diff options
| author |   José Pekkarinen <jose.pekkarinen@nokia.com> | 2016-04-11 10:41:07 +0300 |
|---|---|---|
| committer | José Pekkarinen <jose.pekkarinen@nokia.com> | 2016-04-13 08:17:18 +0300 |
| commit | e09b41010ba33a20a87472ee821fa407a5b8da36 (patch) | |
| tree | d10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/Documentation/pinctrl.txt | |
| parent | f93b97fd65072de626c074dbe099a1fff05ce060 (diff) | |
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page.
During the rebasing, the following patch collided:
Force tick interrupt and get rid of softirq magic(I70131fb85).
Collisions have been removed because its logic was found on the
source already.
Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/Documentation/pinctrl.txt')
| -rw-r--r-- | kernel/Documentation/pinctrl.txt | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/kernel/Documentation/pinctrl.txt b/kernel/Documentation/pinctrl.txt index a9b47163b..4976389e4 100644 --- a/kernel/Documentation/pinctrl.txt +++ b/kernel/Documentation/pinctrl.txt @@ -714,6 +714,7 @@ static struct pinmux_ops foo_pmxops = { .get_function_name = foo_get_fname, .get_function_groups = foo_get_groups, .set_mux = foo_set_mux, + .strict = true, }; /* Pinmux operations are handled by some pin controller */ @@ -830,6 +831,11 @@ separate memory range only intended for GPIO driving, and the register range dealing with pin config and pin multiplexing get placed into a different memory range and a separate section of the data sheet. +A flag "strict" in struct pinctrl_desc is available to check and deny +simultaneous access to the same pin from GPIO and pin multiplexing +consumers on hardware of this type. The pinctrl driver should set this flag +accordingly. + (B) pin config @@ -850,6 +856,11 @@ possible that the GPIO, pin config and pin multiplex registers are placed into the same memory range and the same section of the data sheet, although that need not be the case. +In some pin controllers, although the physical pins are designed in the same +way as (B), the GPIO function still can't be enabled at the same time as the +peripheral functions. So again the "strict" flag should be set, denying +simultaneous activation by GPIO and other muxed in devices. + From a kernel point of view, however, these are different aspects of the hardware and shall be put into different subsystems: |