[media] rc: Fix input deadlock and transmit error in redrat3 driver

Fixed submit urb logic so hardware doesn't hang trying to transmit
signal data

Removed unneeded enable/disable detector commands in
redrat3_transmit_ir (the hardware does this anyway) and converted
arguments to unsigned as per 5588dc2

Signed-off-by: Andrew Vincer <andrew@redrat.co.uk>
Cc: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 18 insertions, 34 deletions

diff --git a/drivers/media/rc/redrat3.c b/drivers/media/rc/redrat3.c
index 61287fcca61a..9bff23cb0a5b 100644
--- a/drivers/media/rc/redrat3.c
+++ b/drivers/media/rc/redrat3.c
@@ -286,12 +286,6 @@ static void redrat3_issue_async(struct redrat3_dev *rr3)
 
         rr3_ftr(rr3->dev, "Entering %s\n", __func__);
 
-        if (!rr3->det_enabled) {
-                dev_warn(rr3->dev, "not issuing async read, "
-                         "detector not enabled\n");
-                return;
-        }
-
         memset(rr3->bulk_in_buf, 0, rr3->ep_in->wMaxPacketSize);
         res = usb_submit_urb(rr3->read_urb, GFP_ATOMIC);
         if (res)
@@ -827,6 +821,7 @@ out:
 static void redrat3_handle_async(struct urb *urb, struct pt_regs *regs)
 {
         struct redrat3_dev *rr3;
+        int ret;
 
         if (!urb)
                 return;
@@ -840,15 +835,13 @@ static void redrat3_handle_async(struct urb *urb, struct pt_regs *regs)
 
         rr3_ftr(rr3->dev, "Entering %s\n", __func__);
 
-        if (!rr3->det_enabled) {
-                rr3_dbg(rr3->dev, "received a read callback but detector "
-                        "disabled - ignoring\n");
-                return;
-        }
-
         switch (urb->status) {
         case 0:
-                redrat3_get_ir_data(rr3, urb->actual_length);
+                ret = redrat3_get_ir_data(rr3, urb->actual_length);
+                if (!ret) {
+                        /* no error, prepare to read more */
+                        redrat3_issue_async(rr3);
+                }
                 break;
 
         case -ECONNRESET:
@@ -865,11 +858,6 @@ static void redrat3_handle_async(struct urb *urb, struct pt_regs *regs)
                 rr3->pkttype = 0;
                 break;
         }
-
-        if (!rr3->transmitting)
-                redrat3_issue_async(rr3);
-        else
-                rr3_dbg(rr3->dev, "IR transmit in progress\n");
 }
 
 static void redrat3_write_bulk_callback(struct urb *urb, struct pt_regs *regs)
@@ -896,21 +884,24 @@ static u16 mod_freq_to_val(unsigned int mod_freq)
         return (u16)(65536 - (mult / mod_freq));
 }
 
-static int redrat3_set_tx_carrier(struct rc_dev *dev, u32 carrier)
+static int redrat3_set_tx_carrier(struct rc_dev *rcdev, u32 carrier)
 {
-        struct redrat3_dev *rr3 = dev->priv;
+        struct redrat3_dev *rr3 = rcdev->priv;
+        struct device *dev = rr3->dev;
 
+        rr3_dbg(dev, "Setting modulation frequency to %u", carrier);
         rr3->carrier = carrier;
 
         return carrier;
 }
 
-static int redrat3_transmit_ir(struct rc_dev *rcdev, int *txbuf, u32 n)
+static int redrat3_transmit_ir(struct rc_dev *rcdev, unsigned *txbuf,
+                                unsigned count)
 {
         struct redrat3_dev *rr3 = rcdev->priv;
         struct device *dev = rr3->dev;
         struct redrat3_signal_header header;
-        int i, j, count, ret, ret_len, offset;
+        int i, j, ret, ret_len, offset;
         int lencheck, cur_sample_len, pipe;
         char *buffer = NULL, *sigdata = NULL;
         int *sample_lens = NULL;
@@ -928,20 +919,13 @@ static int redrat3_transmit_ir(struct rc_dev *rcdev, int *txbuf, u32 n)
                 return -EAGAIN;
         }
 
-        count = n / sizeof(int);
         if (count > (RR3_DRIVER_MAXLENS * 2))
                 return -EINVAL;
 
+        /* rr3 will disable rc detector on transmit */
+        rr3->det_enabled = false;
         rr3->transmitting = true;
 
-        redrat3_disable_detector(rr3);
-
-        if (rr3->det_enabled) {
-                dev_err(dev, "%s: cannot tx while rx is enabled\n", __func__);
-                ret = -EIO;
-                goto out;
-        }
-
         sample_lens = kzalloc(sizeof(int) * RR3_DRIVER_MAXLENS, GFP_KERNEL);
         if (!sample_lens) {
                 ret = -ENOMEM;
@@ -1055,7 +1039,7 @@ static int redrat3_transmit_ir(struct rc_dev *rcdev, int *txbuf, u32 n)
         if (ret < 0)
                 dev_err(dev, "Error: control msg send failed, rc %d\n", ret);
         else
-                ret = n;
+                ret = count;
 
 out:
         kfree(sample_lens);
@@ -1063,8 +1047,8 @@ out:
         kfree(sigdata);
 
         rr3->transmitting = false;
-
-        redrat3_enable_detector(rr3);
+        /* rr3 re-enables rc detector because it was enabled before */
+        rr3->det_enabled = true;
 
         return ret;
 }