))
+           (sl->slot_state != DVB_CA_SLOTSTATE_LINKINIT))
                return ca->pub->write_data(ca->pub, slot, buf, bytes_write);
 
        /*
@@ -898,7 +901,7 @@ static int dvb_ca_en50221_write_data(struct dvb_ca_private *ca, int slot,
        if (status < 0)
                goto exit;
        if (status & STATUSREG_WE) {
-               ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_LINKINIT;
+               sl->slot_state = DVB_CA_SLOTSTATE_LINKINIT;
                status = -EIO;
                goto exit;
        }
@@ -956,6 +959,7 @@ static int dvb_ca_en50221_slot_shutdown(struct dvb_ca_private *ca, int slot)
 void dvb_ca_en50221_camchange_irq(struct dvb_ca_en50221 *pubca, int slot, int change_type)
 {
        struct dvb_ca_private *ca = pubca->private;
+       struct dvb_ca_slot *sl = &ca->slot_info[slot];
 
        dprintk("CAMCHANGE IRQ slot:%i change_type:%i\n", slot, change_type);
 
@@ -968,8 +972,8 @@ void dvb_ca_en50221_camchange_irq(struct dvb_ca_en50221 *pubca, int slot, int ch
                return;
        }
 
-       ca->slot_info[slot].camchange_type = change_type;
-       atomic_inc(&ca->slot_info[slot].camchange_count);
+       sl->camchange_type = change_type;
+       atomic_inc(&sl->camchange_count);
        dvb_ca_en50221_thread_wakeup(ca);
 }
 EXPORT_SYMBOL(dvb_ca_en50221_camchange_irq);
@@ -984,11 +988,12 @@ EXPORT_SYMBOL(dvb_ca_en50221_camchange_irq);
 void dvb_ca_en50221_camready_irq(struct dvb_ca_en50221 *pubca, int slot)
 {
        struct dvb_ca_private *ca = pubca->private;
+       struct dvb_ca_slot *sl = &ca->slot_info[slot];
 
        dprintk("CAMREADY IRQ slot:%i\n", slot);
 
-       if (ca->slot_info[slot].slot_state == DVB_CA_SLOTSTATE_WAITREADY) {
-               ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_VALIDATE;
+       if (sl->slot_state == DVB_CA_SLOTSTATE_WAITREADY) {
+               sl->slot_state = DVB_CA_SLOTSTATE_VALIDATE;
                dvb_ca_en50221_thread_wakeup(ca);
        }
 }
@@ -1004,16 +1009,17 @@ EXPORT_SYMBOL(dvb_ca_en50221_camready_irq);
 void dvb_ca_en50221_frda_irq(struct dvb_ca_en50221 *pubca, int slot)
 {
        struct dvb_ca_private *ca = pubca->private;
+       struct dvb_ca_slot *sl = &ca->slot_info[slot];
        int flags;
 
        dprintk("FR/DA IRQ slot:%i\n", slot);
 
-       switch (ca->slot_info[slot].slot_state) {
+       switch (sl->slot_state) {
        case DVB_CA_SLOTSTATE_LINKINIT:
                flags = ca->pub->read_cam_control(pubca, slot, CTRLIF_STATUS);
                if (flags & STATUSREG_DA) {
                        dprintk("CAM supports DA IRQ\n");
-                       ca->slot_info[slot].da_irq_supported = 1;
+                       sl->da_irq_supported = 1;
                }
                break;
 
@@ -1059,7 +1065,9 @@ static void dvb_ca_en50221_thread_update_delay(struct dvb_ca_private *ca)
         * call might take several hundred milliseconds until timeout!
         */
        for (slot = 0; slot < ca->slot_count; slot++) {
-               switch (ca->slot_info[slot].slot_state) {
+               struct dvb_ca_slot *sl = &ca->slot_info[slot];
+
+               switch (sl->slot_state) {
                default:
                case DVB_CA_SLOTSTATE_NONE:
                        delay = HZ * 60;  /* 60s */
@@ -1085,7 +1093,7 @@ static void dvb_ca_en50221_thread_update_delay(struct dvb_ca_private *ca)
                        if (!(ca->flags & DVB_CA_EN50221_FLAG_IRQ_CAMCHANGE))
                                delay = HZ / 10;  /* 100ms */
                        if (ca->open) {
-                               if ((!ca->slot_info[slot].da_irq_supported) ||
+                               if ((!sl->da_irq_supported) ||
                                    (!(ca->flags & DVB_CA_EN50221_FLAG_IRQ_DA)))
                                        delay = HZ / 10;  /* 100ms */
                        }
@@ -1374,15 +1382,17 @@ static int dvb_ca_en50221_io_do_ioctl(struct file *file,
        switch (cmd) {
        case CA_RESET:
                for (slot = 0; slot < ca->slot_count; slot++) {
-                       mutex_lock(&ca->slot_info[slot].slot_lock);
-                       if (ca->slot_info[slot].slot_state != DVB_CA_SLOTSTATE_NONE) {
+                       struct dvb_ca_slot *sl = &ca->slot_info[slot];
+
+                       mutex_lock(&sl->slot_lock);
+                       if (sl->slot_state != DVB_CA_SLOTSTATE_NONE) {
                                dvb_ca_en50221_slot_shutdown(ca, slot);
                                if (ca->flags & DVB_CA_EN50221_FLAG_IRQ_CAMCHANGE)
                                        dvb_ca_en50221_camchange_irq(ca->pub,
                                                                     slot,
                                                                     DVB_CA_EN50221_CAMCHANGE_INSERTED);
                        }
-                       mutex_unlock(&ca->slot_info[slot].slot_lock);
+                       mutex_unlock(&sl->slot_lock);
                }
                ca->next_read_slot = 0;
                dvb_ca_en50221_thread_wakeup(ca);
@@ -1400,21 +1410,23 @@ static int dvb_ca_en50221_io_do_ioctl(struct file *file,
 
        case CA_GET_SLOT_INFO: {
                struct ca_slot_info *info = parg;
+               struct dvb_ca_slot *sl;
 
-               if ((info->num > ca->slot_count) || (info->num < 0)) {
+               slot = info->num;
+               if ((slot > ca->slot_count) || (slot < 0)) {
                        err = -EINVAL;
                        goto out_unlock;
                }
 
                info->type = CA_CI_LINK;
                info->flags = 0;
-               if ((ca->slot_info[info->num].slot_state != DVB_CA_SLOTSTATE_NONE)
-                       && (ca->slot_info[info->num].slot_state != DVB_CA_SLOTSTATE_INVALID)) {
+               sl = &ca->slot_info[slot];
+               if ((sl->slot_state != DVB_CA_SLOTSTATE_NONE) &&
+                   (sl->slot_state != DVB_CA_SLOTSTATE_INVALID)) {
                        info->flags = CA_CI_MODULE_PRESENT;
                }
-               if (ca->slot_info[info->num].slot_state == DVB_CA_SLOTSTATE_RUNNING) {
+               if (sl->slot_state == DVB_CA_SLOTSTATE_RUNNING)
                        info->flags |= CA_CI_MODULE_READY;
-               }
                break;
        }
 
@@ -1462,6 +1474,7 @@ static ssize_t dvb_ca_en50221_io_write(struct file *file,
 {
        struct dvb_device *dvbdev = file->private_data;
        struct dvb_ca_private *ca = dvbdev->priv;
+       struct dvb_ca_slot *sl;
        u8 slot, connection_id;
        int status;
        u8 fragbuf[HOST_LINK_BUF_SIZE];
@@ -1483,14 +1496,15 @@ static ssize_t dvb_ca_en50221_io_write(struct file *file,
                return -EFAULT;
        buf += 2;
        count -= 2;
+       sl = &ca->slot_info[slot];
 
        /* check if the slot is actually running */
-       if (ca->slot_info[slot].slot_state != DVB_CA_SLOTSTATE_RUNNING)
+       if (sl->slot_state != DVB_CA_SLOTSTATE_RUNNING)
                return -EINVAL;
 
        /* fragment the packets & store in the buffer */
        while (fragpos < count) {
-               fraglen = ca->slot_info[slot].link_buf_size - 2;
+               fraglen = sl->link_buf_size - 2;
                if (fraglen < 0)
                        break;
                if (fraglen > HOST_LINK_BUF_SIZE - 2)
@@ -1510,14 +1524,14 @@ static ssize_t dvb_ca_en50221_io_write(struct file *file,
                written = 0;
                while (!time_after(jiffies, timeout)) {
                        /* check the CAM hasn't been removed/reset in the meantime */
-                       if (ca->slot_info[slot].slot_state != DVB_CA_SLOTSTATE_RUNNING) {
+                       if (sl->slot_state != DVB_CA_SLOTSTATE_RUNNING) {
                                status = -EIO;
                                goto exit;
                        }
 
-                       mutex_lock(&ca->slot_info[slot].slot_lock);
+                       mutex_lock(&sl->slot_lock);
                        status = dvb_ca_en50221_write_data(ca, slot, fragbuf, fraglen + 2);
-                       mutex_unlock(&ca->slot_info[slot].slot_lock);
+                       mutex_unlock(&sl->slot_lock);
                        if (status == (fraglen + 2)) {
                                written = 1;
                                break;
@@ -1557,16 +1571,17 @@ static int dvb_ca_en50221_io_read_condition(struct dvb_ca_private *ca,
 
        slot = ca->next_read_slot;
        while ((slot_count < ca->slot_count) && (!found)) {
-               if (ca->slot_info[slot].slot_state != DVB_CA_SLOTSTATE_RUNNING)
+               struct dvb_ca_slot *sl = &ca->slot_info[slot];
+
+               if (sl->slot_state != DVB_CA_SLOTSTATE_RUNNING)
                        goto nextslot;
 
-               if (ca->slot_info[slot].rx_buffer.data == NULL) {
+               if (!sl->rx_buffer.data)
                        return 0;
-               }
 
-               idx = dvb_ringbuffer_pkt_next(&ca->slot_info[slot].rx_buffer, -1, &fraglen);
+               idx = dvb_ringbuffer_pkt_next(&sl->rx_buffer, -1, &fraglen);
                while (idx != -1) {
-                       dvb_ringbuffer_pkt_read(&ca->slot_info[slot].rx_buffer, idx, 0, hdr, 2);
+                       dvb_ringbuffer_pkt_read(&sl->rx_buffer, idx, 0, hdr, 2);
                        if (connection_id == -1)
                                connection_id = hdr[0];
                        if ((hdr[0] == connection_id) && ((hdr[1] & 0x80) == 0)) {
@@ -1575,7 +1590,8 @@ static int dvb_ca_en50221_io_read_condition(struct dvb_ca_private *ca,
                                break;
                        }
 
-                       idx = dvb_ringbuffer_pkt_next(&ca->slot_info[slot].rx_buffer, idx, &fraglen);
+                       idx = dvb_ringbuffer_pkt_next(&sl->rx_buffer, idx,
+                                                     &fraglen);
                }
 
 nextslot:
@@ -1603,6 +1619,7 @@ static ssize_t dvb_ca_en50221_io_read(struct file *file, char __user *buf,
 {
        struct dvb_device *dvbdev = file->private_data;
        struct dvb_ca_private *ca = dvbdev->priv;
+       struct dvb_ca_slot *sl;
        int status;
        int result = 0;
        u8 hdr[2];
@@ -1639,7 +1656,8 @@ static ssize_t dvb_ca_en50221_io_read(struct file *file, char __user *buf,
                return status;
        }
 
-       idx = dvb_ringbuffer_pkt_next(&ca->slot_info[slot].rx_buffer, -1, &fraglen);
+       sl = &ca->slot_info[slot];
+       idx = dvb_ringbuffer_pkt_next(&sl->rx_buffer, -1, &fraglen);
        pktlen = 2;
        do {
                if (idx == -1) {
@@ -1649,7 +1667,7 @@ static ssize_t dvb_ca_en50221_io_read(struct file *file, char __user *buf,
                        goto exit;
                }
 
-               dvb_ringbuffer_pkt_read(&ca->slot_info[slot].rx_buffer, idx, 0, hdr, 2);
+               dvb_ringbuffer_pkt_read(&sl->rx_buffer, idx, 0, hdr, 2);
                if (connection_id == -1)
                        connection_id = hdr[0];
                if (hdr[0] == connection_id) {
@@ -1660,10 +1678,14 @@ static ssize_t dvb_ca_en50221_io_read(struct file *file, char __user *buf,
                                        fraglen -= 2;
                                }
 
-                               if ((status = dvb_ringbuffer_pkt_read_user(&ca->slot_info[slot].rx_buffer, idx, 2,
-                                                                     buf + pktlen, fraglen)) < 0) {
+                               status =
+                                  dvb_ringbuffer_pkt_read_user(&sl->rx_buffer,
+                                                               idx, 2,
+                                                               buf + pktlen,
+                                                               fraglen);
+                               if (status < 0)
                                        goto exit;
-                               }
+
                                pktlen += fraglen;
                        }
 
@@ -1672,9 +1694,9 @@ static ssize_t dvb_ca_en50221_io_read(struct file *file, char __user *buf,
                        dispose = 1;
                }
 
-               idx2 = dvb_ringbuffer_pkt_next(&ca->slot_info[slot].rx_buffer, idx, &fraglen);
+               idx2 = dvb_ringbuffer_pkt_next(&sl->rx_buffer, idx, &fraglen);
                if (dispose)
-                       dvb_ringbuffer_pkt_dispose(&ca->slot_info[slot].rx_buffer, idx);
+                       dvb_ringbuffer_pkt_dispose(&sl->rx_buffer, idx);
                idx = idx2;
                dispose = 0;
        } while (!last_fragment);
@@ -1720,15 +1742,16 @@ static int dvb_ca_en50221_io_open(struct inode *inode, struct file *file)
        }
 
        for (i = 0; i < ca->slot_count; i++) {
+               struct dvb_ca_slot *sl = &ca->slot_info[i];
 
-               if (ca->slot_info[i].slot_state == DVB_CA_SLOTSTATE_RUNNING) {
-                       if (ca->slot_info[i].rx_buffer.data != NULL) {
+               if (sl->slot_state == DVB_CA_SLOTSTATE_RUNNING) {
+                       if (!sl->rx_buffer.data) {
                                /*
                                 * it is safe to call this here without locks
                                 * because ca->open == 0. Data is not read in
                                 * this case
                                 */
-                               dvb_ringbuffer_flush(&ca->slot_info[i].rx_buffer);
+                               dvb_ringbuffer_flush(&sl->rx_buffer);
                        }
                }
        }
@@ -1888,11 +1911,13 @@ int dvb_ca_en50221_init(struct dvb_adapter *dvb_adapter,
 
        /* now initialise each slot */
        for (i = 0; i < slot_count; i++) {
-               memset(&ca->slot_info[i], 0, sizeof(struct dvb_ca_slot));
-               ca->slot_info[i].slot_state = DVB_CA_SLOTSTATE_NONE;
-               atomic_set(&ca->slot_info[i].camchange_count, 0);
-               ca->slot_info[i].camchange_type = DVB_CA_EN50221_CAMCHANGE_REMOVED;
-               mutex_init(&ca->slot_info[i].slot_lock);
+               struct dvb_ca_slot *sl = &ca->slot_info[i];
+
+               memset(sl, 0, sizeof(struct dvb_ca_slot));
+               sl->slot_state = DVB_CA_SLOTSTATE_NONE;
+               atomic_set(&sl->camchange_count, 0);
+               sl->camchange_type = DVB_CA_EN50221_CAMCHANGE_REMOVED;
+               mutex_init(&sl->slot_lock);
        }
 
        mutex_init(&ca->ioctl_mutex);