[PATCH] usb: gadget: at91_udc: move prepare clk into process context

[Ronald Wahl]

Commit 7628083227b6bc4a7e33d7c381d7a4e558424b6b added clock preparation in
interrupt context. This is not allowed as it might sleep. Move clock
preparation into process context (at91udc_probe).

Signed-off-by: Ronald Wahl <ronald.wahl at raritan.com>
---
 drivers/usb/gadget/at91_udc.c | 39 ++++++++++++++++++++++++++++++---------
 1 file changed, 30 insertions(+), 9 deletions(-)

diff --git a/drivers/usb/gadget/at91_udc.c b/drivers/usb/gadget/at91_udc.c
index cfd18bc..0b347a0 100644
--- a/drivers/usb/gadget/at91_udc.c
+++ b/drivers/usb/gadget/at91_udc.c
@@ -872,10 +872,10 @@ static void clk_on(struct at91_udc *udc)
 
 	if (IS_ENABLED(CONFIG_COMMON_CLK)) {
 		clk_set_rate(udc->uclk, 48000000);
-		clk_prepare_enable(udc->uclk);
+		clk_enable(udc->uclk);
 	}
-	clk_prepare_enable(udc->iclk);
-	clk_prepare_enable(udc->fclk);
+	clk_enable(udc->iclk);
+	clk_enable(udc->fclk);
 }
 
 static void clk_off(struct at91_udc *udc)
@@ -884,10 +884,10 @@ static void clk_off(struct at91_udc *udc)
 		return;
 	udc->clocked = 0;
 	udc->gadget.speed = USB_SPEED_UNKNOWN;
-	clk_disable_unprepare(udc->fclk);
-	clk_disable_unprepare(udc->iclk);
+	clk_disable(udc->fclk);
+	clk_disable(udc->iclk);
 	if (IS_ENABLED(CONFIG_COMMON_CLK))
-		clk_disable_unprepare(udc->uclk);
+		clk_disable(udc->uclk);
 }
 
 /*
@@ -1780,14 +1780,23 @@ static int at91udc_probe(struct platform_device *pdev)
 	}
 
 	/* don't do anything until we have both gadget driver and VBUS */
+	if (IS_ENABLED(CONFIG_COMMON_CLK)) {
+		retval = clk_prepare(udc->uclk);
+		if (retval)
+			goto fail1;
+	}
+	retval = clk_prepare(udc->fclk);
+	if (retval)
+		goto fail1a;
+
 	retval = clk_prepare_enable(udc->iclk);
 	if (retval)
-		goto fail1;
+		goto fail1b;
 	at91_udp_write(udc, AT91_UDP_TXVC, AT91_UDP_TXVC_TXVDIS);
 	at91_udp_write(udc, AT91_UDP_IDR, 0xffffffff);
 	/* Clear all pending interrupts - UDP may be used by bootloader. */
 	at91_udp_write(udc, AT91_UDP_ICR, 0xffffffff);
-	clk_disable_unprepare(udc->iclk);
+	clk_disable(udc->iclk);
 
 	/* request UDC and maybe VBUS irqs */
 	udc->udp_irq = platform_get_irq(pdev, 0);
@@ -1795,7 +1804,7 @@ static int at91udc_probe(struct platform_device *pdev)
 			0, driver_name, udc);
 	if (retval < 0) {
 		DBG("request irq %d failed\n", udc->udp_irq);
-		goto fail1;
+		goto fail1c;
 	}
 	if (gpio_is_valid(udc->board.vbus_pin)) {
 		retval = gpio_request(udc->board.vbus_pin, "udc_vbus");
@@ -1848,6 +1857,13 @@ fail3:
 		gpio_free(udc->board.vbus_pin);
 fail2:
 	free_irq(udc->udp_irq, udc);
+fail1c:
+	clk_unprepare(udc->iclk);
+fail1b:
+	clk_unprepare(udc->fclk);
+fail1a:
+	if (IS_ENABLED(CONFIG_COMMON_CLK))
+		clk_unprepare(udc->uclk);
 fail1:
 	if (IS_ENABLED(CONFIG_COMMON_CLK) && !IS_ERR(udc->uclk))
 		clk_put(udc->uclk);
@@ -1896,6 +1912,11 @@ static int __exit at91udc_remove(struct platform_device *pdev)
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	release_mem_region(res->start, resource_size(res));
 
+	if (IS_ENABLED(CONFIG_COMMON_CLK))
+		clk_unprepare(udc->uclk);
+	clk_unprepare(udc->fclk);
+	clk_unprepare(udc->iclk);
+
 	clk_put(udc->iclk);
 	clk_put(udc->fclk);
 	if (IS_ENABLED(CONFIG_COMMON_CLK))
-- 
1.9.3