[PATCH v6 3/7] pwm: tegra: Avoid hard-coded max clock frequency

From: Yi-Wei Wang <[email protected]>

The clock driving the Tegra PWM IP can be sourced from different parent
clocks. Hence, let dev_pm_opp_set_rate() set the max clock rate based
upon the current parent clock that can be specified via device-tree.

After this, the Tegra194 SoC data becomes redundant, so get rid of it.

Signed-off-by: Yi-Wei Wang <[email protected]>
Reviewed-by: Thierry Reding <[email protected]>
Co-developed-by: Mikko Perttunen <[email protected]>
Signed-off-by: Mikko Perttunen <[email protected]>
---
 drivers/pwm/pwm-tegra.c | 21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c
index f8c5495a56a6..3eef299c51f8 100644
--- a/drivers/pwm/pwm-tegra.c
+++ b/drivers/pwm/pwm-tegra.c
@@ -59,9 +59,6 @@
 
 struct tegra_pwm_soc {
 	unsigned int num_channels;
-
-	/* Maximum IP frequency for given SoCs */
-	unsigned long max_frequency;
 };
 
 struct tegra_pwm_chip {
@@ -303,7 +300,7 @@ static int tegra_pwm_probe(struct platform_device *pdev)
 		return ret;
 
 	/* Set maximum frequency of the IP */
-	ret = dev_pm_opp_set_rate(&pdev->dev, pc->soc->max_frequency);
+	ret = dev_pm_opp_set_rate(&pdev->dev, ULONG_MAX);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "Failed to set max frequency: %d\n", ret);
 		goto put_pm;
@@ -315,10 +312,15 @@ static int tegra_pwm_probe(struct platform_device *pdev)
 	 * so that PWM period can be calculated more accurately.
 	 */
 	pc->clk_rate = clk_get_rate(pc->clk);
+	if (pc->clk_rate < (1 << TEGRA_PWM_DUTY_WIDTH)) {
+		dev_err(&pdev->dev, "clock maximum frequency out of range\n");
+		ret = -ERANGE;
+		goto put_pm;
+	}
 
 	/* Set minimum limit of PWM period for the IP */
 	pc->min_period_ns =
-	    (NSEC_PER_SEC / (pc->soc->max_frequency >> TEGRA_PWM_DUTY_WIDTH)) + 1;
+	    (NSEC_PER_SEC / (pc->clk_rate >> TEGRA_PWM_DUTY_WIDTH)) + 1;
 
 	pc->rst = devm_reset_control_get_exclusive(&pdev->dev, "pwm");
 	if (IS_ERR(pc->rst)) {
@@ -397,23 +399,16 @@ static int __maybe_unused tegra_pwm_runtime_resume(struct device *dev)
 
 static const struct tegra_pwm_soc tegra20_pwm_soc = {
 	.num_channels = 4,
-	.max_frequency = 48000000UL,
 };
 
 static const struct tegra_pwm_soc tegra186_pwm_soc = {
 	.num_channels = 1,
-	.max_frequency = 102000000UL,
-};
-
-static const struct tegra_pwm_soc tegra194_pwm_soc = {
-	.num_channels = 1,
-	.max_frequency = 408000000UL,
 };
 
 static const struct of_device_id tegra_pwm_of_match[] = {
 	{ .compatible = "nvidia,tegra20-pwm", .data = &tegra20_pwm_soc },
 	{ .compatible = "nvidia,tegra186-pwm", .data = &tegra186_pwm_soc },
-	{ .compatible = "nvidia,tegra194-pwm", .data = &tegra194_pwm_soc },
+	{ .compatible = "nvidia,tegra194-pwm", .data = &tegra186_pwm_soc },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, tegra_pwm_of_match);

-- 
2.53.0