Update Linux to v5.10.157

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.157.tar.xz

Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
Change-Id: I7b30d9e98d8c465d6b44de8e7433b4a40b3289ba
diff --git a/drivers/pwm/pwm-sifive.c b/drivers/pwm/pwm-sifive.c
index 2485fba..9cc0612 100644
--- a/drivers/pwm/pwm-sifive.c
+++ b/drivers/pwm/pwm-sifive.c
@@ -23,7 +23,7 @@
 #define PWM_SIFIVE_PWMCFG		0x0
 #define PWM_SIFIVE_PWMCOUNT		0x8
 #define PWM_SIFIVE_PWMS			0x10
-#define PWM_SIFIVE_PWMCMP0		0x20
+#define PWM_SIFIVE_PWMCMP(i)		(0x20 + 4 * (i))
 
 /* PWMCFG fields */
 #define PWM_SIFIVE_PWMCFG_SCALE		GENMASK(3, 0)
@@ -36,8 +36,6 @@
 #define PWM_SIFIVE_PWMCFG_GANG		BIT(24)
 #define PWM_SIFIVE_PWMCFG_IP		BIT(28)
 
-/* PWM_SIFIVE_SIZE_PWMCMP is used to calculate offset for pwmcmpX registers */
-#define PWM_SIFIVE_SIZE_PWMCMP		4
 #define PWM_SIFIVE_CMPWIDTH		16
 #define PWM_SIFIVE_DEFAULT_PERIOD	10000000
 
@@ -112,8 +110,7 @@
 	struct pwm_sifive_ddata *ddata = pwm_sifive_chip_to_ddata(chip);
 	u32 duty, val;
 
-	duty = readl(ddata->regs + PWM_SIFIVE_PWMCMP0 +
-		     pwm->hwpwm * PWM_SIFIVE_SIZE_PWMCMP);
+	duty = readl(ddata->regs + PWM_SIFIVE_PWMCMP(pwm->hwpwm));
 
 	state->enabled = duty > 0;
 
@@ -194,8 +191,7 @@
 		pwm_sifive_update_clock(ddata, clk_get_rate(ddata->clk));
 	}
 
-	writel(frac, ddata->regs + PWM_SIFIVE_PWMCMP0 +
-	       pwm->hwpwm * PWM_SIFIVE_SIZE_PWMCMP);
+	writel(frac, ddata->regs + PWM_SIFIVE_PWMCMP(pwm->hwpwm));
 
 	if (state->enabled != enabled)
 		pwm_sifive_enable(chip, state->enabled);
@@ -234,6 +230,8 @@
 	struct pwm_chip *chip;
 	struct resource *res;
 	int ret;
+	u32 val;
+	unsigned int enabled_pwms = 0, enabled_clks = 1;
 
 	ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
 	if (!ddata)
@@ -264,6 +262,33 @@
 		return ret;
 	}
 
+	val = readl(ddata->regs + PWM_SIFIVE_PWMCFG);
+	if (val & PWM_SIFIVE_PWMCFG_EN_ALWAYS) {
+		unsigned int i;
+
+		for (i = 0; i < chip->npwm; ++i) {
+			val = readl(ddata->regs + PWM_SIFIVE_PWMCMP(i));
+			if (val > 0)
+				++enabled_pwms;
+		}
+	}
+
+	/* The clk should be on once for each running PWM. */
+	if (enabled_pwms) {
+		while (enabled_clks < enabled_pwms) {
+			/* This is not expected to fail as the clk is already on */
+			ret = clk_enable(ddata->clk);
+			if (unlikely(ret)) {
+				dev_err_probe(dev, ret, "Failed to enable clk\n");
+				goto disable_clk;
+			}
+			++enabled_clks;
+		}
+	} else {
+		clk_disable(ddata->clk);
+		enabled_clks = 0;
+	}
+
 	/* Watch for changes to underlying clock frequency */
 	ddata->notifier.notifier_call = pwm_sifive_clock_notifier;
 	ret = clk_notifier_register(ddata->clk, &ddata->notifier);
@@ -286,7 +311,11 @@
 unregister_clk:
 	clk_notifier_unregister(ddata->clk, &ddata->notifier);
 disable_clk:
-	clk_disable_unprepare(ddata->clk);
+	while (enabled_clks) {
+		clk_disable(ddata->clk);
+		--enabled_clks;
+	}
+	clk_unprepare(ddata->clk);
 
 	return ret;
 }
@@ -294,25 +323,21 @@
 static int pwm_sifive_remove(struct platform_device *dev)
 {
 	struct pwm_sifive_ddata *ddata = platform_get_drvdata(dev);
-	bool is_enabled = false;
 	struct pwm_device *pwm;
-	int ret, ch;
+	int ch;
+
+	pwmchip_remove(&ddata->chip);
+	clk_notifier_unregister(ddata->clk, &ddata->notifier);
 
 	for (ch = 0; ch < ddata->chip.npwm; ch++) {
 		pwm = &ddata->chip.pwms[ch];
-		if (pwm->state.enabled) {
-			is_enabled = true;
-			break;
-		}
+		if (pwm->state.enabled)
+			clk_disable(ddata->clk);
 	}
-	if (is_enabled)
-		clk_disable(ddata->clk);
 
-	clk_disable_unprepare(ddata->clk);
-	ret = pwmchip_remove(&ddata->chip);
-	clk_notifier_unregister(ddata->clk, &ddata->notifier);
+	clk_unprepare(ddata->clk);
 
-	return ret;
+	return 0;
 }
 
 static const struct of_device_id pwm_sifive_of_match[] = {