USB: pxa2xx_udc understands GPIO based VBUS sensing

This updates the PXA 25x UDC board-independent infrastructure for VBUS sensing
and the D+ pullup.  The original code evolved from rather bizarre support on
Intel's "Lubbock" reference hardware, so that on more sensible hardware it
doesn't work as well as it could/should.

The change is just to teach the UDC driver how to use built-in PXA GPIO pins
directly.  This reduces the amount of board-specfic object code needed, and
enables the use of a VBUS sensing IRQ on boards (like Gumstix) that have one.
With VBUS sensing, the UDC is unclocked until a host is actually connected.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/arch/arm/mach-pxa/corgi.c b/arch/arm/mach-pxa/corgi.c
index cce2657..337c01c 100644 (file)
--- a/arch/arm/mach-pxa/corgi.c
+++ b/arch/arm/mach-pxa/corgi.c
@@ -284,21 +284,9 @@ static struct pxaficp_platform_data corgi_ficp_platform_data = {
 /*
  * USB Device Controller
  */
-static void corgi_udc_command(int cmd)
-{
-       switch(cmd)     {
-       case PXA2XX_UDC_CMD_CONNECT:
-               GPSR(CORGI_GPIO_USB_PULLUP) = GPIO_bit(CORGI_GPIO_USB_PULLUP);
-               break;
-       case PXA2XX_UDC_CMD_DISCONNECT:
-               GPCR(CORGI_GPIO_USB_PULLUP) = GPIO_bit(CORGI_GPIO_USB_PULLUP);
-               break;
-       }
-}
-
 static struct pxa2xx_udc_mach_info udc_info __initdata = {
        /* no connect GPIO; corgi can't tell connection status */
-       .udc_command            = corgi_udc_command,
+       .gpio_pullup            = CORGI_GPIO_USB_PULLUP,
 };
 
 
@@ -350,7 +338,6 @@ static void __init corgi_init(void)
        corgi_ssp_set_machinfo(&corgi_ssp_machinfo);
 
        pxa_gpio_mode(CORGI_GPIO_IR_ON | GPIO_OUT);
-       pxa_gpio_mode(CORGI_GPIO_USB_PULLUP | GPIO_OUT);
        pxa_gpio_mode(CORGI_GPIO_HSYNC | GPIO_IN);
 
        pxa_set_udc_info(&udc_info);

diff --git a/drivers/usb/gadget/pxa2xx_udc.c b/drivers/usb/gadget/pxa2xx_udc.c
index fff027d..f1adcf8 100644 (file)
--- a/drivers/usb/gadget/pxa2xx_udc.c
+++ b/drivers/usb/gadget/pxa2xx_udc.c
@@ -150,6 +150,39 @@ MODULE_PARM_DESC (fifo_mode, "pxa2xx udc fifo mode");
 static void pxa2xx_ep_fifo_flush (struct usb_ep *ep);
 static void nuke (struct pxa2xx_ep *, int status);
 
+/* one GPIO should be used to detect VBUS from the host */
+static int is_vbus_present(void)
+{
+       struct pxa2xx_udc_mach_info             *mach = the_controller->mach;
+
+       if (mach->gpio_vbus)
+               return pxa_gpio_get(mach->gpio_vbus);
+       if (mach->udc_is_connected)
+               return mach->udc_is_connected();
+       return 1;
+}
+
+/* one GPIO should control a D+ pullup, so host sees this device (or not) */
+static void pullup_off(void)
+{
+       struct pxa2xx_udc_mach_info             *mach = the_controller->mach;
+
+       if (mach->gpio_pullup)
+               pxa_gpio_set(mach->gpio_pullup, 0);
+       else if (mach->udc_command)
+               mach->udc_command(PXA2XX_UDC_CMD_DISCONNECT);
+}
+
+static void pullup_on(void)
+{
+       struct pxa2xx_udc_mach_info             *mach = the_controller->mach;
+
+       if (mach->gpio_pullup)
+               pxa_gpio_set(mach->gpio_pullup, 1);
+       else if (mach->udc_command)
+               mach->udc_command(PXA2XX_UDC_CMD_CONNECT);
+}
+
 static void pio_irq_enable(int bEndpointAddress)
 {
         bEndpointAddress &= 0xf;
@@ -1721,6 +1754,16 @@ lubbock_vbus_irq(int irq, void *_dev, struct pt_regs *r)
 
 #endif
 
+static irqreturn_t
+udc_vbus_irq(int irq, void *_dev, struct pt_regs *r)
+{
+       struct pxa2xx_udc       *dev = _dev;
+       int                     vbus = pxa_gpio_get(dev->mach->gpio_vbus);
+
+       pxa2xx_udc_vbus_session(&dev->gadget, vbus);
+       return IRQ_HANDLED;
+}
+
 
 /*-------------------------------------------------------------------------*/
 
@@ -2438,7 +2481,7 @@ static struct pxa2xx_udc memory = {
 static int __init pxa2xx_udc_probe(struct platform_device *pdev)
 {
        struct pxa2xx_udc *dev = &memory;
-       int retval, out_dma = 1;
+       int retval, out_dma = 1, vbus_irq;
        u32 chiprev;
 
        /* insist on Intel/ARM/XScale */
@@ -2502,6 +2545,16 @@ static int __init pxa2xx_udc_probe(struct platform_device *pdev)
        /* other non-static parts of init */
        dev->dev = &pdev->dev;
        dev->mach = pdev->dev.platform_data;
+       if (dev->mach->gpio_vbus) {
+               vbus_irq = IRQ_GPIO(dev->mach->gpio_vbus & GPIO_MD_MASK_NR);
+               pxa_gpio_mode((dev->mach->gpio_vbus & GPIO_MD_MASK_NR)
+                               | GPIO_IN);
+               set_irq_type(vbus_irq, IRQT_BOTHEDGE);
+       } else
+               vbus_irq = 0;
+       if (dev->mach->gpio_pullup)
+               pxa_gpio_mode((dev->mach->gpio_pullup & GPIO_MD_MASK_NR)
+                               | GPIO_OUT | GPIO_DFLT_LOW);
 
        init_timer(&dev->timer);
        dev->timer.function = udc_watchdog;
@@ -2557,8 +2610,19 @@ lubbock_fail0:
                HEX_DISPLAY(dev->stats.irqs);
                LUB_DISC_BLNK_LED &= 0xff;
 #endif
-       }
+       } else
 #endif
+       if (vbus_irq) {
+               retval = request_irq(vbus_irq, udc_vbus_irq,
+                               SA_INTERRUPT | SA_SAMPLE_RANDOM,
+                               driver_name, dev);
+               if (retval != 0) {
+                       printk(KERN_ERR "%s: can't get irq %i, err %d\n",
+                               driver_name, vbus_irq, retval);
+                       free_irq(IRQ_USB, dev);
+                       return -EBUSY;
+               }
+       }
        create_proc_files();
 
        return 0;
@@ -2587,6 +2651,8 @@ static int __exit pxa2xx_udc_remove(struct platform_device *pdev)
                free_irq(LUBBOCK_USB_IRQ, dev);
        }
 #endif
+       if (dev->mach->gpio_vbus)
+               free_irq(IRQ_GPIO(dev->mach->gpio_vbus), dev);
        platform_set_drvdata(pdev, NULL);
        the_controller = NULL;
        return 0;

diff --git a/drivers/usb/gadget/pxa2xx_udc.h b/drivers/usb/gadget/pxa2xx_udc.h
index 19a883f..8e598c8 100644 (file)
--- a/drivers/usb/gadget/pxa2xx_udc.h
+++ b/drivers/usb/gadget/pxa2xx_udc.h
@@ -177,27 +177,19 @@ struct pxa2xx_udc {
 
 static struct pxa2xx_udc *the_controller;
 
-/* one GPIO should be used to detect VBUS from the host */
-static inline int is_vbus_present(void)
+static inline int pxa_gpio_get(unsigned gpio)
 {
-       if (!the_controller->mach->udc_is_connected)
-               return 1;
-       return the_controller->mach->udc_is_connected();
+       return (GPLR(gpio) & GPIO_bit(gpio)) != 0;
 }
 
-/* one GPIO should control a D+ pullup, so host sees this device (or not) */
-static inline void pullup_off(void)
+static inline void pxa_gpio_set(unsigned gpio, int is_on)
 {
-       if (!the_controller->mach->udc_command)
-               return;
-       the_controller->mach->udc_command(PXA2XX_UDC_CMD_DISCONNECT);
-}
+       int mask = GPIO_bit(gpio);
 
-static inline void pullup_on(void)
-{
-       if (!the_controller->mach->udc_command)
-               return;
-       the_controller->mach->udc_command(PXA2XX_UDC_CMD_CONNECT);
+       if (is_on)
+               GPSR(gpio) = mask;
+       else
+               GPCR(gpio) = mask;
 }
 
 /*-------------------------------------------------------------------------*/

diff --git a/include/asm-arm/arch-pxa/udc.h b/include/asm-arm/arch-pxa/udc.h
index 30548a3..121cd24 100644 (file)
--- a/include/asm-arm/arch-pxa/udc.h
+++ b/include/asm-arm/arch-pxa/udc.h
@@ -12,6 +12,14 @@ struct pxa2xx_udc_mach_info {
         void (*udc_command)(int cmd);
 #define        PXA2XX_UDC_CMD_CONNECT          0       /* let host see us */
 #define        PXA2XX_UDC_CMD_DISCONNECT       1       /* so host won't see us */
+
+       /* Boards following the design guidelines in the developer's manual,
+        * with on-chip GPIOs not Lubbock's wierd hardware, can have a sane
+        * VBUS IRQ and omit the methods above.  Store the GPIO number
+        * here; for GPIO 0, also mask in one of the pxa_gpio_mode() bits.
+        */
+       u16     gpio_vbus;                      /* high == vbus present */
+       u16     gpio_pullup;                    /* high == pullup activated */
 };
 
 extern void pxa_set_udc_info(struct pxa2xx_udc_mach_info *info);