1 // SPDX-License-Identifier: GPL-2.0
3  * Copyright (C) 2017-2025 Arm Ltd.
5  * Generic DT driven Allwinner pinctrl driver routines.
6  * Builds the pin tables from minimal driver information and pin groups
8  * sunxi pinctrl driver.
10  * out in a per-SoC .c file. This code generates this table, like so:
13  *				// pin, based on pins_per_bank[] array passed in
15  *    SUNXI_FUNCTION(0x0, "gpio_in"),	// always added, for every pin
16  *    SUNXI_FUNCTION(0x1, "gpio_out"),	// always added, for every pin
19  *				//   mmc0-pins {
25  *						// array passed in
32 #include <linux/pinctrl/pinctrl.h>
36 #include "pinctrl-sunxi.h"
57 		index = num_elems - 1;  in sunxi_pinctrl_dt_read_pinmux()
68  * Allocate a table with a sunxi_desc_pin structure for every pin needed.
69  * Fills in the respective pin names ("PA0") and their pin numbers.
70  * Returns the pins array. We cannot use the member in *desc yet, as this
71  * is marked as const, and we will need to change the array still.
79 	int port_base = desc->pin_base / PINS_PER_BANK;  in init_pins_table()
85 	 * Also work out how much memory we need to store all the pin names.  in init_pins_table()
88 		desc->npins += pins_per_bank[i];  in init_pins_table()
97 			name_size += (pins_per_bank[i] - 10) * 5;  in init_pins_table()
101 	if (desc->npins == 0) {  in init_pins_table()
103 		return ERR_PTR(-EINVAL);  in init_pins_table()
106 	pins = devm_kzalloc(dev, desc->npins * sizeof(*pins), GFP_KERNEL);  in init_pins_table()
108 		return ERR_PTR(-ENOMEM);  in init_pins_table()
110 	/* Allocate memory to store the name for every pin. */  in init_pins_table()
113 		return ERR_PTR(-ENOMEM);  in init_pins_table()
115 	/* Fill the pins array with the name and the number for each pin. */  in init_pins_table()
123 			cur_pin->pin.number = (port_base + i) * PINS_PER_BANK + j;  in init_pins_table()
124 			cur_pin->pin.name = cur_name;  in init_pins_table()
133  * Work out the number of functions for each pin. This will visit every
134  * child node of the pinctrl DT node to find all advertised functions.
135  * Provide memory to hold the per-function information and assign it to
136  * the pin table.
137  * Fill in the GPIO in/out functions already (that every pin has), also add
138  * an "irq" function at the end, for those pins in IRQ-capable ports.
140  * We (ab)use the "variant" member in each pin to keep track of the number of
154 	 * We need at least three functions per pin:  in prepare_function_table()
155 	 * - one for GPIO in  in prepare_function_table()
156 	 * - one for GPIO out  in prepare_function_table()
157 	 * - one for the sentinel signalling the end of the list  in prepare_function_table()
162 	 * Add a function for each pin in a bank supporting interrupts.  in prepare_function_table()
164 	 * functions per pin. This will be cleaned back to 0 before we hand  in prepare_function_table()
165 	 * over the whole structure to the generic sunxi pinctrl setup code.  in prepare_function_table()
168 		struct sunxi_desc_pin *pin = &pins[i];  in prepare_function_table()  local
169 		int bank = pin->pin.number / PINS_PER_BANK;  in prepare_function_table()
172 			pin->variant++;  in prepare_function_table()
178 	 * Go over each pin group (every child of the pinctrl DT node) and  in prepare_function_table()
188 				if (strcmp(pins[i].pin.name, name))  in prepare_function_table()
200 	 * We later use pointers into this table to mark each pin.  in prepare_function_table()
204 		return -ENOMEM;  in prepare_function_table()
213 		struct sunxi_desc_pin *pin = &pins[i];  in prepare_function_table()  local
214 		int bank = pin->pin.number / PINS_PER_BANK;  in prepare_function_table()
215 		int lastfunc = pin->variant + 1;  in prepare_function_table()
228 			func[lastfunc].irqnum = pin->pin.number % PINS_PER_BANK;  in prepare_function_table()
235 		pin->functions = func;  in prepare_function_table()
238 		func += pin->variant + 3;  in prepare_function_table()
244 		pin->variant = 2;  in prepare_function_table()
252  * mux value to the respective pin.
262 	int pin, i, index;  in fill_pin_function()  local
272 		/* Find the index of this pin in our table. */  in fill_pin_function()
273 		for (pin = 0; pin < npins; pin++)  in fill_pin_function()
274 			if (!strcmp(pins[pin].pin.name, name))  in fill_pin_function()
276 		if (pin == npins) {  in fill_pin_function()
277 			dev_warn(dev, "%s: cannot find pin %s\n",  in fill_pin_function()
286 			dev_warn(dev, "%s: invalid mux value for pin %s\n",  in fill_pin_function()
293 		 * Check for double definitions by comparing the to-be-added  in fill_pin_function()
298 		for (i = 2; i < pins[pin].variant; i++) {  in fill_pin_function()
299 			func = &pins[pin].functions[i];  in fill_pin_function()
302 			if (strcmp(func->name, funcname) &&  in fill_pin_function()
303 			    func->muxval != muxval)  in fill_pin_function()
307 			if (!strcmp(func->name, funcname) &&  in fill_pin_function()
308 			    muxval == func->muxval)  in fill_pin_function()
312 				 "pin %s: function %s redefined to mux %d\n",  in fill_pin_function()
318 		if (i < pins[pin].variant) {  in fill_pin_function()
324 		func = &pins[pin].functions[pins[pin].variant];  in fill_pin_function()
325 		func->muxval = muxval;  in fill_pin_function()
326 		func->name = funcname;  in fill_pin_function()
328 		pins[pin].variant++;  in fill_pin_function()
334  * Initialise the pinctrl table, by building it from driver provided
337  * Then iterate over all pinctrl DT node children to enter the function name
338  * and mux values for each mentioned pin.
339  * At the end hand over this structure to the actual sunxi pinctrl driver.
347 	struct device_node *pnode = pdev->dev.of_node, *node;  in sunxi_pinctrl_dt_table_init()
351 	pins = init_pins_table(&pdev->dev, pins_per_bank, desc);  in sunxi_pinctrl_dt_table_init()
355 	ret = prepare_function_table(&pdev->dev, pnode, pins, desc->npins,  in sunxi_pinctrl_dt_table_init()
362 	 * and mux values to each pin listed within.  in sunxi_pinctrl_dt_table_init()
365 		fill_pin_function(&pdev->dev, node, pins, desc->npins);  in sunxi_pinctrl_dt_table_init()
368 	for (i = 0; i < desc->npins; i++)  in sunxi_pinctrl_dt_table_init()
371 	desc->pins = pins;  in sunxi_pinctrl_dt_table_init()