From mboxrd@z Thu Jan 1 00:00:00 1970 From: sylvain.rochet@finsecur.com (Sylvain Rochet) Date: Sun, 18 Jan 2015 20:36:01 +0100 Subject: [PATCHv4 1/6] USB: host: ehci-atmel: Add suspend/resume support In-Reply-To: <1421609766-11204-1-git-send-email-sylvain.rochet@finsecur.com> References: <1421609766-11204-1-git-send-email-sylvain.rochet@finsecur.com> Message-ID: <1421609766-11204-2-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 | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/usb/host/ehci-atmel.c b/drivers/usb/host/ehci-atmel.c index 56a8850..5a15e3d 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 +178,29 @@ static int ehci_atmel_drv_remove(struct platform_device *pdev) return 0; } +#ifdef CONFIG_PM +static int ehci_atmel_drv_suspend(struct device *dev) +{ + struct usb_hcd *hcd = dev_get_drvdata(dev); + int ret; + + ret = ehci_suspend(hcd, false); + if (ret) + return ret; + + atmel_stop_clock(); + return 0; +} + +static int ehci_atmel_drv_resume(struct device *dev) +{ + struct usb_hcd *hcd = dev_get_drvdata(dev); + + atmel_start_clock(); + return ehci_resume(hcd, false); +} +#endif + #ifdef CONFIG_OF static const struct of_device_id atmel_ehci_dt_ids[] = { { .compatible = "atmel,at91sam9g45-ehci" }, @@ -183,12 +210,16 @@ static const struct of_device_id atmel_ehci_dt_ids[] = { MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids); #endif +static SIMPLE_DEV_PM_OPS(ehci_atmel_pm_ops, ehci_atmel_drv_suspend, + ehci_atmel_drv_resume); + static struct platform_driver ehci_atmel_driver = { .probe = ehci_atmel_drv_probe, .remove = ehci_atmel_drv_remove, .shutdown = usb_hcd_platform_shutdown, .driver = { .name = "atmel-ehci", + .pm = &ehci_atmel_pm_ops, .of_match_table = of_match_ptr(atmel_ehci_dt_ids), }, }; -- 2.1.4