sh-pfc: Shrink the pinctrl GPIO range to include real GPIOs only

As a step towards GPIO function removal, shorten the GPIO range
registered with the pinctrl core. Function GPIOs are now handled in the
GPIO handlers directly instead of going through the pinctrl API.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/sh-pfc/core.c

@@ -95,7 +95,7 @@ static bool sh_pfc_gpio_is_pin(struct sh_pfc *pfc, unsigned int gpio)
 	       (pfc->info->gpios[gpio].enum_id != 0);
 }
 
-static bool sh_pfc_gpio_is_function(struct sh_pfc *pfc, unsigned int gpio)
+bool sh_pfc_gpio_is_function(struct sh_pfc *pfc, unsigned int gpio)
 {
 	return (gpio >= pfc->info->nr_pins) && (gpio < pfc->info->nr_gpios) &&
 	       (pfc->info->gpios[gpio].enum_id != 0);

drivers/pinctrl/sh-pfc/core.h

@@ -47,6 +47,7 @@ void sh_pfc_write_bit(struct pinmux_data_reg *dr, unsigned long in_pos,
 		      unsigned long value);
 int sh_pfc_get_data_reg(struct sh_pfc *pfc, unsigned gpio,
 			struct pinmux_data_reg **drp, int *bitp);
+bool sh_pfc_gpio_is_function(struct sh_pfc *pfc, unsigned int gpio);
 int sh_pfc_gpio_to_enum(struct sh_pfc *pfc, unsigned gpio, int pos,
 			pinmux_enum_t *enum_idp);
 int sh_pfc_config_gpio(struct sh_pfc *pfc, unsigned gpio, int pinmux_type,

drivers/pinctrl/sh-pfc/gpio.c

@@ -38,12 +38,51 @@ static struct sh_pfc *gpio_to_pfc(struct gpio_chip *gc)
 
 static int sh_gpio_request(struct gpio_chip *gc, unsigned offset)
 {
-	return pinctrl_request_gpio(offset);
+	struct sh_pfc *pfc = gpio_to_pfc(gc);
+	unsigned long flags;
+	int ret = -EINVAL;
+
+	if (offset < pfc->info->nr_pins)
+		return pinctrl_request_gpio(offset);
+
+	pr_notice_once("Use of GPIO API for function requests is deprecated, convert to pinctrl\n");
+
+	spin_lock_irqsave(&pfc->lock, flags);
+
+	if (!sh_pfc_gpio_is_function(pfc, offset))
+		goto done;
+
+	if (sh_pfc_config_gpio(pfc, offset, PINMUX_TYPE_FUNCTION,
+			       GPIO_CFG_DRYRUN))
+		goto done;
+
+	if (sh_pfc_config_gpio(pfc, offset, PINMUX_TYPE_FUNCTION,
+			       GPIO_CFG_REQ))
+		goto done;
+
+	ret = 0;
+
+done:
+	spin_unlock_irqrestore(&pfc->lock, flags);
+	return ret;
 }
 
 static void sh_gpio_free(struct gpio_chip *gc, unsigned offset)
 {
-	pinctrl_free_gpio(offset);
+	struct sh_pfc *pfc = gpio_to_pfc(gc);
+	unsigned long flags;
+	int pinmux_type;
+
+	if (offset < pfc->info->nr_pins)
+		return pinctrl_free_gpio(offset);
+
+	spin_lock_irqsave(&pfc->lock, flags);
+
+	pinmux_type = pfc->info->gpios[offset].flags & PINMUX_FLAG_TYPE;
+
+	sh_pfc_config_gpio(pfc, offset, pinmux_type, GPIO_CFG_FREE);
+
+	spin_unlock_irqrestore(&pfc->lock, flags);
 }
 
 static void sh_gpio_set_value(struct sh_pfc *pfc, unsigned gpio, int value)
@@ -70,12 +109,26 @@ static int sh_gpio_get_value(struct sh_pfc *pfc, unsigned gpio)
 
 static int sh_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
 {
+	struct sh_pfc *pfc = gpio_to_pfc(gc);
+
+	if (offset >= pfc->info->nr_pins) {
+		/* Function GPIOs can only be requested, never configured. */
+		return -EINVAL;
+	}
+
 	return pinctrl_gpio_direction_input(offset);
 }
 
 static int sh_gpio_direction_output(struct gpio_chip *gc, unsigned offset,
 				    int value)
 {
+	struct sh_pfc *pfc = gpio_to_pfc(gc);
+
+	if (offset >= pfc->info->nr_pins) {
+		/* Function GPIOs can only be requested, never configured. */
+		return -EINVAL;
+	}
+
 	sh_gpio_set_value(gpio_to_pfc(gc), offset, value);
 
 	return pinctrl_gpio_direction_output(offset);

drivers/pinctrl/sh-pfc/pinctrl.c

@@ -116,21 +116,6 @@ static void sh_pfc_noop_disable(struct pinctrl_dev *pctldev, unsigned func,
 {
 }
 
-static int sh_pfc_config_function(struct sh_pfc *pfc, unsigned offset)
-{
-	if (sh_pfc_config_gpio(pfc, offset,
-			       PINMUX_TYPE_FUNCTION,
-			       GPIO_CFG_DRYRUN) != 0)
-		return -EINVAL;
-
-	if (sh_pfc_config_gpio(pfc, offset,
-			       PINMUX_TYPE_FUNCTION,
-			       GPIO_CFG_REQ) != 0)
-		return -EINVAL;
-
-	return 0;
-}
-
 static int sh_pfc_reconfig_pin(struct sh_pfc *pfc, unsigned offset,
 			       int new_type)
 {
@@ -198,19 +183,11 @@ static int sh_pfc_gpio_request_enable(struct pinctrl_dev *pctldev,
 	pinmux_type = pfc->info->gpios[offset].flags & PINMUX_FLAG_TYPE;
 
 	switch (pinmux_type) {
-	case PINMUX_TYPE_FUNCTION:
-		pr_notice_once("Use of GPIO API for function requests is "
-			       "deprecated, convert to pinctrl\n");
-		/* handle for now */
-		ret = sh_pfc_config_function(pfc, offset);
-		if (unlikely(ret < 0))
-			goto err;
-
-		break;
 	case PINMUX_TYPE_GPIO:
 	case PINMUX_TYPE_INPUT:
 	case PINMUX_TYPE_OUTPUT:
 		break;
+	case PINMUX_TYPE_FUNCTION:
 	default:
 		pr_err("Unsupported mux type (%d), bailing...\n", pinmux_type);
 		ret = -ENOTSUPP;
@@ -400,7 +377,7 @@ int sh_pfc_register_pinctrl(struct sh_pfc *pfc)
 
 	pmx->range.name = DRV_NAME,
 	pmx->range.id = 0;
-	pmx->range.npins = pfc->info->nr_gpios;
+	pmx->range.npins = pfc->info->nr_pins;
 	pmx->range.base = 0;
 	pmx->range.pin_base = 0;