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Date: Wed, 17 Jun 2020 20:52:14 +0200
From: Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
To: Linux Media Mailing List <linux-media@...r.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab+huawei@...nel.org>,
Marc Gonzalez <marc.w.gonzalez@...e.fr>,
Brad Love <brad@...tdimension.cc>, Sean Young <sean@...s.org>,
Arnd Bergmann <arnd@...db.de>, linux-kernel@...r.kernel.org
Subject: [RFC 4/4] media: dvb_frontend: disable zigzag mode if not possible
For the zigzag to work, the core needs to have a frequency
shift. Without that, the zigzag code will just try re-tuning
several times at the very same frequency, with seems wrong.
So, add a warning when this happens, and fall back to the
single-shot mode.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
---
drivers/media/dvb-core/dvb_frontend.c | 141 +++++++++++++++-----------
1 file changed, 79 insertions(+), 62 deletions(-)
diff --git a/drivers/media/dvb-core/dvb_frontend.c b/drivers/media/dvb-core/dvb_frontend.c
index ed85dc2a9183..cb577924121e 100644
--- a/drivers/media/dvb-core/dvb_frontend.c
+++ b/drivers/media/dvb-core/dvb_frontend.c
@@ -642,6 +642,9 @@ static void dvb_frontend_wakeup(struct dvb_frontend *fe)
wake_up_interruptible(&fepriv->wait_queue);
}
+static u32 dvb_frontend_get_stepsize(struct dvb_frontend *fe);
+static void prepare_tuning_algo_parameters(struct dvb_frontend *fe);
+
static int dvb_frontend_thread(void *data)
{
struct dvb_frontend *fe = data;
@@ -696,78 +699,92 @@ static int dvb_frontend_thread(void *data)
fepriv->reinitialise = 0;
}
- /* do an iteration of the tuning loop */
- if (fe->ops.get_frontend_algo) {
+ if (fe->ops.get_frontend_algo)
algo = fe->ops.get_frontend_algo(fe);
- switch (algo) {
- case DVBFE_ALGO_HW:
- dev_dbg(fe->dvb->device, "%s: Frontend ALGO = DVBFE_ALGO_HW\n", __func__);
+ else
+ algo = DVBFE_ALGO_SW;
- if (fepriv->state & FESTATE_RETUNE) {
- dev_dbg(fe->dvb->device, "%s: Retune requested, FESTATE_RETUNE\n", __func__);
- re_tune = true;
- fepriv->state = FESTATE_TUNED;
- } else {
- re_tune = false;
- }
+ /* do an iteration of the tuning loop */
+ switch (algo) {
+ case DVBFE_ALGO_SW:
+ prepare_tuning_algo_parameters(fe);
- if (fe->ops.tune)
- fe->ops.tune(fe, re_tune, fepriv->tune_mode_flags, &fepriv->delay, &s);
-
- if (s != fepriv->status && !(fepriv->tune_mode_flags & FE_TUNE_MODE_ONESHOT)) {
- dev_dbg(fe->dvb->device, "%s: state changed, adding current state\n", __func__);
- dvb_frontend_add_event(fe, s);
- fepriv->status = s;
- }
- break;
- case DVBFE_ALGO_SW:
+ if (fepriv->max_drift) {
dev_dbg(fe->dvb->device, "%s: Frontend ALGO = DVBFE_ALGO_SW\n", __func__);
dvb_frontend_swzigzag(fe);
break;
- case DVBFE_ALGO_CUSTOM:
- dev_dbg(fe->dvb->device, "%s: Frontend ALGO = DVBFE_ALGO_CUSTOM, state=%d\n", __func__, fepriv->state);
- if (fepriv->state & FESTATE_RETUNE) {
- dev_dbg(fe->dvb->device, "%s: Retune requested, FESTAT_RETUNE\n", __func__);
- fepriv->state = FESTATE_TUNED;
+ }
+
+ /*
+ * See prepare_tuning_algo_parameters():
+ * - Some standards may not use zigzag.
+ */
+ if (!dvb_frontend_get_stepsize(fe))
+ dev_warn(fe->dvb->device,
+ "disabling sigzag, as frontend doesn't set frequency step size\n");
+
+ /* fall through */
+ case DVBFE_ALGO_HW:
+ dev_dbg(fe->dvb->device, "%s: Frontend ALGO = DVBFE_ALGO_HW\n", __func__);
+
+ if (fepriv->state & FESTATE_RETUNE) {
+ dev_dbg(fe->dvb->device, "%s: Retune requested, FESTATE_RETUNE\n", __func__);
+ re_tune = true;
+ fepriv->state = FESTATE_TUNED;
+ } else {
+ re_tune = false;
+ }
+
+ if (fe->ops.tune)
+ fe->ops.tune(fe, re_tune, fepriv->tune_mode_flags, &fepriv->delay, &s);
+
+ if (s != fepriv->status && !(fepriv->tune_mode_flags & FE_TUNE_MODE_ONESHOT)) {
+ dev_dbg(fe->dvb->device, "%s: state changed, adding current state\n", __func__);
+ dvb_frontend_add_event(fe, s);
+ fepriv->status = s;
+ }
+ break;
+ case DVBFE_ALGO_CUSTOM:
+ dev_dbg(fe->dvb->device, "%s: Frontend ALGO = DVBFE_ALGO_CUSTOM, state=%d\n", __func__, fepriv->state);
+ if (fepriv->state & FESTATE_RETUNE) {
+ dev_dbg(fe->dvb->device, "%s: Retune requested, FESTAT_RETUNE\n", __func__);
+ fepriv->state = FESTATE_TUNED;
+ }
+ /* Case where we are going to search for a carrier
+ * User asked us to retune again for some reason, possibly
+ * requesting a search with a new set of parameters
+ */
+ if (fepriv->algo_status & DVBFE_ALGO_SEARCH_AGAIN) {
+ if (fe->ops.search) {
+ fepriv->algo_status = fe->ops.search(fe);
+ /* We did do a search as was requested, the flags are
+ * now unset as well and has the flags wrt to search.
+ */
+ } else {
+ fepriv->algo_status &= ~DVBFE_ALGO_SEARCH_AGAIN;
}
- /* Case where we are going to search for a carrier
- * User asked us to retune again for some reason, possibly
- * requesting a search with a new set of parameters
- */
- if (fepriv->algo_status & DVBFE_ALGO_SEARCH_AGAIN) {
- if (fe->ops.search) {
- fepriv->algo_status = fe->ops.search(fe);
- /* We did do a search as was requested, the flags are
- * now unset as well and has the flags wrt to search.
- */
- } else {
- fepriv->algo_status &= ~DVBFE_ALGO_SEARCH_AGAIN;
- }
- }
- /* Track the carrier if the search was successful */
- if (fepriv->algo_status != DVBFE_ALGO_SEARCH_SUCCESS) {
+ }
+ /* Track the carrier if the search was successful */
+ if (fepriv->algo_status != DVBFE_ALGO_SEARCH_SUCCESS) {
+ fepriv->algo_status |= DVBFE_ALGO_SEARCH_AGAIN;
+ fepriv->delay = HZ / 2;
+ }
+ dtv_property_legacy_params_sync(fe, c, &fepriv->parameters_out);
+ fe->ops.read_status(fe, &s);
+ if (s != fepriv->status) {
+ dvb_frontend_add_event(fe, s); /* update event list */
+ fepriv->status = s;
+ if (!(s & FE_HAS_LOCK)) {
+ fepriv->delay = HZ / 10;
fepriv->algo_status |= DVBFE_ALGO_SEARCH_AGAIN;
- fepriv->delay = HZ / 2;
+ } else {
+ fepriv->delay = 60 * HZ;
}
- dtv_property_legacy_params_sync(fe, c, &fepriv->parameters_out);
- fe->ops.read_status(fe, &s);
- if (s != fepriv->status) {
- dvb_frontend_add_event(fe, s); /* update event list */
- fepriv->status = s;
- if (!(s & FE_HAS_LOCK)) {
- fepriv->delay = HZ / 10;
- fepriv->algo_status |= DVBFE_ALGO_SEARCH_AGAIN;
- } else {
- fepriv->delay = 60 * HZ;
- }
- }
- break;
- default:
- dev_dbg(fe->dvb->device, "%s: UNDEFINED ALGO !\n", __func__);
- break;
}
- } else {
- dvb_frontend_swzigzag(fe);
+ break;
+ default:
+ dev_dbg(fe->dvb->device, "%s: UNDEFINED ALGO !\n", __func__);
+ break;
}
}
--
2.26.2
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