[PW_SID:954714] riscv: pwm: sophgo: add pwm support for SG2044

Documentation/devicetree/bindings/pwm/sophgo,sg2042-pwm.yaml

@@ -17,7 +17,9 @@ allOf:
 
 properties:
   compatible:
-    const: sophgo,sg2042-pwm
+    enum:
+      - sophgo,sg2042-pwm
+      - sophgo,sg2044-pwm
 
   reg:
     maxItems: 1

drivers/pwm/pwm-sophgo-sg2042.c

@@ -13,6 +13,9 @@
  *   the running period.
  * - When PERIOD and HLPERIOD is set to 0, the PWM wave output will
  *   be stopped and the output is pulled to high.
+ * - SG2044 support polarity while SG2042 does not. When PWMSTART is
+ *   false, POLARITY being NORMAL will make output being low,
+ *   POLARITY being INVERSED will make output being high.
  * See the datasheet [1] for more details.
  * [1]:https://github.com/sophgo/sophgo-doc/tree/main/SG2042/TRM
  */
@@ -26,18 +29,10 @@
 #include <linux/pwm.h>
 #include <linux/reset.h>
 
-/*
- * Offset RegisterName
- * 0x0000 HLPERIOD0
- * 0x0004 PERIOD0
- * 0x0008 HLPERIOD1
- * 0x000C PERIOD1
- * 0x0010 HLPERIOD2
- * 0x0014 PERIOD2
- * 0x0018 HLPERIOD3
- * 0x001C PERIOD3
- * Four groups and every group is composed of HLPERIOD & PERIOD
- */
+#define SG2044_REG_POLARITY		0x40
+#define SG2044_REG_PWMSTART		0x44
+#define SG2044_REG_PWM_OE		0xD0
+
 #define SG2042_PWM_HLPERIOD(chan) ((chan) * 8 + 0)
 #define SG2042_PWM_PERIOD(chan) ((chan) * 8 + 4)
 
@@ -53,6 +48,10 @@ struct sg2042_pwm_ddata {
 	unsigned long clk_rate_hz;
 };
 
+struct sg2042_chip_data {
+	const struct pwm_ops ops;
+};
+
 /*
  * period_ticks: PERIOD
  * hlperiod_ticks: HLPERIOD
@@ -66,32 +65,40 @@ static void pwm_sg2042_config(struct sg2042_pwm_ddata *ddata, unsigned int chan,
 	writel(hlperiod_ticks, base + SG2042_PWM_HLPERIOD(chan));
 }
 
-static int pwm_sg2042_apply(struct pwm_chip *chip, struct pwm_device *pwm,
-			    const struct pwm_state *state)
+static void pwm_set_dutycycle(struct pwm_chip *chip, struct pwm_device *pwm,
+			      const struct pwm_state *state)
 {
 	struct sg2042_pwm_ddata *ddata = pwmchip_get_drvdata(chip);
 	u32 hlperiod_ticks;
 	u32 period_ticks;
 
-	if (state->polarity == PWM_POLARITY_INVERSED)
-		return -EINVAL;
-
-	if (!state->enabled) {
-		pwm_sg2042_config(ddata, pwm->hwpwm, 0, 0);
-		return 0;
-	}
-
 	/*
 	 * Duration of High level (duty_cycle) = HLPERIOD x Period_of_input_clk
 	 * Duration of One Cycle (period) = PERIOD x Period_of_input_clk
 	 */
 	period_ticks = min(mul_u64_u64_div_u64(ddata->clk_rate_hz, state->period, NSEC_PER_SEC), U32_MAX);
 	hlperiod_ticks = min(mul_u64_u64_div_u64(ddata->clk_rate_hz, state->duty_cycle, NSEC_PER_SEC), U32_MAX);
 
-	dev_dbg(pwmchip_parent(chip), "chan[%u]: PERIOD=%u, HLPERIOD=%u\n",
-		pwm->hwpwm, period_ticks, hlperiod_ticks);
+	dev_dbg(pwmchip_parent(chip), "chan[%u]: ENABLE=%u, PERIOD=%u, HLPERIOD=%u, POLARITY=%u\n",
+		pwm->hwpwm, state->enabled, period_ticks, hlperiod_ticks, state->polarity);
 
 	pwm_sg2042_config(ddata, pwm->hwpwm, period_ticks, hlperiod_ticks);
+}
+
+static int pwm_sg2042_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+			    const struct pwm_state *state)
+{
+	struct sg2042_pwm_ddata *ddata = pwmchip_get_drvdata(chip);
+
+	if (state->polarity == PWM_POLARITY_INVERSED)
+		return -EINVAL;
+
+	if (!state->enabled) {
+		pwm_sg2042_config(ddata, pwm->hwpwm, 0, 0);
+		return 0;
+	}
+
+	pwm_set_dutycycle(chip, pwm, state);
 
 	return 0;
 }
@@ -123,26 +130,111 @@ static int pwm_sg2042_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
 	return 0;
 }
 
-static const struct pwm_ops pwm_sg2042_ops = {
-	.apply = pwm_sg2042_apply,
-	.get_state = pwm_sg2042_get_state,
+static void pwm_sg2044_set_start(struct sg2042_pwm_ddata *ddata, struct pwm_device *pwm,
+				 bool enabled)
+{
+	u32 pwm_value;
+
+	pwm_value = readl(ddata->base + SG2044_REG_PWMSTART);
+
+	if (enabled)
+		pwm_value |= BIT(pwm->hwpwm);
+	else
+		pwm_value &= ~BIT(pwm->hwpwm);
+
+	writel(pwm_value, ddata->base + SG2044_REG_PWMSTART);
+}
+
+static void pwm_sg2044_set_outputdir(struct sg2042_pwm_ddata *ddata, struct pwm_device *pwm,
+				     bool enabled)
+{
+	u32 pwm_value;
+
+	pwm_value = readl(ddata->base + SG2044_REG_PWM_OE);
+
+	if (enabled)
+		pwm_value |= BIT(pwm->hwpwm);
+	else
+		pwm_value &= ~BIT(pwm->hwpwm);
+
+	writel(pwm_value, ddata->base + SG2044_REG_PWM_OE);
+}
+
+static void pwm_sg2044_set_polarity(struct sg2042_pwm_ddata *ddata, struct pwm_device *pwm,
+				    const struct pwm_state *state)
+{
+	u32 pwm_value;
+
+	pwm_value = readl(ddata->base + SG2044_REG_POLARITY);
+
+	if (state->polarity == PWM_POLARITY_NORMAL)
+		pwm_value &= ~BIT(pwm->hwpwm);
+	else
+		pwm_value |= BIT(pwm->hwpwm);
+
+	writel(pwm_value, ddata->base + SG2044_REG_POLARITY);
+}
+
+static int pwm_sg2044_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+			    const struct pwm_state *state)
+{
+	struct sg2042_pwm_ddata *ddata = pwmchip_get_drvdata(chip);
+
+	pwm_sg2044_set_polarity(ddata, pwm, state);
+
+	pwm_set_dutycycle(chip, pwm, state);
+
+	/*
+	 * re-enable PWMSTART to refresh the register period
+	 */
+	pwm_sg2044_set_start(ddata, pwm, false);
+
+	if (!state->enabled)
+		return 0;
+
+	pwm_sg2044_set_outputdir(ddata, pwm, true);
+	pwm_sg2044_set_start(ddata, pwm, true);
+
+	return 0;
+}
+
+static const struct sg2042_chip_data sg2042_chip_data = {
+	.ops = {
+		.apply = pwm_sg2042_apply,
+		.get_state = pwm_sg2042_get_state,
+	}
+};
+
+static const struct sg2042_chip_data sg2044_chip_data = {
+	.ops = {
+		.apply = pwm_sg2044_apply,
+		.get_state = pwm_sg2042_get_state,
+	}
 };
 
 static const struct of_device_id sg2042_pwm_ids[] = {
-	{ .compatible = "sophgo,sg2042-pwm" },
+	{ .compatible = "sophgo,sg2042-pwm",
+	  .data = &sg2042_chip_data },
+	{ .compatible = "sophgo,sg2044-pwm",
+	  .data = &sg2044_chip_data },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, sg2042_pwm_ids);
 
 static int pwm_sg2042_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
+	const struct sg2042_chip_data *chip_data;
 	struct sg2042_pwm_ddata *ddata;
 	struct reset_control *rst;
 	struct pwm_chip *chip;
 	struct clk *clk;
 	int ret;
 
+	chip_data = device_get_match_data(dev);
+	if (!chip_data)
+		return -ENODEV;
+
 	chip = devm_pwmchip_alloc(dev, SG2042_PWM_CHANNELNUM, sizeof(*ddata));
 	if (IS_ERR(chip))
 		return PTR_ERR(chip);
@@ -170,7 +262,7 @@ static int pwm_sg2042_probe(struct platform_device *pdev)
 	if (IS_ERR(rst))
 		return dev_err_probe(dev, PTR_ERR(rst), "Failed to get reset\n");
 
-	chip->ops = &pwm_sg2042_ops;
+	chip->ops = &chip_data->ops;
 	chip->atomic = true;
 
 	ret = devm_pwmchip_add(dev, chip);
@@ -190,5 +282,6 @@ static struct platform_driver pwm_sg2042_driver = {
 module_platform_driver(pwm_sg2042_driver);
 
 MODULE_AUTHOR("Chen Wang");
+MODULE_AUTHOR("Longbin Li <looong.bin@gmail.com>");
 MODULE_DESCRIPTION("Sophgo SG2042 PWM driver");
 MODULE_LICENSE("GPL");