[media] cx88: kernel bz#9476: Fix tone setting for Nova-S+ model 92001

Hauppauge Nova-S-Plus DVB-S model 92001 does not lock on horizontal
polarisation. According with the info provided at the BZ, model
92002 does.

The difference is that, on model 92001, the tone select is done via
isl6421, while, on other devices, this is done via cx24123 code.
This patch adds a way to override the demod's set_tone at isl6421
driver. In order to avoid regressions, the override is enabled
only for cx88 Nova S plus model 92001. For all other models and
devices, the set_tone is provided by the demod driver.

Patch originally proposed at bz@9476[1] by Michel Meyers and
John Donoghue but applying the original patch would break support
for all other devices based on isl6421.

[1] https://bugzilla.kernel.org/show_bug.cgi?id=9476

Tested-by: Adam Sampson <ats@offog.org>
Tested-by: Hans-Peter Jansen <hpj@urpla.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2 files changed, 29 insertions, 3 deletions

diff --git a/drivers/media/dvb-frontends/isl6421.c b/drivers/media/dvb-frontends/isl6421.c
index 0cb3f0f74c9c..c77002fcc8e2 100644
--- a/drivers/media/dvb-frontends/isl6421.c
+++ b/drivers/media/dvb-frontends/isl6421.c
@@ -89,6 +89,30 @@ static int isl6421_enable_high_lnb_voltage(struct dvb_frontend *fe, long arg)
 	return (i2c_transfer(isl6421->i2c, &msg, 1) == 1) ? 0 : -EIO;
 }
 
+static int isl6421_set_tone(struct dvb_frontend* fe, fe_sec_tone_mode_t tone)
+{
+	struct isl6421 *isl6421 = (struct isl6421 *) fe->sec_priv;
+	struct i2c_msg msg = { .addr = isl6421->i2c_addr, .flags = 0,
+			       .buf = &isl6421->config,
+			       .len = sizeof(isl6421->config) };
+
+	switch (tone) {
+	case SEC_TONE_ON:
+		isl6421->config |= ISL6421_ENT1;
+		break;
+	case SEC_TONE_OFF:
+		isl6421->config &= ~ISL6421_ENT1;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	isl6421->config |= isl6421->override_or;
+	isl6421->config &= isl6421->override_and;
+
+	return (i2c_transfer(isl6421->i2c, &msg, 1) == 1) ? 0 : -EIO;
+}
+
 static void isl6421_release(struct dvb_frontend *fe)
 {
 	/* power off */
@@ -100,7 +124,7 @@ static void isl6421_release(struct dvb_frontend *fe)
 }
 
 struct dvb_frontend *isl6421_attach(struct dvb_frontend *fe, struct i2c_adapter *i2c, u8 i2c_addr,
-		   u8 override_set, u8 override_clear)
+		   u8 override_set, u8 override_clear, bool override_tone)
 {
 	struct isl6421 *isl6421 = kmalloc(sizeof(struct isl6421), GFP_KERNEL);
 	if (!isl6421)
@@ -131,6 +155,8 @@ struct dvb_frontend *isl6421_attach(struct dvb_frontend *fe, struct i2c_adapter
 	/* override frontend ops */
 	fe->ops.set_voltage = isl6421_set_voltage;
 	fe->ops.enable_high_lnb_voltage = isl6421_enable_high_lnb_voltage;
+	if (override_tone)
+		fe->ops.set_tone = isl6421_set_tone;
 
 	return fe;
 }
diff --git a/drivers/media/dvb-frontends/isl6421.h b/drivers/media/dvb-frontends/isl6421.h
index e7ca7d12b50a..630e7f8a150e 100644
--- a/drivers/media/dvb-frontends/isl6421.h
+++ b/drivers/media/dvb-frontends/isl6421.h
@@ -42,10 +42,10 @@
 #if IS_ENABLED(CONFIG_DVB_ISL6421)
 /* override_set and override_clear control which system register bits (above) to always set & clear */
 extern struct dvb_frontend *isl6421_attach(struct dvb_frontend *fe, struct i2c_adapter *i2c, u8 i2c_addr,
-			  u8 override_set, u8 override_clear);
+			  u8 override_set, u8 override_clear, bool override_tone);
 #else
 static inline struct dvb_frontend *isl6421_attach(struct dvb_frontend *fe, struct i2c_adapter *i2c, u8 i2c_addr,
-						  u8 override_set, u8 override_clear)
+						  u8 override_set, u8 override_clear, bool override_tone)
 {
 	printk(KERN_WARNING "%s: driver disabled by Kconfig\n", __func__);
 	return NULL;