From mboxrd@z Thu Jan 1 00:00:00 1970 From: sylvain.rochet@finsecur.com (Sylvain Rochet) Date: Sat, 17 Jan 2015 16:36:34 +0100 Subject: [PATCHv2 1/2] USB: host: ehci_atmel: Add suspend/resume support In-Reply-To: <20150117135857.71dae08f@bbrezillon> References: <20150117135857.71dae08f@bbrezillon> Message-ID: <1421508995-21290-1-git-send-email-sylvain.rochet@finsecur.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org This patch add suspend/resume support for Atmel EHCI, mostly about disabling and unpreparing clocks so USB PLL is stopped before entering sleep state. Signed-off-by: Sylvain Rochet --- drivers/usb/host/ehci-atmel.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/drivers/usb/host/ehci-atmel.c b/drivers/usb/host/ehci-atmel.c index 56a8850..2e0043b 100644 --- a/drivers/usb/host/ehci-atmel.c +++ b/drivers/usb/host/ehci-atmel.c @@ -37,6 +37,8 @@ static int clocked; static void atmel_start_clock(void) { + if (clocked) + return; if (IS_ENABLED(CONFIG_COMMON_CLK)) { clk_set_rate(uclk, 48000000); clk_prepare_enable(uclk); @@ -48,6 +50,8 @@ static void atmel_start_clock(void) static void atmel_stop_clock(void) { + if (!clocked) + return; clk_disable_unprepare(fclk); clk_disable_unprepare(iclk); if (IS_ENABLED(CONFIG_COMMON_CLK)) @@ -174,6 +178,32 @@ static int ehci_atmel_drv_remove(struct platform_device *pdev) return 0; } +#ifdef CONFIG_PM +static int ehci_atmel_drv_suspend(struct platform_device *pdev, pm_message_t mesg) +{ + struct usb_hcd *hcd = platform_get_drvdata(pdev); + int ret; + + ret = ehci_suspend(hcd, false); + if (ret) + return ret; + + atmel_stop_clock(); + return 0; +} + +static int ehci_atmel_drv_resume(struct platform_device *pdev) +{ + struct usb_hcd *hcd = platform_get_drvdata(pdev); + + atmel_start_clock(); + return ehci_resume(hcd, false); +} +#else +#define ehci_atmel_drv_suspend NULL +#define ehci_atmel_drv_resume NULL +#endif + #ifdef CONFIG_OF static const struct of_device_id atmel_ehci_dt_ids[] = { { .compatible = "atmel,at91sam9g45-ehci" }, @@ -187,6 +217,8 @@ static struct platform_driver ehci_atmel_driver = { .probe = ehci_atmel_drv_probe, .remove = ehci_atmel_drv_remove, .shutdown = usb_hcd_platform_shutdown, + .suspend = ehci_atmel_drv_suspend, + .resume = ehci_atmel_drv_resume, .driver = { .name = "atmel-ehci", .of_match_table = of_match_ptr(atmel_ehci_dt_ids), -- 2.1.4