usb: atmel_usba_udc: Rework at91sam9rl errata handling

at91sam9rl SoC has an erratum forcing us to toggle the BIAS on USB
suspend/resume events.

This specific handling is only activated when CONFIG_ARCH_AT91SAM9RL is
set and this option is only set when building a non-DT kernel, which is
problematic since non-DT support for at91sam9rl SoC has been removed.

Rework the toggle_bias implementation to attach it to the "at91sam9rl-udc"
compatible string.

Add new compatible strings to avoid executing at91sam9rl erratum handling
on other SoCs.

Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/Documentation/devicetree/bindings/usb/atmel-usb.txt b/Documentation/devicetree/bindings/usb/atmel-usb.txt
index bc2222ca3f2ad8bf0e1e173be5a63a5d09fc76a6..38fee0f66c1292db3323ea687c44483fbfa3feef 100644 (file)
--- a/Documentation/devicetree/bindings/usb/atmel-usb.txt
+++ b/Documentation/devicetree/bindings/usb/atmel-usb.txt
@@ -51,7 +51,10 @@ usb1: gadget@fffa4000 {
 Atmel High-Speed USB device controller
 
 Required properties:
- - compatible: Should be "atmel,at91sam9rl-udc"
+ - compatible: Should be one of the following
+              "at91sam9rl-udc"
+              "at91sam9g45-udc"
+              "sama5d3-udc"
  - reg: Address and length of the register set for the device
  - interrupts: Should contain usba interrupt
  - ep childnode: To specify the number of endpoints and their properties.

diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.c b/drivers/usb/gadget/udc/atmel_usba_udc.c
index ce882371786b184d7b02f4a451d6c8c1b7a80efa..36fd34b7738769cb298d41b5675220b8c9cb5f48 100644 (file)
--- a/drivers/usb/gadget/udc/atmel_usba_udc.c
+++ b/drivers/usb/gadget/udc/atmel_usba_udc.c
@@ -8,6 +8,7 @@
  * published by the Free Software Foundation.
  */
 #include <linux/clk.h>
+#include <linux/clk/at91_pmc.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
@@ -324,28 +325,12 @@ static int vbus_is_present(struct usba_udc *udc)
        return 1;
 }
 
-#if defined(CONFIG_ARCH_AT91SAM9RL)
-
-#include <linux/clk/at91_pmc.h>
-
-static void toggle_bias(int is_on)
-{
-       unsigned int uckr = at91_pmc_read(AT91_CKGR_UCKR);
-
-       if (is_on)
-               at91_pmc_write(AT91_CKGR_UCKR, uckr | AT91_PMC_BIASEN);
-       else
-               at91_pmc_write(AT91_CKGR_UCKR, uckr & ~(AT91_PMC_BIASEN));
-}
-
-#else
-
-static void toggle_bias(int is_on)
+static void toggle_bias(struct usba_udc *udc, int is_on)
 {
+       if (udc->errata && udc->errata->toggle_bias)
+               udc->errata->toggle_bias(udc, is_on);
 }
 
-#endif /* CONFIG_ARCH_AT91SAM9RL */
-
 static void next_fifo_transaction(struct usba_ep *ep, struct usba_request *req)
 {
        unsigned int transaction_len;
@@ -1620,7 +1605,7 @@ static irqreturn_t usba_udc_irq(int irq, void *devid)
        DBG(DBG_INT, "irq, status=%#08x\n", status);
 
        if (status & USBA_DET_SUSPEND) {
-               toggle_bias(0);
+               toggle_bias(udc, 0);
                usba_writel(udc, INT_CLR, USBA_DET_SUSPEND);
                DBG(DBG_BUS, "Suspend detected\n");
                if (udc->gadget.speed != USB_SPEED_UNKNOWN
@@ -1632,7 +1617,7 @@ static irqreturn_t usba_udc_irq(int irq, void *devid)
        }
 
        if (status & USBA_WAKE_UP) {
-               toggle_bias(1);
+               toggle_bias(udc, 1);
                usba_writel(udc, INT_CLR, USBA_WAKE_UP);
                DBG(DBG_BUS, "Wake Up CPU detected\n");
        }
@@ -1736,13 +1721,13 @@ static irqreturn_t usba_vbus_irq(int irq, void *devid)
        vbus = vbus_is_present(udc);
        if (vbus != udc->vbus_prev) {
                if (vbus) {
-                       toggle_bias(1);
+                       toggle_bias(udc, 1);
                        usba_writel(udc, CTRL, USBA_ENABLE_MASK);
                        usba_writel(udc, INT_ENB, USBA_END_OF_RESET);
                } else {
                        udc->gadget.speed = USB_SPEED_UNKNOWN;
                        reset_all_endpoints(udc);
-                       toggle_bias(0);
+                       toggle_bias(udc, 0);
                        usba_writel(udc, CTRL, USBA_DISABLE_MASK);
                        if (udc->driver->disconnect) {
                                spin_unlock(&udc->lock);
@@ -1788,7 +1773,7 @@ static int atmel_usba_start(struct usb_gadget *gadget,
        /* If Vbus is present, enable the controller and wait for reset */
        spin_lock_irqsave(&udc->lock, flags);
        if (vbus_is_present(udc) && udc->vbus_prev == 0) {
-               toggle_bias(1);
+               toggle_bias(udc, 1);
                usba_writel(udc, CTRL, USBA_ENABLE_MASK);
                usba_writel(udc, INT_ENB, USBA_END_OF_RESET);
        }
@@ -1811,7 +1796,7 @@ static int atmel_usba_stop(struct usb_gadget *gadget)
        spin_unlock_irqrestore(&udc->lock, flags);
 
        /* This will also disable the DP pullup */
-       toggle_bias(0);
+       toggle_bias(udc, 0);
        usba_writel(udc, CTRL, USBA_DISABLE_MASK);
 
        clk_disable_unprepare(udc->hclk);
@@ -1823,6 +1808,29 @@ static int atmel_usba_stop(struct usb_gadget *gadget)
 }
 
 #ifdef CONFIG_OF
+static void at91sam9rl_toggle_bias(struct usba_udc *udc, int is_on)
+{
+       unsigned int uckr = at91_pmc_read(AT91_CKGR_UCKR);
+
+       if (is_on)
+               at91_pmc_write(AT91_CKGR_UCKR, uckr | AT91_PMC_BIASEN);
+       else
+               at91_pmc_write(AT91_CKGR_UCKR, uckr & ~(AT91_PMC_BIASEN));
+}
+
+static const struct usba_udc_errata at91sam9rl_errata = {
+       .toggle_bias = at91sam9rl_toggle_bias,
+};
+
+static const struct of_device_id atmel_udc_dt_ids[] = {
+       { .compatible = "atmel,at91sam9rl-udc", .data = &at91sam9rl_errata },
+       { .compatible = "atmel,at91sam9g45-udc" },
+       { .compatible = "atmel,sama5d3-udc" },
+       { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, atmel_udc_dt_ids);
+
 static struct usba_ep * atmel_udc_of_init(struct platform_device *pdev,
                                                    struct usba_udc *udc)
 {
@@ -1830,10 +1838,17 @@ static struct usba_ep * atmel_udc_of_init(struct platform_device *pdev,
        const char *name;
        enum of_gpio_flags flags;
        struct device_node *np = pdev->dev.of_node;
+       const struct of_device_id *match;
        struct device_node *pp;
        int i, ret;
        struct usba_ep *eps, *ep;
 
+       match = of_match_node(atmel_udc_dt_ids, np);
+       if (!match)
+               return ERR_PTR(-EINVAL);
+
+       udc->errata = match->data;
+
        udc->num_ep = 0;
 
        udc->vbus_pin = of_get_named_gpio_flags(np, "atmel,vbus-gpio", 0,
@@ -2024,7 +2039,7 @@ static int usba_udc_probe(struct platform_device *pdev)
                dev_err(&pdev->dev, "Unable to enable pclk, aborting.\n");
                return ret;
        }
-       toggle_bias(0);
+
        usba_writel(udc, CTRL, USBA_DISABLE_MASK);
        clk_disable_unprepare(pclk);
 
@@ -2033,6 +2048,8 @@ static int usba_udc_probe(struct platform_device *pdev)
        else
                udc->usba_ep = usba_udc_pdata(pdev, udc);
 
+       toggle_bias(udc, 0);
+
        if (IS_ERR(udc->usba_ep))
                return PTR_ERR(udc->usba_ep);
 
@@ -2092,15 +2109,6 @@ static int __exit usba_udc_remove(struct platform_device *pdev)
        return 0;
 }
 
-#if defined(CONFIG_OF)
-static const struct of_device_id atmel_udc_dt_ids[] = {
-       { .compatible = "atmel,at91sam9rl-udc" },
-       { /* sentinel */ }
-};
-
-MODULE_DEVICE_TABLE(of, atmel_udc_dt_ids);
-#endif
-
 static struct platform_driver udc_driver = {
        .remove         = __exit_p(usba_udc_remove),
        .driver         = {

diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.h b/drivers/usb/gadget/udc/atmel_usba_udc.h
index a70706e8cb02e9eaeebd531bc7167bb48d9d9705..456899e9ee624d801887e97f5fda50ec6564ec90 100644 (file)
--- a/drivers/usb/gadget/udc/atmel_usba_udc.h
+++ b/drivers/usb/gadget/udc/atmel_usba_udc.h
@@ -304,6 +304,10 @@ struct usba_request {
        unsigned int                            mapped:1;
 };
 
+struct usba_udc_errata {
+       void (*toggle_bias)(struct usba_udc *udc, int is_on);
+};
+
 struct usba_udc {
        /* Protect hw registers from concurrent modifications */
        spinlock_t lock;
@@ -314,6 +318,7 @@ struct usba_udc {
        struct usb_gadget gadget;
        struct usb_gadget_driver *driver;
        struct platform_device *pdev;
+       const struct usba_udc_errata *errata;
        int irq;
        int vbus_pin;
        int vbus_pin_inverted;