platform/loongarch: laptop: Unregister generic_sub_drivers on exit

Without correct unregisteration, ACPI notify handlers and the platform
drivers installed by generic_subdriver_init() will become dangling
references after removing the loongson_laptop module, triggering various
kernel faults when a hotkey is sent or at kernel shutdown.

Cc: stable@vger.kernel.org
Fixes: 6246ed0911 ("LoongArch: Add ACPI-based generic laptop driver")
Signed-off-by: Yao Zi <ziyao@disroot.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

arch/loongarch/boot/dts/loongson-2k0500.dtsi

@@ -169,6 +169,166 @@ eiointc: interrupt-controller@1fe11600 {
 			interrupts = <3>;
 		};
 
+		pwm@1ff5c000 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c000 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <24 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c010 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c010 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <24 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c020 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c020 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <24 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c030 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c030 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <24 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c040 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c040 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <25 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c050 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c050 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <25 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c060 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c060 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <25 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c070 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c070 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <25 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c080 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c080 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <26 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c090 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c090 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <26 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c0a0 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c0a0 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <26 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c0b0 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c0b0 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <26 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c0c0 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c0c0 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <27 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c0d0 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c0d0 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <27 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c0e0 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c0e0 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <27 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1ff5c0f0 {
+			compatible = "loongson,ls2k0500-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1ff5c0f0 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <27 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
 		gmac0: ethernet@1f020000 {
 			compatible = "snps,dwmac-3.70a";
 			reg = <0x0 0x1f020000 0x0 0x10000>;

arch/loongarch/boot/dts/loongson-2k1000-ref.dts

@@ -5,6 +5,7 @@
 
 /dts-v1/;
 
+#include "dt-bindings/thermal/thermal.h"
 #include "loongson-2k1000.dtsi"
 
 / {
@@ -38,6 +39,13 @@ linux,cma {
 			linux,cma-default;
 		};
 	};
+
+	fan0: pwm-fan {
+		compatible = "pwm-fan";
+		cooling-levels = <255 153 85 25>;
+		pwms = <&pwm1 0 100000 0>;
+		#cooling-cells = <2>;
+	};
 };
 
 &gmac0 {
@@ -92,6 +100,22 @@ &spi0 {
 	#size-cells = <0>;
 };
 
+&pwm1 {
+	status = "okay";
+
+	pinctrl-0 = <&pwm1_pins_default>;
+	pinctrl-names = "default";
+};
+
+&cpu_thermal {
+	cooling-maps {
+		map0 {
+			trip = <&cpu_alert>;
+			cooling-device = <&fan0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+		};
+	};
+};
+
 &ehci0 {
 	status = "okay";
 };

arch/loongarch/boot/dts/loongson-2k1000.dtsi

@@ -68,7 +68,7 @@ i2c-gpio-1 {
 	};
 
 	thermal-zones {
-		cpu-thermal {
+		cpu_thermal: cpu-thermal {
 			polling-delay-passive = <1000>;
 			polling-delay = <5000>;
 			thermal-sensors = <&tsensor 0>;
@@ -322,6 +322,46 @@ i2c3: i2c@1fe21800 {
 			status = "disabled";
 		};
 
+		pwm@1fe22000 {
+			compatible = "loongson,ls2k1000-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1fe22000 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <24 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm1: pwm@1fe22010 {
+			compatible = "loongson,ls2k1000-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1fe22010 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <25 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1fe22020 {
+			compatible = "loongson,ls2k1000-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1fe22020 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <26 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@1fe22030 {
+			compatible = "loongson,ls2k1000-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x1fe22030 0x0 0x10>;
+			interrupt-parent = <&liointc0>;
+			interrupts = <27 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_APB_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
 		pmc: power-management@1fe27000 {
 			compatible = "loongson,ls2k1000-pmc", "loongson,ls2k0500-pmc", "syscon";
 			reg = <0x0 0x1fe27000 0x0 0x58>;

arch/loongarch/boot/dts/loongson-2k2000.dtsi

@@ -165,6 +165,66 @@ msi: msi-controller@1fe01140 {
 			interrupt-parent = <&eiointc>;
 		};
 
+		pwm@100a0000 {
+			compatible = "loongson,ls2k2000-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x100a0000 0x0 0x10>;
+			interrupt-parent = <&pic>;
+			interrupts = <24 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_MISC_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@100a0100 {
+			compatible = "loongson,ls2k2000-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x100a0100 0x0 0x10>;
+			interrupt-parent = <&pic>;
+			interrupts = <25 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_MISC_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@100a0200 {
+			compatible = "loongson,ls2k2000-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x100a0200 0x0 0x10>;
+			interrupt-parent = <&pic>;
+			interrupts = <26 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_MISC_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@100a0300 {
+			compatible = "loongson,ls2k2000-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x100a0300 0x0 0x10>;
+			interrupt-parent = <&pic>;
+			interrupts = <27 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_MISC_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@100a0400 {
+			compatible = "loongson,ls2k2000-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x100a0400 0x0 0x10>;
+			interrupt-parent = <&pic>;
+			interrupts = <38 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_MISC_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
+		pwm@100a0500 {
+			compatible = "loongson,ls2k2000-pwm", "loongson,ls7a-pwm";
+			reg = <0x0 0x100a0500 0x0 0x10>;
+			interrupt-parent = <&pic>;
+			interrupts = <39 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk LOONGSON2_MISC_CLK>;
+			#pwm-cells = <3>;
+			status = "disabled";
+		};
+
 		rtc0: rtc@100d0100 {
 			compatible = "loongson,ls2k2000-rtc", "loongson,ls7a-rtc";
 			reg = <0x0 0x100d0100 0x0 0x100>;

arch/loongarch/include/asm/vdso/getrandom.h

@@ -20,7 +20,7 @@ static __always_inline ssize_t getrandom_syscall(void *_buffer, size_t _len, uns
 
 	asm volatile(
 	"      syscall 0\n"
-	: "+r" (ret)
+	: "=r" (ret)
 	: "r" (nr), "r" (buffer), "r" (len), "r" (flags)
 	: "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7", "$t8",
 	  "memory");

arch/loongarch/include/asm/vdso/gettimeofday.h

@@ -25,7 +25,7 @@ static __always_inline long gettimeofday_fallback(
 
 	asm volatile(
 	"       syscall 0\n"
-	: "+r" (ret)
+	: "=r" (ret)
 	: "r" (nr), "r" (tv), "r" (tz)
 	: "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7",
 	  "$t8", "memory");
@@ -44,7 +44,7 @@ static __always_inline long clock_gettime_fallback(
 
 	asm volatile(
 	"       syscall 0\n"
-	: "+r" (ret)
+	: "=r" (ret)
 	: "r" (nr), "r" (clkid), "r" (ts)
 	: "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7",
 	  "$t8", "memory");
@@ -63,7 +63,7 @@ static __always_inline int clock_getres_fallback(
 
 	asm volatile(
 	"       syscall 0\n"
-	: "+r" (ret)
+	: "=r" (ret)
 	: "r" (nr), "r" (clkid), "r" (ts)
 	: "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7",
 	  "$t8", "memory");

drivers/platform/loongarch/loongson-laptop.c

@@ -56,8 +56,7 @@ static struct input_dev *generic_inputdev;
 static acpi_handle hotkey_handle;
 static struct key_entry hotkey_keycode_map[GENERIC_HOTKEY_MAP_MAX];
 
-int loongson_laptop_turn_on_backlight(void);
-int loongson_laptop_turn_off_backlight(void);
+static bool bl_powered;
 static int loongson_laptop_backlight_update(struct backlight_device *bd);
 
 /* 2. ACPI Helpers and device model */
@@ -354,16 +353,41 @@ static int ec_backlight_level(u8 level)
 	return level;
 }
 
+static int ec_backlight_set_power(bool state)
+{
+	int status;
+	union acpi_object arg0 = { ACPI_TYPE_INTEGER };
+	struct acpi_object_list args = { 1, &arg0 };
+
+	arg0.integer.value = state;
+	status = acpi_evaluate_object(NULL, "\\BLSW", &args, NULL);
+	if (ACPI_FAILURE(status)) {
+		pr_info("Loongson lvds error: 0x%x\n", status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
 static int loongson_laptop_backlight_update(struct backlight_device *bd)
 {
-	int lvl = ec_backlight_level(bd->props.brightness);
+	bool target_powered = !backlight_is_blank(bd);
+	int ret = 0, lvl = ec_backlight_level(bd->props.brightness);
 
 	if (lvl < 0)
 		return -EIO;
-	if (ec_set_brightness(lvl))
-		return -EIO;
 
-	return 0;
+	if (target_powered == bl_powered) {
+		ret = ec_set_brightness(lvl);
+	} else {
+		ret = ec_backlight_set_power(target_powered);
+		if (ret < 0)
+			return ret;
+
+		bl_powered = target_powered;
+	}
+
+	return ret;
 }
 
 static int loongson_laptop_get_brightness(struct backlight_device *bd)
@@ -384,7 +408,7 @@ static const struct backlight_ops backlight_laptop_ops = {
 
 static int laptop_backlight_register(void)
 {
-	int status = 0;
+	int status = 0, ret;
 	struct backlight_properties props;
 
 	memset(&props, 0, sizeof(props));
@@ -392,44 +416,20 @@ static int laptop_backlight_register(void)
 	if (!acpi_evalf(hotkey_handle, &status, "ECLL", "d"))
 		return -EIO;
 
-	props.brightness = 1;
+	ret = ec_backlight_set_power(true);
+	if (ret)
+		return ret;
+
+	bl_powered = true;
+
 	props.max_brightness = status;
+	props.brightness = ec_get_brightness();
+	props.power = BACKLIGHT_POWER_ON;
 	props.type = BACKLIGHT_PLATFORM;
 
 	backlight_device_register("loongson_laptop",
 				NULL, NULL, &backlight_laptop_ops, &props);
 
-	return 0;
-}
-
-int loongson_laptop_turn_on_backlight(void)
-{
-	int status;
-	union acpi_object arg0 = { ACPI_TYPE_INTEGER };
-	struct acpi_object_list args = { 1, &arg0 };
-
-	arg0.integer.value = 1;
-	status = acpi_evaluate_object(NULL, "\\BLSW", &args, NULL);
-	if (ACPI_FAILURE(status)) {
-		pr_info("Loongson lvds error: 0x%x\n", status);
-		return -ENODEV;
-	}
-
-	return 0;
-}
-
-int loongson_laptop_turn_off_backlight(void)
-{
-	int status;
-	union acpi_object arg0 = { ACPI_TYPE_INTEGER };
-	struct acpi_object_list args = { 1, &arg0 };
-
-	arg0.integer.value = 0;
-	status = acpi_evaluate_object(NULL, "\\BLSW", &args, NULL);
-	if (ACPI_FAILURE(status)) {
-		pr_info("Loongson lvds error: 0x%x\n", status);
-		return -ENODEV;
-	}
 
 	return 0;
 }
@@ -611,11 +611,17 @@ static int __init generic_acpi_laptop_init(void)
 
 static void __exit generic_acpi_laptop_exit(void)
 {
+	int i;
+
 	if (generic_inputdev) {
-		if (input_device_registered)
-			input_unregister_device(generic_inputdev);
-		else
+		if (!input_device_registered) {
 			input_free_device(generic_inputdev);
+		} else {
+			input_unregister_device(generic_inputdev);
+
+			for (i = 0; i < ARRAY_SIZE(generic_sub_drivers); i++)
+				generic_subdriver_exit(&generic_sub_drivers[i]);
+		}
 	}
 }