Re: [PATCH v5 2/2] leds: add ktd202x driver
Am Sonntag, dem 01.10.2023 um 22:46 +0200 schrieb Christophe JAILLET: > Le 01/10/2023 à 18:56, André Apitzsch a écrit : > > 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 > > > > > > > > > > ... > > > > > > > +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? > > How can the caller do this? > > The goal of this of_node_put() is to release a reference taken by the > for_each_available_child_of_node() loop, in case of early exit. > > The caller can't know if np needs to be released or not. An error > code > is returned either if an error occurs within the for_each loop, or if > devm_led_classdev_multicolor_register_ext() fails. > > More over, in your case the caller is ktd202x_add_led(). > From there either ktd202x_setup_led_rgb() or > ktd202x_setup_led_single() > is called. > > ktd202x_setup_led_single() does not take any reference to np. > But if it fails, of_node_put() would still be called. > > Hello Christophe, It seems I misunderstood when of_node_put() is used. Thanks for the explanation. While checking the usage of of_node_put(), I noticed that dev_err() (and of_node_put()) should take "child" and not "np", here. André > > > > > > > + return -EINVAL; > > > > + } > > > > + > > > > + ret = of_property_read_u32(child, "color", > > > > _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 = >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, > > > > >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 = >cdev; > > > > + cdev->brightness_set_blocking = > > > > ktd202x_brightness_single_set; > > > > + cdev->blink_set = ktd202x_blink_single_set; > > > > + > > > > + return devm_led_classdev_register_ext(chip->dev, > > > > > cdev, init_data); > > > > +} > > > > + > > > > +static int ktd202x_add_led(struct ktd202x *chip, struct > > > > device_node *np, unsigned
Re: [PATCH v5 2/2] leds: add ktd202x driver
Le 01/10/2023 à 18:56, André Apitzsch a écrit : 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 ... +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? How can the caller do this? The goal of this of_node_put() is to release a reference taken by the for_each_available_child_of_node() loop, in case of early exit. The caller can't know if np needs to be released or not. An error code is returned either if an error occurs within the for_each loop, or if devm_led_classdev_multicolor_register_ext() fails. More over, in your case the caller is ktd202x_add_led(). From there either ktd202x_setup_led_rgb() or ktd202x_setup_led_single() is called. ktd202x_setup_led_single() does not take any reference to np. But if it fails, of_node_put() would still be called. + return -EINVAL; + } + + ret = of_property_read_u32(child, "color", _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 = >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, >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 = >cdev; + cdev->brightness_set_blocking = ktd202x_brightness_single_set; + cdev->blink_set = ktd202x_blink_single_set; + + return devm_led_classdev_register_ext(chip->dev, cdev, init_data); +} + +static int ktd202x_add_led(struct ktd202x *chip, struct device_node *np, unsigned int index) +{ + struct ktd202x_led *led = >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", ); + 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 = >mcdev.led_cdev; + ret = ktd202x_setup_led_rgb(chip, np, led, _data); + } else { + cdev = >cdev; + ret = ktd202x_setup_led_single(chip, np, led, _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]. Why [2]? It does not seem needed here.
Re: [PATCH v5 2/2] leds: add ktd202x driver
Hello André, On Sun, Oct 01, 2023 at 06:56:20PM +0200, André Apitzsch wrote: > Am Sonntag, dem 01.10.2023 um 17:15 +0200 schrieb Christophe JAILLET: > > Le 01/10/2023 à 15:52, André Apitzsch a écrit : > > > + 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). In my book a variable with a narrow scope is better. I didn't check, but if you can restrict both variables to the for loop, that's nicer. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König| Industrial Linux Solutions | https://www.pengutronix.de/ | signature.asc Description: PGP signature
Re: [PATCH v5 2/2] leds: add ktd202x driver
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 > > > > ... > > > +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", > > _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 = >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, > > >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 = >cdev; > > + cdev->brightness_set_blocking = > > ktd202x_brightness_single_set; > > + cdev->blink_set = ktd202x_blink_single_set; > > + > > + return devm_led_classdev_register_ext(chip->dev, > > >cdev, init_data); > > +} > > + > > +static int ktd202x_add_led(struct ktd202x *chip, struct > > device_node *np, unsigned int index) > > +{ > > + struct ktd202x_led *led = >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", ); > > + 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 = >mcdev.led_cdev; > > + ret = ktd202x_setup_led_rgb(chip, np, led, > > _data); > > + } else { > > + cdev = >cdev; > > + ret = ktd202x_setup_led_single(chip, np, led, > > _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) > > +{ > > +
Re: [PATCH v5 2/2] leds: add ktd202x driver
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 ... +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? + + 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);? + return -EINVAL; + } + + ret = of_property_read_u32(child, "color", _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 = >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, >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 = >cdev; + cdev->brightness_set_blocking = ktd202x_brightness_single_set; + cdev->blink_set = ktd202x_blink_single_set; + + return devm_led_classdev_register_ext(chip->dev, >cdev, init_data); +} + +static int ktd202x_add_led(struct ktd202x *chip, struct device_node *np, unsigned int index) +{ + struct ktd202x_led *led = >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", ); + 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 = >mcdev.led_cdev; + ret = ktd202x_setup_led_rgb(chip, np, led, _data); + } else { + cdev = >cdev; + ret = ktd202x_setup_led_single(chip, np, led, _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] + 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) + 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 +