There is no reason to use the dma_request_slave_channel_compat() as no
filter function and parameter is provided.
Switch the driver to use dma_request_chan() instead.
Signed-off-by: Peter Ujfalusi <[email protected]>
---
Hi,
Trying to crack down on the dma_request_slave_channel_compat() in the tree...
Only compile tested!
Regards,
Peter
drivers/spi/spi-pic32.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)
diff --git a/drivers/spi/spi-pic32.c b/drivers/spi/spi-pic32.c
index 69f517ec59c6..2f90ca5118af 100644
--- a/drivers/spi/spi-pic32.c
+++ b/drivers/spi/spi-pic32.c
@@ -609,22 +609,18 @@ static void pic32_spi_cleanup(struct spi_device *spi)
static void pic32_spi_dma_prep(struct pic32_spi *pic32s, struct device *dev)
{
struct spi_master *master = pic32s->master;
- dma_cap_mask_t mask;
- dma_cap_zero(mask);
- dma_cap_set(DMA_SLAVE, mask);
-
- master->dma_rx = dma_request_slave_channel_compat(mask, NULL, NULL,
- dev, "spi-rx");
- if (!master->dma_rx) {
+ master->dma_rx = dma_request_chan(dev, "spi-rx");
+ if (IS_ERR(master->dma_rx)) {
dev_warn(dev, "RX channel not found.\n");
+ master->dma_rx = NULL;
goto out_err;
}
- master->dma_tx = dma_request_slave_channel_compat(mask, NULL, NULL,
- dev, "spi-tx");
- if (!master->dma_tx) {
+ master->dma_tx = dma_request_chan(dev, "spi-tx");
+ if (IS_ERR(master->dma_tx)) {
dev_warn(dev, "TX channel not found.\n");
+ master->dma_tx = NULL;
goto out_err;
}
@@ -637,11 +633,15 @@ static void pic32_spi_dma_prep(struct pic32_spi *pic32s, struct device *dev)
return;
out_err:
- if (master->dma_rx)
+ if (master->dma_rx) {
dma_release_channel(master->dma_rx);
+ master->dma_rx = NULL;
+ }
- if (master->dma_tx)
+ if (master->dma_tx) {
dma_release_channel(master->dma_tx);
+ master->dma_tx = NULL;
+ }
}
static void pic32_spi_dma_unprep(struct pic32_spi *pic32s)
--
Peter
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
Hi Peter,
On Thu, Nov 21, 2019 at 9:11 AM Peter Ujfalusi <[email protected]> wrote:
> There is no reason to use the dma_request_slave_channel_compat() as no
> filter function and parameter is provided.
>
> Switch the driver to use dma_request_chan() instead.
>
> Signed-off-by: Peter Ujfalusi <[email protected]>
> --- a/drivers/spi/spi-pic32.c
> +++ b/drivers/spi/spi-pic32.c
> @@ -609,22 +609,18 @@ static void pic32_spi_cleanup(struct spi_device *spi)
> static void pic32_spi_dma_prep(struct pic32_spi *pic32s, struct device *dev)
> {
> struct spi_master *master = pic32s->master;
> - dma_cap_mask_t mask;
>
> - dma_cap_zero(mask);
> - dma_cap_set(DMA_SLAVE, mask);
> -
> - master->dma_rx = dma_request_slave_channel_compat(mask, NULL, NULL,
> - dev, "spi-rx");
> - if (!master->dma_rx) {
> + master->dma_rx = dma_request_chan(dev, "spi-rx");
Why not dma_request_slave_channel()?
That way you...
> + if (IS_ERR(master->dma_rx)) {
... don't have to change the NULL check here, and...
> dev_warn(dev, "RX channel not found.\n");
> + master->dma_rx = NULL;
... don't have to override by NULL here.
(same for TX below).
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
Hi Geert,
On 21/11/2019 10.30, Geert Uytterhoeven wrote:
> Hi Peter,
>
> On Thu, Nov 21, 2019 at 9:11 AM Peter Ujfalusi <[email protected]> wrote:
>> There is no reason to use the dma_request_slave_channel_compat() as no
>> filter function and parameter is provided.
>>
>> Switch the driver to use dma_request_chan() instead.
>>
>> Signed-off-by: Peter Ujfalusi <[email protected]>
>
>> --- a/drivers/spi/spi-pic32.c
>> +++ b/drivers/spi/spi-pic32.c
>> @@ -609,22 +609,18 @@ static void pic32_spi_cleanup(struct spi_device *spi)
>> static void pic32_spi_dma_prep(struct pic32_spi *pic32s, struct device *dev)
>> {
>> struct spi_master *master = pic32s->master;
>> - dma_cap_mask_t mask;
>>
>> - dma_cap_zero(mask);
>> - dma_cap_set(DMA_SLAVE, mask);
>> -
>> - master->dma_rx = dma_request_slave_channel_compat(mask, NULL, NULL,
>> - dev, "spi-rx");
>> - if (!master->dma_rx) {
>> + master->dma_rx = dma_request_chan(dev, "spi-rx");
>
> Why not dma_request_slave_channel()?
The longer term plan is to retire dma_request_slave_channel() as well.
With dma_request_chan() deferred probing against DMA drivers is possible
and it also supports legacy boot with dma_slave_map.
At the end we should be left with only dma_request_chan() for slave
channels in the kernel.
> That way you...
>
>> + if (IS_ERR(master->dma_rx)) {
>
> ... don't have to change the NULL check here, and...
>
>> dev_warn(dev, "RX channel not found.\n");
>> + master->dma_rx = NULL;
>
> ... don't have to override by NULL here.
It is a small sacrifice, true, but if anyone cares the driver can
support deferred probing with dma_request_chan().
>
> (same for TX below).
>
> Gr{oetje,eeting}s,
>
> Geert
>
- Péter
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
Hi Peter,
On Thu, Nov 21, 2019 at 9:40 AM Peter Ujfalusi <[email protected]> wrote:
> On 21/11/2019 10.30, Geert Uytterhoeven wrote:
> > On Thu, Nov 21, 2019 at 9:11 AM Peter Ujfalusi <[email protected]> wrote:
> >> There is no reason to use the dma_request_slave_channel_compat() as no
> >> filter function and parameter is provided.
> >>
> >> Switch the driver to use dma_request_chan() instead.
> >>
> >> Signed-off-by: Peter Ujfalusi <[email protected]>
> >
> >> --- a/drivers/spi/spi-pic32.c
> >> +++ b/drivers/spi/spi-pic32.c
> >> @@ -609,22 +609,18 @@ static void pic32_spi_cleanup(struct spi_device *spi)
> >> static void pic32_spi_dma_prep(struct pic32_spi *pic32s, struct device *dev)
> >> {
> >> struct spi_master *master = pic32s->master;
> >> - dma_cap_mask_t mask;
> >>
> >> - dma_cap_zero(mask);
> >> - dma_cap_set(DMA_SLAVE, mask);
> >> -
> >> - master->dma_rx = dma_request_slave_channel_compat(mask, NULL, NULL,
> >> - dev, "spi-rx");
> >> - if (!master->dma_rx) {
> >> + master->dma_rx = dma_request_chan(dev, "spi-rx");
> >
> > Why not dma_request_slave_channel()?
>
> The longer term plan is to retire dma_request_slave_channel() as well.
> With dma_request_chan() deferred probing against DMA drivers is possible
> and it also supports legacy boot with dma_slave_map.
>
> At the end we should be left with only dma_request_chan() for slave
> channels in the kernel.
Thank you, deferred probing is a valid argument.
You may want to add that to the patch description.
Reviewed-by: Geert Uytterhoeven <[email protected]>
> > That way you...
> >
> >> + if (IS_ERR(master->dma_rx)) {
> >
> > ... don't have to change the NULL check here, and...
> >
> >> dev_warn(dev, "RX channel not found.\n");
> >> + master->dma_rx = NULL;
> >
> > ... don't have to override by NULL here.
>
> It is a small sacrifice, true, but if anyone cares the driver can
> support deferred probing with dma_request_chan().
Deferred probing in case of missing DMA controllers is always a bit
tricky, as there are multiple options:
1. Defer probing of the slave driver,
2a. Continue probing of the slave driver, fall back to PIO (which is
what this driver does)
2b. and Retry DMA setup later.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds