ARM: OMAP2+: hwmod: Fix usage of invalid iclk / oclk when clock node is not present
authorNishanth Menon <nm@ti.com>
Mon, 9 Dec 2013 01:39:03 +0000 (18:39 -0700)
committerPaul Walmsley <paul@pwsan.com>
Mon, 9 Dec 2013 18:51:30 +0000 (11:51 -0700)
commit0e7dc862cf687234ed1b01a6b2461b782ea0bca0
tree348515464ac254197a68bc61e7b19f47d6d7b41d
parent7f4d3641e2548d1ac5dee837ff434df668a2810c
ARM: OMAP2+: hwmod: Fix usage of invalid iclk / oclk when clock node is not present

commit dc75925d(OMAP: hwmod: Fix the missing braces) introduced
missing braces, however, we just set return result if clk_get fail
and we populate the error pointer in clk pointer and pass it along to
clk_prepare. This is wrong. The intent seems to be retry remaining
clocks if they are available and warn the ones we cant find clks for.

With the current logic, we see the following crash:
omap_hwmod: l3_main: cannot clk_get interface_clk emac_ick
Unable to handle kernel NULL pointer dereference at virtual address 00000032
pgd = c0004000
[00000032] *pgd=00000000
Internal error: Oops: 5 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.13.0-rc1-00044-gcc9fd5a-dirty #19
task: ce0c3440 ti: ce0c4000 task.ti: ce0c4000
PC is at __clk_prepare+0x10/0x74
LR is at clk_prepare+0x14/0x24
  <snip>
[<c044d59c>] (__clk_prepare+0x10/0x74) from [<c044d9b0>] (clk_prepare+0x14/0x24)
[<c044d9b0>] (clk_prepare+0x14/0x24) from [<c077d8c4>] (_init+0x24c/0x3bc)
[<c077d8c4>] (_init+0x24c/0x3bc) from [<c0027328>] (omap_hwmod_for_each+0x34/0x5c)
[<c0027328>] (omap_hwmod_for_each+0x34/0x5c) from [<c077dfa0>] (__omap_hwmod_setup_all+0x24/0x40)
[<c077dfa0>] (__omap_hwmod_setup_all+0x24/0x40) from [<c0008928>] (do_one_initcall+0x38/0x168)
[<c0008928>] (do_one_initcall+0x38/0x168) from [<c0771be8>] (kernel_init_freeable+0xfc/0x1cc)
[<c0771be8>] (kernel_init_freeable+0xfc/0x1cc) from [<c0521064>] (kernel_init+0x8/0x110)
[<c0521064>] (kernel_init+0x8/0x110) from [<c000e568>] (ret_from_fork+0x14/0x2c)
Code: e92d4038 e2504000 01a05004 0a000005 (e5943034)

So, just warn and continue instead of proceeding and crashing, with
missing clock nodes/bad data, we will eventually fail, however we
should now have enough information to identify the culprit.

Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
arch/arm/mach-omap2/omap_hwmod.c