linux/Documentation/devicetree/bindings/pinctrl/qcom,msm8974-pinctrl.txt
Christian Lamparter c1e802f68c dt-bindings: pinctrl: qcom: add gpio-ranges, gpio-reserved-ranges
This patch adds the gpio-ranges and gpio-reserved-ranges property
definitions to the binding text files supported by the pinctrl-msm
driver framework.

gpio-ranges:
For DT-based platforms the pinctrl-msm framework currently relies
on the deprecated-for-DT gpiochip_add_pin_range() function to add
the range of GPIOs to be handled by the pin controller. Due to
interactions within gpiolib code, this causes the pinctrl-msm
driver to bail out (-517) during boot when a gpio-hog is declared.
This can be fatal and cause the system to not boot or reset
(for a detailed explanation and call-trace, refer to patch:
"pinctrl: msm: fix gpio-hog related boot issues" in this series).

gpio-reserved-ranges:
The binding has been added as a precaution since the TrustZone
firmware (aka QSEE), which is running as the hypervisor, might
have reserved certain, but undisclosed pins. Hence reading or
writing to the registers for those pins will cause an
XPU violation and this subsequently crashes the kernel.

Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-06-28 16:28:33 +02:00

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Qualcomm MSM8974 TLMM block
Required properties:
- compatible: "qcom,msm8974-pinctrl"
- reg: Should be the base address and length of the TLMM block.
- interrupts: Should be the parent IRQ of the TLMM block.
- interrupt-controller: Marks the device node as an interrupt controller.
- #interrupt-cells: Should be two.
- gpio-controller: Marks the device node as a GPIO controller.
- #gpio-cells : Should be two.
The first cell is the gpio pin number and the
second cell is used for optional parameters.
- gpio-ranges: see ../gpio/gpio.txt
Optional properties:
- gpio-reserved-ranges: see ../gpio/gpio.txt
Please refer to ../gpio/gpio.txt and ../interrupt-controller/interrupts.txt for
a general description of GPIO and interrupt bindings.
Please refer to pinctrl-bindings.txt in this directory for details of the
common pinctrl bindings used by client devices, including the meaning of the
phrase "pin configuration node".
Qualcomm's pin configuration nodes act as a container for an arbitrary number of
subnodes. Each of these subnodes represents some desired configuration for a
pin, a group, or a list of pins or groups. This configuration can include the
mux function to select on those pin(s)/group(s), and various pin configuration
parameters, such as pull-up, drive strength, etc.
The name of each subnode is not important; all subnodes should be enumerated
and processed purely based on their content.
Each subnode only affects those parameters that are explicitly listed. In
other words, a subnode that lists a mux function but no pin configuration
parameters implies no information about any pin configuration parameters.
Similarly, a pin subnode that describes a pullup parameter implies no
information about e.g. the mux function.
The following generic properties as defined in pinctrl-bindings.txt are valid
to specify in a pin configuration subnode:
pins, function, bias-disable, bias-pull-down, bias-pull,up, drive-strength.
Non-empty subnodes must specify the 'pins' property.
Note that not all properties are valid for all pins.
Valid values for pins are:
gpio0-gpio145
Supports mux, bias and drive-strength
sdc1_clk, sdc1_cmd, sdc1_data, sdc2_clk, sdc2_cmd, sdc2_data
Supports bias and drive-strength
hsic_data, hsic_strobe
Supports only mux
Valid values for function are:
cci_i2c0, cci_i2c1, uim1, uim2, uim_batt_alarm,
blsp_uim1, blsp_uart1, blsp_i2c1, blsp_spi1,
blsp_uim2, blsp_uart2, blsp_i2c2, blsp_spi2,
blsp_uim3, blsp_uart3, blsp_i2c3, blsp_spi3,
blsp_uim4, blsp_uart4, blsp_i2c4, blsp_spi4,
blsp_uim5, blsp_uart5, blsp_i2c5, blsp_spi5,
blsp_uim6, blsp_uart6, blsp_i2c6, blsp_spi6,
blsp_uim7, blsp_uart7, blsp_i2c7, blsp_spi7,
blsp_uim8, blsp_uart8, blsp_i2c8, blsp_spi8,
blsp_uim9, blsp_uart9, blsp_i2c9, blsp_spi9,
blsp_uim10, blsp_uart10, blsp_i2c10, blsp_spi10,
blsp_uim11, blsp_uart11, blsp_i2c11, blsp_spi11,
blsp_uim12, blsp_uart12, blsp_i2c12, blsp_spi12,
blsp_spi1_cs1, blsp_spi2_cs2, blsp_spi_cs3, blsp_spi2_cs1, blsp_spi2_cs2
blsp_spi2_cs3, blsp_spi10_cs1, blsp_spi10_cs2, blsp_spi10_cs3,
sdc3, sdc4, gcc_gp_clk1, gcc_gp_clk2, gcc_gp_clk3, cci_timer0, cci_timer1,
cci_timer2, cci_timer3, cci_async_in0, cci_async_in1, cci_async_in2,
cam_mckl0, cam_mclk1, cam_mclk2, cam_mclk3, mdp_vsync, hdmi_cec, hdmi_ddc,
hdmi_hpd, edp_hpd, gp_pdm0, gp_pdm1, gp_pdm2, gp_pdm3, gp0_clk, gp1_clk,
gp_mn, tsif1, tsif2, hsic, grfc, audio_ref_clk, qua_mi2s, pri_mi2s, spkr_mi2s,
ter_mi2s, sec_mi2s, bt, fm, wlan, slimbus, hsic_ctl, gpio
(Note that this is not yet the complete list of functions)
Example:
msmgpio: pinctrl@fd510000 {
compatible = "qcom,msm8974-pinctrl";
reg = <0xfd510000 0x4000>;
gpio-controller;
#gpio-cells = <2>;
gpio-ranges = <&msmgpio 0 0 146>;
interrupt-controller;
#interrupt-cells = <2>;
interrupts = <0 208 0>;
pinctrl-names = "default";
pinctrl-0 = <&uart2_default>;
uart2_default: uart2_default {
mux {
pins = "gpio4", "gpio5";
function = "blsp_uart2";
};
tx {
pins = "gpio4";
drive-strength = <4>;
bias-disable;
};
rx {
pins = "gpio5";
drive-strength = <2>;
bias-pull-up;
};
};
};