[PATCH] USB: OHCI: make ohci-da8xx a separate driver

From: ahaslam
Date: Wed Oct 26 2016 - 17:08:28 EST

From: Manjunath Goudar <manjunath.goudar@xxxxxxxxxx>

Separate the Davinci OHCI host controller driver from ohci-hcd
host code so that it can be built as a separate driver module.
This work is part of enabling multi-platform kernels on ARM

Signed-off-by: Manjunath Goudar <manjunath.goudar@xxxxxxxxxx>
[Axel: adapted and rebased, fixed minor comments]
Signed-off-by: Axel Haslam <ahaslam@xxxxxxxxxxxx>
---

This was a previews patch submited by Manjunath [1]
that was never taken in because of an undefined symbol
when loading as a module. That symbol is not present anymore
so we can safly build the driver as a module.

I rebased, fixing the minor remaining comments.

Axel.
http://patches.linaro.org/patch/18234/

drivers/usb/host/Kconfig | 4 +-
drivers/usb/host/Makefile | 1 +
drivers/usb/host/ohci-da8xx.c | 181 +++++++++++++++++-------------------------
drivers/usb/host/ohci-hcd.c | 18 -----
4 files changed, 74 insertions(+), 130 deletions(-)

diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index 83b6cec..6361fc7 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -479,9 +479,9 @@ config USB_OHCI_HCD_OMAP3
OMAP3 and later chips.

config USB_OHCI_HCD_DAVINCI
- bool "OHCI support for TI DaVinci DA8xx"
+ tristate "OHCI support for TI DaVinci DA8xx"
depends on ARCH_DAVINCI_DA8XX
- depends on USB_OHCI_HCD=y
+ depends on USB_OHCI_HCD
select PHY_DA8XX_USB
default y
help
diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
index 6ef785b..2644537 100644
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -61,6 +61,7 @@ obj-$(CONFIG_USB_OHCI_HCD_AT91) += ohci-at91.o
obj-$(CONFIG_USB_OHCI_HCD_S3C2410) += ohci-s3c2410.o
obj-$(CONFIG_USB_OHCI_HCD_LPC32XX) += ohci-nxp.o
obj-$(CONFIG_USB_OHCI_HCD_PXA27X) += ohci-pxa27x.o
+obj-$(CONFIG_USB_OHCI_HCD_DAVINCI) += ohci-da8xx.o

obj-$(CONFIG_USB_UHCI_HCD) += uhci-hcd.o
obj-$(CONFIG_USB_FHCI_HCD) += fhci.o
diff --git a/drivers/usb/host/ohci-da8xx.c b/drivers/usb/host/ohci-da8xx.c
index 3656d7c..4e2a61f 100644
--- a/drivers/usb/host/ohci-da8xx.c
+++ b/drivers/usb/host/ohci-da8xx.c
@@ -11,16 +11,30 @@
* kind, whether express or implied.
*/

+#include <linux/clk.h>
+#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
#include <linux/platform_device.h>
-#include <linux/clk.h>
#include <linux/phy/phy.h>
#include <linux/platform_data/usb-davinci.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+#include <asm/unaligned.h>

-#ifndef CONFIG_ARCH_DAVINCI_DA8XX
-#error "This file is DA8xx bus glue. Define CONFIG_ARCH_DAVINCI_DA8XX."
-#endif
+#include "ohci.h"
+
+#define DRIVER_DESC "DA8XX"
+
+static const char hcd_name[] = "ohci";
+
+static struct hc_driver __read_mostly ohci_da8xx_hc_driver;
+
+static int (*orig_ohci_hub_control)(struct usb_hcd *hcd, u16 typeReq,
+ u16 wValue, u16 wIndex, char *buf, u16 wLength);
+static int (*orig_ohci_hub_status_data)(struct usb_hcd *hcd, char *buf);

static struct clk *usb11_clk;
static struct phy *usb11_phy;
@@ -74,7 +88,7 @@ static void ohci_da8xx_ocic_handler(struct da8xx_ohci_root_hub *hub,
hub->set_power(port, 0);
}

-static int ohci_da8xx_init(struct usb_hcd *hcd)
+static int ohci_da8xx_reset(struct usb_hcd *hcd)
{
struct device *dev = hcd->self.controller;
struct da8xx_ohci_root_hub *hub = dev_get_platdata(dev);
@@ -94,7 +108,7 @@ static int ohci_da8xx_init(struct usb_hcd *hcd)
*/
ohci->num_ports = 1;

- result = ohci_init(ohci);
+ result = ohci_setup(hcd);
if (result < 0) {
ohci_da8xx_disable();
return result;
@@ -122,30 +136,12 @@ static int ohci_da8xx_init(struct usb_hcd *hcd)
return result;
}

-static void ohci_da8xx_stop(struct usb_hcd *hcd)
-{
- ohci_stop(hcd);
- ohci_da8xx_disable();
-}
-
-static int ohci_da8xx_start(struct usb_hcd *hcd)
-{
- struct ohci_hcd *ohci = hcd_to_ohci(hcd);
- int result;
-
- result = ohci_run(ohci);
- if (result < 0)
- ohci_da8xx_stop(hcd);
-
- return result;
-}
-
/*
* Update the status data from the hub with the over-current indicator change.
*/
static int ohci_da8xx_hub_status_data(struct usb_hcd *hcd, char *buf)
{
- int length = ohci_hub_status_data(hcd, buf);
+ int length = orig_ohci_hub_status_data(hcd, buf);

/* See if we have OCIC bit set on port 1 */
if (ocic_mask & (1 << 1)) {
@@ -227,66 +223,13 @@ static int ohci_da8xx_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
}
}

- return ohci_hub_control(hcd, typeReq, wValue, wIndex, buf, wLength);
+ return orig_ohci_hub_control(hcd, typeReq, wValue,
+ wIndex, buf, wLength);
}

-static const struct hc_driver ohci_da8xx_hc_driver = {
- .description = hcd_name,
- .product_desc = "DA8xx OHCI",
- .hcd_priv_size = sizeof(struct ohci_hcd),
-
- /*
- * generic hardware linkage
- */
- .irq = ohci_irq,
- .flags = HCD_USB11 | HCD_MEMORY,
-
- /*
- * basic lifecycle operations
- */
- .reset = ohci_da8xx_init,
- .start = ohci_da8xx_start,
- .stop = ohci_da8xx_stop,
- .shutdown = ohci_shutdown,
-
- /*
- * managing i/o requests and associated device resources
- */
- .urb_enqueue = ohci_urb_enqueue,
- .urb_dequeue = ohci_urb_dequeue,
- .endpoint_disable = ohci_endpoint_disable,
-
- /*
- * scheduling support
- */
- .get_frame_number = ohci_get_frame,
-
- /*
- * root hub support
- */
- .hub_status_data = ohci_da8xx_hub_status_data,
- .hub_control = ohci_da8xx_hub_control,
-
-#ifdef CONFIG_PM
- .bus_suspend = ohci_bus_suspend,
- .bus_resume = ohci_bus_resume,
-#endif
- .start_port_reset = ohci_start_port_reset,
-};
-
/*-------------------------------------------------------------------------*/

-
-/**
- * usb_hcd_da8xx_probe - initialize DA8xx-based HCDs
- * Context: !in_interrupt()
- *
- * Allocates basic resources for this USB host controller, and
- * then invokes the start() method for the HCD associated with it
- * through the hotplug entry's driver_data.
- */
-static int usb_hcd_da8xx_probe(const struct hc_driver *driver,
- struct platform_device *pdev)
+static int ohci_da8xx_probe(struct platform_device *pdev)
{
struct da8xx_ohci_root_hub *hub = dev_get_platdata(&pdev->dev);
struct usb_hcd *hcd;
@@ -310,7 +253,8 @@ static int usb_hcd_da8xx_probe(const struct hc_driver *driver,
return PTR_ERR(usb11_phy);
}

- hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
+ hcd = usb_create_hcd(&ohci_da8xx_hc_driver, &pdev->dev,
+ dev_name(&pdev->dev));
if (!hcd)
return -ENOMEM;

@@ -324,13 +268,12 @@ static int usb_hcd_da8xx_probe(const struct hc_driver *driver,
hcd->rsrc_start = mem->start;
hcd->rsrc_len = resource_size(mem);

- ohci_hcd_init(hcd_to_ohci(hcd));
-
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
error = -ENODEV;
goto err;
}
+
error = usb_add_hcd(hcd, irq, 0);
if (error)
goto err;
@@ -349,35 +292,14 @@ static int usb_hcd_da8xx_probe(const struct hc_driver *driver,
return error;
}

-/**
- * usb_hcd_da8xx_remove - shutdown processing for DA8xx-based HCDs
- * @dev: USB Host Controller being removed
- * Context: !in_interrupt()
- *
- * Reverses the effect of usb_hcd_da8xx_probe(), first invoking
- * the HCD's stop() method. It is always called from a thread
- * context, normally "rmmod", "apmd", or something similar.
- */
-static inline void
-usb_hcd_da8xx_remove(struct usb_hcd *hcd, struct platform_device *pdev)
+static int ohci_da8xx_remove(struct platform_device *pdev)
{
+ struct usb_hcd *hcd = platform_get_drvdata(pdev);
struct da8xx_ohci_root_hub *hub = dev_get_platdata(&pdev->dev);

hub->ocic_notify(NULL);
usb_remove_hcd(hcd);
usb_put_hcd(hcd);
-}
-
-static int ohci_hcd_da8xx_drv_probe(struct platform_device *dev)
-{
- return usb_hcd_da8xx_probe(&ohci_da8xx_hc_driver, dev);
-}
-
-static int ohci_hcd_da8xx_drv_remove(struct platform_device *dev)
-{
- struct usb_hcd *hcd = platform_get_drvdata(dev);
-
- usb_hcd_da8xx_remove(hcd, dev);

return 0;
}
@@ -427,20 +349,59 @@ static int ohci_da8xx_resume(struct platform_device *dev)
}
#endif

+static const struct ohci_driver_overrides da8xx_overrides __initconst = {
+ .reset = ohci_da8xx_reset,
+};
+
/*
* Driver definition to register with platform structure.
*/
static struct platform_driver ohci_hcd_da8xx_driver = {
- .probe = ohci_hcd_da8xx_drv_probe,
- .remove = ohci_hcd_da8xx_drv_remove,
+ .probe = ohci_da8xx_probe,
+ .remove = ohci_da8xx_remove,
.shutdown = usb_hcd_platform_shutdown,
#ifdef CONFIG_PM
.suspend = ohci_da8xx_suspend,
.resume = ohci_da8xx_resume,
#endif
.driver = {
- .name = "ohci",
+ .name = hcd_name,
},
};

+static int __init ohci_da8xx_init(void)
+{
+
+ if (usb_disabled())
+ return -ENODEV;
+
+ pr_info("%s: " DRIVER_DESC "\n", hcd_name);
+ ohci_init_driver(&ohci_da8xx_hc_driver, &da8xx_overrides);
+
+ /*
+ * The Davinci da8xx HW has some unusual quirks, which require
+ * da8xx-specific workarounds. We override certain hc_driver
+ * functions here to achieve that. We explicitly do not enhance
+ * ohci_driver_overrides to allow this more easily, since this
+ * is an unusual case, and we don't want to encourage others to
+ * override these functions by making it too easy.
+ */
+
+ orig_ohci_hub_control = ohci_da8xx_hc_driver.hub_control;
+ orig_ohci_hub_status_data = ohci_da8xx_hc_driver.hub_status_data;
+
+ ohci_da8xx_hc_driver.hub_status_data = ohci_da8xx_hub_status_data;
+ ohci_da8xx_hc_driver.hub_control = ohci_da8xx_hub_control;
+
+ return platform_driver_register(&ohci_hcd_da8xx_driver);
+}
+module_init(ohci_da8xx_init);
+
+static void __exit ohci_da8xx_exit(void)
+{
+ platform_driver_unregister(&ohci_hcd_da8xx_driver);
+}
+module_exit(ohci_da8xx_exit);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:ohci");
diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
index 86612ac..8685cf3 100644
--- a/drivers/usb/host/ohci-hcd.c
+++ b/drivers/usb/host/ohci-hcd.c
@@ -1219,11 +1219,6 @@ void ohci_init_driver(struct hc_driver *drv,
#define SA1111_DRIVER ohci_hcd_sa1111_driver
#endif

-#ifdef CONFIG_USB_OHCI_HCD_DAVINCI
-#include "ohci-da8xx.c"
-#define DAVINCI_PLATFORM_DRIVER ohci_hcd_da8xx_driver
-#endif
-
#ifdef CONFIG_USB_OHCI_HCD_PPC_OF
#include "ohci-ppc-of.c"
#define OF_PLATFORM_DRIVER ohci_hcd_ppc_of_driver
@@ -1303,19 +1298,9 @@ static int __init ohci_hcd_mod_init(void)
goto error_tmio;
#endif

-#ifdef DAVINCI_PLATFORM_DRIVER
- retval = platform_driver_register(&DAVINCI_PLATFORM_DRIVER);
- if (retval < 0)
- goto error_davinci;
-#endif
-
return retval;

/* Error path */
-#ifdef DAVINCI_PLATFORM_DRIVER
- platform_driver_unregister(&DAVINCI_PLATFORM_DRIVER);
- error_davinci:
-#endif
#ifdef TMIO_OHCI_DRIVER
platform_driver_unregister(&TMIO_OHCI_DRIVER);
error_tmio:
@@ -1351,9 +1336,6 @@ static int __init ohci_hcd_mod_init(void)

static void __exit ohci_hcd_mod_exit(void)
{
-#ifdef DAVINCI_PLATFORM_DRIVER
- platform_driver_unregister(&DAVINCI_PLATFORM_DRIVER);
-#endif
#ifdef TMIO_OHCI_DRIVER
platform_driver_unregister(&TMIO_OHCI_DRIVER);
#endif
--
1.9.1