From: Jonas Schwöbel <jonasschwoebel@yahoo.de>
Date: Tue, 11 Mar 2025 22:01:20 +0000 (+0100)
Subject: pwm: tegra: add probe function
X-Git-Tag: v2026.07-rc1~63^2~17^2~17
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=5dcdbcf7833ae762866c43cbd872ba910576d228;p=thirdparty%2Fu-boot.git

pwm: tegra: add probe function

When PWM config was updated the clock was restarted which caused loss of
previous configuration of other channels. Further this fixes a bug/hang
that can happen when set_enable was called before set_config.

Signed-off-by: Jonas Schwöbel <jonasschwoebel@yahoo.de>
Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
---

diff --git a/drivers/pwm/tegra_pwm.c b/drivers/pwm/tegra_pwm.c
index e3f1417f2ad..919728b821f 100644
--- a/drivers/pwm/tegra_pwm.c
+++ b/drivers/pwm/tegra_pwm.c
@@ -4,6 +4,7 @@
  */
 
 #include <dm.h>
+#include <clk.h>
 #include <log.h>
 #include <pwm.h>
 #include <asm/io.h>
@@ -19,7 +20,6 @@ static int tegra_pwm_set_config(struct udevice *dev, uint channel,
 {
 	struct tegra_pwm_priv *priv = dev_get_priv(dev);
 	struct pwm_ctlr *regs = priv->regs;
-	const u32 pwm_max_freq = dev_get_driver_data(dev);
 	uint pulse_width;
 	u32 reg;
 
@@ -27,8 +27,6 @@ static int tegra_pwm_set_config(struct udevice *dev, uint channel,
 		return -EINVAL;
 	debug("%s: Configure '%s' channel %u\n", __func__, dev->name, channel);
 
-	clock_start_periph_pll(PERIPH_ID_PWM, CLOCK_ID_PERIPH, pwm_max_freq);
-
 	pulse_width = duty_ns * 255 / period_ns;
 
 	reg = pulse_width << PWM_WIDTH_SHIFT;
@@ -63,6 +61,22 @@ static int tegra_pwm_of_to_plat(struct udevice *dev)
 	return 0;
 }
 
+static int tegra_pwm_probe(struct udevice *dev)
+{
+	const u32 pwm_max_freq = dev_get_driver_data(dev);
+	struct clk *clk;
+
+	clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(clk)) {
+		debug("%s: Could not get PWM clock: %ld\n", __func__, PTR_ERR(clk));
+		return PTR_ERR(clk);
+	}
+
+	clock_start_periph_pll(clk->id, CLOCK_ID_PERIPH, pwm_max_freq);
+
+	return 0;
+}
+
 static const struct pwm_ops tegra_pwm_ops = {
 	.set_config	= tegra_pwm_set_config,
 	.set_enable	= tegra_pwm_set_enable,
@@ -80,5 +94,6 @@ U_BOOT_DRIVER(tegra_pwm) = {
 	.of_match = tegra_pwm_ids,
 	.ops	= &tegra_pwm_ops,
 	.of_to_plat	= tegra_pwm_of_to_plat,
+	.probe		= tegra_pwm_probe,
 	.priv_auto	= sizeof(struct tegra_pwm_priv),
 };