Messages in this thread Patch in this message | | | From | Sylwester Nawrocki <> | Subject | [PATCH v3 4/5] clk: Assign module owner of a clock being registered | Date | Fri, 23 Aug 2013 17:03:46 +0200 |
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Assign module owner of a driver of a device passed to _clk_register() and __clk_register() functions so the module_{get,put} calls in __clk_get(), __clk_put() can have required effect.
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> --- Initially I had an 'owner' field added to struct clk_init_data so it can be set explicitly in clock providers. But this required modifications of all users of (devm_)clk_register() as struct clk_init_data instance was in most cases an unitialized stack variable. This would also require adding yet another argument to various clk_register_* functions registering the standard clocks. So I went for assigning clk->owner from dev->driver->owner. The disadvantages are that dereferencing dev->driver may be potentially unsafe when not holding struct device::mutex. And there might be cases where clk->owner will need to be NULL. One option is to set dev argument of clk_register_*() to NULL for that, but it predates devm_*.
Presumably a requirement could be added that callers of clk_register*() must ensure dev->driver won't change during a call to these functions ? --- drivers/clk/clk.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index c173f30..272d68d 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -1692,6 +1692,10 @@ struct clk *__clk_register(struct device *dev, struct clk_hw *hw) clk->flags = hw->init->flags; clk->parent_names = hw->init->parent_names; clk->num_parents = hw->init->num_parents; + if (dev && dev->driver) + clk->owner = dev->driver->owner; + else + clk->owner = NULL;
ret = __clk_init(dev, clk); if (ret) @@ -1712,6 +1716,8 @@ static int _clk_register(struct device *dev, struct clk_hw *hw, struct clk *clk) goto fail_name; } clk->ops = hw->init->ops; + if (dev && dev->driver) + clk->owner = dev->driver->owner; clk->hw = hw; clk->flags = hw->init->flags; clk->num_parents = hw->init->num_parents; -- 1.7.9.5
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