Re: [PATCH 2/2] pwm: airoha: Add support for EN7581 SoC

On 10/08/2024 06:48, Lorenzo Bianconi wrote:

From: Benjamin Larsson <redacted>

Introduce driver for PWM module available on EN7581 SoC.

Signed-off-by: Benjamin Larsson <redacted>
Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---

...

+
+static void airoha_pwm_config_flash_map(struct airoha_pwm *pc,
+					unsigned int hwpwm, int index)
+{
+	u32 addr, mask, val;
+
+	if (hwpwm < PWM_NUM_GPIO) {
+		addr = REG_GPIO_FLASH_MAP(hwpwm / 8);
+	} else {
+		addr = REG_SIPO_FLASH_MAP(hwpwm / 8);
+		hwpwm -= PWM_NUM_GPIO;
+	}
+
+	if (index < 0) {
+		/* Change of waveform takes effect immediately but

This and other comments should be not netdev-style but general Linux style.

+		 * disabling has some delay so to prevent glitching
+		 * only the enable bit is touched when disabling
+		 */
+		airoha_pwm_flash_clear(pc, addr, GPIO_FLASH_EN(hwpwm % 8));
+		return;

...

+
+static const struct of_device_id airoha_pwm_of_match[] = {
+	{ .compatible = "airoha,en7581-pwm" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, airoha_pwm_of_match);
+
+static struct platform_driver airoha_pwm_driver = {
+	.driver = {
+		.name = "airoha-pwm",
+		.of_match_table = airoha_pwm_of_match,
+	},
+	.probe = airoha_pwm_probe,
+};
+module_platform_driver(airoha_pwm_driver);
+
+MODULE_ALIAS("platform:airoha-pwm");

You should not need MODULE_ALIAS() in normal cases. If you need it,
usually it means your device ID table is wrong (e.g. misses either
entries or MODULE_DEVICE_TABLE()). MODULE_ALIAS() is not a substitute
for incomplete ID table.

Especially that it does not match compatible, so you cannot use excuse
module autoloading does not work for given OF node...


Best regards,
Krzysztof