From ca2c1dc04b3fe8846d691adecfd65978b7ed3008 Mon Sep 17 00:00:00 2001 From: Sylvain Rochet Date: Tue, 20 Jan 2015 14:38:59 +0100 Subject: USB: host: ehci-atmel: Add suspend/resume support 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 Acked-by: Boris Brezillon Acked-by: Alan Stern Acked-by: Nicolas Ferre Acked-by: Alexandre Belloni Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-atmel.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) (limited to 'drivers/usb/host/ehci-atmel.c') diff --git a/drivers/usb/host/ehci-atmel.c b/drivers/usb/host/ehci-atmel.c index 56a88506febe..5a15e3dd006b 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), }, }; -- cgit v1.2.3