Re: [PATCH v2 08/12] soc: mediatek: pm-domains: Add subsystem clocks

From: Matthias Brugger
Date: Fri Oct 02 2020 - 05:04:55 EST




On 01/10/2020 18:01, Enric Balletbo i Serra wrote:
From: Matthias Brugger <mbrugger@xxxxxxxx>

For the bus protection operations, some subsystem clocks need to be enabled
before releasing the protection. This patch identifies the subsystem clocks
by it's name.

Suggested-by: Weiyi Lu <weiyi.lu@xxxxxxxxxxxx>
[Adapted the patch to the mtk-pm-domains driver]
Signed-off-by: Matthias Brugger <mbrugger@xxxxxxxx>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
---

Changes in v2:
- Use dev_err_probe if getting clocks fails, so an error is not printed
if is deferred.

drivers/soc/mediatek/mtk-pm-domains.c | 89 ++++++++++++++++++++++-----
1 file changed, 75 insertions(+), 14 deletions(-)

diff --git a/drivers/soc/mediatek/mtk-pm-domains.c b/drivers/soc/mediatek/mtk-pm-domains.c
index e0a52d489fea..2075072f16da 100644
--- a/drivers/soc/mediatek/mtk-pm-domains.c
+++ b/drivers/soc/mediatek/mtk-pm-domains.c
[...]
+ for (i = 0; i < pd->num_subsys_clks; i++) {
+ struct clk *clk = of_clk_get(node, i + clk_ind);
+
+ if (IS_ERR(clk)) {
+ ret = PTR_ERR(clk);
+ dev_err_probe(scpsys->dev, PTR_ERR(clk),
+ "%pOFn: failed to get clk at index %d: %d\n",
+ node, i + clk_ind, ret);
+ goto err_put_subsys_clocks;
+ }
+
+ pd->subsys_clks[i].clk = clk;
+ }
+
+ ret = clk_bulk_prepare(pd->num_subsys_clks, pd->subsys_clks);
+ if (ret)
+ goto err_put_subsys_clocks;
+

Not sure if it really matters, but logically we should prepare the basic clocks before we prepare the subsystem clocks. And fix the error handling accordingly.

Regards,
Matthias

ret = clk_bulk_prepare(pd->num_clks, pd->clks);
if (ret)
- goto err_put_clocks;
+ goto err_unprepare_subsys_clocks;
/*
* Initially turn on all domains to make the domains usable
@@ -462,6 +513,12 @@ static int scpsys_add_one_domain(struct scpsys *scpsys, struct device_node *node
err_unprepare_clocks:
clk_bulk_unprepare(pd->num_clks, pd->clks);
+err_unprepare_subsys_clocks:
+ clk_bulk_unprepare(pd->num_subsys_clks, pd->subsys_clks);
+err_put_subsys_clocks:
+ clk_bulk_put(pd->num_subsys_clks, pd->subsys_clks);
+ devm_kfree(scpsys->dev, pd->subsys_clks);
+ pd->num_subsys_clks = 0;
err_put_clocks:
clk_bulk_put(pd->num_clks, pd->clks);
devm_kfree(scpsys->dev, pd->clks);
@@ -541,6 +598,10 @@ static void scpsys_remove_one_domain(struct scpsys_domain *pd)
clk_bulk_unprepare(pd->num_clks, pd->clks);
clk_bulk_put(pd->num_clks, pd->clks);
pd->num_clks = 0;
+
+ clk_bulk_unprepare(pd->num_subsys_clks, pd->subsys_clks);
+ clk_bulk_put(pd->num_subsys_clks, pd->subsys_clks);
+ pd->num_subsys_clks = 0;
}
static void scpsys_domain_cleanup(struct scpsys *scpsys)