Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/drivers/rtc/rtc-sun6i.c b/drivers/rtc/rtc-sun6i.c
index 5e2bd9f..c41bc80 100644
--- a/drivers/rtc/rtc-sun6i.c
+++ b/drivers/rtc/rtc-sun6i.c
@@ -276,7 +276,7 @@ static void __init sun6i_rtc_clk_init(struct device_node *node,
 								300000000);
 	if (IS_ERR(rtc->int_osc)) {
 		pr_crit("Couldn't register the internal oscillator\n");
-		return;
+		goto err;
 	}
 
 	parents[0] = clk_hw_get_name(rtc->int_osc);
@@ -292,7 +292,7 @@ static void __init sun6i_rtc_clk_init(struct device_node *node,
 	rtc->losc = clk_register(NULL, &rtc->hw);
 	if (IS_ERR(rtc->losc)) {
 		pr_crit("Couldn't register the LOSC clock\n");
-		return;
+		goto err_register;
 	}
 
 	of_property_read_string_index(node, "clock-output-names", 1,
@@ -303,7 +303,7 @@ static void __init sun6i_rtc_clk_init(struct device_node *node,
 					  &rtc->lock);
 	if (IS_ERR(rtc->ext_losc)) {
 		pr_crit("Couldn't register the LOSC external gate\n");
-		return;
+		goto err_register;
 	}
 
 	clk_data->num = 2;
@@ -316,6 +316,8 @@ static void __init sun6i_rtc_clk_init(struct device_node *node,
 	of_clk_add_hw_provider(node, of_clk_hw_onecell_get, clk_data);
 	return;
 
+err_register:
+	clk_hw_unregister_fixed_rate(rtc->int_osc);
 err:
 	kfree(clk_data);
 }
@@ -380,6 +382,22 @@ static void __init sun50i_h6_rtc_clk_init(struct device_node *node)
 CLK_OF_DECLARE_DRIVER(sun50i_h6_rtc_clk, "allwinner,sun50i-h6-rtc",
 		      sun50i_h6_rtc_clk_init);
 
+/*
+ * The R40 user manual is self-conflicting on whether the prescaler is
+ * fixed or configurable. The clock diagram shows it as fixed, but there
+ * is also a configurable divider in the RTC block.
+ */
+static const struct sun6i_rtc_clk_data sun8i_r40_rtc_data = {
+	.rc_osc_rate = 16000000,
+	.fixed_prescaler = 512,
+};
+static void __init sun8i_r40_rtc_clk_init(struct device_node *node)
+{
+	sun6i_rtc_clk_init(node, &sun8i_r40_rtc_data);
+}
+CLK_OF_DECLARE_DRIVER(sun8i_r40_rtc_clk, "allwinner,sun8i-r40-rtc",
+		      sun8i_r40_rtc_clk_init);
+
 static const struct sun6i_rtc_clk_data sun8i_v3_rtc_data = {
 	.rc_osc_rate = 32000,
 	.has_out_clk = 1,