[PATCH 1/2] pinctrl: cy8c95x0: Use cleanup.h

[PATCH 1/2] pinctrl: cy8c95x0: Use cleanup.h

[Patrick Rudolph]

Use the guard mutex from cleanup.h to make the code more readable.

Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
---
 drivers/pinctrl/pinctrl-cy8c95x0.c | 13 ++++---------
 1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-cy8c95x0.c b/drivers/pinctrl/pinctrl-cy8c95x0.c
index 4efb8b5cc2d3..781949e0e09e 100644
--- a/drivers/pinctrl/pinctrl-cy8c95x0.c
+++ b/drivers/pinctrl/pinctrl-cy8c95x0.c
@@ -9,6 +9,7 @@
 
 #include <linux/acpi.h>
 #include <linux/bitmap.h>
+#include <linux/cleanup.h>
 #include <linux/dmi.h>
 #include <linux/gpio/driver.h>
 #include <linux/gpio/consumer.h>
@@ -480,8 +481,6 @@ static inline int cy8c95x0_regmap_update_bits_base(struct cy8c95x0_pinctrl *chip
 	if (reg == CY8C95X0_PORTSEL)
 		return -EINVAL;
 
-	mutex_lock(&chip->i2c_lock);
-
 	/* Registers behind the PORTSEL mux have their own range in regmap */
 	if (cy8c95x0_muxed_register(reg)) {
 		off = CY8C95X0_MUX_REGMAP_TO_OFFSET(reg, port);
@@ -492,10 +491,11 @@ static inline int cy8c95x0_regmap_update_bits_base(struct cy8c95x0_pinctrl *chip
 		else
 			off = reg;
 	}
+	guard(mutex)(&chip->i2c_lock);
 
 	ret = regmap_update_bits_base(chip->regmap, off, mask, val, change, async, force);
 	if (ret < 0)
-		goto out;
+		return ret;
 
 	/* Update the cache when a WC bit is written */
 	if (cy8c95x0_wc_register(reg) && (mask & val)) {
@@ -516,8 +516,6 @@ static inline int cy8c95x0_regmap_update_bits_base(struct cy8c95x0_pinctrl *chip
 			regcache_cache_only(chip->regmap, false);
 		}
 	}
-out:
-	mutex_unlock(&chip->i2c_lock);
 
 	return ret;
 }
@@ -591,8 +589,6 @@ static int cy8c95x0_regmap_read(struct cy8c95x0_pinctrl *chip, unsigned int reg,
 {
 	int off, ret;
 
-	mutex_lock(&chip->i2c_lock);
-
 	/* Registers behind the PORTSEL mux have their own range in regmap */
 	if (cy8c95x0_muxed_register(reg)) {
 		off = CY8C95X0_MUX_REGMAP_TO_OFFSET(reg, port);
@@ -603,11 +599,10 @@ static int cy8c95x0_regmap_read(struct cy8c95x0_pinctrl *chip, unsigned int reg,
 		else
 			off = reg;
 	}
+	guard(mutex)(&chip->i2c_lock);
 
 	ret = regmap_read(chip->regmap, off, read_val);
 
-	mutex_unlock(&chip->i2c_lock);
-
 	return ret;
 }
 
-- 
2.44.0

[PATCH 2/2] pinctrl: cy8c95x0: Update cache modification

[Patrick Rudolph]

In the previous review cycle the regmap cache update code was
questioned since it seems and odd way of using regmap_update_bits().
Thus update the regmap cache modification code to better explain
what it does and why it's done. This is no functional change, but
it's improving code maintainability.

Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
---
 drivers/pinctrl/pinctrl-cy8c95x0.c | 22 +++++++++-------------
 1 file changed, 9 insertions(+), 13 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-cy8c95x0.c b/drivers/pinctrl/pinctrl-cy8c95x0.c
index 781949e0e09e..9a92707d2525 100644
--- a/drivers/pinctrl/pinctrl-cy8c95x0.c
+++ b/drivers/pinctrl/pinctrl-cy8c95x0.c
@@ -475,7 +475,7 @@ static inline int cy8c95x0_regmap_update_bits_base(struct cy8c95x0_pinctrl *chip
 						   bool *change, bool async,
 						   bool force)
 {
-	int ret, off, i, read_val;
+	int ret, off, i;
 
 	/* Caller should never modify PORTSEL directly */
 	if (reg == CY8C95X0_PORTSEL)
@@ -497,24 +497,20 @@ static inline int cy8c95x0_regmap_update_bits_base(struct cy8c95x0_pinctrl *chip
 	if (ret < 0)
 		return ret;
 
-	/* Update the cache when a WC bit is written */
+	/* Mimic what hardware does and update the cache when a WC bit is written.
+	 * Allows to mark the registers as non-volatile and reduces I/O cycles.
+	 */
 	if (cy8c95x0_wc_register(reg) && (mask & val)) {
+		/* Writing a 1 clears set bits in the other drive mode registers */
+		regcache_cache_only(chip->regmap, true);
 		for (i = CY8C95X0_DRV_PU; i <= CY8C95X0_DRV_HIZ; i++) {
 			if (i == reg)
 				continue;
-			off = CY8C95X0_MUX_REGMAP_TO_OFFSET(i, port);
-
-			ret = regmap_read(chip->regmap, off, &read_val);
-			if (ret < 0)
-				continue;
 
-			if (!(read_val & mask & val))
-				continue;
-
-			regcache_cache_only(chip->regmap, true);
-			regmap_update_bits(chip->regmap, off, mask & val, 0);
-			regcache_cache_only(chip->regmap, false);
+			off = CY8C95X0_MUX_REGMAP_TO_OFFSET(i, port);
+			regmap_clear_bits(chip->regmap, off, mask & val);
 		}
+		regcache_cache_only(chip->regmap, false);
 	}
 
 	return ret;
-- 
2.44.0

Re: [PATCH 2/2] pinctrl: cy8c95x0: Update cache modification

[Linus Walleij]

On Wed, Jun 26, 2024 at 10:45 AM Patrick Rudolph
<patrick.rudolph@9elements.com> wrote:

> In the previous review cycle the regmap cache update code was
> questioned since it seems and odd way of using regmap_update_bits().
> Thus update the regmap cache modification code to better explain
> what it does and why it's done. This is no functional change, but
> it's improving code maintainability.
>
> Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>

Patch applied.

Yours,
Linus Walleij

Re: [PATCH 1/2] pinctrl: cy8c95x0: Use cleanup.h

[Linus Walleij]

On Wed, Jun 26, 2024 at 10:45 AM Patrick Rudolph
<patrick.rudolph@9elements.com> wrote:

> Use the guard mutex from cleanup.h to make the code more readable.
>
> Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>

Patch applied.

Yours,
Linus Walleij