Re: [PATCH v2] usb: misc: add USB251xB/xBi Hi-Speed Hub Controller Driver

From: Greg KH
Date: Sun Feb 05 2017 - 02:42:40 EST


On Fri, Feb 03, 2017 at 11:55:24AM +0100, Richard Leitner wrote:
> +/**
> + * ascii2utf16le() - Helper routine for producing UTF-16LE string descriptors
> + * @s: Null-terminated ASCII (actually ISO-8859-1) string
> + * @buf: Buffer for UTF-16LE string
> + * @len: Length (in bytes; may be odd) of UTF-16LE buffer.
> + *
> + * Return: The number of bytes filled in: 2*strlen(s) or @len, whichever is less
> + *
> + * Note:
> + * The UTF-16LE USB String descriptors can contain at most 31 characters (as
> + * specified in the datasheet); input strings longer than that are truncated.
> + *
> + * Based on ascii2desc from drivers/usb/core/hcd.c
> + */
> +static unsigned int ascii2utf16le(char const *s, u8 *buf, unsigned int len)
> +{
> + unsigned int n, t = 2 * strlen(s);
> +
> + if (t > USB251XB_STRING_BUFSIZE)
> + t = USB251XB_STRING_BUFSIZE;
> + if (len > t)
> + len = t;
> + n = len;
> + while (n--) {
> + t = (unsigned char)*s++;
> + *buf++ = t;
> + if (!n--)
> + break;
> + *buf++ = t >> 8;
> + }
> + return len;
> +}

Don't we have a kernel function for this already? If we need to export
ascii2desc() from the USB core, we can do that, or better yet, move both
of them to a string library function in the core part of the kernel. We
shouldn't have to duplicate this type of thin in an individual driver.

> --- /dev/null
> +++ b/include/linux/platform_data/usb251xb.h
> @@ -0,0 +1,33 @@
> +#ifndef __USB251XB_H__
> +#define __USB251XB_H__
> +
> +struct usb251xb_platform_data {
> + int gpio_reset;
> + u16 vendor_id;
> + u16 product_id;
> + u16 device_id;
> + u8 conf_data1;
> + u8 conf_data2;
> + u8 conf_data3;
> + u8 non_rem_dev;
> + u8 port_disable_sp;
> + u8 port_disable_bp;
> + u8 max_power_sp;
> + u8 max_power_bp;
> + u8 max_current_sp;
> + u8 max_current_bp;
> + u8 power_on_time;
> + u16 lang_id;
> + char manufacturer[31]; /* NULL terminated ASCII string */
> + char product[31]; /* NULL terminated ASCII string */
> + char serial[31]; /* NULL terminated ASCII string */
> + u8 bat_charge_en;
> + u8 boost_up;
> + u8 boost_x;
> + u8 port_swap;
> + u8 port_map12;
> + u8 port_map34;
> + u8 status;
> +};

Do you need a platform data structure here? Shouldn't we be only using
DT now?

thanks,

greg k-h