linux-kernel - [PATCH v1 2/2] ACPI: PMIC: Replace open coded be16_to

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Date:   Tue, 30 Aug 2022 16:55:32 +0300
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        linux-acpi@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:     "Rafael J. Wysocki" <rafael@...nel.org>,
        Len Brown <lenb@...nel.org>, Andy Shevchenko <andy@...nel.org>,
        Mika Westerberg <mika.westerberg@...ux.intel.com>
Subject: [PATCH v1 2/2] ACPI: PMIC: Replace open coded be16_to_cpu()

It's easier to understand the nature of a data type when
it's written explicitly. With that, replace open coded
endianess conversion.

As a side effect it fixes the returned value of
intel_crc_pmic_update_aux() since ACPI PMIC core code
expects negative or zero and never uses positive one.

While at it, use macros from bits.h to reduce a room for mistake.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
---
 drivers/acpi/pmic/intel_pmic_bytcrc.c   | 24 ++++++++++++++++++------
 drivers/acpi/pmic/intel_pmic_chtdc_ti.c | 13 +++++++++----
 2 files changed, 27 insertions(+), 10 deletions(-)

diff --git a/drivers/acpi/pmic/intel_pmic_bytcrc.c b/drivers/acpi/pmic/intel_pmic_bytcrc.c
index 9ea79f210965..af385cec69f1 100644
--- a/drivers/acpi/pmic/intel_pmic_bytcrc.c
+++ b/drivers/acpi/pmic/intel_pmic_bytcrc.c
@@ -6,14 +6,20 @@
  */
 
 #include <linux/acpi.h>
+#include <linux/bits.h>
 #include <linux/init.h>
 #include <linux/mfd/intel_soc_pmic.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
+
+#include <asm/byteorder.h>
+
 #include "intel_pmic.h"
 
 #define PWR_SOURCE_SELECT	BIT(1)
 
+#define PMIC_REG_MASK		GENMASK(9. 0)
+
 #define PMIC_A0LOCK_REG		0xc5
 
 static struct pmic_table power_table[] = {
@@ -219,23 +225,29 @@ static int intel_crc_pmic_update_power(struct regmap *regmap, int reg,
 
 static int intel_crc_pmic_get_raw_temp(struct regmap *regmap, int reg)
 {
-	int temp_l, temp_h;
+	__be16 buf;
 
 	/*
 	 * Raw temperature value is 10bits: 8bits in reg
 	 * and 2bits in reg-1: bit0,1
 	 */
-	if (regmap_read(regmap, reg, &temp_l) ||
-	    regmap_read(regmap, reg - 1, &temp_h))
+	if (regmap_bulk_read(regmap, reg - 1, buf, sizeof(buf)))
 		return -EIO;
 
-	return temp_l | (temp_h & 0x3) << 8;
+	return be16_to_cpu(buf) & PMIC_REG_MASK;
 }
 
 static int intel_crc_pmic_update_aux(struct regmap *regmap, int reg, int raw)
 {
-	return regmap_write(regmap, reg, raw) ||
-		regmap_update_bits(regmap, reg - 1, 0x3, raw >> 8) ? -EIO : 0;
+	u16 mask = PMIC_REG_MASK;
+	__be16 buf;
+
+	if (regmap_bulk_read(regmap, reg - 1, buf, sizeof(buf)))
+		return -EIO;
+	buf = cpu_to_be16((be16_to_cpu(buf) & ~mask) | (raw & mask));
+	if (regmap_bulk_write(regmap, reg - 1, buf, sizeof(buf)))
+		return -EIO;
+	return 0;
 }
 
 static int intel_crc_pmic_get_policy(struct regmap *regmap,
diff --git a/drivers/acpi/pmic/intel_pmic_chtdc_ti.c b/drivers/acpi/pmic/intel_pmic_chtdc_ti.c
index 6c2a6da430ed..376bc80eb50a 100644
--- a/drivers/acpi/pmic/intel_pmic_chtdc_ti.c
+++ b/drivers/acpi/pmic/intel_pmic_chtdc_ti.c
@@ -8,12 +8,18 @@
  */
 
 #include <linux/acpi.h>
+#include <linux/bits.h>
 #include <linux/init.h>
 #include <linux/mfd/intel_soc_pmic.h>
 #include <linux/platform_device.h>
+
+#include <asm/byteorder.h>
+
 #include "intel_pmic.h"
 
 /* registers stored in 16bit BE (high:low, total 10bit) */
+#define PMIC_REG_MASK		GENMASK(9. 0)
+
 #define CHTDC_TI_VBAT		0x54
 #define CHTDC_TI_DIETEMP	0x56
 #define CHTDC_TI_BPTHERM	0x58
@@ -73,7 +79,7 @@ static int chtdc_ti_pmic_get_power(struct regmap *regmap, int reg, int bit,
 	if (regmap_read(regmap, reg, &data))
 		return -EIO;
 
-	*value = data & 1;
+	*value = data & BIT(0);
 	return 0;
 }
 
@@ -85,13 +91,12 @@ static int chtdc_ti_pmic_update_power(struct regmap *regmap, int reg, int bit,
 
 static int chtdc_ti_pmic_get_raw_temp(struct regmap *regmap, int reg)
 {
-	u8 buf[2];
+	__be16 buf;
 
 	if (regmap_bulk_read(regmap, reg, buf, sizeof(buf)))
 		return -EIO;
 
-	/* stored in big-endian */
-	return ((buf[0] & 0x03) << 8) | buf[1];
+	return be16_to_cpu(buf) & PMIC_REG_MASK;
 }
 
 static const struct intel_pmic_opregion_data chtdc_ti_pmic_opregion_data = {
-- 
2.35.1