V4L/DVB (3797): Always wait for diseqc queue to become ready before transmitting...

The previous DISEQC code didn't wait, so it was unreliable

Signed-off-by: Yeasah Pell <yeasah at schwide.net>
Signed-off-by: Andrew de Quincey <adq_dvb@lidskialf.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

diff --git a/drivers/media/dvb/frontends/cx24123.c b/drivers/media/dvb/frontends/cx24123.c
index 115ec16..fa6cdba 100644 (file)
--- a/drivers/media/dvb/frontends/cx24123.c
+++ b/drivers/media/dvb/frontends/cx24123.c
@@ -687,15 +687,27 @@ static int cx24123_set_voltage(struct dvb_frontend* fe, fe_sec_voltage_t voltage
        return 0;
 }
 
+/* wait for diseqc queue to become ready (or timeout) */
+static void cx24123_wait_for_diseqc(struct cx24123_state *state)
+{
+       unsigned long timeout = jiffies + msecs_to_jiffies(200);
+       while (!(cx24123_readreg(state, 0x29) & 0x40)) {
+               if(time_after(jiffies, timeout)) {
+                       printk("%s: diseqc queue not ready, command may be lost.\n", __FUNCTION__);
+                       break;
+               }
+               msleep(10);
+       }
+}
+
 static int cx24123_send_diseqc_msg(struct dvb_frontend* fe, struct dvb_diseqc_master_cmd *cmd)
 {
        struct cx24123_state *state = fe->demodulator_priv;
        int i, val;
-       unsigned long timeout;
 
        dprintk("%s:\n",__FUNCTION__);
 
-       /* check if continuous tone has been stoped */
+       /* check if continuous tone has been stopped */
        if (state->config->use_isl6421)
                val = cx24123_readlnbreg(state, 0x00) & 0x10;
        else
@@ -707,6 +719,9 @@ static int cx24123_send_diseqc_msg(struct dvb_frontend* fe, struct dvb_diseqc_ma
                return -ENOTSUPP;
        }
 
+       /* wait for diseqc queue ready */
+       cx24123_wait_for_diseqc(state);
+
        /* select tone mode */
        cx24123_writereg(state, 0x2a, cx24123_readreg(state, 0x2a) & 0xf8);
 
@@ -716,9 +731,8 @@ static int cx24123_send_diseqc_msg(struct dvb_frontend* fe, struct dvb_diseqc_ma
        val = cx24123_readreg(state, 0x29);
        cx24123_writereg(state, 0x29, ((val & 0x90) | 0x40) | ((cmd->msg_len-3) & 3));
 
-       timeout = jiffies + msecs_to_jiffies(100);
-       while (!time_after(jiffies, timeout) && !(cx24123_readreg(state, 0x29) & 0x40))
-               ; // wait for LNB ready
+       /* wait for diseqc message to finish sending */
+       cx24123_wait_for_diseqc(state);
 
        return 0;
 }
@@ -727,7 +741,6 @@ static int cx24123_diseqc_send_burst(struct dvb_frontend* fe, fe_sec_mini_cmd_t
 {
        struct cx24123_state *state = fe->demodulator_priv;
        int val;
-       unsigned long timeout;
 
        dprintk("%s:\n", __FUNCTION__);
 
@@ -743,6 +756,8 @@ static int cx24123_diseqc_send_burst(struct dvb_frontend* fe, fe_sec_mini_cmd_t
                return -ENOTSUPP;
        }
 
+       cx24123_wait_for_diseqc(state);
+
        /* select tone mode */
        val = cx24123_readreg(state, 0x2a) & 0xf8;
        cx24123_writereg(state, 0x2a, val | 0x04);
@@ -756,10 +771,7 @@ static int cx24123_diseqc_send_burst(struct dvb_frontend* fe, fe_sec_mini_cmd_t
        else
                return -EINVAL;
 
-
-       timeout = jiffies + msecs_to_jiffies(100);
-       while (!time_after(jiffies, timeout) && !(cx24123_readreg(state, 0x29) & 0x40))
-               ; // wait for LNB ready
+       cx24123_wait_for_diseqc(state);
 
        return 0;
 }