From 33f339b70f020273ea40fb3c5d7b65697446bd6c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marek=20Beh=C3=BAn?= Date: Mon, 16 Oct 2023 15:28:06 +0200 Subject: [PATCH 08/17] leds: turris-omnia: Fix brightness setting and trigger activating MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit I have improperly refactored commits 4d5ed2621c24 ("leds: turris-omnia: Make set_brightness() more efficient") and aaf38273cf76 ("leds: turris-omnia: Support HW controlled mode via private trigger") after Lee requested a change in API semantics of the new functions I introduced in commit 28350bc0ac77 ("leds: turris-omnia: Do not use SMBUS calls"). Before the change, the function omnia_cmd_write_u8() returned 0 on success, and afterwards it returned a positive value (number of bytes written). The latter version was applied, but the following commits did not properly account for this change. This results in non-functional LED's .brightness_set_blocking() and trigger's .activate() methods. The main reasoning behind the semantics change was that read/write methods should return the number of read/written bytes on success. It was pointed to me [1] that this is not always true (for example the regmap API does not do so), and since the driver never uses this number of read/written bytes information, I decided to fix this issue by changing the functions to the original semantics (return 0 on success). [1] https://lore.kernel.org/linux-gpio/ZQnn+Gi0xVlsGCYA@smile.fi.intel.com/ Fixes: 28350bc0ac77 ("leds: turris-omnia: Do not use SMBUS calls") Signed-off-by: Marek Behún --- drivers/leds/leds-turris-omnia.c | 37 +++++++++++++++++--------------- 1 file changed, 20 insertions(+), 17 deletions(-) --- a/drivers/leds/leds-turris-omnia.c +++ b/drivers/leds/leds-turris-omnia.c @@ -60,8 +60,11 @@ struct omnia_leds { static int omnia_cmd_write_u8(const struct i2c_client *client, u8 cmd, u8 val) { u8 buf[2] = { cmd, val }; + int ret; + + ret = i2c_master_send(client, buf, sizeof(buf)); - return i2c_master_send(client, buf, sizeof(buf)); + return ret < 0 ? ret : 0; } static int omnia_cmd_read_raw(struct i2c_adapter *adapter, u8 addr, u8 cmd, @@ -81,7 +84,7 @@ static int omnia_cmd_read_raw(struct i2c ret = i2c_transfer(adapter, msgs, ARRAY_SIZE(msgs)); if (likely(ret == ARRAY_SIZE(msgs))) - return len; + return 0; else if (ret < 0) return ret; else @@ -91,11 +94,11 @@ static int omnia_cmd_read_raw(struct i2c static int omnia_cmd_read_u8(const struct i2c_client *client, u8 cmd) { u8 reply; - int ret; + int err; - ret = omnia_cmd_read_raw(client->adapter, client->addr, cmd, &reply, 1); - if (ret < 0) - return ret; + err = omnia_cmd_read_raw(client->adapter, client->addr, cmd, &reply, 1); + if (err) + return err; return reply; } @@ -236,7 +239,7 @@ static void omnia_hwtrig_deactivate(stru mutex_unlock(&leds->lock); - if (err < 0) + if (err) dev_err(cdev->dev, "Cannot put LED to software mode: %i\n", err); } @@ -302,7 +305,7 @@ static int omnia_led_register(struct i2c ret = omnia_cmd_write_u8(client, CMD_LED_MODE, CMD_LED_MODE_LED(led->reg) | CMD_LED_MODE_USER); - if (ret < 0) { + if (ret) { dev_err(dev, "Cannot set LED %pOF to software mode: %i\n", np, ret); return ret; @@ -311,7 +314,7 @@ static int omnia_led_register(struct i2c /* disable the LED */ ret = omnia_cmd_write_u8(client, CMD_LED_STATE, CMD_LED_STATE_LED(led->reg)); - if (ret < 0) { + if (ret) { dev_err(dev, "Cannot set LED %pOF brightness: %i\n", np, ret); return ret; } @@ -364,7 +367,7 @@ static ssize_t brightness_store(struct d { struct i2c_client *client = to_i2c_client(dev); unsigned long brightness; - int ret; + int err; if (kstrtoul(buf, 10, &brightness)) return -EINVAL; @@ -372,9 +375,9 @@ static ssize_t brightness_store(struct d if (brightness > 100) return -EINVAL; - ret = omnia_cmd_write_u8(client, CMD_LED_SET_BRIGHTNESS, brightness); + err = omnia_cmd_write_u8(client, CMD_LED_SET_BRIGHTNESS, brightness); - return ret < 0 ? ret : count; + return err ?: count; } static DEVICE_ATTR_RW(brightness); @@ -403,7 +406,7 @@ static ssize_t gamma_correction_store(st struct i2c_client *client = to_i2c_client(dev); struct omnia_leds *leds = i2c_get_clientdata(client); bool val; - int ret; + int err; if (!leds->has_gamma_correction) return -EOPNOTSUPP; @@ -411,9 +414,9 @@ static ssize_t gamma_correction_store(st if (kstrtobool(buf, &val) < 0) return -EINVAL; - ret = omnia_cmd_write_u8(client, CMD_SET_GAMMA_CORRECTION, val); + err = omnia_cmd_write_u8(client, CMD_SET_GAMMA_CORRECTION, val); - return ret < 0 ? ret : count; + return err ?: count; } static DEVICE_ATTR_RW(gamma_correction); @@ -431,7 +434,7 @@ static int omnia_mcu_get_features(const err = omnia_cmd_read_raw(client->adapter, OMNIA_MCU_I2C_ADDR, CMD_GET_STATUS_WORD, &reply, sizeof(reply)); - if (err < 0) + if (err) return err; /* Check whether MCU firmware supports the CMD_GET_FEAUTRES command */ @@ -440,7 +443,7 @@ static int omnia_mcu_get_features(const err = omnia_cmd_read_raw(client->adapter, OMNIA_MCU_I2C_ADDR, CMD_GET_FEATURES, &reply, sizeof(reply)); - if (err < 0) + if (err) return err; return le16_to_cpu(reply);