Differences

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--- etc:users:jcmvbkbc:linux-xtensa:esp32s3:gpio [2024/02/04 13:48] – jcmvbkbc
+++ etc:users:jcmvbkbc:linux-xtensa:esp32s3:gpio [2024/02/05 11:34] (current) – jcmvbkbc
@@ Line 20: / Line 20: @@
 These properties cannot be changed at runtime (short of writing directly to IO_MUX_n_REG registers).
-When there's no direct connection for the function in the IO MUX or the pin with direct connection cannot be used a function may be routed through the GPIO matrix to a different GPIO and connected to a different pin. These settings are controlled by the children of the nodes ''gpio_out_mux: gpio_out_mux@60004554'' and ''gpio_in_mux: gpio_in_mux@60004154''. Numbering schemes are different for output and input muxes. E.g. for the ouput mux a GPIO index is mapped to a peripheral signal (table 6.2):
+When there's no direct connection for the function in the IO MUX (e.g. UART2 signals are not there) or the pin with direct connection cannot be used, a function may be routed through the GPIO matrix to a different GPIO and connected to a different pin. These settings are controlled by the children of the nodes ''gpio_out_mux: gpio_out_mux@60004554'' and ''gpio_in_mux: gpio_in_mux@60004154''. Numbering schemes are different for output and input muxes. E.g. for the ouput mux a GPIO index is mapped to a peripheral signal (table 6.2):
 <code>
 &gpio_out_mux {
@@ Line 49: / Line 49: @@
 </code>
-Other properties of a GPIO pin (input/output, normal/open drain, interrupt type) can be controlled through the GPIO API or through the device tree connection for the pin, like the pins 6, 7 and 8 here:
+Other properties of a GPIO pin (input/output, normal/open drain, interrupt type) can be controlled through the GPIO API or through the device tree connection for the pin, like the pins 6, 7 and 8 have here:
 <code>
 i2c0 {
@@ Line 74: / Line 74: @@
 </code>
-GPIO pins that need to be in a specific state can be brought there by adding gpio-hog nodes under the gpio controller node, see [[https://github.com/jcmvbkbc/linux-xtensa/blob/v6.7/Documentation/devicetree/bindings/gpio/gpio.txt#L202|Documentation/devicetree/bindings/gpio/gpio.txt]] for the details.
+GPIO pins may need to be in a specific state after boot, but there may be no device that would drive them. In that case they can be brought to that state by the gpio-hog nodes added under the gpio controller node, see [[https://github.com/jcmvbkbc/linux-xtensa/blob/v6.7/Documentation/devicetree/bindings/gpio/gpio.txt#L202|Documentation/devicetree/bindings/gpio/gpio.txt]] for the details.