pinctrl: aspeed: Split out pinmux from general pinctrl

ASPEED have completely rearranged the System Control Unit register
layout with the AST2600. The existing code took advantage of the fact
that the AST2400 and AST2500 had layouts that were similar enough to
have little impact on the pinmux infrastructure (though there is a wart
with read-modify-write vs write-1-clear semantics of the hardware
strapping registers between the two).

Given that any similarity has been thrown out with the AST2600, separate
out the function applying an expression state to be driver-specific.
With it, extract out the pinmux macro jungle to its own header and
implementation so the pieces can be composed without dependency cycles.

Cc: Johnny Huang <johnny_huang@aspeedtech.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20190628023838.15426-8-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 37 insertions, 209 deletions

diff --git a/drivers/pinctrl/aspeed/pinctrl-aspeed.c b/drivers/pinctrl/aspeed/pinctrl-aspeed.c
index 89cf61b764cb..0a162ca24b9a 100644
--- a/drivers/pinctrl/aspeed/pinctrl-aspeed.c
+++ b/drivers/pinctrl/aspeed/pinctrl-aspeed.c
@@ -14,17 +14,11 @@
 #include "../core.h"
 #include "pinctrl-aspeed.h"
 
-static const char *const aspeed_pinmux_ips[] = {
-	[ASPEED_IP_SCU] = "SCU",
-	[ASPEED_IP_GFX] = "GFX",
-	[ASPEED_IP_LPC] = "LPC",
-};
-
 int aspeed_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
 {
 	struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
 
-	return pdata->ngroups;
+	return pdata->pinmux.ngroups;
 }
 
 const char *aspeed_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
@@ -32,7 +26,7 @@ const char *aspeed_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
 {
 	struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
 
-	return pdata->groups[group].name;
+	return pdata->pinmux.groups[group].name;
 }
 
 int aspeed_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
@@ -41,8 +35,8 @@ int aspeed_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
 {
 	struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
 
-	*pins = &pdata->groups[group].pins[0];
-	*npins = pdata->groups[group].npins;
+	*pins = &pdata->pinmux.groups[group].pins[0];
+	*npins = pdata->pinmux.groups[group].npins;
 
 	return 0;
 }
@@ -57,7 +51,7 @@ int aspeed_pinmux_get_fn_count(struct pinctrl_dev *pctldev)
 {
 	struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
 
-	return pdata->nfunctions;
+	return pdata->pinmux.nfunctions;
 }
 
 const char *aspeed_pinmux_get_fn_name(struct pinctrl_dev *pctldev,
@@ -65,7 +59,7 @@ const char *aspeed_pinmux_get_fn_name(struct pinctrl_dev *pctldev,
 {
 	struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
 
-	return pdata->functions[function].name;
+	return pdata->pinmux.functions[function].name;
 }
 
 int aspeed_pinmux_get_fn_groups(struct pinctrl_dev *pctldev,
@@ -75,208 +69,38 @@ int aspeed_pinmux_get_fn_groups(struct pinctrl_dev *pctldev,
 {
 	struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
 
-	*groups = pdata->functions[function].groups;
-	*num_groups = pdata->functions[function].ngroups;
+	*groups = pdata->pinmux.functions[function].groups;
+	*num_groups = pdata->pinmux.functions[function].ngroups;
 
 	return 0;
 }
 
-static inline void aspeed_sig_desc_print_val(
-		const struct aspeed_sig_desc *desc, bool enable, u32 rv)
-{
-	pr_debug("Want %s%X[0x%08X]=0x%X, got 0x%X from 0x%08X\n",
-			aspeed_pinmux_ips[desc->ip], desc->reg,
-			desc->mask, enable ? desc->enable : desc->disable,
-			(rv & desc->mask) >> __ffs(desc->mask), rv);
-}
-
-/**
- * Query the enabled or disabled state of a signal descriptor
- *
- * @desc: The signal descriptor of interest
- * @enabled: True to query the enabled state, false to query disabled state
- * @map: The IP block's regmap instance
- *
- * Return: 1 if the descriptor's bitfield is configured to the state
- * selected by @enabled, 0 if not, and less than zero if an unrecoverable
- * failure occurred
- *
- * Evaluation of descriptor state is non-trivial in that it is not a binary
- * outcome: The bitfields can be greater than one bit in size and thus can take
- * a value that is neither the enabled nor disabled state recorded in the
- * descriptor (typically this means a different function to the one of interest
- * is enabled). Thus we must explicitly test for either condition as required.
- */
-static int aspeed_sig_desc_eval(const struct aspeed_sig_desc *desc,
-				 bool enabled, struct regmap *map)
+static int aspeed_sig_expr_enable(const struct aspeed_pinmux_data *ctx,
+				  const struct aspeed_sig_expr *expr)
 {
 	int ret;
-	unsigned int raw;
-	u32 want;
 
-	if (!map)
-		return -ENODEV;
-
-	ret = regmap_read(map, desc->reg, &raw);
-	if (ret)
-		return ret;
-
-	aspeed_sig_desc_print_val(desc, enabled, raw);
-	want = enabled ? desc->enable : desc->disable;
-
-	return ((raw & desc->mask) >> __ffs(desc->mask)) == want;
-}
-
-/**
- * Query the enabled or disabled state for a mux function's signal on a pin
- *
- * @expr: An expression controlling the signal for a mux function on a pin
- * @enabled: True to query the enabled state, false to query disabled state
- * @maps: The list of regmap instances
- *
- * Return: 1 if the expression composed by @enabled evaluates true, 0 if not,
- * and less than zero if an unrecoverable failure occurred.
- *
- * A mux function is enabled or disabled if the function's signal expression
- * for each pin in the function's pin group evaluates true for the desired
- * state. An signal expression evaluates true if all of its associated signal
- * descriptors evaluate true for the desired state.
- *
- * If an expression's state is described by more than one bit, either through
- * multi-bit bitfields in a single signal descriptor or through multiple signal
- * descriptors of a single bit then it is possible for the expression to be in
- * neither the enabled nor disabled state. Thus we must explicitly test for
- * either condition as required.
- */
-static int aspeed_sig_expr_eval(const struct aspeed_sig_expr *expr,
-				 bool enabled, struct regmap * const *maps)
-{
-	int i;
-	int ret;
-
-	for (i = 0; i < expr->ndescs; i++) {
-		const struct aspeed_sig_desc *desc = &expr->descs[i];
-
-		ret = aspeed_sig_desc_eval(desc, enabled, maps[desc->ip]);
-		if (ret <= 0)
-			return ret;
-	}
-
-	return 1;
-}
-
-/**
- * Configure a pin's signal by applying an expression's descriptor state for
- * all descriptors in the expression.
- *
- * @expr: The expression associated with the function whose signal is to be
- *        configured
- * @enable: true to enable an function's signal through a pin's signal
- *          expression, false to disable the function's signal
- * @maps: The list of regmap instances for pinmux register access.
- *
- * Return: 0 if the expression is configured as requested and a negative error
- * code otherwise
- */
-static int aspeed_sig_expr_set(const struct aspeed_sig_expr *expr,
-				bool enable, struct regmap * const *maps)
-{
-	int ret;
-	int i;
-
-	for (i = 0; i < expr->ndescs; i++) {
-		const struct aspeed_sig_desc *desc = &expr->descs[i];
-		u32 pattern = enable ? desc->enable : desc->disable;
-		u32 val = (pattern << __ffs(desc->mask));
-
-		if (!maps[desc->ip])
-			return -ENODEV;
-
-		/*
-		 * Strap registers are configured in hardware or by early-boot
-		 * firmware. Treat them as read-only despite that we can write
-		 * them. This may mean that certain functions cannot be
-		 * deconfigured and is the reason we re-evaluate after writing
-		 * all descriptor bits.
-		 *
-		 * Port D and port E GPIO loopback modes are the only exception
-		 * as those are commonly used with front-panel buttons to allow
-		 * normal operation of the host when the BMC is powered off or
-		 * fails to boot. Once the BMC has booted, the loopback mode
-		 * must be disabled for the BMC to control host power-on and
-		 * reset.
-		 */
-		if (desc->ip == ASPEED_IP_SCU && desc->reg == HW_STRAP1 &&
-		    !(desc->mask & (BIT(21) | BIT(22))))
-			continue;
-
-		if (desc->ip == ASPEED_IP_SCU && desc->reg == HW_STRAP2)
-			continue;
-
-		/* On AST2500, Set bits in SCU70 are cleared from SCU7C */
-		if (desc->ip == ASPEED_IP_SCU && desc->reg == HW_STRAP1) {
-			unsigned int rev_id;
-
-			ret = regmap_read(maps[ASPEED_IP_SCU],
-				HW_REVISION_ID, &rev_id);
-			if (ret < 0)
-				return ret;
-
-			if (0x04 == (rev_id >> 24)) {
-				u32 value = ~val & desc->mask;
-
-				if (value) {
-					ret = regmap_write(maps[desc->ip],
-						HW_REVISION_ID, value);
-					if (ret < 0)
-						return ret;
-				}
-			}
-		}
-
-		ret = regmap_update_bits(maps[desc->ip], desc->reg,
-					 desc->mask, val);
-
-		if (ret)
-			return ret;
-	}
-
-	ret = aspeed_sig_expr_eval(expr, enable, maps);
-	if (ret < 0)
-		return ret;
-
-	if (!ret)
-		return -EPERM;
-
-	return 0;
-}
-
-static int aspeed_sig_expr_enable(const struct aspeed_sig_expr *expr,
-				   struct regmap * const *maps)
-{
-	int ret;
-
-	ret = aspeed_sig_expr_eval(expr, true, maps);
+	ret = aspeed_sig_expr_eval(ctx, expr, true);
 	if (ret < 0)
 		return ret;
 
 	if (!ret)
-		return aspeed_sig_expr_set(expr, true, maps);
+		return aspeed_sig_expr_set(ctx, expr, true);
 
 	return 0;
 }
 
-static int aspeed_sig_expr_disable(const struct aspeed_sig_expr *expr,
-				    struct regmap * const *maps)
+static int aspeed_sig_expr_disable(const struct aspeed_pinmux_data *ctx,
+				   const struct aspeed_sig_expr *expr)
 {
 	int ret;
 
-	ret = aspeed_sig_expr_eval(expr, true, maps);
+	ret = aspeed_sig_expr_eval(ctx, expr, true);
 	if (ret < 0)
 		return ret;
 
 	if (ret)
-		return aspeed_sig_expr_set(expr, false, maps);
+		return aspeed_sig_expr_set(ctx, expr, false);
 
 	return 0;
 }
@@ -284,13 +108,13 @@ static int aspeed_sig_expr_disable(const struct aspeed_sig_expr *expr,
 /**
  * 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)
- * @maps: The list of regmap instances for pinmux register access.
  *
  * Return: 0 if all expressions are disabled, otherwise a negative error code
  */
-static int aspeed_disable_sig(const struct aspeed_sig_expr **exprs,
-			       struct regmap * const *maps)
+static int aspeed_disable_sig(const struct aspeed_pinmux_data *ctx,
+			      const struct aspeed_sig_expr **exprs)
 {
 	int ret = 0;
 
@@ -298,7 +122,7 @@ static int aspeed_disable_sig(const struct aspeed_sig_expr **exprs,
 		return true;
 
 	while (*exprs && !ret) {
-		ret = aspeed_sig_expr_disable(*exprs, maps);
+		ret = aspeed_sig_expr_disable(ctx, *exprs);
 		exprs++;
 	}
 
@@ -399,9 +223,9 @@ int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
 	int ret;
 	const struct aspeed_pinctrl_data *pdata =
 		pinctrl_dev_get_drvdata(pctldev);
-	const struct aspeed_pin_group *pgroup = &pdata->groups[group];
+	const struct aspeed_pin_group *pgroup = &pdata->pinmux.groups[group];
 	const struct aspeed_pin_function *pfunc =
-		&pdata->functions[function];
+		&pdata->pinmux.functions[function];
 
 	for (i = 0; i < pgroup->npins; i++) {
 		int pin = pgroup->pins[i];
@@ -427,7 +251,7 @@ int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
 			if (expr)
 				break;
 
-			ret = aspeed_disable_sig(funcs, pdata->maps);
+			ret = aspeed_disable_sig(&pdata->pinmux, funcs);
 			if (ret)
 				return ret;
 
@@ -447,7 +271,7 @@ int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
 			return -ENXIO;
 		}
 
-		ret = aspeed_sig_expr_enable(expr, pdata->maps);
+		ret = aspeed_sig_expr_enable(&pdata->pinmux, expr);
 		if (ret)
 			return ret;
 	}
@@ -504,7 +328,7 @@ int aspeed_gpio_request_enable(struct pinctrl_dev *pctldev,
 		if (aspeed_gpio_in_exprs(funcs))
 			break;
 
-		ret = aspeed_disable_sig(funcs, pdata->maps);
+		ret = aspeed_disable_sig(&pdata->pinmux, funcs);
 		if (ret)
 			return ret;
 
@@ -535,7 +359,7 @@ int aspeed_gpio_request_enable(struct pinctrl_dev *pctldev,
 	 * If GPIO is not the lowest priority signal type, assume there is only
 	 * one expression defined to enable the GPIO function
 	 */
-	return aspeed_sig_expr_enable(expr, pdata->maps);
+	return aspeed_sig_expr_enable(&pdata->pinmux, expr);
 }
 
 int aspeed_pinctrl_probe(struct platform_device *pdev,
@@ -551,12 +375,14 @@ int aspeed_pinctrl_probe(struct platform_device *pdev,
 		return -ENODEV;
 	}
 
-	pdata->maps[ASPEED_IP_SCU] = syscon_node_to_regmap(parent->of_node);
-	if (IS_ERR(pdata->maps[ASPEED_IP_SCU])) {
+	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->maps[ASPEED_IP_SCU]);
+		return PTR_ERR(pdata->scu);
 	}
 
+	pdata->pinmux.maps[ASPEED_IP_SCU] = pdata->scu;
+
 	pctl = pinctrl_register(pdesc, &pdev->dev, pdata);
 
 	if (IS_ERR(pctl)) {
@@ -591,7 +417,9 @@ static inline const struct aspeed_pin_config *find_pinconf_config(
 	return NULL;
 }
 
-/**
+/*
+ * Aspeed pin configuration description.
+ *
  * @param: pinconf configuration parameter
  * @arg: The supported argument for @param, or -1 if any value is supported
  * @val: The register value to write to configure @arg for @param
@@ -665,7 +493,7 @@ int aspeed_pin_config_get(struct pinctrl_dev *pctldev, unsigned int offset,
 	if (!pconf)
 		return -ENOTSUPP;
 
-	rc = regmap_read(pdata->maps[ASPEED_IP_SCU], pconf->reg, &val);
+	rc = regmap_read(pdata->scu, pconf->reg, &val);
 	if (rc < 0)
 		return rc;
 
@@ -720,8 +548,8 @@ int aspeed_pin_config_set(struct pinctrl_dev *pctldev, unsigned int offset,
 
 		val = pmap->val << pconf->bit;
 
-		rc = regmap_update_bits(pdata->maps[ASPEED_IP_SCU], pconf->reg,
-				BIT(pconf->bit), val);
+		rc = regmap_update_bits(pdata->scu, pconf->reg,
+					BIT(pconf->bit), val);
 
 		if (rc < 0)
 			return rc;