What the patch does:
1. Call pinmux_disable_setting ahead of pinmux_enable_setting
each time pinctrl_select_state is called
2. Remove the HW disable operation in pinmux_disable_setting function.
3. Remove the disable ops in struct pinmux_ops
4. Remove all the disable ops users in current code base.
Notes:
1. Great thanks for the suggestion from Linus, Tony Lindgren and
Stephen Warren and Everyone that shared comments on this patch.
2. The patch also includes comment fixes from Stephen Warren.
The reason why we do this:
1. To avoid duplicated calling of the enable_setting operation
without disabling operation inbetween which will let the pin
descriptor desc->mux_usecount increase monotonously.
2. The HW pin disable operation is not useful for any of the
existing platforms.
And this can be used to avoid the HW glitch after using the
item #1 modification.
In the following case, the issue can be reproduced:
1. There is a driver that need to switch pin state dynamically,
e.g. between "sleep" and "default" state
2. The pin setting configuration in a DTS node may be like this:
component a {
pinctrl-names = "default", "sleep";
pinctrl-0 = <&a_grp_setting &c_grp_setting>;
pinctrl-1 = <&b_grp_setting &c_grp_setting>;
}
The "c_grp_setting" config node is totally identical, maybe like
following one:
c_grp_setting: c_grp_setting {
pinctrl-single,pins = <GPIO48 AF6>;
}
3. When switching the pin state in the following official pinctrl
sequence:
pin = pinctrl_get();
state = pinctrl_lookup_state(wanted_state);
pinctrl_select_state(state);
pinctrl_put();
Test Result:
1. The switch is completed as expected, that is: the device's
pin configuration is changed according to the description in the
"wanted_state" group setting
2. The "desc->mux_usecount" of the corresponding pins in "c_group"
is increased without being decreased, because the "desc" is for
each physical pin while the setting is for each setting node
in the DTS.
Thus, if the "c_grp_setting" in pinctrl-0 is not disabled ahead
of enabling "c_grp_setting" in pinctrl-1, the desc->mux_usecount
will keep increasing without any chance to be decreased.
According to the comments in the original code, only the setting,
in old state but not in new state, will be "disabled" (calling
pinmux_disable_setting), which is correct logic but not intact. We
still need consider case that the setting is in both old state
and new state. We can do this in the following two ways:
1. Avoid to "enable"(calling pinmux_enable_setting) the "same pin
setting" repeatedly
2. "Disable"(calling pinmux_disable_setting) the "same pin setting",
actually two setting instances, ahead of enabling them.
Analysis:
1. The solution #2 is better because it can avoid too much
iteration.
2. If we disable all of the settings in the old state and one of
the setting(s) exist in the new state, the pins mux function
change may happen when some SoC vendors defined the
"pinctrl-single,function-off"
in their DTS file.
old_setting => disabled_setting => new_setting.
3. In the pinmux framework, when a pin state is switched, the
setting in the old state should be marked as "disabled".
Conclusion:
1. To Remove the HW disabling operation to above the glitch mentioned
above.
2. Handle the issue mentioned above by disabling all of the settings
in old state and then enable the all of the settings in new state.
Signed-off-by: Fan Wu <fwu@marvell.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Maxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Current code only touches the direction register when setting direction
to output, which breaks logic like
echo high > /sys/class/gpio/gpio0/direction
which is expected to also set the value. This patch also adds a call
to update the value register when setting direction to output.
Signed-off-by: Alexey Charkov <alchark@gmail.com>
Acked-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Due to an assumption in the VT8500 pinctrl driver, the value passed
from devicetree for 'wm,pull' was not explicitly translated before
being passed to pinconf.
Since v3.10, changes to 'enum pin_config_param', PIN_CONFIG_BIAS_PULL_(UP/DOWN)
no longer map 1-to-1 with the expected values in devicetree.
This patch adds a small translation between the devicetree values (0..2)
and the enum pin_config_param equivalent values.
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This switches the two members of struct gpio_chip that were
defined as unsigned foo:1 to bool, because that is indeed what
they are. Switch all users in the gpio and pinctrl subsystems
to assign these values with true/false instead of 0/1. The
users outside these subsystems will survive since true/false
is 1/0, atleast we set some kind of more strict typing example.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
When setting pin configuration in the pinctrl framework, pin_config_set() or
pin_config_group_set() is called in a loop to set one configuration at a time
for the specified pin or group.
This patch 1) removes the loop and 2) changes the API to pass the whole pin
config array to the driver. It is now up to the driver to loop through the
configs. This allows the driver to potentially combine configs and reduce the
number of writes to pin config registers.
All c files changed have been build-tested to verify the change compiles and
that the corresponding .o is successfully generated.
Signed-off-by: Sherman Yin <syin@broadcom.com>
Reviewed-by: Christian Daudt <csd@broadcom.com>
Reviewed-by: Matt Porter <matt.porter@linaro.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
There is a error message within devm_ioremap_resource
already, so remove the dev_err call to avoid redundant
error message.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Replace a call to deprecated devm_request_and_ioremap by devm_ioremap_resource.
Found with coccicheck and this semantic patch:
scripts/coccinelle/api/devm_ioremap_resource.cocci
Signed-off-by: Laurent Navet <laurent.navet@gmail.com>
Acked-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Otherwise, we return 0 in probe error paths when gpiochip_remove() returns 0.
Also show error message if gpiochip_remove() fails.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Tony Prisk <linux@prisktech.co.nz>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
WMT_PIN_WAKEUP1 should be declared as WMT_PIN(0, 17) rather than
WMT_PIN(0, 16). This currently generates a runtime warning because
WMT_PIN_WAKEUP0 is already defined as WMT_PIN(0, 16).
Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
pinctrl_register() returns NULL on error.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Tony Prisk <linux@prisktech.co.nz>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
This patch adds support for the GPIO/pinmux controller found on the VIA
VT8500 and Wondermedia WM8xxx-series SoCs.
Each pin within the controller is capable of operating as a GPIO or as
an alternate function. The pins are numbered according to their control
bank/bit so that if new pins are added, the existing numbering is maintained.
All currently supported SoCs are included: VT8500, WM8505, WM8650, WM8750 and
WM8850.
Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
