[PATCH v2 5/5] leds: leds_lenovo_se10: LED driver for Lenovo SE10 platform

[Fiona Behrens <me@kloenk.dev>]

Add driver for the Lenovo ThinkEdge SE10 LED.

This driver supports controlling the red LED located on the front panel of the
Lenovo SE10 hardware. Additionally, it supports the hardware-triggered
functionality of the LED, which by default is tied to the WWAN trigger.

The driver is written in Rust and adds basic LED support for the SE10 platform.

Signed-off-by: Fiona Behrens <me@kloenk.dev>
---
 drivers/leds/Kconfig             |  10 +++
 drivers/leds/Makefile            |   1 +
 drivers/leds/leds_lenovo_se10.rs | 132 +++++++++++++++++++++++++++++++
 3 files changed, 143 insertions(+)
 create mode 100644 drivers/leds/leds_lenovo_se10.rs

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index b784bb74a837..89d9e98189d6 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -223,6 +223,16 @@ config LEDS_TURRIS_OMNIA
 	  side of CZ.NIC's Turris Omnia router. There are 12 RGB LEDs on the
 	  front panel.
 
+config LEDS_LENOVO_SE10
+       tristate "LED support for Lenovo ThinkEdge SE10"
+       depends on RUST
+       depends on (X86 && DMI) || COMPILE_TEST
+       depends on HAS_IOPORT
+       imply LEDS_TRIGGERS
+       help
+	This option enables basic support for the LED found on the front of
+	Lenovo's SE10 ThinkEdge. There is one user controlable LED on the front panel.
+
 config LEDS_LM3530
 	tristate "LCD Backlight driver for LM3530"
 	depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 18afbb5a23ee..2cff22cbafcf 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_LEDS_IP30)			+= leds-ip30.o
 obj-$(CONFIG_LEDS_IPAQ_MICRO)		+= leds-ipaq-micro.o
 obj-$(CONFIG_LEDS_IS31FL319X)		+= leds-is31fl319x.o
 obj-$(CONFIG_LEDS_IS31FL32XX)		+= leds-is31fl32xx.o
+obj-$(CONFIG_LEDS_LENOVO_SE10)		+= leds_lenovo_se10.o
 obj-$(CONFIG_LEDS_LM3530)		+= leds-lm3530.o
 obj-$(CONFIG_LEDS_LM3532)		+= leds-lm3532.o
 obj-$(CONFIG_LEDS_LM3533)		+= leds-lm3533.o
diff --git a/drivers/leds/leds_lenovo_se10.rs b/drivers/leds/leds_lenovo_se10.rs
new file mode 100644
index 000000000000..d704125610a4
--- /dev/null
+++ b/drivers/leds/leds_lenovo_se10.rs
@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0
+//! LED driver for  Lenovo ThinkEdge SE10.
+
+use kernel::ioport::{Region, ResourceSize};
+#[cfg(CONFIG_LEDS_TRIGGERS)]
+use kernel::leds::triggers;
+use kernel::leds::{Led, LedConfig, Operations};
+use kernel::prelude::*;
+use kernel::time::Delta;
+use kernel::{c_str, dmi_device_table};
+
+module! {
+    type: SE10,
+    name: "leds_lenovo_se10",
+    author: "Fiona Behrens <me@kloenk.dev>",
+    description: "LED driver for Lenovo ThinkEdge SE10",
+    license: "GPL",
+}
+
+dmi_device_table!(5, SE10_DMI_TABLE, [
+    "LENOVO-SE10": [SysVendor: "LENOVO", ProductName: "12NH"],
+    "LENOVO-SE10": [SysVendor: "LENOVO", ProductName: "12NJ"],
+    "LENOVO-SE10": [SysVendor: "LENOVO", ProductName: "12NK"],
+    "LENOVO-SE10": [SysVendor: "LENOVO", ProductName: "12NL"],
+    "LENOVO-SE10": [SysVendor: "LENOVO", ProductName: "12NM"],
+]);
+
+struct SE10 {
+    /// Led registration
+    _led: Pin<KBox<Led<LedSE10>>>,
+}
+
+impl kernel::Module for SE10 {
+    fn init(_module: &'static ThisModule) -> Result<Self> {
+        if SE10_DMI_TABLE.check_system().is_none() {
+            return Err(ENODEV);
+        }
+
+        let led = KBox::try_pin_init(
+            Led::register(
+                None,
+                LedConfig {
+                    name: Some(c_str!("platform:red:user")),
+                    #[cfg(CONFIG_LEDS_TRIGGERS)]
+                    hardware_trigger: Some(kernel::sync::Arc::pin_init(
+                        triggers::Hardware::register(c_str!("wwan")),
+                        GFP_KERNEL,
+                    )?),
+                    ..LedConfig::new(kernel::leds::Color::Red, LedSE10)
+                },
+            ),
+            GFP_KERNEL,
+        )?;
+
+        Ok(Self { _led: led })
+    }
+}
+
+/// Valid led commands.
+#[repr(u8)]
+#[allow(missing_docs)]
+enum LedCommand {
+    #[cfg(CONFIG_LEDS_TRIGGERS)]
+    Trigger = 0xB2,
+    Off = 0xB3,
+    On = 0xB4,
+    Blink = 0xB5,
+}
+
+struct LedSE10;
+
+impl LedSE10 {
+    /// Base address of the command port.
+    const CMD_PORT: ResourceSize = 0x6C;
+    /// Length of the command port.
+    const CMD_LEN: ResourceSize = 1;
+    /// Blink duration the hardware supports.
+    const HW_DURATION: Delta = Delta::from_millis(1000);
+
+    /// Request led region.
+    fn request_cmd_region(&self) -> Result<Region<'static>> {
+        Region::request_muxed(Self::CMD_PORT, Self::CMD_LEN, c_str!("leds_lenovo_se10"))
+            .ok_or(EBUSY)
+    }
+
+    /// Send command.
+    fn send_cmd(&self, cmd: LedCommand) -> Result {
+        let region = self.request_cmd_region()?;
+        region.outb(cmd as u8, 0);
+        Ok(())
+    }
+}
+
+#[vtable]
+impl Operations for LedSE10 {
+    type This = Led<LedSE10>;
+
+    const MAX_BRIGHTNESS: u8 = 1;
+
+    fn brightness_set(this: &mut Self::This, brightness: u8) {
+        if let Err(e) = if brightness == 0 {
+            this.data.send_cmd(LedCommand::Off)
+        } else {
+            this.data.send_cmd(LedCommand::On)
+        } {
+            pr_warn!("Failed to set led: {e:?}\n)")
+        }
+    }
+
+    fn blink_set(
+        this: &mut Self::This,
+        delay_on: Delta,
+        delay_off: Delta,
+    ) -> Result<(Delta, Delta)> {
+        if !(delay_on.is_zero() && delay_off.is_zero()
+            || delay_on == Self::HW_DURATION && delay_off == Self::HW_DURATION)
+        {
+            return Err(EINVAL);
+        }
+
+        this.data.send_cmd(LedCommand::Blink)?;
+        Ok((Self::HW_DURATION, Self::HW_DURATION))
+    }
+}
+
+#[vtable]
+#[cfg(CONFIG_LEDS_TRIGGERS)]
+impl triggers::HardwareOperations for LedSE10 {
+    fn activate(this: &mut Self::This) -> Result {
+        this.data.send_cmd(LedCommand::Trigger)
+    }
+}
-- 
2.47.0