[v3,2/3] media: vsp1: Add support to deassert/assert reset line
Commit Message
As the resets DT property is mandatory, and is present in all .dtsi
in mainline, add support to perform deassert/assert using reference
counted reset handle.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
---
v2->v3:
* Added Rb tag from Philipp
* If reset_control_deassert() failed, return ret directly.
v1->v2:
* Used reference counted reset handle to perform deassert/assert
RFC->v1:
* Added reset support as separate patch
* Moved rstc just after the bus_master field in struct vsp1_device
RFC:
* https://patchwork.kernel.org/project/linux-renesas-soc/patch/20220112174612.10773-21-biju.das.jz@bp.renesas.com/
---
drivers/media/platform/vsp1/vsp1.h | 1 +
drivers/media/platform/vsp1/vsp1_drv.c | 12 ++++++++++++
2 files changed, 13 insertions(+)
Comments
Hi Biju,
On Fri, Mar 11, 2022 at 11:38 AM Biju Das <biju.das.jz@bp.renesas.com> wrote:
> As the resets DT property is mandatory, and is present in all .dtsi
> in mainline, add support to perform deassert/assert using reference
> counted reset handle.
>
> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
> Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
> ---
> v2->v3:
> * Added Rb tag from Philipp
> * If reset_control_deassert() failed, return ret directly.
Thanks for the update!
> --- a/drivers/media/platform/vsp1/vsp1_drv.c
> +++ b/drivers/media/platform/vsp1/vsp1_drv.c
> @@ -16,6 +16,7 @@
> #include <linux/of_device.h>
> #include <linux/platform_device.h>
> #include <linux/pm_runtime.h>
> +#include <linux/reset.h>
> #include <linux/videodev2.h>
>
> #include <media/rcar-fcp.h>
> @@ -569,6 +570,11 @@ static void vsp1_mask_all_interrupts(struct vsp1_device *vsp1)
> */
> int vsp1_device_get(struct vsp1_device *vsp1)
> {
> + int ret = reset_control_deassert(vsp1->rstc);
> +
> + if (ret < 0)
> + return ret;
> +
> return pm_runtime_resume_and_get(vsp1->dev);
You've removed too much :-(
If pm_runtime_resume_and_get() fails, so still need to assert the reset
again.
The rest LGTM.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
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,
> Subject: Re: [PATCH v3 2/3] media: vsp1: Add support to deassert/assert
> reset line
>
> Hi Biju,
>
> On Fri, Mar 11, 2022 at 11:38 AM Biju Das <biju.das.jz@bp.renesas.com>
> wrote:
> > As the resets DT property is mandatory, and is present in all .dtsi in
> > mainline, add support to perform deassert/assert using reference
> > counted reset handle.
> >
> > Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
> > Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
> > ---
> > v2->v3:
> > * Added Rb tag from Philipp
> > * If reset_control_deassert() failed, return ret directly.
>
> Thanks for the update!
>
> > --- a/drivers/media/platform/vsp1/vsp1_drv.c
> > +++ b/drivers/media/platform/vsp1/vsp1_drv.c
> > @@ -16,6 +16,7 @@
> > #include <linux/of_device.h>
> > #include <linux/platform_device.h>
> > #include <linux/pm_runtime.h>
> > +#include <linux/reset.h>
> > #include <linux/videodev2.h>
> >
> > #include <media/rcar-fcp.h>
> > @@ -569,6 +570,11 @@ static void vsp1_mask_all_interrupts(struct
> vsp1_device *vsp1)
> > */
> > int vsp1_device_get(struct vsp1_device *vsp1) {
> > + int ret = reset_control_deassert(vsp1->rstc);
> > +
> > + if (ret < 0)
> > + return ret;
> > +
> > return pm_runtime_resume_and_get(vsp1->dev);
>
> You've removed too much :-(
My Bad. Will restore error checking related to pm_runtime_resume_and_get.
Cheers,
Biju
> If pm_runtime_resume_and_get() fails, so still need to assert the reset
> again.
>
> The rest LGTM.
>
> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-
> m68k.org
>
> 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
@@ -79,6 +79,7 @@ struct vsp1_device {
void __iomem *mmio;
struct rcar_fcp_device *fcp;
struct device *bus_master;
+ struct reset_control *rstc;
struct vsp1_brx *brs;
struct vsp1_brx *bru;
@@ -16,6 +16,7 @@
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
+#include <linux/reset.h>
#include <linux/videodev2.h>
#include <media/rcar-fcp.h>
@@ -569,6 +570,11 @@ static void vsp1_mask_all_interrupts(struct vsp1_device *vsp1)
*/
int vsp1_device_get(struct vsp1_device *vsp1)
{
+ int ret = reset_control_deassert(vsp1->rstc);
+
+ if (ret < 0)
+ return ret;
+
return pm_runtime_resume_and_get(vsp1->dev);
}
@@ -581,6 +587,7 @@ int vsp1_device_get(struct vsp1_device *vsp1)
void vsp1_device_put(struct vsp1_device *vsp1)
{
pm_runtime_put_sync(vsp1->dev);
+ reset_control_assert(vsp1->rstc);
}
/* -----------------------------------------------------------------------------
@@ -827,6 +834,11 @@ static int vsp1_probe(struct platform_device *pdev)
if (irq < 0)
return irq;
+ vsp1->rstc = devm_reset_control_get_shared(&pdev->dev, NULL);
+ if (IS_ERR(vsp1->rstc))
+ return dev_err_probe(&pdev->dev, PTR_ERR(vsp1->rstc),
+ "failed to get reset ctrl\n");
+
/* FCP (optional). */
fcp_node = of_parse_phandle(pdev->dev.of_node, "renesas,fcp", 0);
if (fcp_node) {