[PATCH v3] OMAP2/3/4: PM: reset USB OTG module on boot

[PATCH v3] OMAP2/3/4: PM: reset USB OTG module on boot

[Kevin Hilman]

Rather than simply setting force-idle mode on boot, do a reset of the
OTG module.  This really ensures that any bootloader/bootstrap code
that leaves it active will not prevent future retention.  After reset,
OTG module will be in force-idle, force-standby mode.

In addition, ensure that the iclk is enabled before attempting a write
to the module SYSCONFIG register.

Problem reported by Mike Chan <mikechan@google.com>

Tested-by: Mike Chan <mikechan@google.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
---
Updates from v2
- reset for OMAP2 as well (needs update for OMAP4, see FIXME)

 arch/arm/mach-omap2/usb-musb.c |   37 +++++++++++++++++++++++++++++++++----
 1 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-omap2/usb-musb.c b/arch/arm/mach-omap2/usb-musb.c
index d85296d..1ea2ac7 100644
--- a/arch/arm/mach-omap2/usb-musb.c
+++ b/arch/arm/mach-omap2/usb-musb.c
@@ -26,18 +26,47 @@
 
 #include <linux/usb/musb.h>
 
+#include <asm/sizes.h>
+
 #include <mach/hardware.h>
 #include <mach/irqs.h>
 #include <mach/mux.h>
 #include <mach/usb.h>
 
-#define OTG_SYSCONFIG	(OMAP34XX_HSUSB_OTG_BASE + 0x404)
+#define OTG_SYSCONFIG	   0x404
+#define OTG_SYSC_SOFTRESET BIT(1)
 
 static void __init usb_musb_pm_init(void)
 {
-	/* Ensure force-idle mode for OTG controller */
-	if (cpu_is_omap34xx())
-		omap_writel(0, OTG_SYSCONFIG);
+	struct clk *iclk;
+	u32 phys_base;
+	void __iomem *otg_base;
+
+	if (cpu_is_omap243x())
+		phys_base = OMAP2_OTG_BASE;
+	else if (cpu_is_omap34xx())
+		phys_base = OMAP34XX_HSUSB_OTG_BASE;
+	else
+		/* FIXME: add OMAP4 support */
+		return;
+
+	otg_base = ioremap(phys_base, SZ_4K);
+	if (WARN_ON(!otg_base))
+		return;
+
+	iclk = clk_get(NULL, "hsotgusb_ick");
+	if (WARN_ON(!iclk))
+		return;
+
+	clk_enable(iclk);
+
+	/* Reset OTG controller.  After reset, it will be in
+	 * force-idle, force-standby mode. */
+	__raw_writel(OTG_SYSC_SOFTRESET, otg_base + OTG_SYSCONFIG);
+
+	clk_disable(iclk);
+	clk_put(iclk);
+	iounmap(otg_base);
 }
 
 #ifdef CONFIG_USB_MUSB_SOC
-- 
1.6.3.2

RE: [PATCH v3] OMAP2/3/4: PM: reset USB OTG module on boot

[Pandita, Vikram]

Kevin

>-----Original Message-----
>From: linux-omap-owner@vger.kernel.org [mailto:linux-omap-owner@vger.kernel.org] On Behalf Of Kevin
>Hilman
>Sent: Wednesday, June 24, 2009 1:28 PM
>To: linux-omap@vger.kernel.org
>Subject: [PATCH v3] OMAP2/3/4: PM: reset USB OTG module on boot
>

Have some more comments that I should have given before the re-spin v3 !!

>Rather than simply setting force-idle mode on boot, do a reset of the
>OTG module.  This really ensures that any bootloader/bootstrap code
>that leaves it active will not prevent future retention.  After reset,
>OTG module will be in force-idle, force-standby mode.
>
>In addition, ensure that the iclk is enabled before attempting a write
>to the module SYSCONFIG register.
>
>Problem reported by Mike Chan <mikechan@google.com>
>
>Tested-by: Mike Chan <mikechan@google.com>
>Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
>---
>Updates from v2
>- reset for OMAP2 as well (needs update for OMAP4, see FIXME)
>
> arch/arm/mach-omap2/usb-musb.c |   37 +++++++++++++++++++++++++++++++++----
> 1 files changed, 33 insertions(+), 4 deletions(-)
>
>diff --git a/arch/arm/mach-omap2/usb-musb.c b/arch/arm/mach-omap2/usb-musb.c
>index d85296d..1ea2ac7 100644
>--- a/arch/arm/mach-omap2/usb-musb.c
>+++ b/arch/arm/mach-omap2/usb-musb.c
>@@ -26,18 +26,47 @@
>
> #include <linux/usb/musb.h>
>
>+#include <asm/sizes.h>
>+
> #include <mach/hardware.h>
> #include <mach/irqs.h>
> #include <mach/mux.h>
> #include <mach/usb.h>
>
>-#define OTG_SYSCONFIG	(OMAP34XX_HSUSB_OTG_BASE + 0x404)
>+#define OTG_SYSCONFIG	   0x404
>+#define OTG_SYSC_SOFTRESET BIT(1)
>
> static void __init usb_musb_pm_init(void)
> {
>-	/* Ensure force-idle mode for OTG controller */
>-	if (cpu_is_omap34xx())
>-		omap_writel(0, OTG_SYSCONFIG);
>+	struct clk *iclk;
>+	u32 phys_base;
>+	void __iomem *otg_base;
>+
>+	if (cpu_is_omap243x())
>+		phys_base = OMAP2_OTG_BASE;
>+	else if (cpu_is_omap34xx())
>+		phys_base = OMAP34XX_HSUSB_OTG_BASE;
>+	else
>+		/* FIXME: add OMAP4 support */
>+		return;
>+
>+	otg_base = ioremap(phys_base, SZ_4K);
>+	if (WARN_ON(!otg_base))
>+		return;
>+
>+	iclk = clk_get(NULL, "hsotgusb_ick");
>+	if (WARN_ON(!iclk))

Need to iounmap(otg_base); and clk_put() in case of error
Goto error;
>+		return;
>+
>+	clk_enable(iclk);
>+
>+	/* Reset OTG controller.  After reset, it will be in
>+	 * force-idle, force-standby mode. */
>+	__raw_writel(OTG_SYSC_SOFTRESET, otg_base + OTG_SYSCONFIG);
>+
>+	clk_disable(iclk);

error:
>+	clk_put(iclk);
>+	iounmap(otg_base);
> }
>
> #ifdef CONFIG_USB_MUSB_SOC
>--
>1.6.3.2
>
>--
>To unsubscribe from this list: send the line "unsubscribe linux-omap" in
>the body of a message to majordomo@vger.kernel.org
>More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v3] OMAP2/3/4: PM: reset USB OTG module on boot

[Kevin Hilman]

"Pandita, Vikram" <vikram.pandita@ti.com> writes:

> Kevin
>
>>-----Original Message-----
>>From: linux-omap-owner@vger.kernel.org [mailto:linux-omap-owner@vger.kernel.org] On Behalf Of Kevin
>>Hilman
>>Sent: Wednesday, June 24, 2009 1:28 PM
>>To: linux-omap@vger.kernel.org
>>Subject: [PATCH v3] OMAP2/3/4: PM: reset USB OTG module on boot
>>
>
> Have some more comments that I should have given before the re-spin v3 !!
>

sigh, sending these too quickly... thanks for the reviews.

>>Rather than simply setting force-idle mode on boot, do a reset of the
>>OTG module.  This really ensures that any bootloader/bootstrap code
>>that leaves it active will not prevent future retention.  After reset,
>>OTG module will be in force-idle, force-standby mode.
>>
>>In addition, ensure that the iclk is enabled before attempting a write
>>to the module SYSCONFIG register.
>>
>>Problem reported by Mike Chan <mikechan@google.com>
>>
>>Tested-by: Mike Chan <mikechan@google.com>
>>Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
>>---
>>Updates from v2
>>- reset for OMAP2 as well (needs update for OMAP4, see FIXME)
>>
>> arch/arm/mach-omap2/usb-musb.c |   37 +++++++++++++++++++++++++++++++++----
>> 1 files changed, 33 insertions(+), 4 deletions(-)
>>
>>diff --git a/arch/arm/mach-omap2/usb-musb.c b/arch/arm/mach-omap2/usb-musb.c
>>index d85296d..1ea2ac7 100644
>>--- a/arch/arm/mach-omap2/usb-musb.c
>>+++ b/arch/arm/mach-omap2/usb-musb.c
>>@@ -26,18 +26,47 @@
>>
>> #include <linux/usb/musb.h>
>>
>>+#include <asm/sizes.h>
>>+
>> #include <mach/hardware.h>
>> #include <mach/irqs.h>
>> #include <mach/mux.h>
>> #include <mach/usb.h>
>>
>>-#define OTG_SYSCONFIG	(OMAP34XX_HSUSB_OTG_BASE + 0x404)
>>+#define OTG_SYSCONFIG	   0x404
>>+#define OTG_SYSC_SOFTRESET BIT(1)
>>
>> static void __init usb_musb_pm_init(void)
>> {
>>-	/* Ensure force-idle mode for OTG controller */
>>-	if (cpu_is_omap34xx())
>>-		omap_writel(0, OTG_SYSCONFIG);
>>+	struct clk *iclk;
>>+	u32 phys_base;
>>+	void __iomem *otg_base;
>>+
>>+	if (cpu_is_omap243x())
>>+		phys_base = OMAP2_OTG_BASE;
>>+	else if (cpu_is_omap34xx())
>>+		phys_base = OMAP34XX_HSUSB_OTG_BASE;
>>+	else
>>+		/* FIXME: add OMAP4 support */
>>+		return;
>>+
>>+	otg_base = ioremap(phys_base, SZ_4K);
>>+	if (WARN_ON(!otg_base))
>>+		return;
>>+
>>+	iclk = clk_get(NULL, "hsotgusb_ick");
>>+	if (WARN_ON(!iclk))
>
> Need to iounmap(otg_base); and clk_put() in case of error
> Goto error;

actually just need to iounmap in case clk_get fails.

>>+		return;
>>+
>>+	clk_enable(iclk);
>>+
>>+	/* Reset OTG controller.  After reset, it will be in
>>+	 * force-idle, force-standby mode. */
>>+	__raw_writel(OTG_SYSC_SOFTRESET, otg_base + OTG_SYSCONFIG);
>>+
>>+	clk_disable(iclk);
>
> error:
>>+	clk_put(iclk);

and error: should go here.

>>+	iounmap(otg_base);
>> }
>>
>> #ifdef CONFIG_USB_MUSB_SOC
>>--
>>1.6.3.2
>>
>>--
>>To unsubscribe from this list: send the line "unsubscribe linux-omap" in
>>the body of a message to majordomo@vger.kernel.org
>>More majordomo info at  http://vger.kernel.org/majordomo-info.html