Merge tag 'pwm/for-6.16-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux

Pull pwm fixes from Uwe Kleine-König:
 "axi-pwmgen: Fix handling of external clock

  The pwm-axi-pwmgen device is backed by an FPGA and can be synthesized
  in different ways. Relevant here is that it can use one or two
  external clock signals. These fix clock handling for the two clocks
  case"

* tag 'pwm/for-6.16-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux:
  pwm: axi-pwmgen: fix missing separate external clock
  dt-bindings: pwm: adi,axi-pwmgen: Fix clocks

1 files changed, 20 insertions, 3 deletions

diff --git a/drivers/pwm/pwm-axi-pwmgen.c b/drivers/pwm/pwm-axi-pwmgen.c
index 4337c8f5acf0..60dcd3542373 100644
--- a/drivers/pwm/pwm-axi-pwmgen.c
+++ b/drivers/pwm/pwm-axi-pwmgen.c
@@ -257,7 +257,7 @@ static int axi_pwmgen_probe(struct platform_device *pdev)
 	struct regmap *regmap;
 	struct pwm_chip *chip;
 	struct axi_pwmgen_ddata *ddata;
-	struct clk *clk;
+	struct clk *axi_clk, *clk;
 	void __iomem *io_base;
 	int ret;
 
@@ -280,9 +280,26 @@ static int axi_pwmgen_probe(struct platform_device *pdev)
 	ddata = pwmchip_get_drvdata(chip);
 	ddata->regmap = regmap;
 
-	clk = devm_clk_get_enabled(dev, NULL);
+	/*
+	 * Using NULL here instead of "axi" for backwards compatibility. There
+	 * are some dtbs that don't give clock-names and have the "ext" clock
+	 * as the one and only clock (due to mistake in the original bindings).
+	 */
+	axi_clk = devm_clk_get_enabled(dev, NULL);
+	if (IS_ERR(axi_clk))
+		return dev_err_probe(dev, PTR_ERR(axi_clk), "failed to get axi clock\n");
+
+	clk = devm_clk_get_optional_enabled(dev, "ext");
 	if (IS_ERR(clk))
-		return dev_err_probe(dev, PTR_ERR(clk), "failed to get clock\n");
+		return dev_err_probe(dev, PTR_ERR(clk), "failed to get ext clock\n");
+
+	/*
+	 * If there is no "ext" clock, it means the HDL was compiled with
+	 * ASYNC_CLK_EN=0. In this case, the AXI clock is also used for the
+	 * PWM output clock.
+	 */
+	if (!clk)
+		clk = axi_clk;
 
 	ret = devm_clk_rate_exclusive_get(dev, clk);
 	if (ret)