*/
struct pwm_device *pwm_get(struct device *dev, const char *con_id)
{
- struct pwm_device *pwm = ERR_PTR(-EPROBE_DEFER);
const char *dev_id = dev ? dev_name(dev) : NULL;
- struct pwm_chip *chip = NULL;
+ struct pwm_device *pwm;
+ struct pwm_chip *chip;
unsigned int best = 0;
struct pwm_lookup *p, *chosen = NULL;
unsigned int match;
+ int err;
/* look up via DT first */
if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
}
}
- if (!chosen) {
- pwm = ERR_PTR(-ENODEV);
- goto out;
- }
+ mutex_unlock(&pwm_lookup_lock);
+
+ if (!chosen)
+ return ERR_PTR(-ENODEV);
chip = pwmchip_find_by_name(chosen->provider);
+
+ /*
+ * If the lookup entry specifies a module, load the module and retry
+ * the PWM chip lookup. This can be used to work around driver load
+ * ordering issues if driver's can't be made to properly support the
+ * deferred probe mechanism.
+ */
+ if (!chip && chosen->module) {
+ err = request_module(chosen->module);
+ if (err == 0)
+ chip = pwmchip_find_by_name(chosen->provider);
+ }
+
if (!chip)
- goto out;
+ return ERR_PTR(-EPROBE_DEFER);
pwm = pwm_request_from_chip(chip, chosen->index, con_id ?: dev_id);
if (IS_ERR(pwm))
- goto out;
+ return pwm;
pwm->args.period = chosen->period;
pwm->args.polarity = chosen->polarity;
-out:
- mutex_unlock(&pwm_lookup_lock);
return pwm;
}
EXPORT_SYMBOL_GPL(pwm_get);