On Wed, 3 Oct 2018 20:59:53 +0200 Boris Brezillon <boris.brezillon@xxxxxxxxxxx> wrote: > On Wed, 03 Oct 2018 11:37:17 -0700 > Joe Perches <joe@xxxxxxxxxxx> wrote: > > > On Wed, 2018-10-03 at 15:22 +0200, Boris Brezillon wrote: > > > The reg property of devices connected to an I3C bus have 3 cells, and > > > filling them manually is not trivial. Provides macros to help doing > > > that. > > > > This patch logic seems excessively fragile. > > Keep in mind that this header is meant to be include by .dts(i) files, > not regular .c files. > > > > > > Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx> > > > Reviewed-by: Rob Herring <robh@xxxxxxxxxx> > > > --- > > > Changes in v8: > > > - None > > > > > > Changes in v5: > > > - none > > > --- > > > include/dt-bindings/i3c/i3c.h | 28 ++++++++++++++++++++++++++++ > > > 1 file changed, 28 insertions(+) > > > create mode 100644 include/dt-bindings/i3c/i3c.h > > > > > > diff --git a/include/dt-bindings/i3c/i3c.h b/include/dt-bindings/i3c/i3c.h > > > new file mode 100644 > > > index 000000000000..97448c546649 > > > --- /dev/null > > > +++ b/include/dt-bindings/i3c/i3c.h > > > @@ -0,0 +1,28 @@ > > > +/* SPDX-License-Identifier: GPL-2.0 */ > > > +/* > > > + * Copyright (C) 2017 Cadence Design Systems Inc. > > > + * > > > + * Author: Boris Brezillon <boris.brezillon@xxxxxxxxxxx> > > > + */ > > > + > > > +#ifndef _DT_BINDINGS_I3C_I3C_H > > > +#define _DT_BINDINGS_I3C_I3C_H > > > + > > > +#define IS_I2C_DEV 0x80000000 > > > + > > > +#define I2C_DEV(addr, lvr) \ > > > + (addr) (IS_I2C_DEV | (lvr)) 0x0 > > > > This looks to be missing surrounding parentheses. > > Actually it's not. The macro is supposed to declare 3 u32 integers each > of them separated by a space: > > reg = <I2C_DEV(0x34, 0x1)>; > > is translated into > > reg = <0x34 0x80000001 0x0>; > > > > > > + > > > +#define I3C_PID(manufid, partid, instid, extrainfo) \ > > > + ((manufid) << 1) \ > > > + (((partid) << 16) | ((instid) << 12) | (extrainfo)) > > > > This macro doesn't make any sense. Missing a shift and an or? > > Same here, the PID is taking 2 32-bit entries. > > Now, I agree that this is far from obvious, and if Rob is okay, I'd > like to propose a different binding to avoid having to define these > macros: > > reg = <i2c_addr_or_i3c_static_addr pid_msb pid_lsb>; > > If pid_msb and pid_lsb are 0, then the node is defining an I2C device Actually, I meant pid_msb == 0. This part of the PID is encoding the manufacturer, and I don't think 0 is a valid manufacturer (I hope it's not). So, we'd have something like: reg = <i2c_addr_or_i3c_static_addr pid_msb pid_lsb_or_i2c_lvr>; > (AFAICT, 0 is not a valid PID), otherwise it's an I3C device. This way > we get rid of the IS_I2C_DEV flag, and we can get rid of those macros > without making I3C dev node definition too painful (the only part > developers will have to get right is the PID) > > > > > > + > > > +#define I3C_DEV_WITH_STATIC_ADDR(addr, manufid, partid, \ > > > + instid, extrainfo) \ > > > + (addr) I3C_PID(manufid, partid, instid, extrainfo) > > > + > > > +#define I3C_DEV(manufid, partid, instid, extrainfo) \ > > > + I3C_DEV_WITH_STATIC_ADDR(0x0, manufid, partid, \ > > > + instid, extrainfo) > > > + > > > +#endif > > >
