1 files changed, 212 insertions, 132 deletions

diff --git a/drivers/staging/lirc/lirc_zilog.c b/drivers/staging/lirc/lirc_zilog.c
index 00f2e7d3b3e5..f2e8c63fa5bd 100644
--- a/drivers/staging/lirc/lirc_zilog.c
+++ b/drivers/staging/lirc/lirc_zilog.c
@@ -94,11 +94,13 @@ struct IR {
         struct mutex ir_lock;
         int open;
 
+        struct i2c_adapter *adapter;
         struct IR_rx *rx;
         struct IR_tx *tx;
 };
 
 /* Minor -> data mapping */
+static struct mutex ir_devices_lock;
 static struct IR *ir_devices[MAX_IRCTL_DEVICES];
 
 /* Block size for IR transmitter */
@@ -131,10 +133,11 @@ static struct mutex tx_data_lock;
 #define zilog_notify(s, args...) printk(KERN_NOTICE KBUILD_MODNAME ": " s, \
                                         ## args)
 #define zilog_error(s, args...) printk(KERN_ERR KBUILD_MODNAME ": " s, ## args)
+#define zilog_info(s, args...) printk(KERN_INFO KBUILD_MODNAME ": " s, ## args)
 
 /* module parameters */
 static int debug;       /* debug output */
-static int disable_rx;  /* disable RX device */
+static int tx_only;     /* only handle the IR Tx function */
 static int minor = -1;  /* minor number */
 
 #define dprintk(fmt, args...)                                           \
@@ -252,9 +255,6 @@ static int lirc_thread(void *arg)
         struct IR *ir = arg;
         struct IR_rx *rx = ir->rx;
 
-        if (rx == NULL)
-                return -ENXIO;
-
         if (rx->t_notify != NULL)
                 complete(rx->t_notify);
 
@@ -296,6 +296,7 @@ static int lirc_thread(void *arg)
                 complete(rx->t_notify);
 
         dprintk("poll thread ended\n");
+        /* FIXME - investigate if this is the proper way to shutdown a kthread*/
         return 0;
 }
 
@@ -1058,6 +1059,15 @@ static long ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
         return result;
 }
 
+/* ir_devices_lock must be held */
+static struct IR *find_ir_device_by_minor(unsigned int minor)
+{
+        if (minor >= MAX_IRCTL_DEVICES)
+                return NULL;
+
+        return ir_devices[minor];
+}
+
 /*
  * Open the IR device.  Get hold of our IR structure and
  * stash it in private_data for the file
@@ -1066,15 +1076,15 @@ static int open(struct inode *node, struct file *filep)
 {
         struct IR *ir;
         int ret;
+        unsigned int minor = MINOR(node->i_rdev);
 
         /* find our IR struct */
-        unsigned minor = MINOR(node->i_rdev);
-        if (minor >= MAX_IRCTL_DEVICES) {
-                dprintk("minor %d: open result = -ENODEV\n",
-                        minor);
+        mutex_lock(&ir_devices_lock);
+        ir = find_ir_device_by_minor(minor);
+        mutex_unlock(&ir_devices_lock);
+
+        if (ir == NULL)
                 return -ENODEV;
-        }
-        ir = ir_devices[minor];
 
         /* increment in use count */
         mutex_lock(&ir->ir_lock);
@@ -1159,136 +1169,203 @@ static const struct file_operations lirc_fops = {
         .release        = close
 };
 
-static int ir_remove(struct i2c_client *client)
+/* FIXME - investigate if this is the proper way to shutdown a kthread */
+static void destroy_rx_kthread(struct IR_rx *rx)
 {
-        struct IR *ir = i2c_get_clientdata(client);
-        struct IR_rx *rx = ir->rx;
-        struct IR_tx *tx = ir->tx;
+        DECLARE_COMPLETION(tn);
+        DECLARE_COMPLETION(tn2);
 
-        /* FIXME make tx, rx senitive */
-        mutex_lock(&ir->ir_lock);
+        if (rx == NULL)
+                return;
+
+        /* end up polling thread */
+        if (rx->task && !IS_ERR(rx->task)) {
+                rx->t_notify = &tn;
+                rx->t_notify2 = &tn2;
+                rx->shutdown = 1;
+                wake_up_process(rx->task);
+                complete(&tn2);
+                wait_for_completion(&tn);
+                rx->t_notify = NULL;
+                rx->t_notify2 = NULL;
+        }
+}
 
-        if (rx != NULL || tx != NULL) {
-                DECLARE_COMPLETION(tn);
-                DECLARE_COMPLETION(tn2);
-
-                /* end up polling thread */
-                if (rx->task && !IS_ERR(rx->task)) {
-                        rx->t_notify = &tn;
-                        rx->t_notify2 = &tn2;
-                        rx->shutdown = 1;
-                        wake_up_process(rx->task);
-                        complete(&tn2);
-                        wait_for_completion(&tn);
-                        rx->t_notify = NULL;
-                        rx->t_notify2 = NULL;
+/* ir_devices_lock must be held */
+static int add_ir_device(struct IR *ir)
+{
+        int i;
+
+        for (i = 0; i < MAX_IRCTL_DEVICES; i++)
+                if (ir_devices[i] == NULL) {
+                        ir_devices[i] = ir;
+                        break;
                 }
 
-        } else {
-                mutex_unlock(&ir->ir_lock);
-                zilog_error("%s: detached from something we didn't "
-                            "attach to\n", __func__);
-                return -ENODEV;
+        return i == MAX_IRCTL_DEVICES ? -ENOMEM : i;
+}
+
+/* ir_devices_lock must be held */
+static void del_ir_device(struct IR *ir)
+{
+        int i;
+
+        for (i = 0; i < MAX_IRCTL_DEVICES; i++)
+                if (ir_devices[i] == ir) {
+                        ir_devices[i] = NULL;
+                        break;
+                }
+}
+
+static int ir_remove(struct i2c_client *client)
+{
+        struct IR *ir = i2c_get_clientdata(client);
+
+        mutex_lock(&ir_devices_lock);
+
+        if (ir == NULL) {
+                /* We destroyed everything when the first client came through */
+                mutex_unlock(&ir_devices_lock);
+                return 0;
         }
 
-        /* unregister lirc driver */
-        /* FIXME make tx, rx senitive */
-        if (ir->l.minor >= 0 && ir->l.minor < MAX_IRCTL_DEVICES) {
-                lirc_unregister_driver(ir->l.minor);
-                ir_devices[ir->l.minor] = NULL;
+        /* Good-bye LIRC */
+        lirc_unregister_driver(ir->l.minor);
+
+        /* Good-bye Rx */
+        destroy_rx_kthread(ir->rx);
+        if (ir->rx != NULL) {
+                if (ir->rx->buf.fifo_initialized)
+                        lirc_buffer_free(&ir->rx->buf);
+                i2c_set_clientdata(ir->rx->c, NULL);
+                kfree(ir->rx);
         }
 
-        /* free memory */
-        /* FIXME make tx, rx senitive */
-        lirc_buffer_free(&rx->buf);
-        mutex_unlock(&ir->ir_lock);
+        /* Good-bye Tx */
+        i2c_set_clientdata(ir->tx->c, NULL);
+        kfree(ir->tx);
+
+        /* Good-bye IR */
+        del_ir_device(ir);
         kfree(ir);
 
+        mutex_unlock(&ir_devices_lock);
         return 0;
 }
 
-static int ir_probe(struct i2c_client *client, const struct i2c_device_id *id)
+
+/* ir_devices_lock must be held */
+static struct IR *find_ir_device_by_adapter(struct i2c_adapter *adapter)
 {
+        int i;
         struct IR *ir = NULL;
+
+        for (i = 0; i < MAX_IRCTL_DEVICES; i++)
+                if (ir_devices[i] != NULL &&
+                    ir_devices[i]->adapter == adapter) {
+                        ir = ir_devices[i];
+                        break;
+                }
+
+        return ir;
+}
+
+static int ir_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+        struct IR *ir;
         struct i2c_adapter *adap = client->adapter;
         int ret;
-        int have_rx = 0, have_tx = 0;
+        bool tx_probe = false;
 
         dprintk("%s: %s on i2c-%d (%s), client addr=0x%02x\n",
                 __func__, id->name, adap->nr, adap->name, client->addr);
 
         /*
-         * FIXME - This probe function probes both the Tx and Rx
-         * addresses of the IR microcontroller.
-         *
-         * However, the I2C subsystem is passing along one I2C client at a
-         * time, based on matches to the ir_transceiver_id[] table above.
-         * The expectation is that each i2c_client address will be probed
-         * individually by drivers so the I2C subsystem can mark all client
-         * addresses as claimed or not.
-         *
-         * This probe routine causes only one of the client addresses, TX or RX,
-         * to be claimed.  This will cause a problem if the I2C subsystem is
-         * subsequently triggered to probe unclaimed clients again.
-         */
-        /*
-         * The external IR receiver is at i2c address 0x71.
-         * The IR transmitter is at 0x70.
+         * The IR receiver    is at i2c address 0x71.
+         * The IR transmitter is at i2c address 0x70.
          */
 
-        if (id->driver_data & ID_FLAG_TX) {
-                have_tx = 1;
-        } else if (!disable_rx) {
-                have_rx = 1;
-        } else {
+        if (id->driver_data & ID_FLAG_TX)
+                tx_probe = true;
+        else if (tx_only) /* module option */
                 return -ENXIO;
-        }
 
-        printk(KERN_INFO "lirc_zilog: chip found with %s\n",
-                have_rx && have_tx ? "RX and TX" :
-                        have_rx ? "RX only" : "TX only");
+        zilog_info("%s: probing IR %s on %s (i2c-%d)\n",
+                   __func__, tx_probe ? "Tx" : "Rx", adap->name, adap->nr);
 
-        ir = kzalloc(sizeof(struct IR), GFP_KERNEL);
-        if (!ir)
-                goto out_nomem;
+        mutex_lock(&ir_devices_lock);
 
-        if (have_tx) {
-                ir->tx = kzalloc(sizeof(struct IR_tx), GFP_KERNEL);
-                if (ir->tx != NULL) {
-                        ir->tx->c = client;
-                        ir->tx->need_boot = 1;
-                        ir->tx->post_tx_ready_poll =
-                               (id->driver_data & ID_FLAG_HDPVR) ? false : true;
+        /* Use a single struct IR instance for both the Rx and Tx functions */
+        ir = find_ir_device_by_adapter(adap);
+        if (ir == NULL) {
+                ir = kzalloc(sizeof(struct IR), GFP_KERNEL);
+                if (ir == NULL) {
+                        ret = -ENOMEM;
+                        goto out_no_ir;
                 }
+                /* store for use in ir_probe() again, and open() later on */
+                ret = add_ir_device(ir);
+                if (ret)
+                        goto out_free_ir;
+
+                ir->adapter = adap;
+                mutex_init(&ir->ir_lock);
+
+                /* set lirc_dev stuff */
+                memcpy(&ir->l, &lirc_template, sizeof(struct lirc_driver));
+                ir->l.minor       = minor; /* module option */
+                ir->l.code_length = 13;
+                ir->l.rbuf        = NULL;
+                ir->l.fops        = &lirc_fops;
+                ir->l.data        = ir;
+                ir->l.dev         = &adap->dev;
+                ir->l.sample_rate = 0;
         }
 
-        if (have_rx) {
-                ir->rx = kzalloc(sizeof(struct IR_rx), GFP_KERNEL);
+        if (tx_probe) {
+                /* Set up a struct IR_tx instance */
+                ir->tx = kzalloc(sizeof(struct IR_tx), GFP_KERNEL);
+                if (ir->tx == NULL) {
+                        ret = -ENOMEM;
+                        goto out_free_xx;
+                }
 
+                ir->tx->c = client;
+                ir->tx->need_boot = 1;
+                ir->tx->post_tx_ready_poll =
+                               (id->driver_data & ID_FLAG_HDPVR) ? false : true;
+        } else {
+                /* Set up a struct IR_rx instance */
+                ir->rx = kzalloc(sizeof(struct IR_rx), GFP_KERNEL);
                 if (ir->rx == NULL) {
                         ret = -ENOMEM;
-                } else {
-                        ir->rx->c = client;
-                        ir->rx->hdpvr_data_fmt =
-                               (id->driver_data & ID_FLAG_HDPVR) ? true : false;
-                        mutex_init(&ir->rx->buf_lock);
-                        ret = lirc_buffer_init(&ir->rx->buf, 2, BUFLEN / 2);
+                        goto out_free_xx;
                 }
 
-                if (ret && (ir->rx != NULL)) {
-                        kfree(ir->rx);
-                        ir->rx = NULL;
-                }
-        }
+                ret = lirc_buffer_init(&ir->rx->buf, 2, BUFLEN / 2);
+                if (ret)
+                        goto out_free_xx;
 
-        mutex_init(&ir->ir_lock);
+                mutex_init(&ir->rx->buf_lock);
+                ir->rx->c = client;
+                ir->rx->hdpvr_data_fmt =
+                               (id->driver_data & ID_FLAG_HDPVR) ? true : false;
 
-        memcpy(&ir->l, &lirc_template, sizeof(struct lirc_driver));
-        ir->l.minor = -1;
+                /* set lirc_dev stuff */
+                ir->l.rbuf = &ir->rx->buf;
+        }
 
-        /* I2C attach to device */
         i2c_set_clientdata(client, ir);
 
+        /* Proceed only if we have the required Tx and Rx clients ready to go */
+        if (ir->tx == NULL ||
+            (ir->rx == NULL && !tx_only)) {
+                zilog_info("%s: probe of IR %s on %s (i2c-%d) done, waiting on "
+                           "IR %s\n", __func__, tx_probe ? "Tx" : "Rx",
+                           adap->name, adap->nr, tx_probe ? "Rx" : "Tx");
+                goto out_ok;
+        }
+
         /* initialise RX device */
         if (ir->rx != NULL) {
                 DECLARE_COMPLETION(tn);
@@ -1298,35 +1375,23 @@ static int ir_probe(struct i2c_client *client, const struct i2c_device_id *id)
                 ir->rx->task = kthread_run(lirc_thread, ir, "lirc_zilog");
                 if (IS_ERR(ir->rx->task)) {
                         ret = PTR_ERR(ir->rx->task);
-                        zilog_error("lirc_register_driver: cannot run "
-                                    "poll thread %d\n", ret);
-                        goto err;
+                        zilog_error("%s: could not start IR Rx polling thread"
+                                    "\n", __func__);
+                        goto out_free_xx;
                 }
                 wait_for_completion(&tn);
                 ir->rx->t_notify = NULL;
         }
 
-        /* set lirc_dev stuff */
-        ir->l.code_length = 13;
-        ir->l.rbuf        = (ir->rx == NULL) ? NULL : &ir->rx->buf;
-        ir->l.fops        = &lirc_fops;
-        ir->l.data        = ir;
-        ir->l.minor       = minor;
-        ir->l.dev         = &adap->dev;
-        ir->l.sample_rate = 0;
-
         /* register with lirc */
         ir->l.minor = lirc_register_driver(&ir->l);
         if (ir->l.minor < 0 || ir->l.minor >= MAX_IRCTL_DEVICES) {
-                zilog_error("ir_attach: \"minor\" must be between 0 and %d "
-                            "(%d)!\n", MAX_IRCTL_DEVICES-1, ir->l.minor);
+                zilog_error("%s: \"minor\" must be between 0 and %d (%d)!\n",
+                            __func__, MAX_IRCTL_DEVICES-1, ir->l.minor);
                 ret = -EBADRQC;
-                goto err;
+                goto out_free_thread;
         }
 
-        /* store this for getting back in open() later on */
-        ir_devices[ir->l.minor] = ir;
-
         /*
          * if we have the tx device, load the 'firmware'.  We do this
          * after registering with lirc as otherwise hotplug seems to take
@@ -1336,25 +1401,39 @@ static int ir_probe(struct i2c_client *client, const struct i2c_device_id *id)
                 /* Special TX init */
                 ret = tx_init(ir->tx);
                 if (ret != 0)
-                        goto err;
+                        goto out_unregister;
         }
 
+out_ok:
+        mutex_unlock(&ir_devices_lock);
         return 0;
 
-err:
-        /* FIXME - memory deallocation for all error cases needs work */
-        /* undo everything, hopefully... */
-        if (ir->rx != NULL)
-                ir_remove(ir->rx->c);
-        if (ir->tx != NULL)
-                ir_remove(ir->tx->c);
-        return ret;
-
-out_nomem:
-        /* FIXME - memory deallocation for all error cases needs work */
-        zilog_error("memory allocation failure\n");
+out_unregister:
+        lirc_unregister_driver(ir->l.minor);
+out_free_thread:
+        destroy_rx_kthread(ir->rx);
+out_free_xx:
+        if (ir->rx != NULL) {
+                if (ir->rx->buf.fifo_initialized)
+                        lirc_buffer_free(&ir->rx->buf);
+                if (ir->rx->c != NULL)
+                        i2c_set_clientdata(ir->rx->c, NULL);
+                kfree(ir->rx);
+        }
+        if (ir->tx != NULL) {
+                if (ir->tx->c != NULL)
+                        i2c_set_clientdata(ir->tx->c, NULL);
+                kfree(ir->tx);
+        }
+out_free_ir:
+        del_ir_device(ir);
         kfree(ir);
-        return -ENOMEM;
+out_no_ir:
+        zilog_error("%s: probing IR %s on %s (i2c-%d) failed with %d\n",
+                    __func__, tx_probe ? "Tx" : "Rx", adap->name, adap->nr,
+                   ret);
+        mutex_unlock(&ir_devices_lock);
+        return ret;
 }
 
 static int ir_command(struct i2c_client *client, unsigned int cmd, void *arg)
@@ -1370,6 +1449,7 @@ static int __init zilog_init(void)
         zilog_notify("Zilog/Hauppauge IR driver initializing\n");
 
         mutex_init(&tx_data_lock);
+        mutex_init(&ir_devices_lock);
 
         request_module("firmware_class");
 
@@ -1406,5 +1486,5 @@ MODULE_PARM_DESC(minor, "Preferred minor device number");
 module_param(debug, bool, 0644);
 MODULE_PARM_DESC(debug, "Enable debugging messages");
 
-module_param(disable_rx, bool, 0644);
-MODULE_PARM_DESC(disable_rx, "Disable the IR receiver device");
+module_param(tx_only, bool, 0644);
+MODULE_PARM_DESC(tx_only, "Only handle the IR transmit function");