Subject: Re: [PATCH net-next 03/19] net: usb: aqc111: Add implementation of read and write commands

From: Oliver Neukum <[email-masked]>
Date: Mon, 08 Oct 2018 15:44:39 +0200

On Fr, 2018-10-05 at 10:24 +0000, Igor Russkikh wrote:
> From: Dmitry Bezrukov <[email-masked]>
> 
> Read/write command register defines and functions
> 
> Signed-off-by: Dmitry Bezrukov <[email-masked]>
> Signed-off-by: Igor Russkikh <[email-masked]>
> ---
>  drivers/net/usb/aqc111.c | 124 +++++++++++++++++++++++++++++++++++++++++++++++
>  drivers/net/usb/aqc111.h |  19 ++++++++
>  2 files changed, 143 insertions(+)
>  create mode 100644 drivers/net/usb/aqc111.h
> 
> diff --git a/drivers/net/usb/aqc111.c b/drivers/net/usb/aqc111.c
> index c914e19387f2..7f3e5a615750 100644
> --- a/drivers/net/usb/aqc111.c
> +++ b/drivers/net/usb/aqc111.c
> @@ -14,6 +14,130 @@
>  #include <linux/usb/cdc.h>
>  #include <linux/usb/usbnet.h>
>  
> +#include "aqc111.h"
> +
> +static int __aqc111_read_cmd(struct usbnet *dev, u8 cmd, u16 value,
> +			     u16 index, u16 size, void *data, int nopm)
> +{
> +	int ret;
> +	int (*fn)(struct usbnet *dev, u8 cmd, u8 reqtype, u16 value,
> +		  u16 index, void *data, u16 size);
> +
> +	if (nopm)
> +		fn = usbnet_read_cmd_nopm;
> +	else
> +		fn = usbnet_read_cmd;

If you really want to do this, pass the function.

> +
> +	ret = fn(dev, cmd, USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
> +		 value, index, data, size);
> +	if (size == 2)
> +		le16_to_cpus(data);

That is incredibly dirty

> +
> +	if (unlikely(ret < 0))
> +		netdev_warn(dev->net,
> +			    "Failed to read(0x%x) reg index 0x%04x: %d\n",
> +			    cmd, index, ret);
> +	return ret;
> +}
> +
> +static int aqc111_read_cmd_nopm(struct usbnet *dev, u8 cmd, u16 value,
> +				u16 index, u16 size, void *data)
> +{
> +	return __aqc111_read_cmd(dev, cmd, value, index, size, data, 1);
> +}
> +
> +static int aqc111_read_cmd(struct usbnet *dev, u8 cmd, u16 value,
> +			   u16 index, u16 size, void *data)
> +{
> +	return __aqc111_read_cmd(dev, cmd, value, index, size, data, 0);
> +}
> +
> +static int __aq_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
> +			  u16 value, u16 index, const void *data, u16 size)
> +{
> +	void *buf = NULL;
> +	int err = -ENOMEM;
> +
> +	netdev_dbg(dev->net,
> +		   "%s cmd=%#x reqtype=%#x value=%#x index=%#x size=%d\n",
> +		   __func__, cmd, reqtype, value, index, size);
> +
> +	if (data) {
> +		buf = kmemdup(data, size, GFP_KERNEL);

Under which contexts is this used?

	Regards
		Oliver