linux-kernel - [PATCH 5.18 088/102] platform/x86: panasonic-laptop: de-obfuscate button codes

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Date:   Tue,  5 Jul 2022 13:58:54 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Stefan Seyfried <seife+kernel@...systems.com>,
        Hans de Goede <hdegoede@...hat.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.18 088/102] platform/x86: panasonic-laptop: de-obfuscate button codes

From: Stefan Seyfried <seife+kernel@...systems.com>

[ Upstream commit 65a3e6c8d3f7c346813a05f3d76fc46b640d76d6 ]

In the definition of panasonic_keymap[] the key codes are given in
decimal, later checks are done with hexadecimal values, which does
not help in understanding the code.
Additionally use two helper variables to shorten the code and make
the logic more obvious.

Fixes: ed83c9171829 ("platform/x86: panasonic-laptop: Resolve hotkey double trigger bug")
Signed-off-by: Stefan Seyfried <seife+kernel@...systems.com>
Reviewed-by: Hans de Goede <hdegoede@...hat.com>
Signed-off-by: Hans de Goede <hdegoede@...hat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Link: https://lore.kernel.org/r/20220624112340.10130-3-hdegoede@redhat.com
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/platform/x86/panasonic-laptop.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/platform/x86/panasonic-laptop.c b/drivers/platform/x86/panasonic-laptop.c
index 37850d07987d..ca6137f4000f 100644
--- a/drivers/platform/x86/panasonic-laptop.c
+++ b/drivers/platform/x86/panasonic-laptop.c
@@ -762,6 +762,8 @@ static void acpi_pcc_generate_keyinput(struct pcc_acpi *pcc)
 	struct input_dev *hotk_input_dev = pcc->input_dev;
 	int rc;
 	unsigned long long result;
+	unsigned int key;
+	unsigned int updown;
 
 	rc = acpi_evaluate_integer(pcc->handle, METHOD_HKEY_QUERY,
 				   NULL, &result);
@@ -770,18 +772,22 @@ static void acpi_pcc_generate_keyinput(struct pcc_acpi *pcc)
 		return;
 	}
 
+	key = result & 0xf;
+	updown = result & 0x80; /* 0x80 == key down; 0x00 = key up */
+
 	/* hack: some firmware sends no key down for sleep / hibernate */
-	if ((result & 0xf) == 0x7 || (result & 0xf) == 0xa) {
-		if (result & 0x80)
+	if (key == 7 || key == 10) {
+		if (updown)
 			sleep_keydown_seen = 1;
 		if (!sleep_keydown_seen)
 			sparse_keymap_report_event(hotk_input_dev,
-					result & 0xf, 0x80, false);
+					key, 0x80, false);
 	}
 
-	if ((result & 0xf) == 0x7 || (result & 0xf) == 0x9 || (result & 0xf) == 0xa) {
+	/* for the magic values, see panasonic_keymap[] above */
+	if (key == 7 || key == 9 || key == 10) {
 		if (!sparse_keymap_report_event(hotk_input_dev,
-						result & 0xf, result & 0x80, false))
+						key, updown, false))
 			pr_err("Unknown hotkey event: 0x%04llx\n", result);
 	}
 }
-- 
2.35.1