soundwire: bus: Allow SoundWire peripherals to register IRQ handlers

Currently the in-band alerts for SoundWire peripherals can only
be communicated to the driver through the interrupt_callback
function. This however is slightly inconvenient for devices that wish
to share IRQ handling code between SoundWire and I2C/SPI, the later
would normally register an IRQ handler with the IRQ subsystem. However
there is no reason the SoundWire in-band IRQs can not also be
communicated as an actual IRQ to the driver.

Add support for SoundWire peripherals to register a normal IRQ
handler to receive SoundWire in-band alerts, allowing code to be
shared across control buses. Note that we allow users to use both the
interrupt_callback and the IRQ handler, this is useful for devices
which must clear additional chip specific SoundWire registers that are
not a part of the normal IRQ flow, or the SoundWire specification.

Signed-off-by: Lucas Tanure <tanureal@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Acked-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230804104602.395892-2-ckeepax@opensource.cirrus.com
Signed-off-by: Lee Jones <lee@kernel.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h
index f523ceabd059..8923387a7405 100644
--- a/include/linux/soundwire/sdw.h
+++ b/include/linux/soundwire/sdw.h
@@ -6,6 +6,8 @@
 
 #include <linux/bug.h>
 #include <linux/lockdep_types.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/mod_devicetable.h>
 #include <linux/bitfield.h>
 
@@ -370,6 +372,7 @@ struct sdw_dpn_prop {
  * @clock_reg_supported: the Peripheral implements the clock base and scale
  * registers introduced with the SoundWire 1.2 specification. SDCA devices
  * do not need to set this boolean property as the registers are required.
+ * @use_domain_irq: call actual IRQ handler on slave, as well as callback
  */
 struct sdw_slave_prop {
 	u32 mipi_revision;
@@ -394,6 +397,7 @@ struct sdw_slave_prop {
 	u8 scp_int1_mask;
 	u32 quirks;
 	bool clock_reg_supported;
+	bool use_domain_irq;
 };
 
 #define SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY	BIT(0)
@@ -641,6 +645,7 @@ struct sdw_slave_ops {
  * struct sdw_slave - SoundWire Slave
  * @id: MIPI device ID
  * @dev: Linux device
+ * @irq: IRQ number
  * @status: Status reported by the Slave
  * @bus: Bus handle
  * @prop: Slave properties
@@ -670,6 +675,7 @@ struct sdw_slave_ops {
 struct sdw_slave {
 	struct sdw_slave_id id;
 	struct device dev;
+	int irq;
 	enum sdw_slave_status status;
 	struct sdw_bus *bus;
 	struct sdw_slave_prop prop;
@@ -885,6 +891,7 @@ struct sdw_master_ops {
  * is used to compute and program bus bandwidth, clock, frame shape,
  * transport and port parameters
  * @debugfs: Bus debugfs
+ * @domain: IRQ domain
  * @defer_msg: Defer message
  * @clk_stop_timeout: Clock stop timeout computed
  * @bank_switch_timeout: Bank switch timeout computed
@@ -920,6 +927,8 @@ struct sdw_bus {
 #ifdef CONFIG_DEBUG_FS
 	struct dentry *debugfs;
 #endif
+	struct irq_chip irq_chip;
+	struct irq_domain *domain;
 	struct sdw_defer defer_msg;
 	unsigned int clk_stop_timeout;
 	u32 bank_switch_timeout;