Merge tag 'pwm/for-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "This set contains mostly fixes to existing drivers as well as cleanup
  of code that's not been in active use for a while"

* tag 'pwm/for-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (27 commits)
  acpi: lpss: call pwm_add_table() for BSW PWM device
  pwm: Try to load modules during pwm_get()
  pwm: Don't hold pwm_lookup_lock longer than necessary
  pwm: Make the PWM_POLARITY flag in DTB optional
  pwm: Print error messages with pr_err() instead of pr_debug()
  pwm: imx: Add polarity inversion support to i.MX's PWMv2
  pwm: imx: doc: Update imx-pwm.txt documentation entry
  pwm: imx: Remove redundant i.MX PWMv2 code
  pwm: imx: Provide atomic PWM support for i.MX PWMv2
  pwm: imx: Move PWMv2 wait for fifo slot code to a separate function
  pwm: imx: Move PWMv2 software reset code to a separate function
  pwm: imx: Rewrite v1 code to facilitate switch to atomic PWM
  pwm: imx: Add separate set of PWM ops for v1 and v2
  pwm: imx: Remove ipg clock and enable per clock when required
  pwm: lpss: Add Intel Gemini Lake PCI ID
  pwm: lpss: Do not export board infos for different PWM types
  pwm: lpss: Avoid reconfiguring while UPDATE bit is still enabled
  pwm: lpss: Switch to new atomic API
  pwm: lpss: Allow duty cycle to be 0
  pwm: lpss: Avoid potential overflow of base_unit
  ...

1 files changed, 36 insertions, 34 deletions

diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 172ef8245811..a0860b30bd93 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -137,9 +137,14 @@ of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args)
 {
 	struct pwm_device *pwm;
 
+	/* check, whether the driver supports a third cell for flags */
 	if (pc->of_pwm_n_cells < 3)
 		return ERR_PTR(-EINVAL);
 
+	/* flags in the third cell are optional */
+	if (args->args_count < 2)
+		return ERR_PTR(-EINVAL);
+
 	if (args->args[0] >= pc->npwm)
 		return ERR_PTR(-EINVAL);
 
@@ -148,11 +153,10 @@ of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args)
 		return pwm;
 
 	pwm->args.period = args->args[1];
+	pwm->args.polarity = PWM_POLARITY_NORMAL;
 
-	if (args->args[2] & PWM_POLARITY_INVERTED)
+	if (args->args_count > 2 && args->args[2] & PWM_POLARITY_INVERTED)
 		pwm->args.polarity = PWM_POLARITY_INVERSED;
-	else
-		pwm->args.polarity = PWM_POLARITY_NORMAL;
 
 	return pwm;
 }
@@ -163,9 +167,14 @@ of_pwm_simple_xlate(struct pwm_chip *pc, const struct of_phandle_args *args)
 {
 	struct pwm_device *pwm;
 
+	/* sanity check driver support */
 	if (pc->of_pwm_n_cells < 2)
 		return ERR_PTR(-EINVAL);
 
+	/* all cells are required */
+	if (args->args_count != pc->of_pwm_n_cells)
+		return ERR_PTR(-EINVAL);
+
 	if (args->args[0] >= pc->npwm)
 		return ERR_PTR(-EINVAL);
 
@@ -663,24 +672,17 @@ struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id)
 	err = of_parse_phandle_with_args(np, "pwms", "#pwm-cells", index,
 					 &args);
 	if (err) {
-		pr_debug("%s(): can't parse \"pwms\" property\n", __func__);
+		pr_err("%s(): can't parse \"pwms\" property\n", __func__);
 		return ERR_PTR(err);
 	}
 
 	pc = of_node_to_pwmchip(args.np);
 	if (IS_ERR(pc)) {
-		pr_debug("%s(): PWM chip not found\n", __func__);
+		pr_err("%s(): PWM chip not found\n", __func__);
 		pwm = ERR_CAST(pc);
 		goto put;
 	}
 
-	if (args.args_count != pc->of_pwm_n_cells) {
-		pr_debug("%s: wrong #pwm-cells for %s\n", np->full_name,
-			 args.np->full_name);
-		pwm = ERR_PTR(-EINVAL);
-		goto put;
-	}
-
 	pwm = pc->of_xlate(pc, &args);
 	if (IS_ERR(pwm))
 		goto put;
@@ -757,12 +759,13 @@ void pwm_remove_table(struct pwm_lookup *table, size_t num)
  */
 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)
@@ -817,24 +820,35 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id)
 		}
 	}
 
-	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);
@@ -960,18 +974,6 @@ void devm_pwm_put(struct device *dev, struct pwm_device *pwm)
 }
 EXPORT_SYMBOL_GPL(devm_pwm_put);
 
-/**
-  * pwm_can_sleep() - report whether PWM access will sleep
-  * @pwm: PWM device
-  *
-  * Returns: True if accessing the PWM can sleep, false otherwise.
-  */
-bool pwm_can_sleep(struct pwm_device *pwm)
-{
-	return true;
-}
-EXPORT_SYMBOL_GPL(pwm_can_sleep);
-
 #ifdef CONFIG_DEBUG_FS
 static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s)
 {