linux-kernel - [PATCH] pinctrl: renesas: rzg2l: Refactor OEN register PWPR handling

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Message-ID: <20251106080758.36645-1-john.madieu.xa@bp.renesas.com>
Date: Thu,  6 Nov 2025 09:07:58 +0100
From: John Madieu <john.madieu.xa@...renesas.com>
To: geert+renesas@...der.be,
	linus.walleij@...aro.org,
	prabhakar.mahadev-lad.rj@...renesas.com
Cc: biju.das.jz@...renesas.com,
	linux-renesas-soc@...r.kernel.org,
	linux-gpio@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	John Madieu <john.madieu.xa@...renesas.com>,
	Pavel Machek <pavel@...x.de>
Subject: [PATCH] pinctrl: renesas: rzg2l: Refactor OEN register PWPR handling

Extract the OEN register write with PWPR protection logic into a helper
function to eliminate code duplication between rzg2l_write_oen() and
rzg2l_pinctrl_resume_noirq().

Introduce rzg2l_oen_write_with_pwpr() helper that encapsulates the
PWPR unlock, OEN register write, and PWPR lock sequence. This helper
must be called with pctrl->lock already held by the caller.

Reported-by: Pavel Machek <pavel@...x.de>
Closes: https://lore.kernel.org/cip-dev/OS9PR01MB16368C765305362F5F4132759FFC4A@OS9PR01MB16368.jpnprd01.prod.outlook.com/T/#u
Signed-off-by: John Madieu <john.madieu.xa@...renesas.com>
---
 drivers/pinctrl/renesas/pinctrl-rzg2l.c | 53 +++++++++++++++----------
 1 file changed, 33 insertions(+), 20 deletions(-)

diff --git a/drivers/pinctrl/renesas/pinctrl-rzg2l.c b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
index f25ecada5c692..863e779dda028 100644
--- a/drivers/pinctrl/renesas/pinctrl-rzg2l.c
+++ b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
@@ -1112,13 +1112,37 @@ static int rzg2l_read_oen(struct rzg2l_pinctrl *pctrl, unsigned int _pin)
 	return !(readb(pctrl->base + pctrl->data->hwcfg->regs.oen) & BIT(bit));
 }
 
-static int rzg2l_write_oen(struct rzg2l_pinctrl *pctrl, unsigned int _pin, u8 oen)
+/**
+ * rzg2l_oen_write_with_pwpr - Write to OEN register with PWPR protection
+ * @pctrl: pinctrl driver data
+ * @val: value to write to OEN register
+ *
+ * Writes to the OEN register, handling PWPR write protection if required
+ * by the hardware configuration. Must be called with pctrl->lock held.
+ */
+static void rzg2l_oen_write_with_pwpr(struct rzg2l_pinctrl *pctrl, u8 val)
 {
 	const struct rzg2l_register_offsets *regs = &pctrl->data->hwcfg->regs;
+	u16 oen_offset = pctrl->data->hwcfg->regs.oen;
+	u8 pwpr;
+
+	if (pctrl->data->hwcfg->oen_pwpr_lock) {
+		pwpr = readb(pctrl->base + regs->pwpr);
+		writeb(pwpr | PWPR_REGWE_B, pctrl->base + regs->pwpr);
+	}
+
+	writeb(val, pctrl->base + oen_offset);
+
+	if (pctrl->data->hwcfg->oen_pwpr_lock)
+		writeb(pwpr & ~PWPR_REGWE_B, pctrl->base + regs->pwpr);
+}
+
+static int rzg2l_write_oen(struct rzg2l_pinctrl *pctrl, unsigned int _pin, u8 oen)
+{
 	u16 oen_offset = pctrl->data->hwcfg->regs.oen;
 	unsigned long flags;
-	u8 val, pwpr;
 	int bit;
+	u8 val;
 
 	if (!pctrl->data->pin_to_oen_bit)
 		return -EOPNOTSUPP;
@@ -1133,13 +1157,8 @@ static int rzg2l_write_oen(struct rzg2l_pinctrl *pctrl, unsigned int _pin, u8 oe
 		val &= ~BIT(bit);
 	else
 		val |= BIT(bit);
-	if (pctrl->data->hwcfg->oen_pwpr_lock) {
-		pwpr = readb(pctrl->base + regs->pwpr);
-		writeb(pwpr | PWPR_REGWE_B, pctrl->base + regs->pwpr);
-	}
-	writeb(val, pctrl->base + oen_offset);
-	if (pctrl->data->hwcfg->oen_pwpr_lock)
-		writeb(pwpr & ~PWPR_REGWE_B, pctrl->base + regs->pwpr);
+
+	rzg2l_oen_write_with_pwpr(pctrl, val);
 	raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 
 	return 0;
@@ -3200,7 +3219,6 @@ static int rzg2l_pinctrl_resume_noirq(struct device *dev)
 	const struct rzg2l_register_offsets *regs = &hwcfg->regs;
 	struct rzg2l_pinctrl_reg_cache *cache = pctrl->cache;
 	unsigned long flags;
-	u8 pwpr;
 	int ret;
 
 	if (!atomic_read(&pctrl->wakeup_path)) {
@@ -3210,16 +3228,11 @@ static int rzg2l_pinctrl_resume_noirq(struct device *dev)
 	}
 
 	writeb(cache->qspi, pctrl->base + QSPI);
-	if (pctrl->data->hwcfg->oen_pwpr_lock) {
-		raw_spin_lock_irqsave(&pctrl->lock, flags);
-		pwpr = readb(pctrl->base + regs->pwpr);
-		writeb(pwpr | PWPR_REGWE_B, pctrl->base + regs->pwpr);
-	}
-	writeb(cache->oen, pctrl->base + pctrl->data->hwcfg->regs.oen);
-	if (pctrl->data->hwcfg->oen_pwpr_lock) {
-		writeb(pwpr & ~PWPR_REGWE_B, pctrl->base + regs->pwpr);
-		raw_spin_unlock_irqrestore(&pctrl->lock, flags);
-	}
+
+	raw_spin_lock_irqsave(&pctrl->lock, flags);
+	rzg2l_oen_write_with_pwpr(pctrl, cache->oen);
+	raw_spin_unlock_irqrestore(&pctrl->lock, flags);
+
 	for (u8 i = 0; i < 2; i++) {
 		if (regs->sd_ch)
 			writeb(cache->sd_ch[i], pctrl->base + SD_CH(regs->sd_ch, i));
-- 
2.25.1