diff options
author | Eddie James <eajames@linux.ibm.com> | 2022-04-12 19:42:10 +0300 |
---|---|---|
committer | Joel Stanley <joel@jms.id.au> | 2022-04-15 07:34:59 +0300 |
commit | 6bb80845fd6b60c3905c65a2411fa0e8d0ba7872 (patch) | |
tree | 1154efd681235c4b907f42fad259699989473b92 | |
parent | d321b49f93b3c898a557905d793861e6cd609824 (diff) | |
download | linux-6bb80845fd6b60c3905c65a2411fa0e8d0ba7872.tar.xz |
leds: pca955x: Optimize probe led selection
Previously, the probe function might do up to 32 reads and writes
to the same 4 registers to program the led selection. Reduce this to
a maximum of 8 operations by accumulating the changes to the led
selection and comparing with the previous value to write the
selection if different.
OpenBMC-Staging-Count: 1
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220412164211.28824-4-eajames@linux.ibm.com
Signed-off-by: Joel Stanley <joel@jms.id.au>
-rw-r--r-- | drivers/leds/leds-pca955x.c | 40 |
1 files changed, 29 insertions, 11 deletions
diff --git a/drivers/leds/leds-pca955x.c b/drivers/leds/leds-pca955x.c index cb1895b79eab..61f3cb84a945 100644 --- a/drivers/leds/leds-pca955x.c +++ b/drivers/leds/leds-pca955x.c @@ -483,7 +483,9 @@ static int pca955x_probe(struct i2c_client *client) struct led_classdev *led; struct led_init_data init_data; struct i2c_adapter *adapter; - int i, err; + int i, bit, err, nls, reg; + u8 ls1[4]; + u8 ls2[4]; struct pca955x_platform_data *pdata; bool set_default_label = false; bool keep_pwm = false; @@ -554,6 +556,15 @@ static int pca955x_probe(struct i2c_client *client) init_data.devname_mandatory = false; init_data.devicename = "pca955x"; + nls = pca955x_num_led_regs(chip->bits); + for (i = 0; i < nls; ++i) { + err = pca955x_read_ls(pca955x, i, &ls1[i]); + if (err) + return err; + + ls2[i] = ls1[i]; + } + for (i = 0; i < chip->bits; i++) { pca955x_led = &pca955x->leds[i]; pca955x_led->led_num = i; @@ -565,21 +576,20 @@ static int pca955x_probe(struct i2c_client *client) case PCA955X_TYPE_GPIO: break; case PCA955X_TYPE_LED: + bit = i % 4; + reg = i / 4; led = &pca955x_led->led_cdev; led->brightness_set_blocking = pca955x_led_set; led->brightness_get = pca955x_led_get; if (pdata->leds[i].default_state == - LEDS_GPIO_DEFSTATE_OFF) { - err = pca955x_led_set(led, LED_OFF); - if (err) - return err; - } else if (pdata->leds[i].default_state == - LEDS_GPIO_DEFSTATE_ON) { - err = pca955x_led_set(led, LED_FULL); - if (err) - return err; - } + LEDS_GPIO_DEFSTATE_OFF) + ls2[reg] = pca955x_ledsel(ls2[reg], bit, + PCA955X_LS_LED_OFF); + else if (pdata->leds[i].default_state == + LEDS_GPIO_DEFSTATE_ON) + ls2[reg] = pca955x_ledsel(ls2[reg], bit, + PCA955X_LS_LED_ON); init_data.fwnode = pdata->leds[i].fwnode; @@ -624,6 +634,14 @@ static int pca955x_probe(struct i2c_client *client) } } + for (i = 0; i < nls; ++i) { + if (ls1[i] != ls2[i]) { + err = pca955x_write_ls(pca955x, i, ls2[i]); + if (err) + return err; + } + } + /* PWM0 is used for half brightness or 50% duty cycle */ err = pca955x_write_pwm(pca955x, 0, 255 - LED_HALF); if (err) |