sdio: add set timing method

Adds the `Timing` struct to represent SDIO timing settings.

Adds a method to set low-level timing configuration for the SDIO
peripheral.

Author: rmsyn

esp-hal/src/sdio.rs

@@ -27,6 +27,7 @@ mod pins;
 mod slc;
 mod slchost;
 mod state;
+mod timing;
 
 pub use config::Config;
 pub use hinf::{AnyHinf, HinfInfo, HinfInstance};
@@ -35,6 +36,7 @@ pub use pins::Pins;
 pub use slc::{AnySlc, SlcInfo, SlcInstance};
 pub use slchost::{AnySlchost, SlchostInfo, SlchostInstance};
 pub use state::State;
+pub use timing::Timing;
 
 /// SDIO peripheral instance.
 pub trait PeripheralInstance: crate::private::Sealed {
@@ -192,6 +194,7 @@ impl<'d> Sdio<'d> {
     pub(crate) fn hardware_init(&mut self) -> Result<(), Error> {
         self.low_level_init()?;
         self.low_level_enable_hs()?;
+        self.low_level_set_timing()?;
 
         Err(Error::unimplemented())
     }
@@ -226,7 +229,48 @@ impl<'d> Sdio<'d> {
         let hinf = unsafe { &*self.hinf.info().register_block };
 
         hinf.cfg_data1()
-            .modify(|_, w| w.highspeed_enable().variant(self.config.hs));
+            .modify(|_, w| w.highspeed_enable().variant(self.config.hs()));
+
+        Ok(())
+    }
+
+    fn low_level_set_timing(&mut self) -> Result<(), Error> {
+        let host = unsafe { &*self.slchost.info().register_block };
+
+        match self.config.timing() {
+            Timing::PsendPsample => {
+                host.conf().modify(|_, w| unsafe {
+                    w.frc_sdio20().bits(0x1f);
+                    w.frc_sdio11().bits(0x0);
+                    w.frc_pos_samp().bits(0x1f);
+                    w.frc_neg_samp().bits(0x0)
+                });
+            }
+            Timing::PsendNsample => {
+                host.conf().modify(|_, w| unsafe {
+                    w.frc_sdio20().bits(0x1f);
+                    w.frc_sdio11().bits(0x0);
+                    w.frc_pos_samp().bits(0x0);
+                    w.frc_neg_samp().bits(0x1f)
+                });
+            }
+            Timing::NsendPsample => {
+                host.conf().modify(|_, w| unsafe {
+                    w.frc_sdio20().bits(0x0);
+                    w.frc_sdio11().bits(0x1f);
+                    w.frc_pos_samp().bits(0x1f);
+                    w.frc_neg_samp().bits(0x0)
+                });
+            }
+            Timing::NsendNsample => {
+                host.conf().modify(|_, w| unsafe {
+                    w.frc_sdio20().bits(0x0);
+                    w.frc_sdio11().bits(0x1f);
+                    w.frc_pos_samp().bits(0x0);
+                    w.frc_neg_samp().bits(0x1f)
+                });
+            }
+        }
 
         Ok(())
     }

esp-hal/src/sdio/config.rs

@@ -1,15 +1,50 @@
+use super::Timing;
+
 /// Represents SDIO configuration parameters.
 #[repr(C)]
 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
 pub struct Config {
-    /// Indicates support for high-speed mode.
-    pub hs: bool,
+    hs: bool,
+    timing: Timing,
 }
 
 impl Config {
     /// Creates a new [Config].
     pub const fn new() -> Self {
-        Self { hs: false }
+        Self {
+            hs: false,
+            timing: Timing::new(),
+        }
+    }
+
+    /// Gets the highspeed enable setting.
+    pub const fn hs(&self) -> bool {
+        self.hs
+    }
+
+    /// Sets the highspeed enable setting.
+    pub fn set_hs(&mut self, hs: bool) {
+        self.hs = hs;
+    }
+
+    /// Builder funciton that sets the highspeed enable setting.
+    pub fn with_hs(self, hs: bool) -> Self {
+        Self { hs, ..self }
+    }
+
+    /// Gets the timing setting.
+    pub const fn timing(&self) -> Timing {
+        self.timing
+    }
+
+    /// Sets the timing setting.
+    pub fn set_timing(&mut self, timing: Timing) {
+        self.timing = timing;
+    }
+
+    /// Builder funciton that sets the timing setting.
+    pub fn with_timing(self, timing: Timing) -> Self {
+        Self { timing, ..self }
     }
 }
 

esp-hal/src/sdio/timing.rs

@@ -0,0 +1,26 @@
+/// Represents SDIO device timing settings.
+#[repr(u8)]
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum Timing {
+    /// Send at posedge, and sample at posedge. Default for HS.
+    PsendPsample = 0,
+    /// Send at negedge, and sample at posedge. Default for DS.
+    NsendPsample,
+    /// Send at posedge, and sample at negedge.
+    PsendNsample,
+    /// Send at negedge, and sample at negedge.
+    NsendNsample,
+}
+
+impl Timing {
+    /// Creates a new [Timing].
+    pub const fn new() -> Self {
+        Self::PsendPsample
+    }
+}
+
+impl Default for Timing {
+    fn default() -> Self {
+        Self::new()
+    }
+}