stm32/rcc: add LSE/LSI to all chips, add RTC to more chips.

embassy-stm32/src/rcc/f7.rs

@@ -1,16 +1,12 @@
 use crate::pac::pwr::vals::Vos;
 use crate::pac::rcc::vals::{Hpre, Pllm, Plln, Pllp, Pllq, Pllsrc, Ppre, Sw};
 use crate::pac::{FLASH, PWR, RCC};
-use crate::rcc::bd::{BackupDomain, RtcClockSource};
 use crate::rcc::{set_freqs, Clocks};
 use crate::time::Hertz;
 
 /// HSI speed
 pub const HSI_FREQ: Hertz = Hertz(16_000_000);
 
-/// LSI speed
-pub const LSI_FREQ: Hertz = Hertz(32_000);
-
 /// Clocks configuration
 #[non_exhaustive]
 #[derive(Default)]
@@ -23,9 +19,7 @@ pub struct Config {
     pub pclk2: Option<Hertz>,
 
     pub pll48: bool,
-    pub rtc: Option<RtcClockSource>,
-    pub lsi: bool,
-    pub lse: Option<Hertz>,
+    pub ls: super::LsConfig,
 }
 
 fn setup_pll(pllsrcclk: u32, use_hse: bool, pllsysclk: Option<u32>, pll48clk: bool) -> PllResults {
@@ -261,17 +255,7 @@ pub(crate) unsafe fn init(config: Config) {
         })
     });
 
-    BackupDomain::configure_ls(
-        config.rtc.unwrap_or(RtcClockSource::NOCLOCK),
-        config.lsi,
-        config.lse.map(|_| Default::default()),
-    );
-
-    let rtc = match config.rtc {
-        Some(RtcClockSource::LSI) => Some(LSI_FREQ),
-        Some(RtcClockSource::LSE) => Some(config.lse.unwrap()),
-        _ => None,
-    };
+    let rtc = config.ls.init();
 
     set_freqs(Clocks {
         sys: Hertz(sysclk),