From eb50702539f9be3765127d927d3e9ccfeb65f26e Mon Sep 17 00:00:00 2001 From: Robert Jarzmik Date: Sat, 24 Jan 2009 23:55:34 -0800 Subject: USB: pxa27x_udc: factor pullup code to prepare otg transceiver Prepare pxa27x_udc to handle usb D+ pullup properly : it should connect the pullup resistor and disconnect it only if no external transceiver is handling it. [ dbrownell@users.sourceforge.net: kerneldoc and gpio fixes ] Signed-off-by: Robert Jarzmik Signed-off-by: David Brownell Signed-off-by: Greg Kroah-Hartman diff --git a/drivers/usb/gadget/pxa27x_udc.c b/drivers/usb/gadget/pxa27x_udc.c index 990f40f..f814559 100644 --- a/drivers/usb/gadget/pxa27x_udc.c +++ b/drivers/usb/gadget/pxa27x_udc.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include @@ -1471,6 +1472,32 @@ static struct usb_ep_ops pxa_ep_ops = { .fifo_flush = pxa_ep_fifo_flush, }; +/** + * dplus_pullup - Connect or disconnect pullup resistor to D+ pin + * @udc: udc device + * @on: 0 if disconnect pullup resistor, 1 otherwise + * Context: any + * + * Handle D+ pullup resistor, make the device visible to the usb bus, and + * declare it as a full speed usb device + */ +static void dplus_pullup(struct pxa_udc *udc, int on) +{ + if (on) { + if (gpio_is_valid(udc->mach->gpio_pullup)) + gpio_set_value(udc->mach->gpio_pullup, + !udc->mach->gpio_pullup_inverted); + if (udc->mach->udc_command) + udc->mach->udc_command(PXA2XX_UDC_CMD_CONNECT); + } else { + if (gpio_is_valid(udc->mach->gpio_pullup)) + gpio_set_value(udc->mach->gpio_pullup, + udc->mach->gpio_pullup_inverted); + if (udc->mach->udc_command) + udc->mach->udc_command(PXA2XX_UDC_CMD_DISCONNECT); + } + udc->pullup_on = on; +} /** * pxa_udc_get_frame - Returns usb frame number @@ -1500,21 +1527,91 @@ static int pxa_udc_wakeup(struct usb_gadget *_gadget) return 0; } +static void udc_enable(struct pxa_udc *udc); +static void udc_disable(struct pxa_udc *udc); + +/** + * should_enable_udc - Tells if UDC should be enabled + * @udc: udc device + * Context: any + * + * The UDC should be enabled if : + * - the pullup resistor is connected + * - and a gadget driver is bound + * + * Returns 1 if UDC should be enabled, 0 otherwise + */ +static int should_enable_udc(struct pxa_udc *udc) +{ + int put_on; + + put_on = ((udc->pullup_on) && (udc->driver)); + return put_on; +} + +/** + * should_disable_udc - Tells if UDC should be disabled + * @udc: udc device + * Context: any + * + * The UDC should be disabled if : + * - the pullup resistor is not connected + * - or no gadget driver is bound + * + * Returns 1 if UDC should be disabled + */ +static int should_disable_udc(struct pxa_udc *udc) +{ + int put_off; + + put_off = ((!udc->pullup_on) || (!udc->driver)); + return put_off; +} + +/** + * pxa_udc_pullup - Offer manual D+ pullup control + * @_gadget: usb gadget using the control + * @is_active: 0 if disconnect, else connect D+ pullup resistor + * Context: !in_interrupt() + * + * Returns 0 if OK, -EOPNOTSUPP if udc driver doesn't handle D+ pullup + */ +static int pxa_udc_pullup(struct usb_gadget *_gadget, int is_active) +{ + struct pxa_udc *udc = to_gadget_udc(_gadget); + + if (!gpio_is_valid(udc->mach->gpio_pullup) && !udc->mach->udc_command) + return -EOPNOTSUPP; + + dplus_pullup(udc, is_active); + + if (should_enable_udc(udc)) + udc_enable(udc); + if (should_disable_udc(udc)) + udc_disable(udc); + return 0; +} + static const struct usb_gadget_ops pxa_udc_ops = { .get_frame = pxa_udc_get_frame, .wakeup = pxa_udc_wakeup, + .pullup = pxa_udc_pullup, /* current versions must always be self-powered */ }; /** * udc_disable - disable udc device controller * @udc: udc device + * Context: any * * Disables the udc device : disables clocks, udc interrupts, control endpoint * interrupts. */ static void udc_disable(struct pxa_udc *udc) { + if (!udc->enabled) + return; + udc_writel(udc, UDCICR0, 0); udc_writel(udc, UDCICR1, 0); @@ -1523,8 +1620,8 @@ static void udc_disable(struct pxa_udc *udc) ep0_idle(udc); udc->gadget.speed = USB_SPEED_UNKNOWN; - if (udc->mach->udc_command) - udc->mach->udc_command(PXA2XX_UDC_CMD_DISCONNECT); + + udc->enabled = 0; } /** @@ -1570,6 +1667,9 @@ static __init void udc_init_data(struct pxa_udc *dev) */ static void udc_enable(struct pxa_udc *udc) { + if (udc->enabled) + return; + udc_writel(udc, UDCICR0, 0); udc_writel(udc, UDCICR1, 0); udc_clear_mask_UDCCR(udc, UDCCR_UDE); @@ -1598,9 +1698,7 @@ static void udc_enable(struct pxa_udc *udc) /* enable ep0 irqs */ pio_irq_enable(&udc->pxa_ep[0]); - dev_info(udc->dev, "UDC connecting\n"); - if (udc->mach->udc_command) - udc->mach->udc_command(PXA2XX_UDC_CMD_CONNECT); + udc->enabled = 1; } /** @@ -1612,6 +1710,9 @@ static void udc_enable(struct pxa_udc *udc) * usb traffic follows until a disconnect is reported. Then a host may connect * again, or the driver might get unbound. * + * Note that the udc is not automatically enabled. Check function + * should_enable_udc(). + * * Returns 0 if no error, -EINVAL, -ENODEV, -EBUSY otherwise */ int usb_gadget_register_driver(struct usb_gadget_driver *driver) @@ -1630,6 +1731,7 @@ int usb_gadget_register_driver(struct usb_gadget_driver *driver) /* first hook up the driver ... */ udc->driver = driver; udc->gadget.dev.driver = &driver->driver; + dplus_pullup(udc, 1); retval = device_add(&udc->gadget.dev); if (retval) { @@ -1645,7 +1747,8 @@ int usb_gadget_register_driver(struct usb_gadget_driver *driver) dev_dbg(udc->dev, "registered gadget driver '%s'\n", driver->driver.name); - udc_enable(udc); + if (should_enable_udc(udc)) + udc_enable(udc); return 0; bind_fail: @@ -1699,6 +1802,7 @@ int usb_gadget_unregister_driver(struct usb_gadget_driver *driver) stop_activity(udc, driver); udc_disable(udc); + dplus_pullup(udc, 0); driver->unbind(&udc->gadget); udc->driver = NULL; @@ -2212,7 +2316,7 @@ static int __init pxa_udc_probe(struct platform_device *pdev) { struct resource *regs; struct pxa_udc *udc = &memory; - int retval; + int retval = 0, gpio; regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!regs) @@ -2224,6 +2328,19 @@ static int __init pxa_udc_probe(struct platform_device *pdev) udc->dev = &pdev->dev; udc->mach = pdev->dev.platform_data; + gpio = udc->mach->gpio_pullup; + if (gpio_is_valid(gpio)) { + retval = gpio_request(gpio, "USB D+ pullup"); + if (retval == 0) + gpio_direction_output(gpio, + udc->mach->gpio_pullup_inverted); + } + if (retval) { + dev_err(&pdev->dev, "Couldn't request gpio %d : %d\n", + gpio, retval); + return retval; + } + udc->clk = clk_get(&pdev->dev, NULL); if (IS_ERR(udc->clk)) { retval = PTR_ERR(udc->clk); @@ -2273,10 +2390,13 @@ err_clk: static int __exit pxa_udc_remove(struct platform_device *_dev) { struct pxa_udc *udc = platform_get_drvdata(_dev); + int gpio = udc->mach->gpio_pullup; usb_gadget_unregister_driver(udc->driver); free_irq(udc->irq, udc); pxa_cleanup_debugfs(udc); + if (gpio_is_valid(gpio)) + gpio_free(gpio); platform_set_drvdata(_dev, NULL); the_controller = NULL; @@ -2319,6 +2439,8 @@ static int pxa_udc_suspend(struct platform_device *_dev, pm_message_t state) } udc_disable(udc); + udc->pullup_resume = udc->pullup_on; + dplus_pullup(udc, 0); return 0; } @@ -2346,7 +2468,9 @@ static int pxa_udc_resume(struct platform_device *_dev) ep->udccsr_value, ep->udccr_value); } - udc_enable(udc); + dplus_pullup(udc, udc->pullup_resume); + if (should_enable_udc(udc)) + udc_enable(udc); /* * We do not handle OTG yet. * diff --git a/drivers/usb/gadget/pxa27x_udc.h b/drivers/usb/gadget/pxa27x_udc.h index 1d1b793..6f5234d 100644 --- a/drivers/usb/gadget/pxa27x_udc.h +++ b/drivers/usb/gadget/pxa27x_udc.h @@ -425,6 +425,9 @@ struct udc_stats { * @stats: statistics on udc usage * @udc_usb_ep: array of usb endpoints offered by the gadget * @pxa_ep: array of pxa available endpoints + * @enabled: UDC was enabled by a previous udc_enable() + * @pullup_on: if pullup resistor connected to D+ pin + * @pullup_resume: if pullup resistor should be connected to D+ pin on resume * @config: UDC active configuration * @last_interface: UDC interface of the last SET_INTERFACE host request * @last_alternate: UDC altsetting of the last SET_INTERFACE host request @@ -450,6 +453,9 @@ struct pxa_udc { struct udc_usb_ep udc_usb_ep[NR_USB_ENDPOINTS]; struct pxa_ep pxa_ep[NR_PXA_ENDPOINTS]; + unsigned enabled:1; + unsigned pullup_on:1; + unsigned pullup_resume:1; unsigned config:2; unsigned last_interface:3; unsigned last_alternate:3; -- cgit v0.10.2