On Wed, Jul 8, 2020 at 9:17 AM Yu-Hsuan Hsu <yuhsuan@xxxxxxxxxxxx> wrote: > > Guenter Roeck <groeck@xxxxxxxxxx> 於 2020年7月8日 週三 下午9:28寫道: > > > > On Wed, Jul 8, 2020 at 3:16 AM Enric Balletbo i Serra > > <enric.balletbo@xxxxxxxxxxxxx> wrote: > > > > > > Hi Yu-Hsuan, > > > > > > Thank you for your patch. > > > > > > On 8/7/20 9:11, Yu-Hsuan Hsu wrote: > > > > It is not guaranteed that I2S RX is disabled when the kernel booting. > > > > For example, if the kernel crashes while it is enabled, it will keep > > > > enabled until the next time EC reboots. Reset I2S RX when probing to > > > > fix this issue. > > > > > > > > Signed-off-by: Yu-Hsuan Hsu <yuhsuan@xxxxxxxxxxxx> > > > > --- > > > > include/linux/platform_data/cros_ec_commands.h | 1 + > > > > sound/soc/codecs/cros_ec_codec.c | 7 +++++++ > > > > 2 files changed, 8 insertions(+) > > > > > > > > diff --git a/include/linux/platform_data/cros_ec_commands.h b/include/linux/platform_data/cros_ec_commands.h > > > > index 69210881ebac8..11ce917ca924c 100644 > > > > --- a/include/linux/platform_data/cros_ec_commands.h > > > > +++ b/include/linux/platform_data/cros_ec_commands.h > > > > @@ -4598,6 +4598,7 @@ enum ec_codec_i2s_rx_subcmd { > > > > EC_CODEC_I2S_RX_SET_SAMPLE_DEPTH = 0x2, > > > > EC_CODEC_I2S_RX_SET_DAIFMT = 0x3, > > > > EC_CODEC_I2S_RX_SET_BCLK = 0x4, > > > > + EC_CODEC_I2S_RX_RESET = 0x5, > > > > > > Is this a new command not available in the firmware that is already in the field? > > > > > > > > > > EC_CODEC_I2S_RX_SUBCMD_COUNT, > > > > }; > > > > > > > > diff --git a/sound/soc/codecs/cros_ec_codec.c b/sound/soc/codecs/cros_ec_codec.c > > > > index 8d45c628e988e..5495214e73e68 100644 > > > > --- a/sound/soc/codecs/cros_ec_codec.c > > > > +++ b/sound/soc/codecs/cros_ec_codec.c > > > > @@ -1034,6 +1034,13 @@ static int cros_ec_codec_platform_probe(struct platform_device *pdev) > > > > } > > > > priv->ec_capabilities = r.capabilities; > > > > > > > > + /* Reset EC codec I2S RX. */ > > > > + p.cmd = EC_CODEC_I2S_RX_RESET; > > > > + ret = send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_I2S_RX, > > > > + (uint8_t *)&p, sizeof(p), NULL, 0); > > > > + if (ret) > > > > + dev_err(dev, "failed to EC_CODEC_I2S_RESET: %d\n", ret); > > > > + > > > > > > With an old firmware I suspect this message will appear on every boot, right? > > > So, to solve the issue and get rid of this error you're forced to upgrade the > > > firmware. Is that true? > > > > > > > It might possibly make more sense to fail this silently and to send > > EC_CODEC_I2S_RX_DISABLE as backup if it is not supported (-ENOTSUPP > > can possibly be used as trigger if the call returns it). > > > > Also, I don't accept dev_err() if the error is ignored for patches in > > my scope of responsibility. > > > > Guenter > Thanks for the suggestion. Our plan is to upstream this patch first. > And then we will merge it into the kernel after the firmware is > updated. Is it feasible? (I'm not sure whether there is the better way > if I want to update EC and the kernel at the same time.) > > I think calling EC_CODEC_I2S_RX_DISABLE does not make sense because it > checks the value of i2s_rx_enabled first. If i2s_rx_enabled is false, > it will skip the function. However, we don't need to reset while the > i2s_rx_enabled is already false. > Exactly my point. If i2s_rx_enabled is false, nothing needs to be done, and it doesn't hurt if the EC does nothing. If i2s_rx_enabled is true, it needs to be set to false, which is accomplished by sending EC_CODEC_I2S_RX_DISABLE. > In addition, since it is a sub-command, it will return > EC_RES_INVALID_PARAM but not ENOTSUPP if the command is not supported. > And then EC_RES_INVALID_PARAM will turn into -EPROTO finally so it's > difficult to do other operators basing on the return value. > You might have to convince Enric to permit another error code to translate EC_RES_INVALID_PARAM. After all, that would meet his requirement that the error code must be used in the kernel to accept a translation. Guenter > Thanks, > Yu-Hsuan > > > > > > > platform_set_drvdata(pdev, priv); > > > > > > > > ret = devm_snd_soc_register_component(dev, &i2s_rx_component_driver, > > > >