17.12.2019 19:39, Sowjanya Komatineni пишет: > > On 12/17/19 8:16 AM, Dmitry Osipenko wrote: >> 17.12.2019 19:12, Sowjanya Komatineni пишет: >>> On 12/17/19 7:36 AM, Dmitry Osipenko wrote: >>>> 17.12.2019 04:29, Sowjanya Komatineni пишет: >>>>> On 12/7/19 11:20 AM, Sowjanya Komatineni wrote: >>>>>> On 12/7/19 6:58 AM, Dmitry Osipenko wrote: >>>>>>> 06.12.2019 05:48, Sowjanya Komatineni пишет: >>>>>>>> Current ASoC driver uses extern1 as cdev1 clock from Tegra30 >>>>>>>> onwards >>>>>>>> through device tree. >>>>>>>> >>>>>>>> Actual audio mclk is clk_out_1 and to use PLLA for mclk rate >>>>>>>> control, >>>>>>>> need to clk_out_1_mux parent to extern1 and extern1 parent to >>>>>>>> PLLA_OUT0. >>>>>>>> >>>>>>>> Currently Tegra clock driver init sets the parents and enables both >>>>>>>> clk_out_1 and extern1 clocks. But these clocks parent and enables >>>>>>>> should >>>>>>>> be controlled by ASoC driver. >>>>>>>> >>>>>>>> Clock parents can be specified in device tree using assigned-clocks >>>>>>>> and assigned-clock-parents. >>>>>>>> >>>>>>>> To enable audio mclk, both clk_out_1 and extern1 clocks need to be >>>>>>>> enabled. >>>>>>>> >>>>>>>> This patch configures parents for clk_out_1 and extern1 clocks if >>>>>>>> device >>>>>>>> tree does not specify clock parents inorder to support old device >>>>>>>> tree >>>>>>>> and controls mclk using both clk_out_1 and extern1 clocks. >>>>>>>> >>>>>>>> Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx> >>>>>>>> --- >>>>>>>> sound/soc/tegra/tegra_asoc_utils.c | 66 >>>>>>>> ++++++++++++++++++++++++++++++++++++++ >>>>>>>> sound/soc/tegra/tegra_asoc_utils.h | 1 + >>>>>>>> 2 files changed, 67 insertions(+) >>>>>>>> >>>>>>>> diff --git a/sound/soc/tegra/tegra_asoc_utils.c >>>>>>>> b/sound/soc/tegra/tegra_asoc_utils.c >>>>>>>> index 536a578e9512..8e3a3740df7c 100644 >>>>>>>> --- a/sound/soc/tegra/tegra_asoc_utils.c >>>>>>>> +++ b/sound/soc/tegra/tegra_asoc_utils.c >>>>>>>> @@ -60,6 +60,7 @@ int tegra_asoc_utils_set_rate(struct >>>>>>>> tegra_asoc_utils_data *data, int srate, >>>>>>>> data->set_mclk = 0; >>>>>>>> clk_disable_unprepare(data->clk_cdev1); >>>>>>>> + clk_disable_unprepare(data->clk_extern1); >>>>>>>> clk_disable_unprepare(data->clk_pll_a_out0); >>>>>>>> clk_disable_unprepare(data->clk_pll_a); >>>>>>>> @@ -89,6 +90,14 @@ int tegra_asoc_utils_set_rate(struct >>>>>>>> tegra_asoc_utils_data *data, int srate, >>>>>>>> return err; >>>>>>>> } >>>>>>>> + if (!IS_ERR_OR_NULL(data->clk_extern1)) { >>>>>>>> + err = clk_prepare_enable(data->clk_extern1); >>>>>>>> + if (err) { >>>>>>>> + dev_err(data->dev, "Can't enable extern1: %d\n", err); >>>>>>>> + return err; >>>>>>>> + } >>>>>>>> + } >>>>>>>> + >>>>>>>> err = clk_prepare_enable(data->clk_cdev1); >>>>>>>> if (err) { >>>>>>>> dev_err(data->dev, "Can't enable cdev1: %d\n", err); >>>>>>>> @@ -109,6 +118,7 @@ int tegra_asoc_utils_set_ac97_rate(struct >>>>>>>> tegra_asoc_utils_data *data) >>>>>>>> int err; >>>>>>>> clk_disable_unprepare(data->clk_cdev1); >>>>>>>> + clk_disable_unprepare(data->clk_extern1); >>>>>>>> clk_disable_unprepare(data->clk_pll_a_out0); >>>>>>>> clk_disable_unprepare(data->clk_pll_a); >>>>>>>> @@ -142,6 +152,14 @@ int tegra_asoc_utils_set_ac97_rate(struct >>>>>>>> tegra_asoc_utils_data *data) >>>>>>>> return err; >>>>>>>> } >>>>>>>> + if (!IS_ERR_OR_NULL(data->clk_extern1)) { >>>>>>>> + err = clk_prepare_enable(data->clk_extern1); >>>>>>>> + if (err) { >>>>>>>> + dev_err(data->dev, "Can't enable extern1: %d\n", err); >>>>>>>> + return err; >>>>>>>> + } >>>>>>>> + } >>>>>>> Why this is needed given that clk_extern1 is either a child of >>>>>>> MCLK or >>>>>>> MCLK itself (on T20)? The child clocks are enabled when the >>>>>>> parent is >>>>>>> enabled. >>>>>> For T30 and later, clk_extern1 is one of the source for >>>>>> clk_out_1_mux. >>>>>> clk_extern1 is in CAR and it has its own gate and mux. >>>>>> >>>>>> As audio mclk related clocks (clk_out_1, clk_out_1_mux, and extern1) >>>>>> are moved into ASoC driver from clock driver >>>>>> >>>>>> need to enable extern1 gate as well along with clk_out1 for T30 >>>>>> through T210. >>>>>> >>>>>> Just FYI, extern1 enable here happens only when data->clk_extern1 is >>>>>> available which is for T30 onwards. >>>>>> >>>>>>>> err = clk_prepare_enable(data->clk_cdev1); >>>>>>>> if (err) { >>>>>>>> dev_err(data->dev, "Can't enable cdev1: %d\n", err); >>>>>>>> @@ -158,6 +176,7 @@ >>>>>>>> EXPORT_SYMBOL_GPL(tegra_asoc_utils_set_ac97_rate); >>>>>>>> int tegra_asoc_utils_init(struct tegra_asoc_utils_data *data, >>>>>>>> struct device *dev) >>>>>>>> { >>>>>>>> + struct clk *clk_out_1_mux; >>>>>>>> int ret; >>>>>>>> data->dev = dev; >>>>>>>> @@ -196,6 +215,51 @@ int tegra_asoc_utils_init(struct >>>>>>>> tegra_asoc_utils_data *data, >>>>>>>> goto err_put_pll_a_out0; >>>>>>>> } >>>>>>> In a previous patch you added fallback to EXTPERIPH when >>>>>>> clk_get(MCLK) >>>>>>> fails. This will work perfectly fine for the older kernels which >>>>>>> have >>>>>>> all clocks in the same single CaR driver, but this may not work that >>>>>>> great for the newer kernels because PMC driver isn't registered >>>>>>> early >>>>>>> during boot and thus it is possible to get a legit -EPROBE_DEFER >>>>>>> which >>>>>>> shouldn't be ignored. In other words, you need to add into this >>>>>>> patch a >>>>>>> check for the error code returned by clk_get(MCLK) and fallback >>>>>>> only for >>>>>>> -EINVAL. >>>>>> yeah right, will add check in next version. >>>>>>>> + /* >>>>>>>> + * If clock parents are not set in DT, configure here to use >>>>>>>> clk_out_1 >>>>>>>> + * as mclk and extern1 as parent for Tegra30 and higher. >>>>>>>> + */ >>>>>>>> + if (!of_find_property(dev->of_node, "assigned-clock-parents", >>>>>>>> NULL) && >>>>>>>> + data->soc > TEGRA_ASOC_UTILS_SOC_TEGRA20) { >>>>>>>> + data->clk_extern1 = clk_get_sys("clk_out_1", "extern1"); >>>>>>>> + if (IS_ERR(data->clk_extern1)) { >>>>>>>> + dev_err(data->dev, "Can't retrieve clk extern1\n"); >>>>>>>> + ret = PTR_ERR(data->clk_extern1); >>>>>>>> + goto err_put_cdev1; >>>>>>>> + } >>>>>>>> + >>>>>>>> + ret = clk_set_parent(data->clk_extern1, >>>>>>>> data->clk_pll_a_out0); >>>>>>>> + if (ret < 0) { >>>>>>>> + dev_err(data->dev, >>>>>>>> + "Set parent failed for clk extern1: %d\n", >>>>>>>> + ret); >>>>>>>> + goto err_put_cdev1; >>>>>>>> + } >>>>>>>> + >>>>>>>> + clk_out_1_mux = clk_get_sys(NULL, "clk_out_1_mux"); >>>>>>> Note1: clk_get(dev, "clk_out_1_mux") should work here by letting clk >>>>>>> core to fall back to the clk_get_sys() by itself. Either way should >>>>>>> be good. >>>>> clk_get uses device rather and dev_id will be name of this device and >>>>> when clk_get fall back to __clk_get_sys() it still will use dev id of >>>>> this device rather than actual dev_id that pmc clocks are added to the >>>>> lookup. So clk_get_sys() seems to be correct to use as we can specify >>>>> exact dev_id and con_id. >>>> It should be better to use something "resource managed", thus >>>> devm_clk_get() should be a better choice. >>>> >>>>> Also, clk_find retrieves clock from lookup only when it finds matching >>>>> clock with both dev_id and con_id as pmc clocks are registered with >>>>> both >>>>> dev_id and con_id. >>>>> >>>>> I see existing clock driver adds both extern and pmc clocks >>>>> (clk_out) to >>>>> lookup with same dev_id of clk_out_1/2/3 and con_id of extern1/2/3 and >>>>> with this always extern clock will be retrieved and this is probably >>>>> because old DT and audio driver always uses extern1 rather than actual >>>>> clk_out_1 >>>>> >>>>> But this need to be fixed now as we changed to use clk_out directly >>>>> rather than extern (even for other pmc clocks) to match actual hw >>>>> design. >>>>> >>>>> Will fix this as well to register pmc clocks using con_id as >>>>> clk_out_1/2/3 in pmc driver and extern clocks using con_id of >>>>> extern1/2/3 with dev_id being NULL so we can retrieve these clocks by >>>>> just using con_id only using clk_get_sys as we switched to use >>>>> clk_out_1 >>>>> directly as pmc clock rather than extern from DT and no longer need to >>>>> pair pmc clocks to extern clocks. >>>> I'm not sure it's worth the effort to care about con_ids if implicit >>>> fallback to clk_get_sys(NULL, "...") does the right thing for the audio >>>> driver. >>>> >>>> IIRC, CCF uses variant of matching clocks by names, although I'm not >>>> sure whether that applies to older stable kernels. >>>> >>>> [snip] >>> Current clock driver adds EXTERN clock to lookup with dev_id as >>> clk_out_1/2/3 and con_id as extern_1/2/3 >>> >>> With this we can retrieve clock from lookup only with clk_get_sys where >>> we can pass dev_id as clk_out_1/2/3 and con_id as extern_1/2/3. >>> >>> We cant use devm_clk_get() or clk_get() for retrieving clocks from >>> lookup by passing device object from sound driver as dev_id will be diff >>> and clk_find will return NULL. >> Have you actually tried to test that it fails? I think it's a false >> assumption. > > Yes I tried and looking at devm_clk_get it falls back to __clk_get_sys > which uses dev_id as dev_name of the device we pass from audio driver. > > looking into clk_find API implementation it doesn't find the clock from > lookup unless both dev_id and con_id matches if a clock is added to > lookup with both dev_id and clk_id > > >>> But with the fix of having dev_id as NULL and use only con_id to add to >>> lookup, we can use resource managed APIs devm_clk_get. >>> >>> So was saying will fix this in clock driver as part of removing >>> clk_out_1/2/3 ids and pmc init from clock driver so we can use >>> devm_clk_get API in audio driver. >>> Ok _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx https://mailman.alsa-project.org/mailman/listinfo/alsa-devel