From d92b91576e3787659917f32d514de8c4d75631b4 Mon Sep 17 00:00:00 2001 From: "Geoffrey D. Bennett" Date: Tue, 22 Jun 2021 03:39:31 +0930 Subject: [PATCH] ALSA: usb-audio: scarlett2: Improve device info lookup Add the USB device ID to the scarlett2_device_info struct so that the switch statement which finds the appropriate struct can be replaced with a loop that looks through an array of pointers to those structs. Suggested-by: Vladimir Sadovnikov Signed-off-by: Geoffrey D. Bennett Link: https://lore.kernel.org/r/474c408c29fb280a611e47e49e59ca2fb9810d27.1624294591.git.g@b4.vu Signed-off-by: Takashi Iwai --- sound/usb/mixer_scarlett_gen2.c | 37 ++++++++++++++++++++------------- 1 file changed, 23 insertions(+), 14 deletions(-) diff --git a/sound/usb/mixer_scarlett_gen2.c b/sound/usb/mixer_scarlett_gen2.c index 4a36181e61ab..481ebdd1a0df 100644 --- a/sound/usb/mixer_scarlett_gen2.c +++ b/sound/usb/mixer_scarlett_gen2.c @@ -217,6 +217,7 @@ struct scarlett2_ports { }; struct scarlett2_device_info { + u32 usb_id; /* USB device identifier */ u8 line_out_hw_vol; /* line out hw volume is sw controlled */ u8 level_input_count; /* inputs with level selectable */ u8 pad_input_count; /* inputs with pad selectable */ @@ -257,6 +258,8 @@ struct scarlett2_data { /*** Model-specific data ***/ static const struct scarlett2_device_info s6i6_gen2_info = { + .usb_id = USB_ID(0x1235, 0x8203), + /* The first two analogue inputs can be switched between line * and instrument levels. */ @@ -310,6 +313,8 @@ static const struct scarlett2_device_info s6i6_gen2_info = { }; static const struct scarlett2_device_info s18i8_gen2_info = { + .usb_id = USB_ID(0x1235, 0x8204), + /* The first two analogue inputs can be switched between line * and instrument levels. */ @@ -371,6 +376,8 @@ static const struct scarlett2_device_info s18i8_gen2_info = { }; static const struct scarlett2_device_info s18i20_gen2_info = { + .usb_id = USB_ID(0x1235, 0x8201), + /* The analogue line outputs on the 18i20 can be switched * between software and hardware volume control */ @@ -437,6 +444,16 @@ static const struct scarlett2_device_info s18i20_gen2_info = { }, }; +static const struct scarlett2_device_info *scarlett2_devices[] = { + /* Supported Gen 2 devices */ + &s6i6_gen2_info, + &s18i8_gen2_info, + &s18i20_gen2_info, + + /* End of list */ + NULL +}; + /* get the starting port index number for a given port type/direction */ static int scarlett2_get_port_start_num(const struct scarlett2_ports *ports, int direction, int port_type) @@ -2293,26 +2310,18 @@ static int snd_scarlett_gen2_controls_create(struct usb_mixer_interface *mixer, int snd_scarlett_gen2_init(struct usb_mixer_interface *mixer) { struct snd_usb_audio *chip = mixer->chip; - const struct scarlett2_device_info *info; + const struct scarlett2_device_info **info = scarlett2_devices; int err; /* only use UAC_VERSION_2 */ if (!mixer->protocol) return 0; - switch (chip->usb_id) { - case USB_ID(0x1235, 0x8203): - info = &s6i6_gen2_info; - break; - case USB_ID(0x1235, 0x8204): - info = &s18i8_gen2_info; - break; - case USB_ID(0x1235, 0x8201): - info = &s18i20_gen2_info; - break; - default: /* device not (yet) supported */ + /* find device in scarlett2_devices */ + while (*info && (*info)->usb_id != chip->usb_id) + info++; + if (!*info) return -EINVAL; - } if (!(chip->setup & SCARLETT2_ENABLE)) { usb_audio_info(chip, @@ -2329,7 +2338,7 @@ int snd_scarlett_gen2_init(struct usb_mixer_interface *mixer) "Focusrite Scarlett Gen 2 Mixer Driver enabled pid=0x%04x", USB_ID_PRODUCT(chip->usb_id)); - err = snd_scarlett_gen2_controls_create(mixer, info); + err = snd_scarlett_gen2_controls_create(mixer, *info); if (err < 0) usb_audio_err(mixer->chip, "Error initialising Scarlett Mixer Driver: %d",