Since commit b36b7b72 ("mfd: syscon: clock peripheral if specified in
device tree"), we now clock syscons during access if the device tree nodes
indicate a clocks property. We haven't been doing this for
syscon_base_lookup_by_phandle though, because we did this as part of the
regmap access functions.
The best way forward is probably dropping the syscon_base API altogether
and change users to the regmap API instead, but for now, make the behavior
consistent, by detaching the clock and enabling it permanently, so:
- We are safe from breakage that results from upstream device trees moving
a clocks property from the consumer to the syscon provider (like in [1])
- Another syscon consumer can't disable the clock for a syscon that's
also shared via a syscon_base_lookup_by_phandle
I've reviewed the current driver code users of syscon_base_lookup_by_phandle
and all upstream device trees that match against the drivers lack
a clocks property, so this shouldn't alter behavior (for now).
[1]: c9322d4fe ("net: designware: eqos: stm32: drop no longer needed syscfg-clk")
Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
---
drivers/base/regmap/regmap-mmio.c | 5 ++++-
drivers/mfd/syscon.c | 4 ++++
include/regmap.h | 2 +-
3 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/base/regmap/regmap-mmio.c b/drivers/base/regmap/regmap-mmio.c
index 7ca95d6bea79..626c6fa3f387 100644
--- a/drivers/base/regmap/regmap-mmio.c
+++ b/drivers/base/regmap/regmap-mmio.c
@@ -308,9 +308,12 @@ int regmap_mmio_attach_clk(struct regmap *map, struct clk *clk)
return 0;
}
-void regmap_mmio_detach_clk(struct regmap *map)
+struct clk *regmap_mmio_detach_clk(struct regmap *map)
{
struct regmap_mmio_context *ctx = map->bus_context;
+ struct clk *clk = ctx->clk;
ctx->clk = NULL;
+
+ return clk;
}
diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index 67e2ebb6c2f5..ba0489bf95a8 100644
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -128,10 +128,14 @@ static struct syscon *node_to_syscon(struct device_node *np)
static void __iomem *syscon_node_to_base(struct device_node *np)
{
struct syscon *syscon = node_to_syscon(np);
+ struct clk *clk;
if (IS_ERR(syscon))
return ERR_CAST(syscon);
+ clk = regmap_mmio_detach_clk(syscon->regmap);
+ clk_enable(clk);
+
return syscon->base;
}
diff --git a/include/regmap.h b/include/regmap.h
index 4172c00bd2da..d950971b7d48 100644
--- a/include/regmap.h
+++ b/include/regmap.h
@@ -91,7 +91,7 @@ struct regmap *regmap_init_mmio_clk(struct device_d *dev, const char *clk_id,
int regmap_mmio_attach_clk(struct regmap *map, struct clk *clk);
-void regmap_mmio_detach_clk(struct regmap *map);
+struct clk *regmap_mmio_detach_clk(struct regmap *map);
void regmap_exit(struct regmap *map);
--
2.26.0.rc2
_______________________________________________
barebox mailing list
barebox@xxxxxxxxxxxxxxxxxxx
http://lists.infradead.org/mailman/listinfo/barebox
