slimbus: ngd: Add qcom SLIMBus NGD driver

This patch adds suppor to Qualcomm SLIMBus Non-Generic Device (NGD)
controller driver.
This is light-weight SLIMBus controller driver responsible for
communicating with slave HW directly over the bus using messaging
interface, and communicating with master component residing on ADSP
for bandwidth and data-channel management

Based on intial work from
Karthikeyan Ramasubramanian <kramasub@codeaurora.org> and
Sagar Dharia <sdharia@codeaurora.org>

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Tested-by: Craig Tatlor <ctatlor97@gmail.com>
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/slimbus/Kconfig

@@ -20,4 +20,15 @@ config SLIM_QCOM_CTRL
 	  Select driver if Qualcomm's SLIMbus Manager Component is
 	  programmed using Linux kernel.
 
+config SLIM_QCOM_NGD_CTRL
+	tristate "Qualcomm SLIMbus Satellite Non-Generic Device Component"
+	depends on QCOM_QMI_HELPERS
+	depends on HAS_IOMEM && DMA_ENGINE
+	help
+	  Select driver if Qualcomm's SLIMbus Satellite Non-Generic Device
+	  Component is programmed using Linux kernel.
+	  This is light-weight slimbus controller driver responsible for
+	  communicating with slave HW directly over the bus using messaging
+	  interface, and communicating with master component residing on ADSP
+	  for bandwidth and data-channel management.
 endif

drivers/slimbus/Makefile

@@ -8,3 +8,6 @@ slimbus-y				:= core.o messaging.o sched.o
 #Controllers
 obj-$(CONFIG_SLIM_QCOM_CTRL)		+= slim-qcom-ctrl.o
 slim-qcom-ctrl-y			:= qcom-ctrl.o
+
+obj-$(CONFIG_SLIM_QCOM_NGD_CTRL)	+= slim-qcom-ngd-ctrl.o
+slim-qcom-ngd-ctrl-y			:= qcom-ngd-ctrl.o

drivers/slimbus/slimbus.h

@@ -17,6 +17,8 @@
 
 /* SLIMbus message types. Related to interpretation of message code. */
 #define SLIM_MSG_MT_CORE			0x0
+#define SLIM_MSG_MT_DEST_REFERRED_USER		0x2
+#define SLIM_MSG_MT_SRC_REFERRED_USER		0x6
 
 /*
  * SLIM Broadcast header format
@@ -48,6 +50,12 @@
 #define SLIM_MSG_MC_NEXT_PAUSE_CLOCK             0x4A
 #define SLIM_MSG_MC_RECONFIGURE_NOW              0x5F
 
+/*
+ * Clock pause flag to indicate that the reconfig message
+ * corresponds to clock pause sequence
+ */
+#define SLIM_MSG_CLK_PAUSE_SEQ_FLG		(1U << 8)
+
 /* Clock pause values per SLIMbus spec */
 #define SLIM_CLK_FAST				0
 #define SLIM_CLK_CONST_PHASE			1