| Message ID | 20220307122202.2251639-2-codrin.ciubotariu@microchip.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Add driver for SAMA7G5's PDMC | expand |
Hi, On Mon, Mar 07, 2022 at 02:21:57PM +0200, Codrin Ciubotariu wrote: > Even if struct snd_dmaengine_pcm_config is used, prepare_slave_config() > callback might not be set. Check if this callback is set before using it. > > Fixes: fa654e085300 ("ASoC: dmaengine-pcm: Provide default config") > Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com> > --- > > Changes in v2,v3: > - none > > sound/soc/soc-generic-dmaengine-pcm.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c > index 285441d6aeed..2ab2ddc1294d 100644 > --- a/sound/soc/soc-generic-dmaengine-pcm.c > +++ b/sound/soc/soc-generic-dmaengine-pcm.c > @@ -86,10 +86,10 @@ static int dmaengine_pcm_hw_params(struct snd_soc_component *component, > > memset(&slave_config, 0, sizeof(slave_config)); > > - if (!pcm->config) > - prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config; > - else > + if (pcm->config && pcm->config->prepare_slave_config) > prepare_slave_config = pcm->config->prepare_slave_config; > + else > + prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config; > > if (prepare_slave_config) { > int ret = prepare_slave_config(substream, params, &slave_config); I wonder if this patch is correct. There are drivers like sound/soc/mxs/mxs-pcm.c which call snd_dmaengine_pcm_register() with a config which has the prepare_slave_config callback unset. For these drivers dmaengine_pcm_hw_params() previously was a no-op. Now with this patch snd_dmaengine_pcm_prepare_slave_config() and dmaengine_slave_config() are called. At least for the mxs-pcm driver calling dmaengine_slave_config() will return -ENOSYS. At least the "Check if this callback is set before using it" part is wrong, the callback is checked before using it with if (prepare_slave_config) { ... } I don't have any mxs hardware at hand to test this. I just stumbled upon the change of behaviour when rebasing https://patchwork.kernel.org/project/alsa-devel/patch/20220301122111.1073174-1-s.hauer@pengutronix.de/ on current master. Sascha
On 20.04.2022 12:15, Sascha Hauer wrote: > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > Hi, Hi Sascha, > > On Mon, Mar 07, 2022 at 02:21:57PM +0200, Codrin Ciubotariu wrote: >> Even if struct snd_dmaengine_pcm_config is used, prepare_slave_config() >> callback might not be set. Check if this callback is set before using it. >> >> Fixes: fa654e085300 ("ASoC: dmaengine-pcm: Provide default config") >> Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com> >> --- >> >> Changes in v2,v3: >> - none >> >> sound/soc/soc-generic-dmaengine-pcm.c | 6 +++--- >> 1 file changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c >> index 285441d6aeed..2ab2ddc1294d 100644 >> --- a/sound/soc/soc-generic-dmaengine-pcm.c >> +++ b/sound/soc/soc-generic-dmaengine-pcm.c >> @@ -86,10 +86,10 @@ static int dmaengine_pcm_hw_params(struct snd_soc_component *component, >> >> memset(&slave_config, 0, sizeof(slave_config)); >> >> - if (!pcm->config) >> - prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config; >> - else >> + if (pcm->config && pcm->config->prepare_slave_config) >> prepare_slave_config = pcm->config->prepare_slave_config; >> + else >> + prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config; >> >> if (prepare_slave_config) { >> int ret = prepare_slave_config(substream, params, &slave_config); > > I wonder if this patch is correct. There are drivers like > sound/soc/mxs/mxs-pcm.c which call snd_dmaengine_pcm_register() with a > config which has the prepare_slave_config callback unset. For these > drivers dmaengine_pcm_hw_params() previously was a no-op. Now with this > patch snd_dmaengine_pcm_prepare_slave_config() and > dmaengine_slave_config() are called. At least for the mxs-pcm driver > calling dmaengine_slave_config() will return -ENOSYS. > > At least the "Check if this callback is set before using it" part is > wrong, the callback is checked before using it with > > if (prepare_slave_config) { > ... > } > > I don't have any mxs hardware at hand to test this. I just stumbled upon > the change of behaviour when rebasing > https://patchwork.kernel.org/project/alsa-devel/patch/20220301122111.1073174-1-s.hauer@pengutronix.de/ > on current master. You are right. I changed the behavior from: if (pmc->config && !pcm->config->prepare_slave_config) <do nothing> to: if (pmc->config && !pcm->config->prepare_slave_config) snd_dmaengine_pcm_prepare_slave_config() It was not intended and I agree that the commit message is not accurate. I guess some drivers might not need dmaengine_slave_config()... However, in my case, for the mchp-pdmc driver, I do have pcm->config with pcm->config->prepare_slave_config NULL, but I still need snd_dmaengine_pcm_prepare_slave_config() to be called. Should we add a separate flag to call snd_dmaengine_pcm_prepare_slave_config() if pcm->config->prepare_slave_config is NULL? Nice catch! Best regards, Codrin
On Wed, Apr 20, 2022 at 09:58:06AM +0000, Codrin.Ciubotariu@microchip.com wrote: > On 20.04.2022 12:15, Sascha Hauer wrote: > > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > > > Hi, > > Hi Sascha, > > > > > On Mon, Mar 07, 2022 at 02:21:57PM +0200, Codrin Ciubotariu wrote: > >> Even if struct snd_dmaengine_pcm_config is used, prepare_slave_config() > >> callback might not be set. Check if this callback is set before using it. > >> > >> Fixes: fa654e085300 ("ASoC: dmaengine-pcm: Provide default config") > >> Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com> > >> --- > >> > >> Changes in v2,v3: > >> - none > >> > >> sound/soc/soc-generic-dmaengine-pcm.c | 6 +++--- > >> 1 file changed, 3 insertions(+), 3 deletions(-) > >> > >> diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c > >> index 285441d6aeed..2ab2ddc1294d 100644 > >> --- a/sound/soc/soc-generic-dmaengine-pcm.c > >> +++ b/sound/soc/soc-generic-dmaengine-pcm.c > >> @@ -86,10 +86,10 @@ static int dmaengine_pcm_hw_params(struct snd_soc_component *component, > >> > >> memset(&slave_config, 0, sizeof(slave_config)); > >> > >> - if (!pcm->config) > >> - prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config; > >> - else > >> + if (pcm->config && pcm->config->prepare_slave_config) > >> prepare_slave_config = pcm->config->prepare_slave_config; > >> + else > >> + prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config; > >> > >> if (prepare_slave_config) { > >> int ret = prepare_slave_config(substream, params, &slave_config); > > > > I wonder if this patch is correct. There are drivers like > > sound/soc/mxs/mxs-pcm.c which call snd_dmaengine_pcm_register() with a > > config which has the prepare_slave_config callback unset. For these > > drivers dmaengine_pcm_hw_params() previously was a no-op. Now with this > > patch snd_dmaengine_pcm_prepare_slave_config() and > > dmaengine_slave_config() are called. At least for the mxs-pcm driver > > calling dmaengine_slave_config() will return -ENOSYS. > > > > At least the "Check if this callback is set before using it" part is > > wrong, the callback is checked before using it with > > > > if (prepare_slave_config) { > > ... > > } > > > > I don't have any mxs hardware at hand to test this. I just stumbled upon > > the change of behaviour when rebasing > > https://patchwork.kernel.org/project/alsa-devel/patch/20220301122111.1073174-1-s.hauer@pengutronix.de/ > > on current master. > > You are right. I changed the behavior from: > if (pmc->config && !pcm->config->prepare_slave_config) > <do nothing> > to: > if (pmc->config && !pcm->config->prepare_slave_config) > snd_dmaengine_pcm_prepare_slave_config() > > It was not intended and I agree that the commit message is not accurate. > I guess some drivers might not need dmaengine_slave_config()... > However, in my case, for the mchp-pdmc driver, I do have pcm->config > with pcm->config->prepare_slave_config NULL, but I still need > snd_dmaengine_pcm_prepare_slave_config() to be called. Should we add a > separate flag to call snd_dmaengine_pcm_prepare_slave_config() if > pcm->config->prepare_slave_config is NULL? Other drivers set pcm->config->prepare_slave_config to snd_dmaengine_pcm_prepare_slave_config() explicitly: sound/soc/fsl/imx-pcm-dma.c:33: .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config, I think that's the way to go. Regards, Sascha
On 20.04.2022 13:06, Sascha Hauer wrote: > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > On Wed, Apr 20, 2022 at 09:58:06AM +0000, Codrin.Ciubotariu@microchip.com wrote: >> On 20.04.2022 12:15, Sascha Hauer wrote: >>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe >>> >>> Hi, >> >> Hi Sascha, >> >>> >>> On Mon, Mar 07, 2022 at 02:21:57PM +0200, Codrin Ciubotariu wrote: >>>> Even if struct snd_dmaengine_pcm_config is used, prepare_slave_config() >>>> callback might not be set. Check if this callback is set before using it. >>>> >>>> Fixes: fa654e085300 ("ASoC: dmaengine-pcm: Provide default config") >>>> Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com> >>>> --- >>>> >>>> Changes in v2,v3: >>>> - none >>>> >>>> sound/soc/soc-generic-dmaengine-pcm.c | 6 +++--- >>>> 1 file changed, 3 insertions(+), 3 deletions(-) >>>> >>>> diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c >>>> index 285441d6aeed..2ab2ddc1294d 100644 >>>> --- a/sound/soc/soc-generic-dmaengine-pcm.c >>>> +++ b/sound/soc/soc-generic-dmaengine-pcm.c >>>> @@ -86,10 +86,10 @@ static int dmaengine_pcm_hw_params(struct snd_soc_component *component, >>>> >>>> memset(&slave_config, 0, sizeof(slave_config)); >>>> >>>> - if (!pcm->config) >>>> - prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config; >>>> - else >>>> + if (pcm->config && pcm->config->prepare_slave_config) >>>> prepare_slave_config = pcm->config->prepare_slave_config; >>>> + else >>>> + prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config; >>>> >>>> if (prepare_slave_config) { >>>> int ret = prepare_slave_config(substream, params, &slave_config); >>> >>> I wonder if this patch is correct. There are drivers like >>> sound/soc/mxs/mxs-pcm.c which call snd_dmaengine_pcm_register() with a >>> config which has the prepare_slave_config callback unset. For these >>> drivers dmaengine_pcm_hw_params() previously was a no-op. Now with this >>> patch snd_dmaengine_pcm_prepare_slave_config() and >>> dmaengine_slave_config() are called. At least for the mxs-pcm driver >>> calling dmaengine_slave_config() will return -ENOSYS. >>> >>> At least the "Check if this callback is set before using it" part is >>> wrong, the callback is checked before using it with >>> >>> if (prepare_slave_config) { >>> ... >>> } >>> >>> I don't have any mxs hardware at hand to test this. I just stumbled upon >>> the change of behaviour when rebasing >>> https://patchwork.kernel.org/project/alsa-devel/patch/20220301122111.1073174-1-s.hauer@pengutronix.de/ >>> on current master. >> >> You are right. I changed the behavior from: >> if (pmc->config && !pcm->config->prepare_slave_config) >> <do nothing> >> to: >> if (pmc->config && !pcm->config->prepare_slave_config) >> snd_dmaengine_pcm_prepare_slave_config() >> >> It was not intended and I agree that the commit message is not accurate. >> I guess some drivers might not need dmaengine_slave_config()... >> However, in my case, for the mchp-pdmc driver, I do have pcm->config >> with pcm->config->prepare_slave_config NULL, but I still need >> snd_dmaengine_pcm_prepare_slave_config() to be called. Should we add a >> separate flag to call snd_dmaengine_pcm_prepare_slave_config() if >> pcm->config->prepare_slave_config is NULL? > > Other drivers set pcm->config->prepare_slave_config to > snd_dmaengine_pcm_prepare_slave_config() explicitly: > > sound/soc/fsl/imx-pcm-dma.c:33: .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config, > > I think that's the way to go. That's more elegant, right. I will revert this patch and use your suggestion for the mchp-pdmc driver. Thanks and best regards, Codrin
diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c index 285441d6aeed..2ab2ddc1294d 100644 --- a/sound/soc/soc-generic-dmaengine-pcm.c +++ b/sound/soc/soc-generic-dmaengine-pcm.c @@ -86,10 +86,10 @@ static int dmaengine_pcm_hw_params(struct snd_soc_component *component, memset(&slave_config, 0, sizeof(slave_config)); - if (!pcm->config) - prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config; - else + if (pcm->config && pcm->config->prepare_slave_config) prepare_slave_config = pcm->config->prepare_slave_config; + else + prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config; if (prepare_slave_config) { int ret = prepare_slave_config(substream, params, &slave_config);
Even if struct snd_dmaengine_pcm_config is used, prepare_slave_config() callback might not be set. Check if this callback is set before using it. Fixes: fa654e085300 ("ASoC: dmaengine-pcm: Provide default config") Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com> --- Changes in v2,v3: - none sound/soc/soc-generic-dmaengine-pcm.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)