Re: [PATCH v2 2/7] i3c: Add core I3C infrastructure

[Randy Dunlap <rdunlap@infradead.org>]

On 12/14/17 07:16, Boris Brezillon wrote:
> Add core infrastructure to support I3C in Linux and document it.
> 
> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
> ---
>  drivers/Kconfig                 |    2 +
>  drivers/Makefile                |    2 +-
>  drivers/i3c/Kconfig             |   24 +
>  drivers/i3c/Makefile            |    4 +
>  drivers/i3c/core.c              |  573 ++++++++++++++++
>  drivers/i3c/device.c            |  344 ++++++++++
>  drivers/i3c/internals.h         |   34 +
>  drivers/i3c/master.c            | 1433 +++++++++++++++++++++++++++++++++++++++
>  drivers/i3c/master/Kconfig      |    0
>  drivers/i3c/master/Makefile     |    0
>  include/linux/i3c/ccc.h         |  380 +++++++++++
>  include/linux/i3c/device.h      |  321 +++++++++
>  include/linux/i3c/master.h      |  564 +++++++++++++++
>  include/linux/mod_devicetable.h |   17 +
>  14 files changed, 3697 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/i3c/Kconfig
>  create mode 100644 drivers/i3c/Makefile
>  create mode 100644 drivers/i3c/core.c
>  create mode 100644 drivers/i3c/device.c
>  create mode 100644 drivers/i3c/internals.h
>  create mode 100644 drivers/i3c/master.c
>  create mode 100644 drivers/i3c/master/Kconfig
>  create mode 100644 drivers/i3c/master/Makefile
>  create mode 100644 include/linux/i3c/ccc.h
>  create mode 100644 include/linux/i3c/device.h
>  create mode 100644 include/linux/i3c/master.h
> 
> diff --git a/drivers/i3c/Kconfig b/drivers/i3c/Kconfig
> new file mode 100644
> index 000000000000..cf3752412ae9
> --- /dev/null
> +++ b/drivers/i3c/Kconfig
> @@ -0,0 +1,24 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +menuconfig I3C
> +	tristate "I3C support"
> +	select I2C
> +	help
> +	  I3C is a serial protocol standardized by the MIPI alliance.
> +
> +	  It's supposed to be backward compatible with I2C while providing
> +	  support for high speed transfers and native interrupt support
> +	  without the need for extra pins.
> +
> +	  The I3C protocol also standardizes the slave device types and is
> +	  mainly design to communicate with sensors.
> +
> +	  If you want I3C support, you should say Y here and also to the
> +	  specific driver for your bus adapter(s) below.
> +
> +	  This I3C support can also be built as a module.  If so, the module
> +	  will be called i3c.
> +
> +if I3C
> +source "drivers/i3c/master/Kconfig"
> +endif # I3C

> diff --git a/drivers/i3c/core.c b/drivers/i3c/core.c
> new file mode 100644
> index 000000000000..7eb8e84acd33
> --- /dev/null
> +++ b/drivers/i3c/core.c
> @@ -0,0 +1,573 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2017 Cadence Design Systems Inc.
> + *
> + * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
> + */
> +
> +#include <linux/idr.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/slab.h>

#include <linux/device.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/rwsem.h>


> +#include "internals.h"
> +
> +static DEFINE_IDR(i3c_bus_idr);
> +static DEFINE_MUTEX(i3c_core_lock);
> +

> +/**
> + * i3c_bus_maintenance_lock - Release the bus lock after a maintenance

                          unlock

> + *			      operation
> + * @bus: I3C bus to release the lock on
> + *
> + * Should be called when the bus maintenance operation is done. See
> + * i3c_bus_maintenance_lock() for more details on what these maintenance
> + * operations are.
> + */
> +void i3c_bus_maintenance_unlock(struct i3c_bus *bus)
> +{
> +	up_write(&bus->lock);
> +}
> +EXPORT_SYMBOL_GPL(i3c_bus_maintenance_unlock);
> +

> +/**
> + * i3c_bus_normaluse_lock - Release the bus lock after a normal operation

                        unlock

> + * @bus: I3C bus to release the lock on
> + *
> + * Should be called when a normal operation is done. See
> + * i3c_bus_normaluse_lock() for more details on what these normal operations
> + * are.
> + */
> +void i3c_bus_normaluse_unlock(struct i3c_bus *bus)
> +{
> +	up_read(&bus->lock);
> +}
> +EXPORT_SYMBOL_GPL(i3c_bus_normaluse_unlock);



> +static int i3c_device_match(struct device *dev, struct device_driver *drv)

bool?

> +{
> +	struct i3c_device *i3cdev;
> +	struct i3c_driver *i3cdrv;
> +
> +	if (dev->type != &i3c_device_type)
> +		return 0;
> +
> +	i3cdev = dev_to_i3cdev(dev);
> +	i3cdrv = drv_to_i3cdrv(drv);
> +	if (i3c_device_match_id(i3cdev, i3cdrv->id_table))
> +		return 1;
> +
> +	return 0;
> +}


> diff --git a/drivers/i3c/device.c b/drivers/i3c/device.c
> new file mode 100644
> index 000000000000..dcf51150b7cb
> --- /dev/null
> +++ b/drivers/i3c/device.c
> @@ -0,0 +1,344 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2017 Cadence Design Systems Inc.
> + *
> + * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
> + */
> +
> +#include <linux/slab.h>

#include <linux/atomic.h>
#include <linux/bug.h>
#include <linux/completion.h>
#include <linux/device.h>
#include <linux/mutex.h>

> +#include "internals.h"



> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> new file mode 100644
> index 000000000000..1c85abac08d5
> --- /dev/null
> +++ b/drivers/i3c/master.c
> @@ -0,0 +1,1433 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2017 Cadence Design Systems Inc.
> + *
> + * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
> + */

#include <linux/atomic.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/of.h>

> +#include <linux/slab.h>

#include <linux/spinlock.h>
#include <linux/workqueue.h>

#include <asm-generic/bug.h>

> +#include "internals.h"


and I probably missed a few.




> diff --git a/include/linux/i3c/ccc.h b/include/linux/i3c/ccc.h
> new file mode 100644
> index 000000000000..ff3e1a3e2c4c
> --- /dev/null
> +++ b/include/linux/i3c/ccc.h
> @@ -0,0 +1,380 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2017 Cadence Design Systems Inc.
> + *
> + * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
> + */

> +/**
> + * struct i3c_ccc_dev_desc - I3C/I3C device descriptor used for DEFSLVS

Is one of those I3C above supposed to be I2C?

> + *
> + * @dyn_addr: dynamic address assigned to the I3C slave or 0 if the entry is
> + *	      describing an I2C slave.
> + * @dcr: DCR value (not applicable to entries describing I2C devices)
> + * @lvr: LVR value (not applicable to entries describing I3C devices)
> + * @bcr: BCR value or 0 if this entry is describing an I2C slave
> + * @static_addr: static address or 0 if the device does not have a static
> + *		 address
> + *
> + * The DEFSLVS command should be passed an array of i3c_ccc_dev_desc
> + * descriptors (one entry per I3C/I2C dev controlled by the master).
> + */
> +struct i3c_ccc_dev_desc {
> +	u8 dyn_addr;
> +	union {
> +		u8 dcr;
> +		u8 lvr;
> +	};
> +	u8 bcr;
> +	u8 static_addr;
> +} __packed;


Needs bitops.h

> diff --git a/include/linux/i3c/device.h b/include/linux/i3c/device.h
> new file mode 100644
> index 000000000000..83958d3a02e2
> --- /dev/null
> +++ b/include/linux/i3c/device.h
> @@ -0,0 +1,321 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2017 Cadence Design Systems Inc.
> + *
> + * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
> + */
> +
> +#ifndef I3C_DEV_H
> +#define I3C_DEV_H
> +
> +#include <linux/device.h>
> +#include <linux/i2c.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>


Needs bitops.h, kconfig.h.


> diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
> new file mode 100644
> index 000000000000..7ec9a4821bac
> --- /dev/null
> +++ b/include/linux/i3c/master.h
> @@ -0,0 +1,564 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2017 Cadence Design Systems Inc.
> + *
> + * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
> + */
> +
> +#ifndef I3C_MASTER_H
> +#define I3C_MASTER_H
> +
> +#include <linux/i2c.h>
> +#include <linux/i3c/ccc.h>
> +#include <linux/i3c/device.h>
> +#include <linux/spinlock.h>
> +
> +#define I3C_HOT_JOIN_ADDR		0x2
> +#define I3C_BROADCAST_ADDR		0x7e
> +#define I3C_MAX_ADDR			GENMASK(6, 0)
> +

Needs bitops.h, workqueue.h, rwsem.h


Needs <asm-generic/bitsperlong.h>



> diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
> index abb6dc2ebbf8..e59da92d8ac9 100644
> --- a/include/linux/mod_devicetable.h
> +++ b/include/linux/mod_devicetable.h
> @@ -442,6 +442,23 @@ struct pci_epf_device_id {
>  	kernel_ulong_t driver_data;
>  };
>  
> +/* i3c */
> +
> +#define I3C_MATCH_DCR			BIT(0)
> +#define I3C_MATCH_MANUF			BIT(1)
> +#define I3C_MATCH_PART			BIT(2)
> +#define I3C_MATCH_EXTRA_INFO		BIT(3)

Needs bitops.h.

> +struct i3c_device_id {
> +	__u8 match_flags;
> +	__u8 dcr;
> +	__u16 manuf_id;
> +	__u16 part_id;
> +	__u16 extra_info;
> +
> +	const void *data;
> +};
> +
>  /* spi */
>  
>  #define SPI_NAME_SIZE	32
> 


-- 
~Randy