[PATCH v2 5/7] staging: board: Add support for devices with complex dependencies
Geert Uytterhoeven
geert at linux-m68k.org
Fri Sep 4 08:03:02 PDT 2015
Hi Ulf,
On Fri, 4 Sep 2015, Ulf Hansson wrote:
> On 3 September 2015 at 15:35, Geert Uytterhoeven <geert at linux-m68k.org> wrote:
> > On Thu, Sep 3, 2015 at 2:53 PM, Ulf Hansson <ulf.hansson at linaro.org> wrote:
> >> On 17 June 2015 at 10:38, Geert Uytterhoeven <geert+renesas at glider.be> wrote:
> >>> Add support for easy registering of one ore more platform devices that
> >>> may:
> >>> - need clocks that are described in DT,
> >>> - be part of a PM Domain.
> >
> >>> diff --git a/drivers/staging/board/board.c b/drivers/staging/board/board.c
> >>> index 8712f566b31196e0..29d456e29f38feac 100644
> >>> --- a/drivers/staging/board/board.c
> >>> +++ b/drivers/staging/board/board.c
> >
> >>> +int __init board_staging_register_device(const struct board_staging_dev *dev)
> >>> +{
> >>> + struct platform_device *pdev = dev->pdev;
> >>> + unsigned int i;
> >>> + int error;
> >>> +
> >>> + pr_debug("Trying to register device %s\n", pdev->name);
> >>> + if (board_staging_dt_node_available(pdev->resource,
> >>> + pdev->num_resources)) {
> >>> + pr_warn("Skipping %s, already in DT\n", pdev->name);
> >>> + return -EEXIST;
> >>> + }
> >>> +
> >>> + board_staging_gic_fixup_resources(pdev->resource, pdev->num_resources);
> >>> +
> >>> + for (i = 0; i < dev->nclocks; i++)
> >>> + board_staging_register_clock(&dev->clocks[i]);
> >>> +
> >>> + error = platform_device_register(pdev);
> >>> + if (error) {
> >>> + pr_err("Failed to register device %s (%d)\n", pdev->name,
> >>> + error);
> >>> + return error;
> >>> + }
> >>> +
> >>> + if (dev->domain)
> >>> + __pm_genpd_name_add_device(dev->domain, &pdev->dev, NULL);
> >>
> >> Urgh, this managed to slip through my filters.
> >>
> >> It seems like we almost managed to remove all users of the
> >> "..._name_add..." APIs for genpd. If hasn't been for $subject patch.
> >> :-)
> >>
> >> Now, I realize this is already too late here, but let's try to fix
> >> this before it turns into a bigger issue.
> >>
> >> Geert, do you think it's possible to convert into using the non-named
> >> bases APIs?
> >
> > That will be difficult. This code is meant to use drivers that are not yet
> > DT-aware on DT-based systems. Hence it uses platform devices with named PM
> > domains, while the PM domains are described in DT.
> > I don't think there's another way to look up a PM domain by name, is there?
>
> As a matter of fact there are, especially for those genpds that has
> been created through DT as in this case. The API to use is
> of_genpd_get_from_provider() to find the struct generic_pm_domain.
Thanks!
> Yes, I do realize that you need to manage the parsing of the domain
> name to make sure it's the one you want, but I would rather keep that
> "hack" in this driver than in the generic API.
OK. It turned out not to be that complex, cfr. the patch below.
For now this supports PM domains with "#power-domain-cells = <0>" only,
but of course it can be extended if the need arises.
I've also tried:
np = of_find_compatible_node(NULL, NULL, "renesas,sysc-rmobile");
np = of_find_node_by_name(np, "a4lc");
(the second step is needed because of the domain hierarchy in DT), but that
would require adding the compatible string to struct board_staging_dev,
and doesn't work if you have multiple identical power providers.
I hope you like it?
>From 5fb11904845eb929a5b3382a9d5153c151cde1cf Mon Sep 17 00:00:00 2001
From: Geert Uytterhoeven <geert+renesas at glider.be>
Date: Fri, 4 Sep 2015 16:52:33 +0200
Subject: [PATCH/RFC] staging: board: Migrate away from
__pm_genpd_name_add_device()
The named genpd APIs are deprecated. Hence convert the board staging
code from using genpd names to DT node paths.
For now this supports PM domains with "#power-domain-cells = <0>" only.
Signed-off-by: Geert Uytterhoeven <geert+renesas at glider.be>
---
drivers/staging/board/armadillo800eva.c | 2 +-
drivers/staging/board/board.c | 36 ++++++++++++++++++++++++++++++++-
2 files changed, 36 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/board/armadillo800eva.c b/drivers/staging/board/armadillo800eva.c
index 0165591a52443c46..912c96b0536def7c 100644
--- a/drivers/staging/board/armadillo800eva.c
+++ b/drivers/staging/board/armadillo800eva.c
@@ -91,7 +91,7 @@ static const struct board_staging_dev armadillo800eva_devices[] __initconst = {
.pdev = &lcdc0_device,
.clocks = lcdc0_clocks,
.nclocks = ARRAY_SIZE(lcdc0_clocks),
- .domain = "a4lc",
+ .domain = "/system-controller at e6180000/pm-domains/c5/a4lc at 1"
},
};
diff --git a/drivers/staging/board/board.c b/drivers/staging/board/board.c
index 29d456e29f38feac..3eb5eb8f069c236d 100644
--- a/drivers/staging/board/board.c
+++ b/drivers/staging/board/board.c
@@ -135,6 +135,40 @@ int __init board_staging_register_clock(const struct board_staging_clk *bsc)
return error;
}
+#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
+static int board_staging_add_dev_domain(struct platform_device *pdev,
+ const char *domain)
+{
+ struct of_phandle_args pd_args;
+ struct generic_pm_domain *pd;
+ struct device_node *np;
+
+ np = of_find_node_by_path(domain);
+ if (!np) {
+ pr_err("Cannot find domain node %s\n", domain);
+ return -ENOENT;
+ }
+
+ pd_args.np = np;
+ pd_args.args_count = 0;
+ pd = of_genpd_get_from_provider(&pd_args);
+ if (IS_ERR(pd)) {
+ pr_err("Cannot find genpd %s (%ld)\n", domain, PTR_ERR(pd));
+ return PTR_ERR(pd);
+
+ }
+ pr_debug("Found genpd %s for device %s\n", pd->name, pdev->name);
+
+ return pm_genpd_add_device(pd, &pdev->dev);
+}
+#else
+static inline int board_staging_add_dev_domain(struct platform_device *pdev,
+ const char *domain)
+{
+ return 0;
+}
+#endif
+
int __init board_staging_register_device(const struct board_staging_dev *dev)
{
struct platform_device *pdev = dev->pdev;
@@ -161,7 +195,7 @@ int __init board_staging_register_device(const struct board_staging_dev *dev)
}
if (dev->domain)
- __pm_genpd_name_add_device(dev->domain, &pdev->dev, NULL);
+ board_staging_add_dev_domain(pdev, dev->domain);
return error;
}
--
1.9.1
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at 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
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