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  1. 05 2月, 2013 2 次提交
  3. 31 1月, 2013 3 次提交
  5. 30 1月, 2013 1 次提交
  7. 23 1月, 2013 1 次提交
    • L
      drivers/pinctrl: grab default handles from device core · ab78029e
      由 Linus Walleij 提交于 
      This makes the device core auto-grab the pinctrl handle and set
the "default" (PINCTRL_STATE_DEFAULT) state for every device
that is present in the device model right before probe. This will
account for the lion's share of embedded silicon devcies.

A modification of the semantics for pinctrl_get() is also done:
previously if the pinctrl handle for a certain device was already
taken, the pinctrl core would return an error. Now, since the
core may have already default-grabbed the handle and set its
state to "default", if the handle was already taken, this will
be disregarded and the located, previously instanitated handle
will be returned to the caller.

This way all code in drivers explicitly requesting their pinctrl
handlers will still be functional, and drivers that want to
explicitly retrieve and switch their handles can still do that.
But if the desired functionality is just boilerplate of this
type in the probe() function:

struct pinctrl  *p;

p = devm_pinctrl_get_select_default(&dev);
if (IS_ERR(p)) {
   if (PTR_ERR(p) == -EPROBE_DEFER)
        return -EPROBE_DEFER;
        dev_warn(&dev, "no pinctrl handle\n");
}

The discussion began with the addition of such boilerplate
to the omap4 keypad driver:
http://marc.info/?l=linux-input&m=135091157719300&w=2

A previous approach using notifiers was discussed:
http://marc.info/?l=linux-kernel&m=135263661110528&w=2
This failed because it could not handle deferred probes.

This patch alone does not solve the entire dilemma faced:
whether code should be distributed into the drivers or
if it should be centralized to e.g. a PM domain. But it
solves the immediate issue of the addition of boilerplate
to a lot of drivers that just want to grab the default
state. As mentioned, they can later explicitly retrieve
the handle and set different states, and this could as
well be done by e.g. PM domains as it is only related
to a certain struct device * pointer.

ChangeLog v4->v5 (Stephen):
- Simplified the devicecore grab code.
- Deleted a piece of documentation recommending that pins
  be mapped to a device rather than hogged.
ChangeLog v3->v4 (Linus):
- Drop overzealous NULL checks.
- Move kref initialization to pinctrl_create().
- Seeking Tested-by from Stephen Warren so we do not disturb
  the Tegra platform.
- Seeking ACK on this from Greg (and others who like it) so I
  can merge it through the pinctrl subsystem.
ChangeLog v2->v3 (Linus):
- Abstain from using IS_ERR_OR_NULL() in the driver core,
  Russell recently sent a patch to remove it. Handle the
  NULL case explicitly even though it's a bogus case.
- Make sure we handle probe deferral correctly in the device
  core file. devm_kfree() the container on error so we don't
  waste memory for devices without pinctrl handles.
- Introduce reference counting into the pinctrl core using
  <linux/kref.h> so that we don't release pinctrl handles
  that have been obtained for two or more places.
ChangeLog v1->v2 (Linus):
- Only store a pointer in the device struct, and only allocate
  this if it's really used by the device.

Cc: Felipe Balbi <balbi@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Mitch Bradley <wmb@firmworks.com>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Rickard Andersson <rickard.andersson@stericsson.com>
Cc: Russell King <linux@arm.linux.org.uk>
Reviewed-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
[swarren: fixed and simplified error-handling in pinctrl_bind_pins(), to
correctly handle deferred probe. Removed admonition from docs not to use
pinctrl hogs for devices]
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
      ab78029e
  9. 21 1月, 2013 3 次提交
  11. 19 1月, 2013 2 次提交
    • L
      pinctrl: nomadik: Allow prcm_base to be extracted from Device Tree · 32e67eee
      由 Lee Jones 提交于 
      The Nomadik Pinctrl driver requires access to some PRCMU registers
in order to run with full functionality. When Device Tree is
disabled the required PRCMU base address is passed in via platform
data, so in order for Device Tree booting to be as functional, we
need a similar mechanism to fetch it from Device Tree.

The new semantics goes like this: Parse the Device Tree and look
for the PRCMU node using a provided Phandle. Obtain the ioremaped
address from that node. If one was supplied via platform data
over-write it with anything found in Device Tree. Fail if either
the prcm_base can't be found if we're running on anything other
than an STN8815 ASIC.
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
      32e67eee
    • K
      pinctrl: exynos: change PINCTRL_EXYNOS option · 7452b64d
      由 Kukjin Kim 提交于 
      Since pinctrl-exynos can support exynos4 and exynos5 so changed
the option name to PINCTRL_EXYNOS for more clarity.

Cc: Thomas Abraham <Thomas.abraham@linaro.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
      7452b64d
  13. 18 1月, 2013 2 次提交
  15. 12 1月, 2013 8 次提交
  17. 08 1月, 2013 7 次提交
  19. 07 1月, 2013 7 次提交
  21. 06 1月, 2013 2 次提交
  23. 05 1月, 2013 2 次提交