[PATCH 4.14 078/190] media: si2157: Better check for running tuner in init

From: Greg Kroah-Hartman
Date: Fri Jun 19 2020 - 10:48:35 EST


From: Brad Love <brad@xxxxxxxxxxxxxxxx>

[ Upstream commit e955f959ac52e145f27ff2be9078b646d0352af0 ]

Getting the Xtal trim property to check if running is less error prone.
Reset if_frequency if state is unknown.

Replaces the previous "garbage check".

Signed-off-by: Brad Love <brad@xxxxxxxxxxxxxxxx>
Signed-off-by: Sean Young <sean@xxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/media/tuners/si2157.c | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/media/tuners/si2157.c b/drivers/media/tuners/si2157.c
index e35b1faf0ddc..c826997f5433 100644
--- a/drivers/media/tuners/si2157.c
+++ b/drivers/media/tuners/si2157.c
@@ -84,24 +84,23 @@ static int si2157_init(struct dvb_frontend *fe)
struct si2157_cmd cmd;
const struct firmware *fw;
const char *fw_name;
- unsigned int uitmp, chip_id;
+ unsigned int chip_id, xtal_trim;

dev_dbg(&client->dev, "\n");

- /* Returned IF frequency is garbage when firmware is not running */
- memcpy(cmd.args, "\x15\x00\x06\x07", 4);
+ /* Try to get Xtal trim property, to verify tuner still running */
+ memcpy(cmd.args, "\x15\x00\x04\x02", 4);
cmd.wlen = 4;
cmd.rlen = 4;
ret = si2157_cmd_execute(client, &cmd);
- if (ret)
- goto err;

- uitmp = cmd.args[2] << 0 | cmd.args[3] << 8;
- dev_dbg(&client->dev, "if_frequency kHz=%u\n", uitmp);
+ xtal_trim = cmd.args[2] | (cmd.args[3] << 8);

- if (uitmp == dev->if_frequency / 1000)
+ if (ret == 0 && xtal_trim < 16)
goto warm;

+ dev->if_frequency = 0; /* we no longer know current tuner state */
+
/* power up */
if (dev->chiptype == SI2157_CHIPTYPE_SI2146) {
memcpy(cmd.args, "\xc0\x05\x01\x00\x00\x0b\x00\x00\x01", 9);
--
2.25.1