On Tue, Dec 29, 2020 at 10:59 AM Barnabás Pőcze <pobrn@xxxxxxxxxxxxxx> wrote: > > 2020. december 28., hétfő 22:26 keltezéssel, Roderick Colenbrander írta: > > > [...] > > > > +/* Create a DualSense/DualShock4 RGB lightbar represented by a multicolor LED. */ > > > > +static struct led_classdev_mc *ps_lightbar_create(struct ps_device *ps_dev, > > > > + int (*brightness_set)(struct led_classdev *, enum led_brightness)) > > > > +{ > > > > + struct hid_device *hdev = ps_dev->hdev; > > > > + struct led_classdev_mc *lightbar_mc_dev; > > > > + struct mc_subled *mc_led_info; > > > > + struct led_classdev *led_cdev; > > > > + int ret; > > > > + > > > > + lightbar_mc_dev = devm_kzalloc(&hdev->dev, sizeof(*lightbar_mc_dev), GFP_KERNEL); > > > > + if (!lightbar_mc_dev) > > > > + return ERR_PTR(-ENOMEM); > > > > + > > > > + mc_led_info = devm_kzalloc(&hdev->dev, 3*sizeof(*mc_led_info), GFP_KERNEL); > > > > + if (!mc_led_info) > > > > + return ERR_PTR(-ENOMEM); > > > > + > > > > > > Is there any reason why these are dynamically allocated? > > > > No particular reason. I should probably at least not dynamically > > allocate 'mc_dev' and pass it in similar to regular LED registration > > (previously I had my regular LEDs dynamically allocated). The > > mc_led_info I will probably keep dynamic. It feels a bit nasty to have > > the caller be aware of these internal details. > > [...] > > Could you please elaborate what you mean by "It feels a bit nasty to have > the caller be aware of these internal details."? I don't think I fully understand > what you're referring to. > Maybe I misunderstood your original comment. The question was why both 'lightbar_mc_dev' and 'mc_led_info' were dynamically allocated. I interpreted it as getting rid of some of the dynamic allocation as some wasn't needed, but not sure what you had in mind. The code now looks like: struct dualsense { ... /* RGB lightbar */ struct led_classdev_mc lightbar; (not a pointer anymore) } static int ps_lightbar_register(struct ps_device *ps_dev, struct led_classdev_mc *lightbar_mc_dev, int (*brightness_set)(struct led_classdev *, enum led_brightness)) { struct hid_device *hdev = ps_dev->hdev; struct mc_subled *mc_led_info; struct led_classdev *led_cdev; int ret; mc_led_info = devm_kzalloc(&hdev->dev, 3*sizeof(*mc_led_info), GFP_KERNEL); if (!mc_led_info) return -ENOMEM; mc_led_info[0].color_index = LED_COLOR_ID_RED; ... In here I kept 'mc_led_info' as dynamically allocated. I didn't think it made sense to have the caller know about it. What was your original idea? Regards, Roderick