soc: qcom: Add Shared Memory Driver

This adds the Qualcomm Shared Memory Driver (SMD) providing
communication channels to remote processors, ontop of SMEM.

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Andy Gross <agross@codeaurora.org>

drivers/soc/qcom/Kconfig

@@ -19,6 +19,14 @@ config QCOM_PM
 	  modes. It interface with various system drivers to put the cores in
 	  low power modes.
 
+config QCOM_SMD
+	tristate "Qualcomm Shared Memory Driver (SMD)"
+	depends on QCOM_SMEM
+	help
+	  Say y here to enable support for the Qualcomm Shared Memory Driver
+	  providing communication channels to remote processors in Qualcomm
+	  platforms.
+
 config QCOM_SMEM
 	tristate "Qualcomm Shared Memory Manager (SMEM)"
 	depends on ARCH_QCOM

drivers/soc/qcom/Makefile

@@ -1,3 +1,4 @@
 obj-$(CONFIG_QCOM_GSBI)	+=	qcom_gsbi.o
 obj-$(CONFIG_QCOM_PM)	+=	spm.o
+obj-$(CONFIG_QCOM_SMD) +=	smd.o
 obj-$(CONFIG_QCOM_SMEM) +=	smem.o

include/linux/soc/qcom/smd.h

@@ -0,0 +1,46 @@
+#ifndef __QCOM_SMD_H__
+#define __QCOM_SMD_H__
+
+#include <linux/device.h>
+#include <linux/mod_devicetable.h>
+
+struct qcom_smd;
+struct qcom_smd_channel;
+struct qcom_smd_lookup;
+
+/**
+ * struct qcom_smd_device - smd device struct
+ * @dev:	the device struct
+ * @channel:	handle to the smd channel for this device
+ */
+struct qcom_smd_device {
+	struct device dev;
+	struct qcom_smd_channel *channel;
+};
+
+/**
+ * struct qcom_smd_driver - smd driver struct
+ * @driver:	underlying device driver
+ * @probe:	invoked when the smd channel is found
+ * @remove:	invoked when the smd channel is closed
+ * @callback:	invoked when an inbound message is received on the channel,
+ *		should return 0 on success or -EBUSY if the data cannot be
+ *		consumed at this time
+ */
+struct qcom_smd_driver {
+	struct device_driver driver;
+	int (*probe)(struct qcom_smd_device *dev);
+	void (*remove)(struct qcom_smd_device *dev);
+	int (*callback)(struct qcom_smd_device *, const void *, size_t);
+};
+
+int qcom_smd_driver_register(struct qcom_smd_driver *drv);
+void qcom_smd_driver_unregister(struct qcom_smd_driver *drv);
+
+#define module_qcom_smd_driver(__smd_driver) \
+	module_driver(__smd_driver, qcom_smd_driver_register, \
+		      qcom_smd_driver_unregister)
+
+int qcom_smd_send(struct qcom_smd_channel *channel, const void *data, int len);
+
+#endif