Re: [PATCH v5 2/2] leds: add ktd202x driver
From: André Apitzsch
Date: Sun Oct 01 2023 - 12:56:43 EST
Hi Christophe,
Am Sonntag, dem 01.10.2023 um 17:15 +0200 schrieb Christophe JAILLET:
> Le 01/10/2023 à 15:52, André Apitzsch a écrit :
> > This commit adds support for Kinetic KTD2026/7 RGB/White LED
> > driver.
> >
> > Signed-off-by: André Apitzsch
> > <git-AtRKszJ1oGPsq35pWSNszA@xxxxxxxxxxxxxxxx>
>
> ...
>
> > +static int ktd202x_setup_led_rgb(struct ktd202x *chip, struct
> > device_node *np,
> > + struct ktd202x_led *led, struct
> > led_init_data *init_data)
> > +{
> > + struct led_classdev *cdev;
> > + struct device_node *child;
> > + struct mc_subled *info;
> > + int num_channels;
> > + int i = 0;
> > + u32 reg;
> > + int ret;
> > +
> > + num_channels = of_get_available_child_count(np);
> > + if (!num_channels || num_channels > chip->num_leds)
> > + return -EINVAL;
> > +
> > + info = devm_kcalloc(chip->dev, num_channels, sizeof(*info),
> > GFP_KERNEL);
> > + if (!info)
> > + return -ENOMEM;
> > +
> > + for_each_available_child_of_node(np, child) {
> > + u32 mono_color = 0;
>
> Un-needed init.
> And, why is it defined here, while reg is defined out-side the loop?
I'll move it out-side the loop (without initialization).
>
> > +
> > + ret = of_property_read_u32(child, "reg", ®);
> > + if (ret != 0 || reg >= chip->num_leds) {
> > + dev_err(chip->dev, "invalid 'reg' of
> > %pOFn\n", np);
>
> Mossing of_node_put(np);?
It shouldn't be needed here if handled in the calling function, right?
>
> > + return -EINVAL;
> > + }
> > +
> > + ret = of_property_read_u32(child, "color",
> > &mono_color);
> > + if (ret < 0 && ret != -EINVAL) {
> > + dev_err(chip->dev, "failed to parse 'color'
> > of %pOF\n", np);
>
> Mossing of_node_put(np);?
>
> > + return ret;
> > + }
> > +
> > + info[i].color_index = mono_color;
> > + info[i].channel = reg;
> > + info[i].intensity = KTD202X_MAX_BRIGHTNESS;
> > + i++;
> > + }
> > +
> > + led->mcdev.subled_info = info;
> > + led->mcdev.num_colors = num_channels;
> > +
> > + cdev = &led->mcdev.led_cdev;
> > + cdev->brightness_set_blocking = ktd202x_brightness_mc_set;
> > + cdev->blink_set = ktd202x_blink_mc_set;
> > +
> > + return devm_led_classdev_multicolor_register_ext(chip->dev,
> > &led->mcdev, init_data);
> > +}
> > +
> > +static int ktd202x_setup_led_single(struct ktd202x *chip, struct
> > device_node *np,
> > + struct ktd202x_led *led, struct
> > led_init_data *init_data)
> > +{
> > + struct led_classdev *cdev;
> > + u32 reg;
> > + int ret;
> > +
> > + ret = of_property_read_u32(np, "reg", ®);
> > + if (ret != 0 || reg >= chip->num_leds) {
> > + dev_err(chip->dev, "invalid 'reg' of %pOFn\n", np);
> > + return -EINVAL;
> > + }
> > + led->index = reg;
> > +
> > + cdev = &led->cdev;
> > + cdev->brightness_set_blocking =
> > ktd202x_brightness_single_set;
> > + cdev->blink_set = ktd202x_blink_single_set;
> > +
> > + return devm_led_classdev_register_ext(chip->dev, &led-
> > >cdev, init_data);
> > +}
> > +
> > +static int ktd202x_add_led(struct ktd202x *chip, struct
> > device_node *np, unsigned int index)
> > +{
> > + struct ktd202x_led *led = &chip->leds[index];
> > + struct led_init_data init_data = {};
> > + struct led_classdev *cdev;
> > + u32 color = 0;
> Un-needed init.
>
> > + int ret;
> > +
> > + /* Color property is optional in single color case */
> > + ret = of_property_read_u32(np, "color", &color);
> > + if (ret < 0 && ret != -EINVAL) {
> > + dev_err(chip->dev, "failed to parse 'color' of
> > %pOF\n", np);
> > + return ret;
> > + }
> > +
> > + led->chip = chip;
> > + init_data.fwnode = of_fwnode_handle(np);
> > +
> > + if (color == LED_COLOR_ID_RGB) {
> > + cdev = &led->mcdev.led_cdev;
> > + ret = ktd202x_setup_led_rgb(chip, np, led,
> > &init_data);
> > + } else {
> > + cdev = &led->cdev;
> > + ret = ktd202x_setup_led_single(chip, np, led,
> > &init_data);
> > + }
> > +
> > + if (ret) {
> > + dev_err(chip->dev, "unable to register %s\n", cdev-
> > >name);
> > + of_node_put(np);
>
> This is strange to have it here.
> Why not above after "if (ret < 0 && ret != -EINVAL) {"?
>
> It would look much more natural to have it a few lines below, ... [1]
Good catch. I'll move of_node_put(np); to [1] and [2].
>
> > + return ret;
> > + }
> > +
> > + cdev->max_brightness = KTD202X_MAX_BRIGHTNESS;
> > +
> > + return 0;
> > +}
> > +
> > +static int ktd202x_probe_dt(struct ktd202x *chip)
> > +{
> > + struct device_node *np = dev_of_node(chip->dev), *child;
> > + unsigned int i;
> > + int count, ret;
> > +
> > + chip->num_leds = (int)(unsigned
> > long)of_device_get_match_data(chip->dev);
> > +
> > + count = of_get_available_child_count(np);
> > + if (!count || count > chip->num_leds)
[2].
> > + return -EINVAL;
> > +
> > + regmap_write(chip->regmap, KTD202X_REG_RESET_CONTROL,
> > KTD202X_RSTR_RESET);
> > +
> > + /* Allow the device to execute the complete reset */
> > + usleep_range(200, 300);
> > +
> > + i = 0;
> > + for_each_available_child_of_node(np, child) {
> > + ret = ktd202x_add_led(chip, child, i);
> > + if (ret)
>
> [1] ... here.
>
> Otherwise, it is likely that, thanks to a static checker, an
> additionnal
> of_node_put() will be added on early exit of the loop.
>
> CJ
>
> > + return ret;
> > + i++;
> > + }
> > +
> > + return 0;
> > +}
>
> ...
>
Best regards,
André