linux-kernel - [PATCH] Revert "mfd: syscon: Remove repetition of the regmap_get_val

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Message-Id: <20221008154700.404837-1-Jason@zx2c4.com>
Date:   Sat,  8 Oct 2022 09:47:00 -0600
From:   "Jason A. Donenfeld" <Jason@...c4.com>
To:     arnd@...db.de, lee@...nel.org, linux-kernel@...r.kernel.org,
        andriy.shevchenko@...ux.intel.com, torvalds@...ux-foundation.org
Cc:     "Jason A. Donenfeld" <Jason@...c4.com>
Subject: [PATCH] Revert "mfd: syscon: Remove repetition of the regmap_get_val_endian()"

This reverts commit 72a95859728a7866522e6633818bebc1c2519b17. It broke
reboots on big-endian MIPS and MIPS64 malta QEMU instances, which use
the syscon driver. Little-endian is not effected, which means likely
it's important to handle regmap_get_val_endian() in this function after
all.

Cc: Lee Jones <lee@...nel.org>
Cc: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Fixes: 72a95859728a ("mfd: syscon: Remove repetition of the regmap_get_val_endian()")
Signed-off-by: Jason A. Donenfeld <Jason@...c4.com>
---
 drivers/mfd/syscon.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index 9489e80e905a..bdb2ce7ff03b 100644
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -66,6 +66,14 @@ static struct syscon *of_syscon_register(struct device_node *np, bool check_clk)
 		goto err_map;
 	}
 
+	/* Parse the device's DT node for an endianness specification */
+	if (of_property_read_bool(np, "big-endian"))
+		syscon_config.val_format_endian = REGMAP_ENDIAN_BIG;
+	else if (of_property_read_bool(np, "little-endian"))
+		syscon_config.val_format_endian = REGMAP_ENDIAN_LITTLE;
+	else if (of_property_read_bool(np, "native-endian"))
+		syscon_config.val_format_endian = REGMAP_ENDIAN_NATIVE;
+
 	/*
 	 * search for reg-io-width property in DT. If it is not provided,
 	 * default to 4 bytes. regmap_init_mmio will return an error if values
-- 
2.37.3