[PATCH 0/2 v2] S3C64XX: Fix 48M clock enable

[PATCH 0/2 v2] S3C64XX: Fix 48M clock enable

[Paulius Zaleckas]

To enable 48M clock USB PHY must be initialized since 48M
is output of USB PHY PLL.
So fix a problem where other devices requiring 48M clock will
not work unless USB OTG driver is enabled.
is_osc was removed from OTG drivers platform data and implemented
as separate function s3c6400_clk_xusbxti_is_osc which should be
called from machine_init. Currently there is no in-kernel users
of it.

This fix is only for S3C64xx family, but I am sure something
similar will be needed for S5P family. I have started the work
but I am unable to finnish it since I only have datasheet for
S5PC100. Maybe Samsung guys could help me with this..?
However current patches doesn't break S5P since it is not
using s3c-hsotg driver (yet?).

---

Paulius Zaleckas (2):
      USB: s3-hsotg: Remove PHY initialization code and use CLK API
      [v2]ARM: S3C64XX: Fix USB and 48M clock enable procedure


 arch/arm/mach-s3c64xx/clock.c               |   67 ++++++++++++++++++-
 arch/arm/plat-samsung/include/plat/clock.h  |    2 +
 arch/arm/plat-samsung/include/plat/udc-hs.h |    2 -
 drivers/usb/gadget/s3c-hsotg.c              |   94 +++++----------------------
 4 files changed, 79 insertions(+), 86 deletions(-)

[PATCH 1/2] [v2]ARM: S3C64XX: Fix USB and 48M clock enable procedure

[Paulius Zaleckas]

48M clock is output from USB PHY PLL. To enable 48M clock
we must initialize USB PHY.

changes since v1:
- renamed s3c64xx_clk_xusbxti_is_osc() to s3c64xx_clk_xusbxti_set_osc()

Signed-off-by: Paulius Zaleckas <paulius.zaleckas@gmail.com>
---

 arch/arm/mach-s3c64xx/clock.c              |   67 +++++++++++++++++++++++++---
 arch/arm/plat-samsung/include/plat/clock.h |    2 +
 2 files changed, 63 insertions(+), 6 deletions(-)

diff --git a/arch/arm/mach-s3c64xx/clock.c b/arch/arm/mach-s3c64xx/clock.c
index 7e03f0a..71131f7 100644
--- a/arch/arm/mach-s3c64xx/clock.c
+++ b/arch/arm/mach-s3c64xx/clock.c
@@ -19,6 +19,7 @@
 #include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/io.h>
+#include <linux/delay.h>
 
 #include <mach/hardware.h>
 #include <mach/map.h>
@@ -32,6 +33,7 @@
 #include <plat/cpu-freq.h>
 #include <plat/clock.h>
 #include <plat/clock-clksrc.h>
+#include <plat/regs-usb-hsotg-phy.h>
 
 /* fin_apll, fin_mpll and fin_epll are all the same clock, which we call
  * ext_xtal_mux for want of an actual name from the manual.
@@ -61,7 +63,20 @@ struct clk clk_27m = {
 	.rate		= 27000000,
 };
 
-static int clk_48m_ctrl(struct clk *clk, int enable)
+void __init s3c64xx_clk_xusbxti_set_osc(int is_osc)
+{
+	u32 val;
+
+	/* no need to protect since it will be called from machine init */
+	val = __raw_readl(S3C_PHYCLK);
+	if (is_osc)
+		val |= S3C_PHYCLK_EXT_OSC;
+	else
+		val &= ~S3C_PHYCLK_EXT_OSC;
+	__raw_writel(val, S3C_PHYCLK);
+}
+
+static int clk_xusbxti_ctrl(struct clk *clk, int enable)
 {
 	unsigned long flags;
 	u32 val;
@@ -76,22 +91,62 @@ static int clk_48m_ctrl(struct clk *clk, int enable)
 		val &= ~S3C64XX_OTHERS_USBMASK;
 
 	__raw_writel(val, S3C64XX_OTHERS);
+
+	val = __raw_readl(S3C_PHYPWR);
+	if (enable)
+		val &= ~(SRC_PHYPWR_OTG_DISABLE | SRC_PHYPWR_ANALOG_POWERDOWN |
+			 SRC_PHYPWR_FORCE_SUSPEND);
+	else
+		val |= (SRC_PHYPWR_OTG_DISABLE | SRC_PHYPWR_ANALOG_POWERDOWN |
+			SRC_PHYPWR_FORCE_SUSPEND);
+	__raw_writel(val, S3C_PHYPWR);
+	mdelay(1);
+
+	if (enable) {
+		val = __raw_readl(S3C_PHYCLK);
+
+		val &= ~S3C_PHYCLK_CLKSEL_MASK;
+
+		switch (clk->rate) {
+		case 12*MHZ:
+			val |= S3C_PHYCLK_CLKSEL_12M;
+			break;
+		case 24*MHZ:
+			val |= S3C_PHYCLK_CLKSEL_24M;
+			break;
+		default:
+			pr_err("Invalid USB PHY external clock frequency: %lu\n",
+			       clk->rate);
+		case 48*MHZ:
+			/* default reference clock */
+			break;
+		}
+
+		__raw_writel(val | S3C_PHYCLK_CLK_FORCE, S3C_PHYCLK);
+
+		/* issue a full set of resets to the otg and core */
+		__raw_writel(S3C_RSTCON_PHY, S3C_RSTCON);
+		udelay(20);	/* at-least 10uS */
+		__raw_writel(0, S3C_RSTCON);
+	}
+
 	local_irq_restore(flags);
 
 	return 0;
 }
 
-struct clk clk_48m = {
-	.name		= "clk_48m",
+struct clk clk_xusbxti = {
+	.name		= "xusbxti",
 	.id		= -1,
 	.rate		= 48000000,
-	.enable		= clk_48m_ctrl,
+	.enable		= clk_xusbxti_ctrl,
 };
 
-struct clk clk_xusbxti = {
-	.name		= "xusbxti",
+struct clk clk_48m = {
+	.name		= "clk_48m",
 	.id		= -1,
 	.rate		= 48000000,
+	.parent		= &clk_xusbxti,
 };
 
 static int inline s3c64xx_gate(void __iomem *reg,
diff --git a/arch/arm/plat-samsung/include/plat/clock.h b/arch/arm/plat-samsung/include/plat/clock.h
index 0fbcd0e..ed6f6fa 100644
--- a/arch/arm/plat-samsung/include/plat/clock.h
+++ b/arch/arm/plat-samsung/include/plat/clock.h
@@ -76,6 +76,8 @@ extern struct clk clk_27m;
 extern struct clk clk_48m;
 extern struct clk clk_xusbxti;
 
+extern void s3c64xx_clk_xusbxti_set_osc(int is_osc);
+
 extern int clk_default_setrate(struct clk *clk, unsigned long rate);
 extern struct clk_ops clk_ops_def_setrate;
 

[PATCH 2/2] USB: s3-hsotg: Remove PHY initialization code and use CLK API

[Paulius Zaleckas]

All USB PHY initialization now is handled hy xusbxti clock
enable procedure.

Signed-off-by: Paulius Zaleckas <paulius.zaleckas@gmail.com>
---

 arch/arm/plat-samsung/include/plat/udc-hs.h |    2 -
 drivers/usb/gadget/s3c-hsotg.c              |   94 +++++----------------------
 2 files changed, 16 insertions(+), 80 deletions(-)

diff --git a/arch/arm/plat-samsung/include/plat/udc-hs.h b/arch/arm/plat-samsung/include/plat/udc-hs.h
index a22a4f2..a8221cf 100644
--- a/arch/arm/plat-samsung/include/plat/udc-hs.h
+++ b/arch/arm/plat-samsung/include/plat/udc-hs.h
@@ -21,9 +21,7 @@ enum s3c_hsotg_dmamode {
 /**
  * struct s3c_hsotg_plat - platform data for high-speed otg/udc
  * @dma: Whether to use DMA or not.
- * @is_osc: The clock source is an oscillator, not a crystal
  */
 struct s3c_hsotg_plat {
 	enum s3c_hsotg_dmamode	dma;
-	unsigned int		is_osc : 1;
 };
diff --git a/drivers/usb/gadget/s3c-hsotg.c b/drivers/usb/gadget/s3c-hsotg.c
index a229744..129e6ff 100644
--- a/drivers/usb/gadget/s3c-hsotg.c
+++ b/drivers/usb/gadget/s3c-hsotg.c
@@ -151,6 +151,7 @@ struct s3c_hsotg {
 	struct resource		*regs_res;
 	int			irq;
 	struct clk		*clk;
+	struct clk		*phy_clk;
 
 	unsigned int		dedicated_fifos:1;
 
@@ -2791,51 +2792,6 @@ static void __devinit s3c_hsotg_initep(struct s3c_hsotg *hsotg,
 	}
 }
 
-/**
- * s3c_hsotg_otgreset - reset the OtG phy block
- * @hsotg: The host state.
- *
- * Power up the phy, set the basic configuration and start the PHY.
- */
-static void s3c_hsotg_otgreset(struct s3c_hsotg *hsotg)
-{
-	struct clk *xusbxti;
-	u32 pwr, osc;
-
-	pwr = readl(S3C_PHYPWR);
-	pwr &= ~0x19;
-	writel(pwr, S3C_PHYPWR);
-	mdelay(1);
-
-	osc = hsotg->plat->is_osc ? S3C_PHYCLK_EXT_OSC : 0;
-
-	xusbxti = clk_get(hsotg->dev, "xusbxti");
-	if (xusbxti && !IS_ERR(xusbxti)) {
-		switch (clk_get_rate(xusbxti)) {
-		case 12*MHZ:
-			osc |= S3C_PHYCLK_CLKSEL_12M;
-			break;
-		case 24*MHZ:
-			osc |= S3C_PHYCLK_CLKSEL_24M;
-			break;
-		default:
-		case 48*MHZ:
-			/* default reference clock */
-			break;
-		}
-		clk_put(xusbxti);
-	}
-
-	writel(osc | 0x10, S3C_PHYCLK);
-
-	/* issue a full set of resets to the otg and core */
-
-	writel(S3C_RSTCON_PHY, S3C_RSTCON);
-	udelay(20);	/* at-least 10uS */
-	writel(0, S3C_RSTCON);
-}
-
-
 static void s3c_hsotg_init(struct s3c_hsotg *hsotg)
 {
 	u32 cfg4;
@@ -3206,32 +3162,6 @@ static void __devexit s3c_hsotg_delete_debug(struct s3c_hsotg *hsotg)
 	debugfs_remove(hsotg->debug_root);
 }
 
-/**
- * s3c_hsotg_gate - set the hardware gate for the block
- * @pdev: The device we bound to
- * @on: On or off.
- *
- * Set the hardware gate setting into the block. If we end up on
- * something other than an S3C64XX, then we might need to change this
- * to using a platform data callback, or some other mechanism.
- */
-static void s3c_hsotg_gate(struct platform_device *pdev, bool on)
-{
-	unsigned long flags;
-	u32 others;
-
-	local_irq_save(flags);
-
-	others = __raw_readl(S3C64XX_OTHERS);
-	if (on)
-		others |= S3C64XX_OTHERS_USBMASK;
-	else
-		others &= ~S3C64XX_OTHERS_USBMASK;
-	__raw_writel(others, S3C64XX_OTHERS);
-
-	local_irq_restore(flags);
-}
-
 static struct s3c_hsotg_plat s3c_hsotg_default_pdata;
 
 static int __devinit s3c_hsotg_probe(struct platform_device *pdev)
@@ -3257,20 +3187,27 @@ static int __devinit s3c_hsotg_probe(struct platform_device *pdev)
 	hsotg->dev = dev;
 	hsotg->plat = plat;
 
-	hsotg->clk = clk_get(&pdev->dev, "otg");
+	hsotg->clk = clk_get(dev, "otg");
 	if (IS_ERR(hsotg->clk)) {
 		dev_err(dev, "cannot get otg clock\n");
 		ret = -EINVAL;
 		goto err_mem;
 	}
 
+	hsotg->phy_clk = clk_get(dev, "xusbxti");
+	if (IS_ERR(hsotg->phy_clk)) {
+		dev_err(dev, "cannot get xusbxti clock\n");
+		ret = -EINVAL;
+		goto err_clk;
+	}
+
 	platform_set_drvdata(pdev, hsotg);
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res) {
 		dev_err(dev, "cannot find register resource 0\n");
 		ret = -EINVAL;
-		goto err_clk;
+		goto err_phy_clk;
 	}
 
 	hsotg->regs_res = request_mem_region(res->start, resource_size(res),
@@ -3278,7 +3215,7 @@ static int __devinit s3c_hsotg_probe(struct platform_device *pdev)
 	if (!hsotg->regs_res) {
 		dev_err(dev, "cannot reserve registers\n");
 		ret = -ENOENT;
-		goto err_clk;
+		goto err_phy_clk;
 	}
 
 	hsotg->regs = ioremap(res->start, resource_size(res));
@@ -3332,10 +3269,8 @@ static int __devinit s3c_hsotg_probe(struct platform_device *pdev)
 	/* reset the system */
 
 	clk_enable(hsotg->clk);
+	clk_enable(hsotg->phy_clk);
 
-	s3c_hsotg_gate(pdev, true);
-
-	s3c_hsotg_otgreset(hsotg);
 	s3c_hsotg_corereset(hsotg);
 	s3c_hsotg_init(hsotg);
 
@@ -3356,6 +3291,8 @@ err_regs:
 err_regs_res:
 	release_resource(hsotg->regs_res);
 	kfree(hsotg->regs_res);
+err_phy_clk:
+	clk_put(hsotg->phy_clk);
 err_clk:
 	clk_put(hsotg->clk);
 err_mem:
@@ -3377,7 +3314,8 @@ static int __devexit s3c_hsotg_remove(struct platform_device *pdev)
 	release_resource(hsotg->regs_res);
 	kfree(hsotg->regs_res);
 
-	s3c_hsotg_gate(pdev, false);
+	clk_disable(hsotg->phy_clk);
+	clk_put(hsotg->phy_clk);
 
 	clk_disable(hsotg->clk);
 	clk_put(hsotg->clk);

[PATCH 0/2 v2] S3C64XX: Fix 48M clock enable

[Marek Szyprowski]

Hello,

On Tuesday, October 12, 2010 2:41 PM Paulius Zaleckas wrote:

> To enable 48M clock USB PHY must be initialized since 48M
> is output of USB PHY PLL.
> So fix a problem where other devices requiring 48M clock will
> not work unless USB OTG driver is enabled.
> is_osc was removed from OTG drivers platform data and implemented
> as separate function s3c6400_clk_xusbxti_is_osc which should be
> called from machine_init. Currently there is no in-kernel users
> of it.
> 
> This fix is only for S3C64xx family, but I am sure something
> similar will be needed for S5P family. I have started the work
> but I am unable to finnish it since I only have datasheet for
> S5PC100. Maybe Samsung guys could help me with this..?
> However current patches doesn't break S5P since it is not
> using s3c-hsotg driver (yet?).

There are patches that enables the driver on S5PC110/S5PV210 series
on kgene/for-next tree. Please note that at least Samsung Goni and
Samsung Aquila uses external oscillator to supply usb clock. Please
refer to:

http://git.kernel.org/?p=linux/kernel/git/kgene/linux-samsung.git;a=commit;h=e5e044e637228be8bdf033c0772f9e5926269ae0
http://git.kernel.org/?p=linux/kernel/git/kgene/linux-samsung.git;a=commit;h=a33bc34103b4fc4eca13cdd61f2579857797bbf7

Best regards
--
Marek Szyprowski
Samsung Poland R&D Center

[PATCH 0/2 v2] S3C64XX: Fix 48M clock enable

[Paulius Zaleckas]

On Tue, Oct 12, 2010 at 3:55 PM, Marek Szyprowski
<m.szyprowski@samsung.com> wrote:
> Hello,
>
> On Tuesday, October 12, 2010 2:41 PM Paulius Zaleckas wrote:
>
>> To enable 48M clock USB PHY must be initialized since 48M
>> is output of USB PHY PLL.
>> So fix a problem where other devices requiring 48M clock will
>> not work unless USB OTG driver is enabled.
>> is_osc was removed from OTG drivers platform data and implemented
>> as separate function s3c6400_clk_xusbxti_is_osc which should be
>> called from machine_init. Currently there is no in-kernel users
>> of it.
>>
>> This fix is only for S3C64xx family, but I am sure something
>> similar will be needed for S5P family. I have started the work
>> but I am unable to finnish it since I only have datasheet for
>> S5PC100. Maybe Samsung guys could help me with this..?
>> However current patches doesn't break S5P since it is not
>> using s3c-hsotg driver (yet?).
>
> There are patches that enables the driver on S5PC110/S5PV210 series
> on kgene/for-next tree. Please note that at least Samsung Goni and
> Samsung Aquila uses external oscillator to supply usb clock. Please
> refer to:
>
> http://git.kernel.org/?p=linux/kernel/git/kgene/linux-samsung.git;a=commit;h=e5e044e637228be8bdf033c0772f9e5926269ae0

Interesting patch... If Goni uses oscillator then it will fail with current
otg driver since it will configure phy for crystal, because is_otg is not set
in the platform data.

> http://git.kernel.org/?p=linux/kernel/git/kgene/linux-samsung.git;a=commit;h=a33bc34103b4fc4eca13cdd61f2579857797bbf7

This patch contains some really nasty workaround for S3C64XX_OTHERS
Mine version allows to get rid of it.

I have some preliminary version of patch for s5p. I will send it to you in
the evening.

[PATCH 0/2 v2] S3C64XX: Fix 48M clock enable

[Marek Szyprowski]

Hello,

On Tuesday, October 12, 2010 3:49 PM Paulius Zaleckas wrote:

> >> To enable 48M clock USB PHY must be initialized since 48M
> >> is output of USB PHY PLL.
> >> So fix a problem where other devices requiring 48M clock will
> >> not work unless USB OTG driver is enabled.
> >> is_osc was removed from OTG drivers platform data and implemented
> >> as separate function s3c6400_clk_xusbxti_is_osc which should be
> >> called from machine_init. Currently there is no in-kernel users
> >> of it.
> >>
> >> This fix is only for S3C64xx family, but I am sure something
> >> similar will be needed for S5P family. I have started the work
> >> but I am unable to finnish it since I only have datasheet for
> >> S5PC100. Maybe Samsung guys could help me with this..?
> >> However current patches doesn't break S5P since it is not
> >> using s3c-hsotg driver (yet?).
> >
> > There are patches that enables the driver on S5PC110/S5PV210 series
> > on kgene/for-next tree. Please note that at least Samsung Goni and
> > Samsung Aquila uses external oscillator to supply usb clock. Please
> > refer to:
> >
> > http://git.kernel.org/?p=linux/kernel/git/kgene/linux-
> samsung.git;a=commit;h=e5e044e637228be8bdf033c0772f9e5926269ae0
> 
> Interesting patch... If Goni uses oscillator then it will fail with current
> otg driver since it will configure phy for crystal, because is_otg is not set
> in the platform data.

Right, but the interesting is that fact that it was working. I will check it
tomorrow again.

> > http://git.kernel.org/?p=linux/kernel/git/kgene/linux-
> samsung.git;a=commit;h=a33bc34103b4fc4eca13cdd61f2579857797bbf7
> 
> This patch contains some really nasty workaround for S3C64XX_OTHERS
> Mine version allows to get rid of it.

Right that approach was a hack. I really like the idea behind your patch.

> I have some preliminary version of patch for s5p. I will send it to you in
> the evening.

Ok, I will check it tomorrow.

Best regards
--
Marek Szyprowski
Samsung Poland R&D Center