linux-kernel - [PATCH] mfd: intel_soc_pmic: Use CPU-id check instead of

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Message-Id: <20211107172641.288491-1-hdegoede@redhat.com>
Date:   Sun,  7 Nov 2021 18:26:41 +0100
From:   Hans de Goede <hdegoede@...hat.com>
To:     Andy Shevchenko <andy@...nel.org>, Lee Jones <lee.jones@...aro.org>
Cc:     Hans de Goede <hdegoede@...hat.com>, linux-kernel@...r.kernel.org,
        Tsuchiya Yuto <kitakar@...il.com>
Subject: [PATCH] mfd: intel_soc_pmic: Use CPU-id check instead of _HRV check to differentiate variants

The Intel Crystal Cove PMIC has 2 different variants, one for use with
Bay Trail (BYT) SoCs and one for use with Cherry Trail (CHT) SoCs.

So far we have been using an ACPI _HRV check to differentiate between
the 2, but at least on the Microsoft Surface 3, which is a CHT device,
the wrong _HRV value is reported by ACPI.

So instead switch to a CPU-ID check which avoids us relying on the
possibly wrong ACPI _HRV value.

Reported-by: Tsuchiya Yuto <kitakar@...il.com>
Signed-off-by: Hans de Goede <hdegoede@...hat.com>
---
 drivers/mfd/intel_soc_pmic_core.c | 28 +++-------------------------
 1 file changed, 3 insertions(+), 25 deletions(-)

diff --git a/drivers/mfd/intel_soc_pmic_core.c b/drivers/mfd/intel_soc_pmic_core.c
index ddd64f9e3341..47cb7f00dfcf 100644
--- a/drivers/mfd/intel_soc_pmic_core.c
+++ b/drivers/mfd/intel_soc_pmic_core.c
@@ -14,15 +14,12 @@
 #include <linux/module.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/intel_soc_pmic.h>
+#include <linux/platform_data/x86/soc.h>
 #include <linux/pwm.h>
 #include <linux/regmap.h>
 
 #include "intel_soc_pmic_core.h"
 
-/* Crystal Cove PMIC shares same ACPI ID between different platforms */
-#define BYT_CRC_HRV		2
-#define CHT_CRC_HRV		3
-
 /* PWM consumed by the Intel GFX */
 static struct pwm_lookup crc_pwm_lookup[] = {
 	PWM_LOOKUP("crystal_cove_pwm", 0, "0000:00:02.0", "pwm_pmic_backlight", 0, PWM_POLARITY_NORMAL),
@@ -34,31 +31,12 @@ static int intel_soc_pmic_i2c_probe(struct i2c_client *i2c,
 	struct device *dev = &i2c->dev;
 	struct intel_soc_pmic_config *config;
 	struct intel_soc_pmic *pmic;
-	unsigned long long hrv;
-	acpi_status status;
 	int ret;
 
-	/*
-	 * There are 2 different Crystal Cove PMICs a Bay Trail and Cherry
-	 * Trail version, use _HRV to differentiate between the 2.
-	 */
-	status = acpi_evaluate_integer(ACPI_HANDLE(dev), "_HRV", NULL, &hrv);
-	if (ACPI_FAILURE(status)) {
-		dev_err(dev, "Failed to get PMIC hardware revision\n");
-		return -ENODEV;
-	}
-
-	switch (hrv) {
-	case BYT_CRC_HRV:
+	if (soc_intel_is_byt())
 		config = &intel_soc_pmic_config_byt_crc;
-		break;
-	case CHT_CRC_HRV:
+	else
 		config = &intel_soc_pmic_config_cht_crc;
-		break;
-	default:
-		dev_warn(dev, "Unknown hardware rev %llu, assuming BYT\n", hrv);
-		config = &intel_soc_pmic_config_byt_crc;
-	}
 
 	pmic = devm_kzalloc(dev, sizeof(*pmic), GFP_KERNEL);
 	if (!pmic)
-- 
2.31.1