| Message ID | 20220519124235.21100-1-tangbin@cmss.chinamobile.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ASoC: stm32: sai: Use of_device_get_match_data() to simplify code | expand |
Hello Tang,
Thanks for the patch. Unfortunately this patch introduces a regression.
In the SAI driver of_device_id struct the data is a simple enum cast to
void* pointer.
static const struct of_device_id stm32_sai_sub_ids[] = {
.data = (void *)STM_SAI_A_ID},
This data is an ID which can be set to 0x0.
Here we have no way to know to discriminate between an error returned by
of_device_get_match_data() or a data id set to 0x0.
The current patch requires a change in the driver.
Either changing STM_SAI_x_ID enums, or replacing data by a struct.
For instance:
struct stm32_sai_comp_data {
unsigned int id;
}
struct stm32_sai_comp_data stm32_sai_comp_data_a = {
.id = STM_SAI_A_ID;
}
struct of_device_id stm32_sai_sub_ids[] = {
.data = &stm32_sai_comp_data_a},
}
Regards
Olivier
On 5/19/22 14:42, Tang Bin wrote:
> Retrieve of match data, it's better and cleaner to use
> 'of_device_get_match_data' over 'of_match_device'.
>
> Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
> ---
> sound/soc/stm/stm32_sai_sub.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/sound/soc/stm/stm32_sai_sub.c b/sound/soc/stm/stm32_sai_sub.c
> index dd636af81..d300605a2 100644
> --- a/sound/soc/stm/stm32_sai_sub.c
> +++ b/sound/soc/stm/stm32_sai_sub.c
> @@ -1500,7 +1500,6 @@ static int stm32_sai_sub_parse_of(struct platform_device *pdev,
> static int stm32_sai_sub_probe(struct platform_device *pdev)
> {
> struct stm32_sai_sub_data *sai;
> - const struct of_device_id *of_id;
> const struct snd_dmaengine_pcm_config *conf = &stm32_sai_pcm_config;
> int ret;
>
> @@ -1508,10 +1507,9 @@ static int stm32_sai_sub_probe(struct platform_device *pdev)
> if (!sai)
> return -ENOMEM;
>
> - of_id = of_match_device(stm32_sai_sub_ids, &pdev->dev);
> - if (!of_id)
> + sai->id = (uintptr_t)of_device_get_match_data(&pdev->dev);
> + if (!sai->id)
> return -EINVAL;
> - sai->id = (uintptr_t)of_id->data;
>
> sai->pdev = pdev;
> mutex_init(&sai->ctrl_lock);
On Mon, May 23, 2022 at 03:28:48PM +0200, Olivier MOYSAN wrote: > The current patch requires a change in the driver. > Either changing STM_SAI_x_ID enums, or replacing data by a struct. > For instance: > struct stm32_sai_comp_data { > unsigned int id; > } > struct stm32_sai_comp_data stm32_sai_comp_data_a = { > .id = STM_SAI_A_ID; > } > struct of_device_id stm32_sai_sub_ids[] = { > .data = &stm32_sai_comp_data_a}, > } Either approach works for me (or a revert for that matter).
Hi Mark & Olivier： On 2022/5/24 2:57, Mark Brown wrote: > On Mon, May 23, 2022 at 03:28:48PM +0200, Olivier MOYSAN wrote: > >> The current patch requires a change in the driver. >> Either changing STM_SAI_x_ID enums, or replacing data by a struct. >> For instance: >> struct stm32_sai_comp_data { >> unsigned int id; >> } >> struct stm32_sai_comp_data stm32_sai_comp_data_a = { >> .id = STM_SAI_A_ID; >> } >> struct of_device_id stm32_sai_sub_ids[] = { >> .data = &stm32_sai_comp_data_a}, >> } > Either approach works for me (or a revert for that matter). Thanks for your advice, I was thoughtless. I think change the date of STM_SAI_x_ID maybe simple. But if we don't change the id, what about add a "#define" like the line 47: #define STM_SAI_IS_SUB(x) ((x)->id == STM_SAI_A_ID || (x)->id == STM_SAI_B_ID) then in the judgement, wu use: sai->id = (uintptr_t)of_device_get_match_data(&pdev->dev); if (!STM_SAI_IS_SUB(sai)) return -EINVAL; if you think that's ok, I will send patch v2 for you . Thanks Tang Bin
Hi Tang, On 5/24/22 03:44, tangbin wrote: > Hi Mark & Olivier： > > On 2022/5/24 2:57, Mark Brown wrote: >> On Mon, May 23, 2022 at 03:28:48PM +0200, Olivier MOYSAN wrote: >> >>> The current patch requires a change in the driver. >>> Either changing STM_SAI_x_ID enums, or replacing data by a struct. >>> For instance: >>> struct stm32_sai_comp_data { >>> unsigned int id; >>> } >>> struct stm32_sai_comp_data stm32_sai_comp_data_a = { >>> .id = STM_SAI_A_ID; >>> } >>> struct of_device_id stm32_sai_sub_ids[] = { >>> .data = &stm32_sai_comp_data_a}, >>> } >> Either approach works for me (or a revert for that matter). > > Thanks for your advice, I was thoughtless. > > I think change the date of STM_SAI_x_ID maybe simple. But if we > don't change the id, > > what about add a "#define" like the line 47: > > #define STM_SAI_IS_SUB(x) ((x)->id == STM_SAI_A_ID || (x)->id == > STM_SAI_B_ID) > > then in the judgement, wu use: > > sai->id = (uintptr_t)of_device_get_match_data(&pdev->dev); > > if (!STM_SAI_IS_SUB(sai)) > > return -EINVAL; > > > if you think that's ok, I will send patch v2 for you . > If we allow null value in STM_SAI_IS_SUB(sai) check, we can miss real NULL pointer error from of_device_get_match_data(). The simplest way is to change STM_SAI_x_ID enums I think. But honnestly, I feel more comfortable to let the driver unchanged. BRs Olivier > Thanks > > Tang Bin > >
Hi Olivier： On 2022/5/24 22:30, Olivier MOYSAN wrote: > Hi Tang, > > On 5/24/22 03:44, tangbin wrote: >> Hi Mark & Olivier： >> >> On 2022/5/24 2:57, Mark Brown wrote: >>> On Mon, May 23, 2022 at 03:28:48PM +0200, Olivier MOYSAN wrote: >>> >>>> The current patch requires a change in the driver. >>>> Either changing STM_SAI_x_ID enums, or replacing data by a struct. >>>> For instance: >>>> struct stm32_sai_comp_data { >>>> unsigned int id; >>>> } >>>> struct stm32_sai_comp_data stm32_sai_comp_data_a = { >>>> .id = STM_SAI_A_ID; >>>> } >>>> struct of_device_id stm32_sai_sub_ids[] = { >>>> .data = &stm32_sai_comp_data_a}, >>>> } >>> Either approach works for me (or a revert for that matter). >> >> Thanks for your advice, I was thoughtless. >> >> I think change the date of STM_SAI_x_ID maybe simple. But if we >> don't change the id, >> >> what about add a "#define" like the line 47: >> >> #define STM_SAI_IS_SUB(x) ((x)->id == STM_SAI_A_ID || (x)->id == >> STM_SAI_B_ID) >> >> then in the judgement, wu use: >> >> sai->id = (uintptr_t)of_device_get_match_data(&pdev->dev); >> >> if (!STM_SAI_IS_SUB(sai)) >> >> return -EINVAL; >> >> >> if you think that's ok, I will send patch v2 for you . >> > > If we allow null value in STM_SAI_IS_SUB(sai) check, we can miss real > NULL pointer error from of_device_get_match_data(). > > The simplest way is to change STM_SAI_x_ID enums I think. > But honnestly, I feel more comfortable to let the driver unchanged. > Oh，you are right, I am sorry. Please forget this patch, I'm sorry to have wasted your time. But I saw some codes is useless in the line 48 & line 49, I think we can remove it. If you think so, I will send this patch for you. Thanks Tang Bin > BRs > Olivier > >> Thanks >> >> Tang Bin >> >>
Hi Tang, On 5/25/22 09:36, tangbin wrote: > Hi Olivier： > > On 2022/5/24 22:30, Olivier MOYSAN wrote: >> Hi Tang, >> >> On 5/24/22 03:44, tangbin wrote: >>> Hi Mark & Olivier： >>> >>> On 2022/5/24 2:57, Mark Brown wrote: >>>> On Mon, May 23, 2022 at 03:28:48PM +0200, Olivier MOYSAN wrote: >>>> >>>>> The current patch requires a change in the driver. >>>>> Either changing STM_SAI_x_ID enums, or replacing data by a struct. >>>>> For instance: >>>>> struct stm32_sai_comp_data { >>>>> unsigned int id; >>>>> } >>>>> struct stm32_sai_comp_data stm32_sai_comp_data_a = { >>>>> .id = STM_SAI_A_ID; >>>>> } >>>>> struct of_device_id stm32_sai_sub_ids[] = { >>>>> .data = &stm32_sai_comp_data_a}, >>>>> } >>>> Either approach works for me (or a revert for that matter). >>> >>> Thanks for your advice, I was thoughtless. >>> >>> I think change the date of STM_SAI_x_ID maybe simple. But if we >>> don't change the id, >>> >>> what about add a "#define" like the line 47: >>> >>> #define STM_SAI_IS_SUB(x) ((x)->id == STM_SAI_A_ID || (x)->id == >>> STM_SAI_B_ID) >>> >>> then in the judgement, wu use: >>> >>> sai->id = (uintptr_t)of_device_get_match_data(&pdev->dev); >>> >>> if (!STM_SAI_IS_SUB(sai)) >>> >>> return -EINVAL; >>> >>> >>> if you think that's ok, I will send patch v2 for you . >>> >> >> If we allow null value in STM_SAI_IS_SUB(sai) check, we can miss real >> NULL pointer error from of_device_get_match_data(). >> >> The simplest way is to change STM_SAI_x_ID enums I think. >> But honnestly, I feel more comfortable to let the driver unchanged. >> > Oh，you are right, I am sorry. > > Please forget this patch, I'm sorry to have wasted your time. > > But I saw some codes is useless in the line 48 & line 49, I think we can > remove it. > Yes, these two defines are no more useful. Feel free to send a cleanup patch. BRs Olivier > If you think so, I will send this patch for you. > > > Thanks > > Tang Bin > > >> BRs >> Olivier >> >>> Thanks >>> >>> Tang Bin >>> >>> > >
diff --git a/sound/soc/stm/stm32_sai_sub.c b/sound/soc/stm/stm32_sai_sub.c index dd636af81..d300605a2 100644 --- a/sound/soc/stm/stm32_sai_sub.c +++ b/sound/soc/stm/stm32_sai_sub.c @@ -1500,7 +1500,6 @@ static int stm32_sai_sub_parse_of(struct platform_device *pdev, static int stm32_sai_sub_probe(struct platform_device *pdev) { struct stm32_sai_sub_data *sai; - const struct of_device_id *of_id; const struct snd_dmaengine_pcm_config *conf = &stm32_sai_pcm_config; int ret; @@ -1508,10 +1507,9 @@ static int stm32_sai_sub_probe(struct platform_device *pdev) if (!sai) return -ENOMEM; - of_id = of_match_device(stm32_sai_sub_ids, &pdev->dev); - if (!of_id) + sai->id = (uintptr_t)of_device_get_match_data(&pdev->dev); + if (!sai->id) return -EINVAL; - sai->id = (uintptr_t)of_id->data; sai->pdev = pdev; mutex_init(&sai->ctrl_lock);
Retrieve of match data, it's better and cleaner to use 'of_device_get_match_data' over 'of_match_device'. Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com> --- sound/soc/stm/stm32_sai_sub.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)