ASoC: SOF: Intel: hda-mlink: add helper to offload link ownership

For DMIC and SSP, the DSP will be responsible for programming the
blobs and link registers.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20230404104127.5629-18-peter.ujfalusi@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

include/sound/hda-mlink.h

@@ -52,6 +52,8 @@ int hda_bus_ml_suspend(struct hdac_bus *bus);
 struct hdac_ext_link *hdac_bus_eml_ssp_get_hlink(struct hdac_bus *bus);
 struct hdac_ext_link *hdac_bus_eml_dmic_get_hlink(struct hdac_bus *bus);
 
+int hdac_bus_eml_enable_offload(struct hdac_bus *bus, bool alt, int elid, bool enable);
+
 #else
 
 static inline int
@@ -151,4 +153,9 @@ hdac_bus_eml_ssp_get_hlink(struct hdac_bus *bus) { return NULL; }
 static inline struct hdac_ext_link *
 hdac_bus_eml_dmic_get_hlink(struct hdac_bus *bus) { return NULL; }
 
+static inline int
+hdac_bus_eml_enable_offload(struct hdac_bus *bus, bool alt, int elid, bool enable)
+{
+	return 0;
+}
 #endif /* CONFIG_SND_SOC_SOF_HDA */

sound/soc/sof/intel/hda-mlink.c

@@ -333,6 +333,18 @@ static void hdaml_link_set_lsdiid(u32 __iomem *lsdiid, int dev_num)
 	writel(val, lsdiid);
 }
 
+static void hdaml_lctl_offload_enable(u32 __iomem *lctl, bool enable)
+{
+	u32 val = readl(lctl);
+
+	if (enable)
+		val |=  AZX_ML_LCTL_OFLEN;
+	else
+		val &=  ~AZX_ML_LCTL_OFLEN;
+
+	writel(val, lctl);
+}
+
 /* END HDAML section */
 
 static int hda_ml_alloc_h2link(struct hdac_bus *bus, int index)
@@ -812,6 +824,30 @@ struct hdac_ext_link *hdac_bus_eml_dmic_get_hlink(struct hdac_bus *bus)
 }
 EXPORT_SYMBOL_NS(hdac_bus_eml_dmic_get_hlink, SND_SOC_SOF_HDA_MLINK);
 
+int hdac_bus_eml_enable_offload(struct hdac_bus *bus, bool alt, int elid, bool enable)
+{
+	struct hdac_ext2_link *h2link;
+	struct hdac_ext_link *hlink;
+
+	h2link = find_ext2_link(bus, alt, elid);
+	if (!h2link)
+		return -ENODEV;
+
+	if (!h2link->ofls)
+		return 0;
+
+	hlink = &h2link->hext_link;
+
+	mutex_lock(&h2link->eml_lock);
+
+	hdaml_lctl_offload_enable(hlink->ml_addr + AZX_REG_ML_LCTL, enable);
+
+	mutex_unlock(&h2link->eml_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_NS(hdac_bus_eml_enable_offload, SND_SOC_SOF_HDA_MLINK);
+
 #endif
 
 MODULE_LICENSE("Dual BSD/GPL");