| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * Copyright (C) 2016 IBM Corp. |
| */ |
| |
| #include <linux/mfd/syscon.h> |
| #include <linux/platform_device.h> |
| #include <linux/slab.h> |
| #include <linux/string.h> |
| #include "../core.h" |
| #include "pinctrl-aspeed.h" |
| |
| int aspeed_pinctrl_get_groups_count(struct pinctrl_dev *pctldev) |
| { |
| struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev); |
| |
| return pdata->pinmux.ngroups; |
| } |
| |
| const char *aspeed_pinctrl_get_group_name(struct pinctrl_dev *pctldev, |
| unsigned int group) |
| { |
| struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev); |
| |
| return pdata->pinmux.groups[group].name; |
| } |
| |
| int aspeed_pinctrl_get_group_pins(struct pinctrl_dev *pctldev, |
| unsigned int group, const unsigned int **pins, |
| unsigned int *npins) |
| { |
| struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev); |
| |
| *pins = &pdata->pinmux.groups[group].pins[0]; |
| *npins = pdata->pinmux.groups[group].npins; |
| |
| return 0; |
| } |
| |
| void aspeed_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev, |
| struct seq_file *s, unsigned int offset) |
| { |
| seq_printf(s, " %s", dev_name(pctldev->dev)); |
| } |
| |
| int aspeed_pinmux_get_fn_count(struct pinctrl_dev *pctldev) |
| { |
| struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev); |
| |
| return pdata->pinmux.nfunctions; |
| } |
| |
| const char *aspeed_pinmux_get_fn_name(struct pinctrl_dev *pctldev, |
| unsigned int function) |
| { |
| struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev); |
| |
| return pdata->pinmux.functions[function].name; |
| } |
| |
| int aspeed_pinmux_get_fn_groups(struct pinctrl_dev *pctldev, |
| unsigned int function, |
| const char * const **groups, |
| unsigned int * const num_groups) |
| { |
| struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev); |
| |
| *groups = pdata->pinmux.functions[function].groups; |
| *num_groups = pdata->pinmux.functions[function].ngroups; |
| |
| return 0; |
| } |
| |
| static int aspeed_sig_expr_enable(struct aspeed_pinmux_data *ctx, |
| const struct aspeed_sig_expr *expr) |
| { |
| int ret; |
| |
| pr_debug("Enabling signal %s for %s\n", expr->signal, |
| expr->function); |
| |
| ret = aspeed_sig_expr_eval(ctx, expr, true); |
| if (ret < 0) |
| return ret; |
| |
| if (!ret) |
| return aspeed_sig_expr_set(ctx, expr, true); |
| |
| return 0; |
| } |
| |
| static int aspeed_sig_expr_disable(struct aspeed_pinmux_data *ctx, |
| const struct aspeed_sig_expr *expr) |
| { |
| int ret; |
| |
| pr_debug("Disabling signal %s for %s\n", expr->signal, |
| expr->function); |
| |
| ret = aspeed_sig_expr_eval(ctx, expr, true); |
| if (ret < 0) |
| return ret; |
| |
| if (ret) |
| return aspeed_sig_expr_set(ctx, expr, false); |
| |
| return 0; |
| } |
| |
| /** |
| * aspeed_disable_sig() - Disable a signal on a pin by disabling all provided |
| * signal expressions. |
| * |
| * @ctx: The pinmux context |
| * @exprs: The list of signal expressions (from a priority level on a pin) |
| * |
| * Return: 0 if all expressions are disabled, otherwise a negative error code |
| */ |
| static int aspeed_disable_sig(struct aspeed_pinmux_data *ctx, |
| const struct aspeed_sig_expr **exprs) |
| { |
| int ret = 0; |
| |
| if (!exprs) |
| return true; |
| |
| while (*exprs && !ret) { |
| ret = aspeed_sig_expr_disable(ctx, *exprs); |
| exprs++; |
| } |
| |
| return ret; |
| } |
| |
| /** |
| * aspeed_find_expr_by_name - Search for the signal expression needed to |
| * enable the pin's signal for the requested function. |
| * |
| * @exprs: List of signal expressions (haystack) |
| * @name: The name of the requested function (needle) |
| * |
| * Return: A pointer to the signal expression whose function tag matches the |
| * provided name, otherwise NULL. |
| * |
| */ |
| static const struct aspeed_sig_expr *aspeed_find_expr_by_name( |
| const struct aspeed_sig_expr **exprs, const char *name) |
| { |
| while (*exprs) { |
| if (strcmp((*exprs)->function, name) == 0) |
| return *exprs; |
| exprs++; |
| } |
| |
| return NULL; |
| } |
| |
| static char *get_defined_attribute(const struct aspeed_pin_desc *pdesc, |
| const char *(*get)( |
| const struct aspeed_sig_expr *)) |
| { |
| char *found = NULL; |
| size_t len = 0; |
| const struct aspeed_sig_expr ***prios, **funcs, *expr; |
| |
| prios = pdesc->prios; |
| |
| while ((funcs = *prios)) { |
| while ((expr = *funcs)) { |
| const char *str = get(expr); |
| size_t delta = strlen(str) + 2; |
| char *expanded; |
| |
| expanded = krealloc(found, len + delta + 1, GFP_KERNEL); |
| if (!expanded) { |
| kfree(found); |
| return expanded; |
| } |
| |
| found = expanded; |
| found[len] = '\0'; |
| len += delta; |
| |
| strcat(found, str); |
| strcat(found, ", "); |
| |
| funcs++; |
| } |
| prios++; |
| } |
| |
| if (len < 2) { |
| kfree(found); |
| return NULL; |
| } |
| |
| found[len - 2] = '\0'; |
| |
| return found; |
| } |
| |
| static const char *aspeed_sig_expr_function(const struct aspeed_sig_expr *expr) |
| { |
| return expr->function; |
| } |
| |
| static char *get_defined_functions(const struct aspeed_pin_desc *pdesc) |
| { |
| return get_defined_attribute(pdesc, aspeed_sig_expr_function); |
| } |
| |
| static const char *aspeed_sig_expr_signal(const struct aspeed_sig_expr *expr) |
| { |
| return expr->signal; |
| } |
| |
| static char *get_defined_signals(const struct aspeed_pin_desc *pdesc) |
| { |
| return get_defined_attribute(pdesc, aspeed_sig_expr_signal); |
| } |
| |
| int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function, |
| unsigned int group) |
| { |
| int i; |
| int ret; |
| struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev); |
| const struct aspeed_pin_group *pgroup = &pdata->pinmux.groups[group]; |
| const struct aspeed_pin_function *pfunc = |
| &pdata->pinmux.functions[function]; |
| |
| for (i = 0; i < pgroup->npins; i++) { |
| int pin = pgroup->pins[i]; |
| const struct aspeed_pin_desc *pdesc = pdata->pins[pin].drv_data; |
| const struct aspeed_sig_expr *expr = NULL; |
| const struct aspeed_sig_expr **funcs; |
| const struct aspeed_sig_expr ***prios; |
| |
| if (!pdesc) |
| return -EINVAL; |
| |
| pr_debug("Muxing pin %s for %s\n", pdesc->name, pfunc->name); |
| |
| prios = pdesc->prios; |
| |
| if (!prios) |
| continue; |
| |
| /* Disable functions at a higher priority than that requested */ |
| while ((funcs = *prios)) { |
| expr = aspeed_find_expr_by_name(funcs, pfunc->name); |
| |
| if (expr) |
| break; |
| |
| ret = aspeed_disable_sig(&pdata->pinmux, funcs); |
| if (ret) |
| return ret; |
| |
| prios++; |
| } |
| |
| if (!expr) { |
| char *functions = get_defined_functions(pdesc); |
| char *signals = get_defined_signals(pdesc); |
| |
| pr_warn("No function %s found on pin %s (%d). Found signal(s) %s for function(s) %s\n", |
| pfunc->name, pdesc->name, pin, signals, |
| functions); |
| kfree(signals); |
| kfree(functions); |
| |
| return -ENXIO; |
| } |
| |
| ret = aspeed_sig_expr_enable(&pdata->pinmux, expr); |
| if (ret) |
| return ret; |
| |
| pr_debug("Muxed pin %s as %s for %s\n", pdesc->name, expr->signal, |
| expr->function); |
| } |
| |
| return 0; |
| } |
| |
| static bool aspeed_expr_is_gpio(const struct aspeed_sig_expr *expr) |
| { |
| /* |
| * We need to differentiate between GPIO and non-GPIO signals to |
| * implement the gpio_request_enable() interface. For better or worse |
| * the ASPEED pinctrl driver uses the expression names to determine |
| * whether an expression will mux a pin for GPIO. |
| * |
| * Generally we have the following - A GPIO such as B1 has: |
| * |
| * - expr->signal set to "GPIOB1" |
| * - expr->function set to "GPIOB1" |
| * |
| * Using this fact we can determine whether the provided expression is |
| * a GPIO expression by testing the signal name for the string prefix |
| * "GPIO". |
| * |
| * However, some GPIOs are input-only, and the ASPEED datasheets name |
| * them differently. An input-only GPIO such as T0 has: |
| * |
| * - expr->signal set to "GPIT0" |
| * - expr->function set to "GPIT0" |
| * |
| * It's tempting to generalise the prefix test from "GPIO" to "GPI" to |
| * account for both GPIOs and GPIs, but in doing so we run aground on |
| * another feature: |
| * |
| * Some pins in the ASPEED BMC SoCs have a "pass-through" GPIO |
| * function where the input state of one pin is replicated as the |
| * output state of another (as if they were shorted together - a mux |
| * configuration that is typically enabled by hardware strapping). |
| * This feature allows the BMC to pass e.g. power button state through |
| * to the host while the BMC is yet to boot, but take control of the |
| * button state once the BMC has booted by muxing each pin as a |
| * separate, pin-specific GPIO. |
| * |
| * Conceptually this pass-through mode is a form of GPIO and is named |
| * as such in the datasheets, e.g. "GPID0". This naming similarity |
| * trips us up with the simple GPI-prefixed-signal-name scheme |
| * discussed above, as the pass-through configuration is not what we |
| * want when muxing a pin as GPIO for the GPIO subsystem. |
| * |
| * On e.g. the AST2400, a pass-through function "GPID0" is grouped on |
| * balls A18 and D16, where we have: |
| * |
| * For ball A18: |
| * - expr->signal set to "GPID0IN" |
| * - expr->function set to "GPID0" |
| * |
| * For ball D16: |
| * - expr->signal set to "GPID0OUT" |
| * - expr->function set to "GPID0" |
| * |
| * By contrast, the pin-specific GPIO expressions for the same pins are |
| * as follows: |
| * |
| * For ball A18: |
| * - expr->signal looks like "GPIOD0" |
| * - expr->function looks like "GPIOD0" |
| * |
| * For ball D16: |
| * - expr->signal looks like "GPIOD1" |
| * - expr->function looks like "GPIOD1" |
| * |
| * Testing both the signal _and_ function names gives us the means |
| * differentiate the pass-through GPIO pinmux configuration from the |
| * pin-specific configuration that the GPIO subsystem is after: An |
| * expression is a pin-specific (non-pass-through) GPIO configuration |
| * if the signal prefix is "GPI" and the signal name matches the |
| * function name. |
| */ |
| return !strncmp(expr->signal, "GPI", 3) && |
| !strcmp(expr->signal, expr->function); |
| } |
| |
| static bool aspeed_gpio_in_exprs(const struct aspeed_sig_expr **exprs) |
| { |
| if (!exprs) |
| return false; |
| |
| while (*exprs) { |
| if (aspeed_expr_is_gpio(*exprs)) |
| return true; |
| exprs++; |
| } |
| |
| return false; |
| } |
| |
| int aspeed_gpio_request_enable(struct pinctrl_dev *pctldev, |
| struct pinctrl_gpio_range *range, |
| unsigned int offset) |
| { |
| int ret; |
| struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev); |
| const struct aspeed_pin_desc *pdesc = pdata->pins[offset].drv_data; |
| const struct aspeed_sig_expr ***prios, **funcs, *expr; |
| |
| if (!pdesc) |
| return -EINVAL; |
| |
| prios = pdesc->prios; |
| |
| if (!prios) |
| return -ENXIO; |
| |
| pr_debug("Muxing pin %s for GPIO\n", pdesc->name); |
| |
| /* Disable any functions of higher priority than GPIO */ |
| while ((funcs = *prios)) { |
| if (aspeed_gpio_in_exprs(funcs)) |
| break; |
| |
| ret = aspeed_disable_sig(&pdata->pinmux, funcs); |
| if (ret) |
| return ret; |
| |
| prios++; |
| } |
| |
| if (!funcs) { |
| char *signals = get_defined_signals(pdesc); |
| |
| pr_warn("No GPIO signal type found on pin %s (%d). Found: %s\n", |
| pdesc->name, offset, signals); |
| kfree(signals); |
| |
| return -ENXIO; |
| } |
| |
| expr = *funcs; |
| |
| /* |
| * Disabling all higher-priority expressions is enough to enable the |
| * lowest-priority signal type. As such it has no associated |
| * expression. |
| */ |
| if (!expr) { |
| pr_debug("Muxed pin %s as GPIO\n", pdesc->name); |
| return 0; |
| } |
| |
| /* |
| * If GPIO is not the lowest priority signal type, assume there is only |
| * one expression defined to enable the GPIO function |
| */ |
| ret = aspeed_sig_expr_enable(&pdata->pinmux, expr); |
| if (ret) |
| return ret; |
| |
| pr_debug("Muxed pin %s as %s\n", pdesc->name, expr->signal); |
| |
| return 0; |
| } |
| |
| int aspeed_pinctrl_probe(struct platform_device *pdev, |
| struct pinctrl_desc *pdesc, |
| struct aspeed_pinctrl_data *pdata) |
| { |
| struct device *parent; |
| struct pinctrl_dev *pctl; |
| |
| parent = pdev->dev.parent; |
| if (!parent) { |
| dev_err(&pdev->dev, "No parent for syscon pincontroller\n"); |
| return -ENODEV; |
| } |
| |
| pdata->scu = syscon_node_to_regmap(parent->of_node); |
| if (IS_ERR(pdata->scu)) { |
| dev_err(&pdev->dev, "No regmap for syscon pincontroller parent\n"); |
| return PTR_ERR(pdata->scu); |
| } |
| |
| pdata->pinmux.maps[ASPEED_IP_SCU] = pdata->scu; |
| |
| pctl = pinctrl_register(pdesc, &pdev->dev, pdata); |
| |
| if (IS_ERR(pctl)) { |
| dev_err(&pdev->dev, "Failed to register pinctrl\n"); |
| return PTR_ERR(pctl); |
| } |
| |
| platform_set_drvdata(pdev, pdata); |
| |
| return 0; |
| } |
| |
| static inline bool pin_in_config_range(unsigned int offset, |
| const struct aspeed_pin_config *config) |
| { |
| return offset >= config->pins[0] && offset <= config->pins[1]; |
| } |
| |
| static inline const struct aspeed_pin_config *find_pinconf_config( |
| const struct aspeed_pinctrl_data *pdata, |
| unsigned int offset, |
| enum pin_config_param param) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < pdata->nconfigs; i++) { |
| if (param == pdata->configs[i].param && |
| pin_in_config_range(offset, &pdata->configs[i])) |
| return &pdata->configs[i]; |
| } |
| |
| return NULL; |
| } |
| |
| enum aspeed_pin_config_map_type { MAP_TYPE_ARG, MAP_TYPE_VAL }; |
| |
| static const struct aspeed_pin_config_map *find_pinconf_map( |
| const struct aspeed_pinctrl_data *pdata, |
| enum pin_config_param param, |
| enum aspeed_pin_config_map_type type, |
| s64 value) |
| { |
| int i; |
| |
| for (i = 0; i < pdata->nconfmaps; i++) { |
| const struct aspeed_pin_config_map *elem; |
| bool match; |
| |
| elem = &pdata->confmaps[i]; |
| |
| switch (type) { |
| case MAP_TYPE_ARG: |
| match = (elem->arg == -1 || elem->arg == value); |
| break; |
| case MAP_TYPE_VAL: |
| match = (elem->val == value); |
| break; |
| } |
| |
| if (param == elem->param && match) |
| return elem; |
| } |
| |
| return NULL; |
| } |
| |
| int aspeed_pin_config_get(struct pinctrl_dev *pctldev, unsigned int offset, |
| unsigned long *config) |
| { |
| const enum pin_config_param param = pinconf_to_config_param(*config); |
| const struct aspeed_pin_config_map *pmap; |
| const struct aspeed_pinctrl_data *pdata; |
| const struct aspeed_pin_config *pconf; |
| unsigned int val; |
| int rc = 0; |
| u32 arg; |
| |
| pdata = pinctrl_dev_get_drvdata(pctldev); |
| pconf = find_pinconf_config(pdata, offset, param); |
| if (!pconf) |
| return -ENOTSUPP; |
| |
| rc = regmap_read(pdata->scu, pconf->reg, &val); |
| if (rc < 0) |
| return rc; |
| |
| pmap = find_pinconf_map(pdata, param, MAP_TYPE_VAL, |
| (val & pconf->mask) >> __ffs(pconf->mask)); |
| |
| if (!pmap) |
| return -EINVAL; |
| |
| if (param == PIN_CONFIG_DRIVE_STRENGTH) |
| arg = (u32) pmap->arg; |
| else if (param == PIN_CONFIG_BIAS_PULL_DOWN) |
| arg = !!pmap->arg; |
| else |
| arg = 1; |
| |
| if (!arg) |
| return -EINVAL; |
| |
| *config = pinconf_to_config_packed(param, arg); |
| |
| return 0; |
| } |
| |
| int aspeed_pin_config_set(struct pinctrl_dev *pctldev, unsigned int offset, |
| unsigned long *configs, unsigned int num_configs) |
| { |
| const struct aspeed_pinctrl_data *pdata; |
| unsigned int i; |
| int rc = 0; |
| |
| pdata = pinctrl_dev_get_drvdata(pctldev); |
| |
| for (i = 0; i < num_configs; i++) { |
| const struct aspeed_pin_config_map *pmap; |
| const struct aspeed_pin_config *pconf; |
| enum pin_config_param param; |
| unsigned int val; |
| u32 arg; |
| |
| param = pinconf_to_config_param(configs[i]); |
| arg = pinconf_to_config_argument(configs[i]); |
| |
| pconf = find_pinconf_config(pdata, offset, param); |
| if (!pconf) |
| return -ENOTSUPP; |
| |
| pmap = find_pinconf_map(pdata, param, MAP_TYPE_ARG, arg); |
| |
| if (WARN_ON(!pmap)) |
| return -EINVAL; |
| |
| val = pmap->val << __ffs(pconf->mask); |
| |
| rc = regmap_update_bits(pdata->scu, pconf->reg, |
| pconf->mask, val); |
| |
| if (rc < 0) |
| return rc; |
| |
| pr_debug("%s: Set SCU%02X[0x%08X]=0x%X for param %d(=%d) on pin %d\n", |
| __func__, pconf->reg, pconf->mask, |
| val, param, arg, offset); |
| } |
| |
| return 0; |
| } |
| |
| int aspeed_pin_config_group_get(struct pinctrl_dev *pctldev, |
| unsigned int selector, |
| unsigned long *config) |
| { |
| const unsigned int *pins; |
| unsigned int npins; |
| int rc; |
| |
| rc = aspeed_pinctrl_get_group_pins(pctldev, selector, &pins, &npins); |
| if (rc < 0) |
| return rc; |
| |
| if (!npins) |
| return -ENODEV; |
| |
| rc = aspeed_pin_config_get(pctldev, pins[0], config); |
| |
| return rc; |
| } |
| |
| int aspeed_pin_config_group_set(struct pinctrl_dev *pctldev, |
| unsigned int selector, |
| unsigned long *configs, |
| unsigned int num_configs) |
| { |
| const unsigned int *pins; |
| unsigned int npins; |
| int rc; |
| int i; |
| |
| pr_debug("%s: Fetching pins for group selector %d\n", |
| __func__, selector); |
| rc = aspeed_pinctrl_get_group_pins(pctldev, selector, &pins, &npins); |
| if (rc < 0) |
| return rc; |
| |
| for (i = 0; i < npins; i++) { |
| rc = aspeed_pin_config_set(pctldev, pins[i], configs, |
| num_configs); |
| if (rc < 0) |
| return rc; |
| } |
| |
| return 0; |
| } |