2 * Copyright (C) 2016 IBM Corp.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
10 #include <linux/mfd/syscon.h>
11 #include <linux/platform_device.h>
12 #include <linux/slab.h>
13 #include <linux/string.h>
15 #include "pinctrl-aspeed.h"
17 static const char *const aspeed_pinmux_ips[] = {
18 [ASPEED_IP_SCU] = "SCU",
19 [ASPEED_IP_GFX] = "GFX",
20 [ASPEED_IP_LPC] = "LPC",
23 int aspeed_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
25 struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
27 return pdata->ngroups;
30 const char *aspeed_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
33 struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
35 return pdata->groups[group].name;
38 int aspeed_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
39 unsigned int group, const unsigned int **pins,
42 struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
44 *pins = &pdata->groups[group].pins[0];
45 *npins = pdata->groups[group].npins;
50 void aspeed_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev,
51 struct seq_file *s, unsigned int offset)
53 seq_printf(s, " %s", dev_name(pctldev->dev));
56 int aspeed_pinmux_get_fn_count(struct pinctrl_dev *pctldev)
58 struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
60 return pdata->nfunctions;
63 const char *aspeed_pinmux_get_fn_name(struct pinctrl_dev *pctldev,
64 unsigned int function)
66 struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
68 return pdata->functions[function].name;
71 int aspeed_pinmux_get_fn_groups(struct pinctrl_dev *pctldev,
72 unsigned int function,
73 const char * const **groups,
74 unsigned int * const num_groups)
76 struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
78 *groups = pdata->functions[function].groups;
79 *num_groups = pdata->functions[function].ngroups;
84 static inline void aspeed_sig_desc_print_val(
85 const struct aspeed_sig_desc *desc, bool enable, u32 rv)
87 pr_debug("Want %s%X[0x%08X]=0x%X, got 0x%X from 0x%08X\n",
88 aspeed_pinmux_ips[desc->ip], desc->reg,
89 desc->mask, enable ? desc->enable : desc->disable,
90 (rv & desc->mask) >> __ffs(desc->mask), rv);
94 * Query the enabled or disabled state of a signal descriptor
96 * @desc: The signal descriptor of interest
97 * @enabled: True to query the enabled state, false to query disabled state
98 * @regmap: The IP block's regmap instance
100 * Return: 1 if the descriptor's bitfield is configured to the state
101 * selected by @enabled, 0 if not, and less than zero if an unrecoverable
104 * Evaluation of descriptor state is non-trivial in that it is not a binary
105 * outcome: The bitfields can be greater than one bit in size and thus can take
106 * a value that is neither the enabled nor disabled state recorded in the
107 * descriptor (typically this means a different function to the one of interest
108 * is enabled). Thus we must explicitly test for either condition as required.
110 static int aspeed_sig_desc_eval(const struct aspeed_sig_desc *desc,
111 bool enabled, struct regmap *map)
120 ret = regmap_read(map, desc->reg, &raw);
124 aspeed_sig_desc_print_val(desc, enabled, raw);
125 want = enabled ? desc->enable : desc->disable;
127 return ((raw & desc->mask) >> __ffs(desc->mask)) == want;
131 * Query the enabled or disabled state for a mux function's signal on a pin
133 * @expr: An expression controlling the signal for a mux function on a pin
134 * @enabled: True to query the enabled state, false to query disabled state
135 * @maps: The list of regmap instances
137 * Return: 1 if the expression composed by @enabled evaluates true, 0 if not,
138 * and less than zero if an unrecoverable failure occurred.
140 * A mux function is enabled or disabled if the function's signal expression
141 * for each pin in the function's pin group evaluates true for the desired
142 * state. An signal expression evaluates true if all of its associated signal
143 * descriptors evaluate true for the desired state.
145 * If an expression's state is described by more than one bit, either through
146 * multi-bit bitfields in a single signal descriptor or through multiple signal
147 * descriptors of a single bit then it is possible for the expression to be in
148 * neither the enabled nor disabled state. Thus we must explicitly test for
149 * either condition as required.
151 static int aspeed_sig_expr_eval(const struct aspeed_sig_expr *expr,
152 bool enabled, struct regmap * const *maps)
157 for (i = 0; i < expr->ndescs; i++) {
158 const struct aspeed_sig_desc *desc = &expr->descs[i];
160 ret = aspeed_sig_desc_eval(desc, enabled, maps[desc->ip]);
169 * Configure a pin's signal by applying an expression's descriptor state for
170 * all descriptors in the expression.
172 * @expr: The expression associated with the function whose signal is to be
174 * @enable: true to enable an function's signal through a pin's signal
175 * expression, false to disable the function's signal
176 * @maps: The list of regmap instances for pinmux register access.
178 * Return: 0 if the expression is configured as requested and a negative error
181 static int aspeed_sig_expr_set(const struct aspeed_sig_expr *expr,
182 bool enable, struct regmap * const *maps)
187 for (i = 0; i < expr->ndescs; i++) {
188 const struct aspeed_sig_desc *desc = &expr->descs[i];
189 u32 pattern = enable ? desc->enable : desc->disable;
190 u32 val = (pattern << __ffs(desc->mask));
196 * Strap registers are configured in hardware or by early-boot
197 * firmware. Treat them as read-only despite that we can write
198 * them. This may mean that certain functions cannot be
199 * deconfigured and is the reason we re-evaluate after writing
200 * all descriptor bits.
202 * Port D and port E GPIO loopback modes are the only exception
203 * as those are commonly used with front-panel buttons to allow
204 * normal operation of the host when the BMC is powered off or
205 * fails to boot. Once the BMC has booted, the loopback mode
206 * must be disabled for the BMC to control host power-on and
209 if (desc->ip == ASPEED_IP_SCU && desc->reg == HW_STRAP1 &&
210 !(desc->mask & (BIT(21) | BIT(22))))
213 if (desc->ip == ASPEED_IP_SCU && desc->reg == HW_STRAP2)
216 /* On AST2500, Set bits in SCU7C are cleared from SCU70 */
217 if (desc->ip == ASPEED_IP_SCU && desc->reg == HW_STRAP1) {
220 ret = regmap_read(maps[ASPEED_IP_SCU],
221 HW_REVISION_ID, &rev_id);
225 if (0x04 == (rev_id >> 24)) {
226 u32 value = ~val & desc->mask;
229 ret = regmap_write(maps[desc->ip],
230 HW_REVISION_ID, value);
237 ret = regmap_update_bits(maps[desc->ip], desc->reg,
244 ret = aspeed_sig_expr_eval(expr, enable, maps);
254 static int aspeed_sig_expr_enable(const struct aspeed_sig_expr *expr,
255 struct regmap * const *maps)
259 ret = aspeed_sig_expr_eval(expr, true, maps);
264 return aspeed_sig_expr_set(expr, true, maps);
269 static int aspeed_sig_expr_disable(const struct aspeed_sig_expr *expr,
270 struct regmap * const *maps)
274 ret = aspeed_sig_expr_eval(expr, true, maps);
279 return aspeed_sig_expr_set(expr, false, maps);
285 * Disable a signal on a pin by disabling all provided signal expressions.
287 * @exprs: The list of signal expressions (from a priority level on a pin)
288 * @maps: The list of regmap instances for pinmux register access.
290 * Return: 0 if all expressions are disabled, otherwise a negative error code
292 static int aspeed_disable_sig(const struct aspeed_sig_expr **exprs,
293 struct regmap * const *maps)
300 while (*exprs && !ret) {
301 ret = aspeed_sig_expr_disable(*exprs, maps);
309 * Search for the signal expression needed to enable the pin's signal for the
310 * requested function.
312 * @exprs: List of signal expressions (haystack)
313 * @name: The name of the requested function (needle)
315 * Return: A pointer to the signal expression whose function tag matches the
316 * provided name, otherwise NULL.
319 static const struct aspeed_sig_expr *aspeed_find_expr_by_name(
320 const struct aspeed_sig_expr **exprs, const char *name)
323 if (strcmp((*exprs)->function, name) == 0)
331 static char *get_defined_attribute(const struct aspeed_pin_desc *pdesc,
333 const struct aspeed_sig_expr *))
337 const struct aspeed_sig_expr ***prios, **funcs, *expr;
339 prios = pdesc->prios;
341 while ((funcs = *prios)) {
342 while ((expr = *funcs)) {
343 const char *str = get(expr);
344 size_t delta = strlen(str) + 2;
347 expanded = krealloc(found, len + delta + 1, GFP_KERNEL);
370 found[len - 2] = '\0';
375 static const char *aspeed_sig_expr_function(const struct aspeed_sig_expr *expr)
377 return expr->function;
380 static char *get_defined_functions(const struct aspeed_pin_desc *pdesc)
382 return get_defined_attribute(pdesc, aspeed_sig_expr_function);
385 static const char *aspeed_sig_expr_signal(const struct aspeed_sig_expr *expr)
390 static char *get_defined_signals(const struct aspeed_pin_desc *pdesc)
392 return get_defined_attribute(pdesc, aspeed_sig_expr_signal);
395 int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
400 const struct aspeed_pinctrl_data *pdata =
401 pinctrl_dev_get_drvdata(pctldev);
402 const struct aspeed_pin_group *pgroup = &pdata->groups[group];
403 const struct aspeed_pin_function *pfunc =
404 &pdata->functions[function];
406 for (i = 0; i < pgroup->npins; i++) {
407 int pin = pgroup->pins[i];
408 const struct aspeed_pin_desc *pdesc = pdata->pins[pin].drv_data;
409 const struct aspeed_sig_expr *expr = NULL;
410 const struct aspeed_sig_expr **funcs;
411 const struct aspeed_sig_expr ***prios;
413 pr_debug("Muxing pin %d for %s\n", pin, pfunc->name);
418 prios = pdesc->prios;
423 /* Disable functions at a higher priority than that requested */
424 while ((funcs = *prios)) {
425 expr = aspeed_find_expr_by_name(funcs, pfunc->name);
430 ret = aspeed_disable_sig(funcs, pdata->maps);
438 char *functions = get_defined_functions(pdesc);
439 char *signals = get_defined_signals(pdesc);
441 pr_warn("No function %s found on pin %s (%d). Found signal(s) %s for function(s) %s\n",
442 pfunc->name, pdesc->name, pin, signals,
450 ret = aspeed_sig_expr_enable(expr, pdata->maps);
458 static bool aspeed_expr_is_gpio(const struct aspeed_sig_expr *expr)
461 * The signal type is GPIO if the signal name has "GPI" as a prefix.
462 * strncmp (rather than strcmp) is used to implement the prefix
465 * expr->signal might look like "GPIOB1" in the GPIO case.
466 * expr->signal might look like "GPIT0" in the GPI case.
468 return strncmp(expr->signal, "GPI", 3) == 0;
471 static bool aspeed_gpio_in_exprs(const struct aspeed_sig_expr **exprs)
477 if (aspeed_expr_is_gpio(*exprs))
485 int aspeed_gpio_request_enable(struct pinctrl_dev *pctldev,
486 struct pinctrl_gpio_range *range,
490 const struct aspeed_pinctrl_data *pdata =
491 pinctrl_dev_get_drvdata(pctldev);
492 const struct aspeed_pin_desc *pdesc = pdata->pins[offset].drv_data;
493 const struct aspeed_sig_expr ***prios, **funcs, *expr;
498 prios = pdesc->prios;
503 /* Disable any functions of higher priority than GPIO */
504 while ((funcs = *prios)) {
505 if (aspeed_gpio_in_exprs(funcs))
508 ret = aspeed_disable_sig(funcs, pdata->maps);
516 char *signals = get_defined_signals(pdesc);
518 pr_warn("No GPIO signal type found on pin %s (%d). Found: %s\n",
519 pdesc->name, offset, signals);
528 * Disabling all higher-priority expressions is enough to enable the
529 * lowest-priority signal type. As such it has no associated
536 * If GPIO is not the lowest priority signal type, assume there is only
537 * one expression defined to enable the GPIO function
539 return aspeed_sig_expr_enable(expr, pdata->maps);
542 int aspeed_pinctrl_probe(struct platform_device *pdev,
543 struct pinctrl_desc *pdesc,
544 struct aspeed_pinctrl_data *pdata)
546 struct device *parent;
547 struct pinctrl_dev *pctl;
549 parent = pdev->dev.parent;
551 dev_err(&pdev->dev, "No parent for syscon pincontroller\n");
555 pdata->maps[ASPEED_IP_SCU] = syscon_node_to_regmap(parent->of_node);
556 if (IS_ERR(pdata->maps[ASPEED_IP_SCU])) {
557 dev_err(&pdev->dev, "No regmap for syscon pincontroller parent\n");
558 return PTR_ERR(pdata->maps[ASPEED_IP_SCU]);
561 pctl = pinctrl_register(pdesc, &pdev->dev, pdata);
564 dev_err(&pdev->dev, "Failed to register pinctrl\n");
565 return PTR_ERR(pctl);
568 platform_set_drvdata(pdev, pdata);
573 static inline bool pin_in_config_range(unsigned int offset,
574 const struct aspeed_pin_config *config)
576 return offset >= config->pins[0] && offset <= config->pins[1];
579 static inline const struct aspeed_pin_config *find_pinconf_config(
580 const struct aspeed_pinctrl_data *pdata,
582 enum pin_config_param param)
586 for (i = 0; i < pdata->nconfigs; i++) {
587 if (param == pdata->configs[i].param &&
588 pin_in_config_range(offset, &pdata->configs[i]))
589 return &pdata->configs[i];
596 * @param: pinconf configuration parameter
597 * @arg: The supported argument for @param, or -1 if any value is supported
598 * @value: The register value to write to configure @arg for @param
600 * The map is to be used in conjunction with the configuration array supplied
601 * by the driver implementation.
603 struct aspeed_pin_config_map {
604 enum pin_config_param param;
609 enum aspeed_pin_config_map_type { MAP_TYPE_ARG, MAP_TYPE_VAL };
611 /* Aspeed consistently both:
613 * 1. Defines "disable bits" for internal pull-downs
614 * 2. Uses 8mA or 16mA drive strengths
616 static const struct aspeed_pin_config_map pin_config_map[] = {
617 { PIN_CONFIG_BIAS_PULL_DOWN, 0, 1 },
618 { PIN_CONFIG_BIAS_PULL_DOWN, -1, 0 },
619 { PIN_CONFIG_BIAS_DISABLE, -1, 1 },
620 { PIN_CONFIG_DRIVE_STRENGTH, 8, 0 },
621 { PIN_CONFIG_DRIVE_STRENGTH, 16, 1 },
624 static const struct aspeed_pin_config_map *find_pinconf_map(
625 enum pin_config_param param,
626 enum aspeed_pin_config_map_type type,
631 for (i = 0; i < ARRAY_SIZE(pin_config_map); i++) {
632 const struct aspeed_pin_config_map *elem;
635 elem = &pin_config_map[i];
639 match = (elem->arg == -1 || elem->arg == value);
642 match = (elem->val == value);
646 if (param == elem->param && match)
653 int aspeed_pin_config_get(struct pinctrl_dev *pctldev, unsigned int offset,
654 unsigned long *config)
656 const enum pin_config_param param = pinconf_to_config_param(*config);
657 const struct aspeed_pin_config_map *pmap;
658 const struct aspeed_pinctrl_data *pdata;
659 const struct aspeed_pin_config *pconf;
664 pdata = pinctrl_dev_get_drvdata(pctldev);
665 pconf = find_pinconf_config(pdata, offset, param);
669 rc = regmap_read(pdata->maps[ASPEED_IP_SCU], pconf->reg, &val);
673 pmap = find_pinconf_map(param, MAP_TYPE_VAL,
674 (val & BIT(pconf->bit)) >> pconf->bit);
679 if (param == PIN_CONFIG_DRIVE_STRENGTH)
680 arg = (u32) pmap->arg;
681 else if (param == PIN_CONFIG_BIAS_PULL_DOWN)
689 *config = pinconf_to_config_packed(param, arg);
694 int aspeed_pin_config_set(struct pinctrl_dev *pctldev, unsigned int offset,
695 unsigned long *configs, unsigned int num_configs)
697 const struct aspeed_pinctrl_data *pdata;
701 pdata = pinctrl_dev_get_drvdata(pctldev);
703 for (i = 0; i < num_configs; i++) {
704 const struct aspeed_pin_config_map *pmap;
705 const struct aspeed_pin_config *pconf;
706 enum pin_config_param param;
710 param = pinconf_to_config_param(configs[i]);
711 arg = pinconf_to_config_argument(configs[i]);
713 pconf = find_pinconf_config(pdata, offset, param);
717 pmap = find_pinconf_map(param, MAP_TYPE_ARG, arg);
719 if (unlikely(WARN_ON(!pmap)))
722 val = pmap->val << pconf->bit;
724 rc = regmap_update_bits(pdata->maps[ASPEED_IP_SCU], pconf->reg,
725 BIT(pconf->bit), val);
730 pr_debug("%s: Set SCU%02X[%d]=%d for param %d(=%d) on pin %d\n",
731 __func__, pconf->reg, pconf->bit, pmap->val,
738 int aspeed_pin_config_group_get(struct pinctrl_dev *pctldev,
739 unsigned int selector,
740 unsigned long *config)
742 const unsigned int *pins;
746 rc = aspeed_pinctrl_get_group_pins(pctldev, selector, &pins, &npins);
753 rc = aspeed_pin_config_get(pctldev, pins[0], config);
758 int aspeed_pin_config_group_set(struct pinctrl_dev *pctldev,
759 unsigned int selector,
760 unsigned long *configs,
761 unsigned int num_configs)
763 const unsigned int *pins;
768 pr_debug("%s: Fetching pins for group selector %d\n",
770 rc = aspeed_pinctrl_get_group_pins(pctldev, selector, &pins, &npins);
774 for (i = 0; i < npins; i++) {
775 rc = aspeed_pin_config_set(pctldev, pins[i], configs,