diff options
author | Stephen Boyd <sboyd@codeaurora.org> | 2015-02-06 11:42:43 -0800 |
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committer | Michael Turquette <mturquette@linaro.org> | 2015-02-06 17:53:20 -0800 |
commit | 73e0e496afdac9a5190eb3b9c51fdfebcc14ebd4 (patch) | |
tree | cb930721a52db0c402aacbdba214a0bdc31fac75 | |
parent | 5469d4f22e0c18fc5499b11269d2c528094bcf1e (diff) | |
download | op-kernel-dev-73e0e496afdac9a5190eb3b9c51fdfebcc14ebd4.zip op-kernel-dev-73e0e496afdac9a5190eb3b9c51fdfebcc14ebd4.tar.gz |
clkdev: Always allocate a struct clk and call __clk_get() w/ CCF
of_clk_get_by_clkspec() returns a struct clk pointer but it
doesn't create a new handle for the consumers when we're using
the common clock framework. Instead it just returns whatever the
clk provider hands out. When the consumers go to call clk_put()
we get an Oops.
Unable to handle kernel paging request at virtual address 00200200
pgd = c0004000
[00200200] *pgd=00000000
Internal error: Oops: 805 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.19.0-rc1-00104-ga251361a-dirty #992
Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
task: ee00b000 ti: ee088000 task.ti: ee088000
PC is at __clk_put+0x24/0xd0
LR is at clk_prepare_lock+0xc/0xec
pc : [<c03eef38>] lr : [<c03ec1f4>] psr: 20000153
sp : ee089de8 ip : 00000000 fp : 00000000
r10: ee02f480 r9 : 00000001 r8 : 00000000
r7 : ee031cc0 r6 : ee089e08 r5 : 00000000 r4 : ee02f480
r3 : 00100100 r2 : 00200200 r1 : 0000091e r0 : 00000001
Flags: nzCv IRQs on FIQs off Mode SVC_32 ISA ARM Segment kernel
Control: 10c5387d Table: 4000404a DAC: 00000015
Process swapper/0 (pid: 1, stack limit = 0xee088238)
Stack: (0xee089de8 to 0xee08a000)
9de0: ee7c8f14 c03f0ec8 ee089e08 00000000 c0718dc8 00000001
9e00: 00000000 c04ee0f0 ee7e0844 00000001 00000181 c04edb58 ee2bd320 00000000
9e20: 00000000 c011dc5c ee16a1e0 00000000 00000000 c0718dc8 ee16a1e0 ee2bd1e0
9e40: c0641740 ee16a1e0 00000000 ee2bd320 c0718dc8 ee1d3e10 ee1d3e10 00000000
9e60: c0769a88 00000000 c0718dc8 00000000 00000000 c02c3124 c02c310c ee1d3e10
9e80: c07b4eec 00000000 c0769a88 c02c1d0c ee1d3e10 c0769a88 ee1d3e44 00000000
9ea0: c07091dc c02c1eb8 00000000 c0769a88 c02c1e2c c02c0544 ee005478 ee1676c0
9ec0: c0769a88 ee3a4e80 c0760ce8 c02c150c c0669b90 c0769a88 c0746cd8 c0769a88
9ee0: c0746cd8 ee2bc4c0 c0778c00 c02c24e0 00000000 c0746cd8 c0746cd8 c07091f0
9f00: 00000000 c0008944 c04f405c 00000025 ee00b000 60000153 c074ab00 00000000
9f20: 00000000 c074ab90 60000153 00000000 ef7fca5d c050860c 000000b6 c0036b88
9f40: c065ecc4 c06bc728 00000006 00000006 c074ab30 ef7fca40 c0739bdc 00000006
9f60: c0718dbc c0778c00 000000b6 c0718dc8 c06ed598 c06edd64 00000006 00000006
9f80: c06ed598 c003b438 00000000 c04e64f4 00000000 00000000 00000000 00000000
9fa0: 00000000 c04e64fc 00000000 c000e838 00000000 00000000 00000000 00000000
9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 c0c0c0c0 c0c0c0c0
[<c03eef38>] (__clk_put) from [<c03f0ec8>] (of_clk_set_defaults+0xe0/0x2c0)
[<c03f0ec8>] (of_clk_set_defaults) from [<c02c3124>] (platform_drv_probe+0x18/0xa4)
[<c02c3124>] (platform_drv_probe) from [<c02c1d0c>] (driver_probe_device+0x10c/0x22c)
[<c02c1d0c>] (driver_probe_device) from [<c02c1eb8>] (__driver_attach+0x8c/0x90)
[<c02c1eb8>] (__driver_attach) from [<c02c0544>] (bus_for_each_dev+0x54/0x88)
[<c02c0544>] (bus_for_each_dev) from [<c02c150c>] (bus_add_driver+0xd4/0x1d0)
[<c02c150c>] (bus_add_driver) from [<c02c24e0>] (driver_register+0x78/0xf4)
[<c02c24e0>] (driver_register) from [<c07091f0>] (fimc_md_init+0x14/0x30)
[<c07091f0>] (fimc_md_init) from [<c0008944>] (do_one_initcall+0x80/0x1d0)
[<c0008944>] (do_one_initcall) from [<c06edd64>] (kernel_init_freeable+0x108/0x1d4)
[<c06edd64>] (kernel_init_freeable) from [<c04e64fc>] (kernel_init+0x8/0xec)
[<c04e64fc>] (kernel_init) from [<c000e838>] (ret_from_fork+0x14/0x3c)
Code: ebfff4ae e5943014 e5942018 e3530000 (e5823000)
Let's create a per-user handle here so that clk_put() can
properly unlink it and free the handle. Now that we allocate a
clk structure here we need to free it if __clk_get() fails so
bury the __clk_get() call in __of_clk_get_from_provider(). We
need to handle the same problem in clk_get_sys() so export
__clk_free_clk() to clkdev.c and do the same thing, except let's
use a union to make this code #ifdef free.
This fixes the above crash, properly calls __clk_get() when
of_clk_get_from_provider() is called, and cleans up the clk
structure on the error path of clk_get_sys().
Fixes: 035a61c314eb "clk: Make clk API return per-user struct clk instances"
Reported-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reported-by: Alban Browaeys <alban.browaeys@gmail.com>
Tested-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Alban Browaeys <prahal@yahoo.com>
Reviewed-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
-rw-r--r-- | drivers/clk/clk.c | 18 | ||||
-rw-r--r-- | drivers/clk/clk.h | 19 | ||||
-rw-r--r-- | drivers/clk/clkdev.c | 59 |
3 files changed, 59 insertions, 37 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 1134560..5469d77 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -2382,7 +2382,7 @@ struct clk *__clk_create_clk(struct clk_hw *hw, const char *dev_id, return clk; } -static void __clk_free_clk(struct clk *clk) +void __clk_free_clk(struct clk *clk) { clk_prepare_lock(); hlist_del(&clk->child_node); @@ -2894,7 +2894,8 @@ void of_clk_del_provider(struct device_node *np) } EXPORT_SYMBOL_GPL(of_clk_del_provider); -struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec) +struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec, + const char *dev_id, const char *con_id) { struct of_clk_provider *provider; struct clk *clk = ERR_PTR(-EPROBE_DEFER); @@ -2903,8 +2904,17 @@ struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec) list_for_each_entry(provider, &of_clk_providers, link) { if (provider->node == clkspec->np) clk = provider->get(clkspec, provider->data); - if (!IS_ERR(clk)) + if (!IS_ERR(clk)) { + clk = __clk_create_clk(__clk_get_hw(clk), dev_id, + con_id); + + if (!IS_ERR(clk) && !__clk_get(clk)) { + __clk_free_clk(clk); + clk = ERR_PTR(-ENOENT); + } + break; + } } return clk; @@ -2915,7 +2925,7 @@ struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec) struct clk *clk; mutex_lock(&of_clk_mutex); - clk = __of_clk_get_from_provider(clkspec); + clk = __of_clk_get_from_provider(clkspec, NULL, __func__); mutex_unlock(&of_clk_mutex); return clk; diff --git a/drivers/clk/clk.h b/drivers/clk/clk.h index 23c44e5..ba84540 100644 --- a/drivers/clk/clk.h +++ b/drivers/clk/clk.h @@ -13,10 +13,27 @@ struct clk_hw; #if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK) struct clk *of_clk_get_by_clkspec(struct of_phandle_args *clkspec); -struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec); +struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec, + const char *dev_id, const char *con_id); void of_clk_lock(void); void of_clk_unlock(void); #endif +#ifdef CONFIG_COMMON_CLK struct clk *__clk_create_clk(struct clk_hw *hw, const char *dev_id, const char *con_id); +void __clk_free_clk(struct clk *clk); +#else +/* All these casts to avoid ifdefs in clkdev... */ +static inline struct clk * +__clk_create_clk(struct clk_hw *hw, const char *dev_id, const char *con_id) +{ + return (struct clk *)hw; +} +static inline void __clk_free_clk(struct clk *clk) { } +static struct clk_hw *__clk_get_hw(struct clk *clk) +{ + return (struct clk_hw *)clk; +} + +#endif diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c index 29a1ab7..043fd36 100644 --- a/drivers/clk/clkdev.c +++ b/drivers/clk/clkdev.c @@ -29,6 +29,20 @@ static DEFINE_MUTEX(clocks_mutex); #if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK) +static struct clk *__of_clk_get_by_clkspec(struct of_phandle_args *clkspec, + const char *dev_id, const char *con_id) +{ + struct clk *clk; + + if (!clkspec) + return ERR_PTR(-EINVAL); + + of_clk_lock(); + clk = __of_clk_get_from_provider(clkspec, dev_id, con_id); + of_clk_unlock(); + return clk; +} + /** * of_clk_get_by_clkspec() - Lookup a clock form a clock provider * @clkspec: pointer to a clock specifier data structure @@ -39,22 +53,11 @@ static DEFINE_MUTEX(clocks_mutex); */ struct clk *of_clk_get_by_clkspec(struct of_phandle_args *clkspec) { - struct clk *clk; - - if (!clkspec) - return ERR_PTR(-EINVAL); - - of_clk_lock(); - clk = __of_clk_get_from_provider(clkspec); - - if (!IS_ERR(clk) && !__clk_get(clk)) - clk = ERR_PTR(-ENOENT); - - of_clk_unlock(); - return clk; + return __of_clk_get_by_clkspec(clkspec, NULL, __func__); } -static struct clk *__of_clk_get(struct device_node *np, int index) +static struct clk *__of_clk_get(struct device_node *np, int index, + const char *dev_id, const char *con_id) { struct of_phandle_args clkspec; struct clk *clk; @@ -68,7 +71,7 @@ static struct clk *__of_clk_get(struct device_node *np, int index) if (rc) return ERR_PTR(rc); - clk = of_clk_get_by_clkspec(&clkspec); + clk = __of_clk_get_by_clkspec(&clkspec, dev_id, con_id); of_node_put(clkspec.np); return clk; @@ -76,12 +79,7 @@ static struct clk *__of_clk_get(struct device_node *np, int index) struct clk *of_clk_get(struct device_node *np, int index) { - struct clk *clk = __of_clk_get(np, index); - - if (!IS_ERR(clk)) - clk = __clk_create_clk(__clk_get_hw(clk), np->full_name, NULL); - - return clk; + return __of_clk_get(np, index, np->full_name, NULL); } EXPORT_SYMBOL(of_clk_get); @@ -102,12 +100,10 @@ static struct clk *__of_clk_get_by_name(struct device_node *np, */ if (name) index = of_property_match_string(np, "clock-names", name); - clk = __of_clk_get(np, index); + clk = __of_clk_get(np, index, dev_id, name); if (!IS_ERR(clk)) { - clk = __clk_create_clk(__clk_get_hw(clk), dev_id, name); break; - } - else if (name && index >= 0) { + } else if (name && index >= 0) { if (PTR_ERR(clk) != -EPROBE_DEFER) pr_err("ERROR: could not get clock %s:%s(%i)\n", np->full_name, name ? name : "", index); @@ -209,17 +205,16 @@ struct clk *clk_get_sys(const char *dev_id, const char *con_id) if (!cl) goto out; - if (!__clk_get(cl->clk)) { + clk = __clk_create_clk(__clk_get_hw(cl->clk), dev_id, con_id); + if (IS_ERR(clk)) + goto out; + + if (!__clk_get(clk)) { + __clk_free_clk(clk); cl = NULL; goto out; } -#if defined(CONFIG_COMMON_CLK) - clk = __clk_create_clk(__clk_get_hw(cl->clk), dev_id, con_id); -#else - clk = cl->clk; -#endif - out: mutex_unlock(&clocks_mutex); |