From mboxrd@z Thu Jan 1 00:00:00 1970 From: ronald.wahl@raritan.com (Ronald Wahl) Date: Fri, 8 Aug 2014 11:42:42 +0200 Subject: [PATCH v4] usb: gadget: at91_udc: move prepare clk into process context Message-ID: <1407490962-16702-1-git-send-email-ronald.wahl@raritan.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Commit 7628083227b6bc4a7e33d7c381d7a4e558424b6b (usb: gadget: at91_udc: prepare clk before calling enable) added clock preparation in interrupt context. This is not allowed as it might sleep. Also setting the clock rate is unsafe to call from there for the same reason. Move clock preparation and setting clock rate into process context (at91udc_probe). Signed-off-by: Ronald Wahl --- v3 -> v4: - no code changes - update commit message - add changelog v2 -> v3: (NOTE: this patch was also send with the v2 tag) - moved setting the clock rate into process context as well as it may also sleep - update commit message v1 -> v2: - no changes (first v2 got out accidently) drivers/usb/gadget/udc/at91_udc.c | 44 ++++++++++++++++++++++++++++----------- 1 file changed, 32 insertions(+), 12 deletions(-) diff --git a/drivers/usb/gadget/udc/at91_udc.c b/drivers/usb/gadget/udc/at91_udc.c index cfd18bc..0d685d0 100644 --- a/drivers/usb/gadget/udc/at91_udc.c +++ b/drivers/usb/gadget/udc/at91_udc.c @@ -870,12 +870,10 @@ static void clk_on(struct at91_udc *udc) return; udc->clocked = 1; - if (IS_ENABLED(CONFIG_COMMON_CLK)) { - clk_set_rate(udc->uclk, 48000000); - clk_prepare_enable(udc->uclk); - } - clk_prepare_enable(udc->iclk); - clk_prepare_enable(udc->fclk); + if (IS_ENABLED(CONFIG_COMMON_CLK)) + clk_enable(udc->uclk); + clk_enable(udc->iclk); + clk_enable(udc->fclk); } static void clk_off(struct at91_udc *udc) @@ -884,10 +882,10 @@ 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 +1778,24 @@ 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)) { + clk_set_rate(udc->uclk, 48000000); + 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 +1803,7 @@ 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 +1856,13 @@ 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 +1911,11 @@ 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