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| 1 | +// SPDX-License-Identifier: GPL-2.0-only OR MIT |
| 2 | + |
| 3 | +//! Apple AOP ambient light sensor driver |
| 4 | +//! |
| 5 | +//! Copyright (C) The Asahi Linux Contributors |
| 6 | +
|
| 7 | +use kernel::{ |
| 8 | + bindings, c_str, device, |
| 9 | + iio::common::aop_sensors::{AopSensorData, IIORegistration, MessageProcessor}, |
| 10 | + module_platform_driver, |
| 11 | + of::{self, Node}, |
| 12 | + platform, |
| 13 | + prelude::*, |
| 14 | + soc::apple::aop::{EPICService, AOP}, |
| 15 | + sync::Arc, |
| 16 | + types::{ARef, ForeignOwnable}, |
| 17 | +}; |
| 18 | + |
| 19 | +const EPIC_SUBTYPE_SET_ALS_PROPERTY: u16 = 0x4; |
| 20 | + |
| 21 | +fn enable_als( |
| 22 | + aop: &dyn AOP, |
| 23 | + dev: &ARef<device::Device>, |
| 24 | + of: &Node, |
| 25 | + svc: &EPICService, |
| 26 | +) -> Result<()> { |
| 27 | + if let Some(prop) = of.find_property(c_str!("apple,als-calibration")) { |
| 28 | + set_als_property(aop, svc, 0xb, prop.value())?; |
| 29 | + set_als_property(aop, svc, 0, &200000u32.to_le_bytes())?; |
| 30 | + } else { |
| 31 | + dev_warn!(dev, "ALS Calibration not found, will not enable it"); |
| 32 | + } |
| 33 | + Ok(()) |
| 34 | +} |
| 35 | +fn set_als_property(aop: &dyn AOP, svc: &EPICService, tag: u32, data: &[u8]) -> Result<u32> { |
| 36 | + let mut buf = KVec::new(); |
| 37 | + buf.resize(data.len() + 8, 0, GFP_KERNEL)?; |
| 38 | + buf[8..].copy_from_slice(data); |
| 39 | + buf[4..8].copy_from_slice(&tag.to_le_bytes()); |
| 40 | + aop.epic_call(svc, EPIC_SUBTYPE_SET_ALS_PROPERTY, &buf) |
| 41 | +} |
| 42 | + |
| 43 | +fn f32_to_u32(f: u32) -> u32 { |
| 44 | + if f & 0x80000000 != 0 { |
| 45 | + return 0; |
| 46 | + } |
| 47 | + let exp = ((f & 0x7f800000) >> 23) as i32 - 127; |
| 48 | + if exp < 0 { |
| 49 | + return 0; |
| 50 | + } |
| 51 | + if exp == 128 && f & 0x7fffff != 0 { |
| 52 | + return 0; |
| 53 | + } |
| 54 | + let mant = f & 0x7fffff | 0x800000; |
| 55 | + if exp <= 23 { |
| 56 | + return mant >> (23 - exp); |
| 57 | + } |
| 58 | + if exp >= 32 { |
| 59 | + return u32::MAX; |
| 60 | + } |
| 61 | + mant << (exp - 23) |
| 62 | +} |
| 63 | + |
| 64 | +struct MsgProc(usize); |
| 65 | + |
| 66 | +impl MessageProcessor for MsgProc { |
| 67 | + fn process(&self, message: &[u8]) -> u32 { |
| 68 | + let offset = self.0; |
| 69 | + let raw = u32::from_le_bytes(message[offset..offset + 4].try_into().unwrap()); |
| 70 | + f32_to_u32(raw) |
| 71 | + } |
| 72 | +} |
| 73 | + |
| 74 | +#[repr(transparent)] |
| 75 | +struct IIOAopAlsDriver(IIORegistration<MsgProc>); |
| 76 | + |
| 77 | +kernel::of_device_table!(OF_TABLE, MODULE_OF_TABLE, (), [] as [(of::DeviceId, ()); 0]); |
| 78 | + |
| 79 | +impl platform::Driver for IIOAopAlsDriver { |
| 80 | + type IdInfo = (); |
| 81 | + |
| 82 | + const ID_TABLE: platform::IdTable<()> = &OF_TABLE; |
| 83 | + |
| 84 | + fn probe( |
| 85 | + pdev: &mut platform::Device, |
| 86 | + _info: Option<&()>, |
| 87 | + ) -> Result<Pin<KBox<IIOAopAlsDriver>>> { |
| 88 | + let dev = pdev.get_device(); |
| 89 | + let parent = dev.parent().unwrap(); |
| 90 | + // SAFETY: our parent is AOP, and AopDriver is repr(transparent) for Arc<dyn Aop> |
| 91 | + let adata_ptr = unsafe { Pin::<KBox<Arc<dyn AOP>>>::borrow(parent.get_drvdata()) }; |
| 92 | + let adata = (&*adata_ptr).clone(); |
| 93 | + // SAFETY: AOP sets the platform data correctly |
| 94 | + let service = unsafe { *((*dev.as_raw()).platform_data as *const EPICService) }; |
| 95 | + let of = parent |
| 96 | + .of_node() |
| 97 | + .ok_or(EIO)? |
| 98 | + .get_child_by_name(c_str!("als")) |
| 99 | + .ok_or(EIO)?; |
| 100 | + let ty = bindings::BINDINGS_IIO_LIGHT; |
| 101 | + let data = AopSensorData::new(dev.clone(), ty, MsgProc(40))?; |
| 102 | + adata.add_fakehid_listener(service, data.clone())?; |
| 103 | + enable_als(adata.as_ref(), &dev, &of, &service)?; |
| 104 | + let info_mask = 1 << bindings::BINDINGS_IIO_CHAN_INFO_PROCESSED; |
| 105 | + Ok(KBox::pin( |
| 106 | + IIOAopAlsDriver(IIORegistration::<MsgProc>::new( |
| 107 | + data, |
| 108 | + c_str!("aop-sensors-als"), |
| 109 | + ty, |
| 110 | + info_mask, |
| 111 | + &THIS_MODULE, |
| 112 | + )?), |
| 113 | + GFP_KERNEL, |
| 114 | + )?) |
| 115 | + } |
| 116 | +} |
| 117 | + |
| 118 | +module_platform_driver! { |
| 119 | + type: IIOAopAlsDriver, |
| 120 | + name: "iio_aop_als", |
| 121 | + license: "Dual MIT/GPL", |
| 122 | + alias: ["platform:iio_aop_als"], |
| 123 | +} |
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