[PATCH 8/9] regulator: add driver for ncv6336 regulator

[Fabien Parent <parent.f@gmail.com>]

From: Fabien Parent <fabien.parent@linaro.org>

This commit adds support for the Onsemi NCV6336 buck down converter.

Signed-off-by: Fabien Parent <fabien.parent@linaro.org>
---
 drivers/regulator/Kconfig              |   7 +
 drivers/regulator/Makefile             |   1 +
 drivers/regulator/ncv6336_regulator.rs | 241 +++++++++++++++++++++++++++++++++
 3 files changed, 249 insertions(+)

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 39297f7d8177193e51c99bc2b360c6d9936e62fe..7254a6e1d7539b147b7ba00ebcb6fd92eb6b2616 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -952,6 +952,13 @@ config REGULATOR_MTK_DVFSRC
 	  of Mediatek. It allows for voting on regulator state
 	  between multiple users.
 
+config REGULATOR_NCV6336
+	tristate "Onsemi NCV6336 regulator driver"
+	depends on RUST && OF && I2C=y
+	select REGMAP_I2C
+	help
+	  Say y here to support the Onsemi NCV6336 buck converter.
+
 config REGULATOR_PALMAS
 	tristate "TI Palmas PMIC Regulators"
 	depends on MFD_PALMAS
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 3d5a803dce8a0556ba9557fa069c6e37593b3c69..0309a78b820cc85883c0c129801ab713e08e4391 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -113,6 +113,7 @@ obj-$(CONFIG_REGULATOR_MT6370) += mt6370-regulator.o
 obj-$(CONFIG_REGULATOR_MT6380)	+= mt6380-regulator.o
 obj-$(CONFIG_REGULATOR_MT6397)	+= mt6397-regulator.o
 obj-$(CONFIG_REGULATOR_MTK_DVFSRC) += mtk-dvfsrc-regulator.o
+obj-$(CONFIG_REGULATOR_NCV6336) += ncv6336_regulator.o
 obj-$(CONFIG_REGULATOR_QCOM_LABIBB) += qcom-labibb-regulator.o
 obj-$(CONFIG_REGULATOR_QCOM_PM8008) += qcom-pm8008-regulator.o
 obj-$(CONFIG_REGULATOR_QCOM_REFGEN) += qcom-refgen-regulator.o
diff --git a/drivers/regulator/ncv6336_regulator.rs b/drivers/regulator/ncv6336_regulator.rs
new file mode 100644
index 0000000000000000000000000000000000000000..7efd7630792b68fb353ed1b1634980def9e326a1
--- /dev/null
+++ b/drivers/regulator/ncv6336_regulator.rs
@@ -0,0 +1,241 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Driver for the Onsemi Buck Converter NCV6336
+//!
+//! Datasheet: https://www.onsemi.com/pdf/datasheet/ncv6336bm-d.pdf
+
+use kernel::{
+    c_str, i2c, of,
+    prelude::*,
+    regmap::{self, BitFieldReadOps, BitFieldWriteOps, RawFieldWriteOps},
+    regulator::{
+        driver::{Config, Desc, Device, Driver, RegmapHelpers, Status, Type},
+        Mode,
+    },
+    sync::{new_mutex, Arc, Mutex},
+};
+use register::*;
+
+kernel::module_i2c_driver! {
+    type: Ncv6336,
+    name: "ncv6336",
+    author: "Fabien Parent <fabien.parent@linaro.org>",
+    license: "GPL",
+}
+
+kernel::i2c_device_table!(
+    I2C_ID_TABLE,
+    MODULE_I2C_ID_TABLE,
+    <Ncv6336 as i2c::Driver>::IdInfo,
+    [(i2c::DeviceId::new(c_str!("ncv6336")), ()),]
+);
+
+kernel::of_device_table!(
+    OF_ID_TABLE,
+    MODULE_OF_ID_TABLE,
+    <Ncv6336 as i2c::Driver>::IdInfo,
+    [(of::DeviceId::new(c_str!("onnn,ncv6336")), ()),]
+);
+
+regmap::define_regmap_field_descs!(FIELD_DESCS, {
+    (pid, 0x3, READ, { value => raw([7:0], ro) }),
+    (rid, 0x4, READ, { value => raw([7:0], ro) }),
+    (fid, 0x5, READ, { value => raw([7:0], ro) }),
+    (progvsel1, 0x10, RW, {
+        voutvsel1 => raw([6:0], rw),
+        envsel1   => bit(7, rw),
+    }),
+    (progvsel0, 0x11, RW, {
+        voutvsel0 => raw([6:0], rw),
+        envsel0   => bit(7, rw),
+    }),
+    (pgood, 0x12, RW, { dischg => bit(4, rw) }),
+    (command, 0x14, RW, {
+        vselgt   => bit(0, rw),
+        pwmvsel1 => bit(6, rw),
+        pwmvsel0 => bit(7, rw),
+    }),
+    (limconf, 0x16, RW, {
+        rearm     => bit(0, rw),
+        rststatus => bit(1, rw),
+        tpwth     => enum([5:4], rw, {
+            Temp83C  = 0x0,
+            Temp94C  = 0x1,
+            Temp105C = 0x2,
+            Temp116C = 0x3,
+        }),
+        ipeak     => enum([7:6], rw, {
+            Peak3p5A = 0x0,
+            Peak4p0A = 0x1,
+            Peak4p5A = 0x2,
+            Peak5p0A = 0x3,
+        }),
+    })
+});
+
+static NCV6336_DESC: Desc = Desc::new::<Ncv6336>(c_str!("ncv6336"), Type::Voltage)
+    .with_owner(&THIS_MODULE)
+    .with_of_match(c_str!("buck"))
+    .with_active_discharge(
+        pgood::addr(),
+        pgood::dischg::mask(),
+        pgood::dischg::mask(),
+        0,
+    )
+    .with_csel(
+        limconf::addr(),
+        limconf::ipeak::mask(),
+        &[3_500_000, 4_000_000, 4_500_000, 5_000_000],
+    )
+    .with_enable(
+        progvsel0::addr(),
+        progvsel0::envsel0::mask(),
+        progvsel0::envsel0::mask(),
+        0,
+    )
+    .with_linear_mapping(
+        progvsel0::addr(),
+        progvsel0::voutvsel0::mask(),
+        600_000,
+        6250,
+        128,
+        0,
+    );
+
+struct Ncv6336RegulatorData {
+    fields: regmap::Fields<{ FIELD_DESCS.len() }>,
+}
+
+struct Ncv6336(#[expect(dead_code)] Device<<Self as Driver>::Data>);
+
+impl i2c::Driver for Ncv6336 {
+    type IdInfo = ();
+
+    const I2C_ID_TABLE: Option<i2c::IdTable<Self::IdInfo>> = Some(&I2C_ID_TABLE);
+    const OF_ID_TABLE: Option<of::IdTable<Self::IdInfo>> = Some(&OF_ID_TABLE);
+
+    fn probe(client: &mut i2c::Client, _id_info: Option<&Self::IdInfo>) -> Result<Pin<KBox<Self>>> {
+        let config = regmap::Config::<AccessOps>::new(8, 8)
+            .with_max_register(0x16)
+            .with_cache_type(regmap::CacheType::RbTree);
+        let regmap = Arc::new(regmap::Regmap::init_i2c(client, &config)?, GFP_KERNEL)?;
+        let fields = regmap::Fields::new(&regmap, &FIELD_DESCS)?;
+
+        let data = Arc::pin_init(new_mutex!(Ncv6336RegulatorData { fields }), GFP_KERNEL)?;
+        let config = Config::new(client.as_ref(), data.clone()).with_regmap(regmap.clone());
+        let regulator = Device::register(client.as_ref(), &NCV6336_DESC, config)?;
+
+        let drvdata = KBox::new(Self(regulator), GFP_KERNEL)?;
+
+        Ok(drvdata.into())
+    }
+}
+
+#[vtable]
+impl Driver for Ncv6336 {
+    type Data = Arc<Mutex<Ncv6336RegulatorData>>;
+
+    fn list_voltage(reg: &mut Device<Self::Data>, selector: u32) -> Result<i32> {
+        reg.list_voltage_linear(selector)
+    }
+
+    fn enable(reg: &mut Device<Self::Data>) -> Result {
+        reg.enable_regmap()
+    }
+
+    fn disable(reg: &mut Device<Self::Data>) -> Result {
+        reg.disable_regmap()
+    }
+
+    fn is_enabled(reg: &mut Device<Self::Data>) -> Result<bool> {
+        reg.is_enabled_regmap()
+    }
+
+    fn set_active_discharge(reg: &mut Device<Self::Data>, enable: bool) -> Result {
+        reg.set_active_discharge_regmap(enable)
+    }
+
+    fn set_current_limit(reg: &mut Device<Self::Data>, min_ua: i32, max_ua: i32) -> Result {
+        reg.set_current_limit_regmap(min_ua, max_ua)
+    }
+
+    fn get_current_limit(reg: &mut Device<Self::Data>) -> Result<i32> {
+        reg.get_current_limit_regmap()
+    }
+
+    fn set_voltage_sel(reg: &mut Device<Self::Data>, selector: u32) -> Result {
+        reg.set_voltage_sel_regmap(selector)
+    }
+
+    fn get_voltage_sel(reg: &mut Device<Self::Data>) -> Result<i32> {
+        reg.get_voltage_sel_regmap()
+    }
+
+    fn set_mode(reg: &mut Device<Self::Data>, mode: Mode) -> Result {
+        let data = reg.data();
+        let fields = &mut data.lock().fields;
+
+        match mode {
+            Mode::Normal => command::pwmvsel0::clear(fields),
+            Mode::Fast => command::pwmvsel0::set(fields),
+            _ => Err(ENOTSUPP),
+        }
+    }
+
+    fn get_mode(reg: &mut Device<Self::Data>) -> Mode {
+        let data = reg.data();
+        let fields = &mut data.lock().fields;
+
+        match command::pwmvsel0::is_set(fields) {
+            Ok(true) => Mode::Fast,
+            Ok(false) => Mode::Normal,
+            Err(_) => Mode::Invalid,
+        }
+    }
+
+    fn get_status(reg: &mut Device<Self::Data>) -> Result<Status> {
+        if !Self::is_enabled(reg)? {
+            return Ok(Status::Off);
+        }
+
+        Ok(Self::get_mode(reg).into())
+    }
+
+    fn set_suspend_voltage(reg: &mut Device<Self::Data>, uv: i32) -> Result {
+        let data = reg.data();
+        let fields = &mut data.lock().fields;
+
+        let quot = (uv - 600000) / 6250;
+        let rem = (uv - 600000) % 6250;
+        let selector = if rem > 0 { quot + 1 } else { quot };
+
+        progvsel1::voutvsel1::write(fields, selector as _)
+    }
+
+    fn set_suspend_enable(reg: &mut Device<Self::Data>) -> Result {
+        let data = reg.data();
+        let fields = &mut data.lock().fields;
+
+        progvsel1::envsel1::set(fields)?;
+        command::vselgt::clear(fields)
+    }
+
+    fn set_suspend_disable(reg: &mut Device<Self::Data>) -> Result {
+        let data = reg.data();
+        let fields = &mut data.lock().fields;
+
+        progvsel1::envsel1::clear(fields)?;
+        command::vselgt::set(fields)
+    }
+
+    fn set_suspend_mode(reg: &mut Device<Self::Data>, mode: Mode) -> Result {
+        let data = reg.data();
+        let fields = &mut data.lock().fields;
+
+        match mode {
+            Mode::Normal => command::pwmvsel1::clear(fields),
+            Mode::Fast => command::pwmvsel1::set(fields),
+            _ => Err(ENOTSUPP),
+        }
+    }
+}

-- 
2.45.2