diff --git a/arch/arm/mach-omap2/clock3xxx_data.c b/arch/arm/mach-omap2/clock3xxx_data.c
index 58c6e477a4f1..4a3c1c819adc 100644
--- a/arch/arm/mach-omap2/clock3xxx_data.c
+++ b/arch/arm/mach-omap2/clock3xxx_data.c
@@ -3201,8 +3201,12 @@ static struct clk vpfe_fck = {
 };
 
 /*
- * The UART1/2 functional clock acts as the functional
- * clock for UART4. No separate fclk control available.
+ * The UART1/2 functional clock acts as the functional clock for
+ * UART4. No separate fclk control available.  XXX Well now we have a
+ * uart4_fck that is apparently used as the UART4 functional clock,
+ * but it also seems that uart1_fck or uart2_fck are still needed, at
+ * least for UART4 softresets to complete.  This really needs
+ * clarification.
  */
 static struct clk uart4_ick_am35xx = {
 	.name		= "uart4_ick",
diff --git a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
index 2f4889e514e5..1120d388eca3 100644
--- a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
@@ -536,6 +536,20 @@ static struct omap_hwmod_dma_info am35xx_uart4_sdma_reqs[] = {
 	{ .dma_req = -1 }
 };
 
+/*
+ * XXX AM35xx UART4 cannot complete its softreset without uart1_fck or
+ * uart2_fck being enabled.  So we add uart1_fck as an optional clock,
+ * below, and set the HWMOD_CONTROL_OPT_CLKS_IN_RESET.  This really
+ * should not be needed.  The functional clock structure of the AM35xx
+ * UART4 is extremely unclear and opaque; it is unclear what the role
+ * of uart1/2_fck is for the UART4.  Any clarification from either
+ * empirical testing or the AM3505/3517 hardware designers would be
+ * most welcome.
+ */
+static struct omap_hwmod_opt_clk am35xx_uart4_opt_clks[] = {
+	{ .role = "softreset_uart1_fck", .clk = "uart1_fck" },
+};
+
 static struct omap_hwmod am35xx_uart4_hwmod = {
 	.name		= "uart4",
 	.mpu_irqs	= am35xx_uart4_mpu_irqs,
@@ -550,6 +564,9 @@ static struct omap_hwmod am35xx_uart4_hwmod = {
 			.idlest_idle_bit = AM35XX_ST_UART4_SHIFT,
 		},
 	},
+	.opt_clks	= am35xx_uart4_opt_clks,
+	.opt_clks_cnt	= ARRAY_SIZE(am35xx_uart4_opt_clks),
+	.flags		= HWMOD_CONTROL_OPT_CLKS_IN_RESET,
 	.class		= &omap2_uart_class,
 };