[PATCH v7 03/12] drivers: i3c: Add i3c uclass driver.

[Heiko Schocher]

Hello Dinesh,

On 28.07.25 08:56, dinesh.maniyam at altera.com wrote:
> From: Dinesh Maniyam <dinesh.maniyam at altera.com>
> 
> Enable i3c general uclass driver. This uclass driver will have
> genaral read and write api to call the specific i3c driver.
> 
> Signed-off-by: Dinesh Maniyam <dinesh.maniyam at altera.com>
> ---
>   doc/api/i3c.rst          |  8 +++++
>   doc/api/index.rst        |  1 +
>   drivers/i3c/i3c-uclass.c | 38 +++++++++++++++++++++++
>   include/dw-i3c.h         |  1 +
>   include/i3c.h            | 67 ++++++++++++++++++++++++++++++++++++++++
>   5 files changed, 115 insertions(+)
>   create mode 100644 doc/api/i3c.rst
>   create mode 100644 drivers/i3c/i3c-uclass.c
>   create mode 100644 include/i3c.h
> 
> diff --git a/doc/api/i3c.rst b/doc/api/i3c.rst
> new file mode 100644
> index 00000000000..7906face080
> --- /dev/null
> +++ b/doc/api/i3c.rst
> @@ -0,0 +1,8 @@
> +.. SPDX-License-Identifier: GPL-2.0+
> +.. Copyright (C) 2025 Altera Corporation <www.altera.com>
> +
> +I3C Subsystem
> +===============
> +
> +.. kernel-doc:: include/i3c.h
> +   :internal:
> diff --git a/doc/api/index.rst b/doc/api/index.rst
> index a108718ea99..f3b6aefd854 100644
> --- a/doc/api/index.rst
> +++ b/doc/api/index.rst
> @@ -15,6 +15,7 @@ U-Boot API documentation
>      fs
>      getopt
>      interrupt
> +   i3c

please keep this list sorted.

>      led
>      linker_lists
>      lmb
> diff --git a/drivers/i3c/i3c-uclass.c b/drivers/i3c/i3c-uclass.c
> new file mode 100644
> index 00000000000..72944424c1d
> --- /dev/null
> +++ b/drivers/i3c/i3c-uclass.c
> @@ -0,0 +1,38 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2025 Altera Corporation <www.altera.com>
> + */
> +
> +#include <dm.h>
> +#include <i3c.h>
> +#include <errno.h>
> +#include <log.h>
> +#include <dm/device-internal.h>
> +#include <linux/ctype.h>
> +
> +int dm_i3c_read(struct udevice *dev, u32 dev_number,
> +		u8 *buf, u32 num_bytes)
> +{
> +	struct dm_i3c_ops *ops = i3c_get_ops(dev);
> +
> +	if (!ops->read)
> +		return -ENOSYS;
> +
> +	return ops->read(dev, dev_number, buf, num_bytes);
> +}
> +
> +int dm_i3c_write(struct udevice *dev, u32 dev_number,
> +		 u8 *buf, u32 num_bytes)
> +{
> +	struct dm_i3c_ops *ops = i3c_get_ops(dev);
> +
> +	if (!ops->write)
> +		return -ENOSYS;
> +
> +	return ops->write(dev, dev_number, buf, num_bytes);
> +}
> +
> +UCLASS_DRIVER(i3c) = {
> +	.id		= UCLASS_I3C,
> +	.name		= "i3c",
> +};
> diff --git a/include/dw-i3c.h b/include/dw-i3c.h
> index e37fd4dc325..920f18bccb4 100644
> --- a/include/dw-i3c.h
> +++ b/include/dw-i3c.h
> @@ -7,6 +7,7 @@
>   #define _DW_I3C_H_
>   
>   #include <clk.h>
> +#include <i3c.h>
>   #include <reset.h>
>   #include <dm/device.h>
>   #include <linux/bitops.h>
> diff --git a/include/i3c.h b/include/i3c.h
> new file mode 100644
> index 00000000000..59c787c21db
> --- /dev/null
> +++ b/include/i3c.h
> @@ -0,0 +1,67 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * Copyright (C) 2025 Altera Corporation <www.altera.com>
> + */
> +
> +#include <linux/i3c/master.h>
> +
> +/**
> + * struct dm_i3c_ops - Driver operations for the I3C uclass
> + *
> + * This structure defines the set of operations that a driver must implement
> + * for interacting with an I3C controller in U-Boot.
> + *
> + */
> +struct dm_i3c_ops {
> +/**
> + * @i3c_xfers: Transfer messages in I3C
> + *
> + * @dev: I3C controller device instance.
> + * @xfers: List of I3C private SDR transfer messages.
> + * @nxfers: The number of messages to transfer.
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +	int (*i3c_xfers)(struct i3c_dev_desc *dev,
> +			 struct i3c_priv_xfer *xfers,
> +			 u32 nxfers);
> +};
> +
> +/**
> + * i3c_get_ops - Retrieve the I3C operation functions for a device
> + * @dev: The I3C controller device.
> + *
> + * This macro returns the set of operation functions (`dm_i3c_ops`) implemented
> + * by the driver associated with the specified device. These operations define
> + * how the driver performs I3C communication tasks such as reading, writing,
> + * and message transfers.
> + *
> + * Return: The I3C operation structure for the device.
> + */
> +#define i3c_get_ops(dev)	((struct dm_i3c_ops *)(dev)->driver->ops)
> +
> +/**
> + * dm_i3c_write - Perform I3C write transaction
> + *
> + * @dev: Chip to write to
> + * @dev_number: The target device number from the driver model.
> + * @buf: Buffer containing data to write
> + * @num_bytes: Number of bytes to write.
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +int dm_i3c_write(struct udevice *dev, u32 dev_number,
> +		 u8 *buf, u32 num_bytes);
> +
> +/**
> + * dm_i3c_read - Perform I3C read transaction
> + *
> + * @dev: Chip to read from
> + * @dev_number: The target device number from the driver model.
> + * @buf: Place to put data
> + * @num_bytes: Number of bytes to read.
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +int dm_i3c_read(struct udevice *dev, u32 dev_number,
> +		u8 *buf, u32 num_bytes);
> \ No newline at end of file
> 

beside of the nitpick:

Reviewed-by: Heiko Schocher <hs at denx.de>

bye,
Heiko
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