Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 658 insertions, 0 deletions

diff --git a/drivers/pinctrl/aspeed/pinctrl-aspeed.c b/drivers/pinctrl/aspeed/pinctrl-aspeed.c
new file mode 100644
index 000000000..5a12fc7cf
--- /dev/null
+++ b/drivers/pinctrl/aspeed/pinctrl-aspeed.c
@@ -0,0 +1,658 @@
+// 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 -EINVAL;
+
+	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;
+}