Hi Jason,
On Jun 28 2017 or thereabouts, Jason Gerecke wrote:
> The 'wacom_update_name' function is responsible for producing names for
> the input device nodes based on the hardware device name. Commit f2209d4
> added the ability to strip off prefixes like "Wacom Co.,Ltd." where the
> prefix was immediately (and redundantly) followed by "Wacom". The
> 2nd-generation Intuos Pro 2 has such a prefix, but with a small error
> (the period and comma are swapped) that prevents the existing code from
> matching it. We're loath to extend the number of cases out endlessly and
> so instead try to be smarter about name generation.
>
> We observe that the cause of the redundant prefixes is HID combining the
> manufacturer and product strings of USB devices together. By using the
> original product name (with "Wacom" prefixed, if it does not already
> exist in the string) we can bypass the gyrations to find and remove
> redundant prefixes. Other devices either don't have a manufacturer string
> that needs to be removed (Bluetooth, uhid) or should have their name
> generated from scratch (I2C).
>
Sorry for nitpicking, but I have a couple of comments:
> Signed-off-by: Jason Gerecke <jason.gerecke@xxxxxxxxx>
> ---
> Changes from v2:
> * Use export/extern to directly gain access to the usb_hid_driver struct
> for comparison to ll_driver (rather than scanning through the list of
> USB devices for a matching parent).
>
> drivers/hid/usbhid/hid-core.c | 1 +
> drivers/hid/wacom_sys.c | 60 +++++++++++++++++++++----------------------
> 2 files changed, 30 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
> index 83772fa7d92a..4a7a306995a9 100644
> --- a/drivers/hid/usbhid/hid-core.c
> +++ b/drivers/hid/usbhid/hid-core.c
> @@ -1269,6 +1269,7 @@ static struct hid_ll_driver usb_hid_driver = {
> .output_report = usbhid_output_report,
> .idle = usbhid_idle,
> };
> +EXPORT_SYMBOL_GPL(usb_hid_driver);
I would rather see this in a separate commit (in case we need to revert
this one, we shouldn't revert the export).
>
> static int usbhid_probe(struct usb_interface *intf, const struct usb_device_id *id)
> {
> diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
> index 0022c0dac88a..94d493c724c8 100644
> --- a/drivers/hid/wacom_sys.c
> +++ b/drivers/hid/wacom_sys.c
> @@ -22,6 +22,8 @@
> #define DEV_ATTR_WO_PERM (S_IWUSR | S_IWGRP)
> #define DEV_ATTR_RO_PERM (S_IRUSR | S_IRGRP)
>
> +extern struct hid_ll_driver usb_hid_driver;
Ouch. I'd rather see that one in drivers/hid/usbhid/usbhid.h
I would like also to have the following in usbhid.h, that you can reuse
later in the patch:
static inline bool hid_is_using_usbhid(struct hid_device *hdev)
{
return hdev->ll_driver == &usb_hid_driver;
}
> +
> static int wacom_get_report(struct hid_device *hdev, u8 type, u8 *buf,
> size_t size, unsigned int retries)
> {
> @@ -2026,41 +2028,37 @@ static void wacom_update_name(struct wacom *wacom, const char *suffix)
>
> /* Generic devices name unspecified */
> if ((features->type == HID_GENERIC) && !strcmp("Wacom HID", features->name)) {
> - if (strstr(wacom->hdev->name, "Wacom") ||
> - strstr(wacom->hdev->name, "wacom") ||
> - strstr(wacom->hdev->name, "WACOM")) {
> - /* name is in HID descriptor, use it */
> - strlcpy(name, wacom->hdev->name, sizeof(name));
> -
> - /* strip out excess whitespaces */
> - while (1) {
> - char *gap = strstr(name, " ");
> - if (gap == NULL)
> - break;
> - /* shift everything including the terminator */
> - memmove(gap, gap+1, strlen(gap));
> - }
> + char *product_name = wacom->hdev->name;
>
> - /* strip off excessive prefixing */
> - if (strstr(name, "Wacom Co.,Ltd. Wacom ") == name) {
> - int n = strlen(name);
> - int x = strlen("Wacom Co.,Ltd. ");
> - memmove(name, name+x, n-x+1);
> - }
> - if (strstr(name, "Wacom Co., Ltd. Wacom ") == name) {
> - int n = strlen(name);
> - int x = strlen("Wacom Co., Ltd. ");
> - memmove(name, name+x, n-x+1);
> - }
> + if (wacom->hdev->ll_driver == &usb_hid_driver) {
> + struct usb_interface *intf = to_usb_interface(wacom->hdev->dev.parent);
> + struct usb_device *dev = interface_to_usbdev(intf);
> + product_name = dev->product;
> + }
>
> - /* get rid of trailing whitespace */
> - if (name[strlen(name)-1] == ' ')
> - name[strlen(name)-1] = '\0';
> + if (wacom->hdev->bus == BUS_I2C) {
> + snprintf(name, sizeof(name), "%s %X",
> + features->name, wacom->hdev->product);
> + } else if (strstr(product_name, "Wacom") ||
> + strstr(product_name, "wacom") ||
> + strstr(product_name, "WACOM")) {
> + strlcpy(name, product_name, sizeof(name));
> } else {
> - /* no meaningful name retrieved. use product ID */
> - snprintf(name, sizeof(name),
> - "%s %X", features->name, wacom->hdev->product);
> + snprintf(name, sizeof(name), "Wacom %s", product_name);
> }
> +
> + /* strip out excess whitespaces */
> + while (1) {
> + char *gap = strstr(name, " ");
> + if (gap == NULL)
> + break;
> + /* shift everything including the terminator */
> + memmove(gap, gap+1, strlen(gap));
> + }
> +
> + /* get rid of trailing whitespace */
> + if (name[strlen(name)-1] == ' ')
> + name[strlen(name)-1] = '\0';
> } else {
> strlcpy(name, features->name, sizeof(name));
> }
> --
> 2.13.1
>
Rest looks good to me.
Cheers,
Benjamin
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