linux-kernel - [PATCH v1] pinctrl: intel: refine intel_config_set

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Message-Id: <20231003081824.28810-1-raag.jadav@intel.com>
Date:   Tue,  3 Oct 2023 13:48:24 +0530
From:   Raag Jadav <raag.jadav@...el.com>
To:     linus.walleij@...aro.org, mika.westerberg@...ux.intel.com,
        andriy.shevchenko@...ux.intel.com
Cc:     linux-gpio@...r.kernel.org, linux-kernel@...r.kernel.org,
        mallikarjunappa.sangannavar@...el.com, bala.senthil@...el.com,
        Raag Jadav <raag.jadav@...el.com>
Subject: [PATCH v1] pinctrl: intel: refine intel_config_set_pull() function

Improve intel_config_set_pull() implementation in Intel pinctrl driver by:

- Reducing scope of spinlock by moving unneeded operations out of it.
- Utilizing temporary variables for common operations.
- Limiting IO operations to positive cases.

Signed-off-by: Raag Jadav <raag.jadav@...el.com>
Acked-by: Mika Westerberg <mika.westerberg@...ux.intel.com>
---
 drivers/pinctrl/intel/pinctrl-intel.c | 41 ++++++++++++++-------------
 1 file changed, 21 insertions(+), 20 deletions(-)

diff --git a/drivers/pinctrl/intel/pinctrl-intel.c b/drivers/pinctrl/intel/pinctrl-intel.c
index f49d6e136018..f9155d94a830 100644
--- a/drivers/pinctrl/intel/pinctrl-intel.c
+++ b/drivers/pinctrl/intel/pinctrl-intel.c
@@ -674,16 +674,8 @@ static int intel_config_set_pull(struct intel_pinctrl *pctrl, unsigned int pin,
 	unsigned int param = pinconf_to_config_param(config);
 	unsigned int arg = pinconf_to_config_argument(config);
 	const struct intel_community *community;
+	u32 term = 0, up = 0, value;
 	void __iomem *padcfg1;
-	u32 value;
-
-	community = intel_get_community(pctrl, pin);
-	padcfg1 = intel_get_padcfg(pctrl, pin, PADCFG1);
-
-	guard(raw_spinlock_irqsave)(&pctrl->lock);
-
-	value = readl(padcfg1);
-	value &= ~(PADCFG1_TERM_MASK | PADCFG1_TERM_UP);
 
 	/* Set default strength value in case none is given */
 	if (arg == 1)
@@ -696,47 +688,49 @@ static int intel_config_set_pull(struct intel_pinctrl *pctrl, unsigned int pin,
 	case PIN_CONFIG_BIAS_PULL_UP:
 		switch (arg) {
 		case 20000:
-			value |= PADCFG1_TERM_20K << PADCFG1_TERM_SHIFT;
+			term = PADCFG1_TERM_20K;
 			break;
 		case 5000:
-			value |= PADCFG1_TERM_5K << PADCFG1_TERM_SHIFT;
+			term = PADCFG1_TERM_5K;
 			break;
 		case 4000:
-			value |= PADCFG1_TERM_4K << PADCFG1_TERM_SHIFT;
+			term = PADCFG1_TERM_4K;
 			break;
 		case 1000:
-			value |= PADCFG1_TERM_1K << PADCFG1_TERM_SHIFT;
+			term = PADCFG1_TERM_1K;
 			break;
 		case 833:
-			value |= PADCFG1_TERM_833 << PADCFG1_TERM_SHIFT;
+			term = PADCFG1_TERM_833;
 			break;
 		default:
 			return -EINVAL;
 		}
 
-		value |= PADCFG1_TERM_UP;
+		up = PADCFG1_TERM_UP;
 		break;
 
 	case PIN_CONFIG_BIAS_PULL_DOWN:
+		community = intel_get_community(pctrl, pin);
+
 		switch (arg) {
 		case 20000:
-			value |= PADCFG1_TERM_20K << PADCFG1_TERM_SHIFT;
+			term = PADCFG1_TERM_20K;
 			break;
 		case 5000:
-			value |= PADCFG1_TERM_5K << PADCFG1_TERM_SHIFT;
+			term = PADCFG1_TERM_5K;
 			break;
 		case 4000:
-			value |= PADCFG1_TERM_4K << PADCFG1_TERM_SHIFT;
+			term = PADCFG1_TERM_4K;
 			break;
 		case 1000:
 			if (!(community->features & PINCTRL_FEATURE_1K_PD))
 				return -EINVAL;
-			value |= PADCFG1_TERM_1K << PADCFG1_TERM_SHIFT;
+			term = PADCFG1_TERM_1K;
 			break;
 		case 833:
 			if (!(community->features & PINCTRL_FEATURE_1K_PD))
 				return -EINVAL;
-			value |= PADCFG1_TERM_833 << PADCFG1_TERM_SHIFT;
+			term = PADCFG1_TERM_833;
 			break;
 		default:
 			return -EINVAL;
@@ -748,6 +742,13 @@ static int intel_config_set_pull(struct intel_pinctrl *pctrl, unsigned int pin,
 		return -EINVAL;
 	}
 
+	padcfg1 = intel_get_padcfg(pctrl, pin, PADCFG1);
+
+	guard(raw_spinlock_irqsave)(&pctrl->lock);
+
+	value = readl(padcfg1);
+	value = (value & ~PADCFG1_TERM_MASK) | (term << PADCFG1_TERM_SHIFT);
+	value = (value & ~PADCFG1_TERM_UP) | up;
 	writel(value, padcfg1);
 
 	return 0;

base-commit: cec422ab8c1ef320cba23b7dbf9ea5364b9c8207
-- 
2.17.1