Tegra EHCI driver

Add generic access ops for controllers with a ulpi viewport register (e.g. Chipidea/ARC based controllers).

Signed-off-by Benoit Goby <[email protected]>

---
 drivers/usb/otg/Kconfig         |    7 ++++
 drivers/usb/otg/Makefile        |    1 +
 drivers/usb/otg/ulpi_viewport.c |   77 +++++++++++++++++++++++++++++++++++++++
 include/linux/usb/ulpi.h        |    5 +++
 4 files changed, 90 insertions(+), 0 deletions(-)
 create mode 100644 drivers/usb/otg/ulpi_viewport.c

drivers/usb/otg/Kconfig +7 -0

index 9ffc823..7702ee6 100644
@@ -49,6 +49,13 @@ config USB_ULPI
 	  Enable this to support ULPI connected USB OTG transceivers which
 	  are likely found on embedded boards.
 
+config USB_ULPI_VIEWPORT
+	bool
+	depends on USB_ULPI
+	help
+	  Provides read/write operations to the ULPI phy register set for
+	  controllers with a viewport register (e.g. Chipidea/ARC controllers).
+
 config TWL4030_USB
 	tristate "TWL4030 USB Transceiver Driver"
 	depends on TWL4030_CORE && REGULATOR_TWL4030

drivers/usb/otg/Makefile +1 -0

index a520e71..44581a9 100644
@@ -16,5 +16,6 @@ obj-$(CONFIG_TWL6030_USB)	+= twl6030-usb.o
 obj-$(CONFIG_USB_LANGWELL_OTG)	+= langwell_otg.o
 obj-$(CONFIG_NOP_USB_XCEIV)	+= nop-usb-xceiv.o
 obj-$(CONFIG_USB_ULPI)		+= ulpi.o
+obj-$(CONFIG_USB_ULPI_VIEWPORT)	+= ulpi_viewport.o
 obj-$(CONFIG_USB_MSM_OTG_72K)	+= msm72k_otg.o
 obj-$(CONFIG_AB8500_USB)	+= ab8500-usb.o

drivers/usb/otg/ulpi_viewport.c new file +17 -0

new file mode 100644
index 0000000..dd5dfae2
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2011 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/usb.h>
+#include <linux/io.h>

drivers/usb/otg/ulpi_viewport.c new file +23 -0

+	return -ETIMEDOUT;
+}
+
+static int ulpi_viewport_read(struct otg_transceiver *otg, u32 reg)
+{
+	int ret;
+	void __iomem *view = otg->io_priv;
+
+	writel(ULPI_VIEW_WAKEUP | ULPI_VIEW_WRITE, view);
+	ret = ulpi_viewport_wait(view, ULPI_VIEW_WAKEUP, 0);
+	if (ret)
+		return ret;
+
+	writel(ULPI_VIEW_RUN | ULPI_VIEW_READ | ULPI_VIEW_ADDR(reg), view);
+	ret = ulpi_viewport_wait(view, ULPI_VIEW_RUN, 0);
+	if (ret)
+		return ret;
+
+	return ULPI_VIEW_DATA_READ(readl(view));
+}
+
+static int ulpi_viewport_write(struct otg_transceiver *otg, u32 val, u32 reg)
+{

drivers/usb/otg/ulpi_viewport.c new file +7 -0

+	return ulpi_viewport_wait(view, ULPI_VIEW_RUN, 0);
+}
+
+struct otg_io_access_ops ulpi_viewport_access_ops = {
+	.read	= ulpi_viewport_read,
+	.write	= ulpi_viewport_write,
+};

include/linux/usb/ulpi.h +5 -0

index 82b1507..9595796 100644
@@ -184,4 +184,9 @@
 struct otg_transceiver *otg_ulpi_create(struct otg_io_access_ops *ops,
 					unsigned int flags);
 
+#ifdef CONFIG_USB_ULPI_VIEWPORT
+/* access ops for controllers with a viewport register */
+extern struct otg_io_access_ops ulpi_viewport_access_ops;
+#endif
+
 #endif /* __LINUX_USB_ULPI_H */

Hi,

Quoted 2 lines · Benoit Goby

Add generic access ops for controllers with a ulpi viewport register (e.g. Chipidea/ARC based controllers).

I can see mxc, msm and langwell are using the same bits (or at least some of them).

Is there some kind of specification for this ulpi viewport register?

Hi,

Quoted 2 lines · Igor Grinberg

Hi,

Quoted 6 lines · Benoit Goby

Quoted 2 lines

Add generic access ops for controllers with a ulpi viewport register (e.g. Chipidea/ARC based controllers).

I can see mxc, msm and langwell are using the same bits (or at least some of them).

They all use the Chipidea/ARC usb controllers.

Quoted 2 lines

Is there some kind of specification for this ulpi viewport register?

You can find the Chipidea/ARC datasheet in IMX35 datasheet ( got 0x0170 ULPI VIEWPORT) or a newer version (extra fields in some registers but miss 0x168-0x170) in
http://www.nxp.com/documents/user_manual/UM10314.pdf

Hi,

Quoted 6 lines · Matthieu CASTET

Hi,

Quoted 3 lines · Igor Grinberg

Hi,

On 02/18/11 05:42, Benoit Goby wrote:

Quoted 5 lines

Quoted 4 lines

Quoted 2 lines

Add generic access ops for controllers with a ulpi viewport register (e.g. Chipidea/ARC based controllers).

I can see mxc, msm and langwell are using the same bits (or at least some of them).

They all use the Chipidea/ARC usb controllers.

This means, that it is not generic, but Chipidea/ARC usb controller specific. And it is common to some/many platforms.

Can it be utilized on platforms that have another kind of ulpi access register?

Quoted 4 lines

Quoted 2 lines

Is there some kind of specification for this ulpi viewport register?

You can find the Chipidea/ARC datasheet in IMX35 datasheet ( got 0x0170 ULPI VIEWPORT) or a newer version (extra fields in some registers but miss 0x168-0x170) in
http://www.nxp.com/documents/user_manual/UM10314.pdf

I don't have the IMX35 datasheet which describes the USB OTG registers. The one that can be downloaded from Freescale website, only describes hardware and no ULPI viewport is mentioned there.

Quoted 14 lines · Igor Grinberg

Hi,

Quoted 10 lines · Matthieu CASTET

Hi,

Quoted 7 lines · Igor Grinberg

Hi,

Quoted 2 lines · Benoit Goby

Add generic access ops for controllers with a ulpi viewport register (e.g. Chipidea/ARC based controllers).

I can see mxc, msm and langwell are using the same bits (or at least some of them).

Quoted 4 lines

Quoted 1 line

They all use the Chipidea/ARC usb controllers.

This means, that it is not generic, but Chipidea/ARC usb controller specific. And it is common to some/many platforms.

Yes

Quoted 2 lines

Can it be utilized on platforms that have another kind of ulpi access register?

I don't think so

Quoted 9 lines

Quoted 5 lines

Quoted 3 lines

Is there some kind of specification for this ulpi viewport register?

You can find the Chipidea/ARC datasheet in IMX35 datasheet ( got 0x0170 ULPI VIEWPORT) or a newer version (extra fields in some registers but miss 0x168-0x170) in
http://www.nxp.com/documents/user_manual/UM10314.pdf

I don't have the IMX35 datasheet which describes the USB OTG registers. The one that can be downloaded from Freescale website, only describes hardware and no ULPI viewport is mentioned there.

From freescale.com I manage to download IMX35RM.pdf witch describe it (p2075).

I've looked into the IMX Reference Manual regarding the ulpi viewport register and it looks like these access ops can be utilized on another kind of ulpi access registers, as the same features are available in most (if not all) of ulpi access registers, whether they are called viewport or otherwise.
This will require much more thinking and may be the right solution would be multiple access ops files (e.g. drivers/usb/otg/ulpi_...port.c).
So for now, this patch is a good stuff to start from.

Benoit,

can you, please, address comments in my first reply?

Thanks.