On Fri, Nov 30, 2018 at 10:46:53AM +0000, Srinivas Kandagatla wrote: > This patch adds basic driver model for qualcomm fastrpc. > Each DSP rpmsg channel is represented as fastrpc channel context and > is exposed as a character driver for userspace interface. > Each compute context bank is represented as fastrpc-session-context, > which are dynamically managed by the channel context char device. > > Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx> > --- > drivers/char/Kconfig | 10 ++ > drivers/char/Makefile | 1 + > drivers/char/fastrpc.c | 337 +++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 348 insertions(+) > create mode 100644 drivers/char/fastrpc.c > > diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig > index 9d03b2ff5df6..75fd274c67df 100644 > --- a/drivers/char/Kconfig > +++ b/drivers/char/Kconfig > @@ -552,6 +552,16 @@ config ADI > and SSM (Silicon Secured Memory). Intended consumers of this > driver include crash and makedumpfile. > > +config QCOM_FASTRPC > + tristate "Qualcomm FastRPC" > + depends on ARCH_QCOM || COMPILE_TEST > + depends on RPMSG > + help > + Provides a communication mechanism that allows for clients to > + make remote method invocations across processor boundary to > + applications DSP processor. Say M if you want to enable this > + module. > + > endmenu > > config RANDOM_TRUST_CPU > diff --git a/drivers/char/Makefile b/drivers/char/Makefile > index b8d42b4e979b..30ec9187350e 100644 > --- a/drivers/char/Makefile > +++ b/drivers/char/Makefile > @@ -58,3 +58,4 @@ js-rtc-y = rtc.o > obj-$(CONFIG_XILLYBUS) += xillybus/ > obj-$(CONFIG_POWERNV_OP_PANEL) += powernv-op-panel.o > obj-$(CONFIG_ADI) += adi.o > +obj-$(CONFIG_QCOM_FASTRPC) += fastrpc.o > diff --git a/drivers/char/fastrpc.c b/drivers/char/fastrpc.c > new file mode 100644 > index 000000000000..97d8062eb3e1 > --- /dev/null > +++ b/drivers/char/fastrpc.c > @@ -0,0 +1,337 @@ > +// SPDX-License-Identifier: GPL-2.0 > +// Copyright (c) 2011-2018, The Linux Foundation. All rights reserved. > +// Copyright (c) 2018, Linaro Limited > + > +#include <linux/cdev.h> > +#include <linux/device.h> > +#include <linux/dma-mapping.h> > +#include <linux/idr.h> > +#include <linux/list.h> > +#include <linux/module.h> > +#include <linux/of_address.h> > +#include <linux/of.h> > +#include <linux/of_platform.h> > +#include <linux/rpmsg.h> > +#include <linux/scatterlist.h> > +#include <linux/slab.h> > + > +#define ADSP_DOMAIN_ID (0) > +#define MDSP_DOMAIN_ID (1) > +#define SDSP_DOMAIN_ID (2) > +#define CDSP_DOMAIN_ID (3) > +#define FASTRPC_DEV_MAX 4 /* adsp, mdsp, slpi, cdsp*/ > +#define FASTRPC_MAX_SESSIONS 9 /*8 compute, 1 cpz*/ > +#define FASTRPC_CTX_MAX (256) > +#define FASTRPC_CTXID_MASK (0xFF0) > +#define FASTRPC_DEVICE_NAME "fastrpc" > + > +#define cdev_to_cctx(d) container_of(d, struct fastrpc_channel_ctx, cdev) > + > +static const char *domains[FASTRPC_DEV_MAX] = { "adsp", "mdsp", > + "sdsp", "cdsp"}; > +static dev_t fastrpc_major; Why do you need a whole major number for this? Why not just use the misc interface instead?