ookkkay. I'm going to pretend that I had an email malfunction which
deleted all rmk and david-b email for the past 24 hours. I'd suggest that
others adopt the same pretence.
Russell, I have received the below from David. Could you please review it
for inclusion?
Thanks.
From: David Brownell <david-b@xxxxxxxxxxx>
This supports the clk_must_disable() interface for AT91 systems:
- Implement the call, replacing at91_suspend_entering_slow_clock();
- Use it in three drivers: USB Host, USB Peripheral, and RS232 serial.
Briefly, those are three of the drivers that need to act differently
when going into deeper sleep states (suspend-to-RAM), where among other
things they can't act as wakeup event sources.
(The at91_ethernet driver would be another such driver, but it doesn't
currently implement wake-on-LAN even in the "standby" mode.)
Signed-off-by: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/arm/mach-at91/clock.c | 18 ++++++++++++++++++
arch/arm/mach-at91/generic.h | 1 +
arch/arm/mach-at91/pm.c | 7 +------
drivers/serial/atmel_serial.c | 3 ++-
drivers/usb/gadget/at91_udc.c | 2 +-
drivers/usb/host/ohci-at91.c | 2 +-
6 files changed, 24 insertions(+), 9 deletions(-)
diff -puN arch/arm/mach-at91/clock.c~at91-implements-clk_must_disable arch/arm/mach-at91/clock.c
--- a/arch/arm/mach-at91/clock.c~at91-implements-clk_must_disable
+++ a/arch/arm/mach-at91/clock.c
@@ -32,6 +32,7 @@
#include <asm/arch/cpu.h>
#include "clock.h"
+#include "generic.h"
/*
@@ -254,6 +255,23 @@ EXPORT_SYMBOL(clk_get_rate);
/*------------------------------------------------------------------------*/
+#ifdef CONFIG_PM
+
+int clk_must_disable(struct clk *clk)
+{
+ if (!at91_suspend_entering_slow_clock())
+ return 0;
+
+ while (clk->parent)
+ clk = clk->parent;
+ return clk != &clk32k;
+}
+EXPORT_SYMBOL(clk_must_disable);
+
+#endif
+
+/*------------------------------------------------------------------------*/
+
#ifdef CONFIG_AT91_PROGRAMMABLE_CLOCKS
/*
diff -puN arch/arm/mach-at91/generic.h~at91-implements-clk_must_disable arch/arm/mach-at91/generic.h
--- a/arch/arm/mach-at91/generic.h~at91-implements-clk_must_disable
+++ a/arch/arm/mach-at91/generic.h
@@ -36,6 +36,7 @@ extern void __init at91_clock_associate(
/* Power Management */
extern void at91_irq_suspend(void);
extern void at91_irq_resume(void);
+extern int at91_suspend_entering_slow_clock(void);
/* GPIO */
#define AT91RM9200_PQFP 3 /* AT91RM9200 PQFP package has 3 banks */
diff -puN arch/arm/mach-at91/pm.c~at91-implements-clk_must_disable arch/arm/mach-at91/pm.c
--- a/arch/arm/mach-at91/pm.c~at91-implements-clk_must_disable
+++ a/arch/arm/mach-at91/pm.c
@@ -103,20 +103,15 @@ static int at91_pm_verify_clocks(void)
}
/*
- * Call this from platform driver suspend() to see how deeply to suspend.
+ * This is called from clk_must_disable(), to see how deeply to suspend.
* For example, some controllers (like OHCI) need one of the PLL clocks
* in order to act as a wakeup source, and those are not available when
* going into slow clock mode.
- *
- * REVISIT: generalize as clk_will_be_available(clk)? Other platforms have
- * the very same problem (but not using at91 main_clk), and it'd be better
- * to add one generic API rather than lots of platform-specific ones.
*/
int at91_suspend_entering_slow_clock(void)
{
return (target_state == PM_SUSPEND_MEM);
}
-EXPORT_SYMBOL(at91_suspend_entering_slow_clock);
static void (*slow_clock)(void);
diff -puN drivers/serial/atmel_serial.c~at91-implements-clk_must_disable drivers/serial/atmel_serial.c
--- a/drivers/serial/atmel_serial.c~at91-implements-clk_must_disable
+++ a/drivers/serial/atmel_serial.c
@@ -921,7 +921,8 @@ static int atmel_serial_suspend(struct p
struct uart_port *port = platform_get_drvdata(pdev);
struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
- if (device_may_wakeup(&pdev->dev) && !at91_suspend_entering_slow_clock())
+ if (device_may_wakeup(&pdev->dev)
+ && !clk_must_disable(atmel_port->clk))
enable_irq_wake(port->irq);
else {
uart_suspend_port(&atmel_uart, port);
diff -puN drivers/usb/gadget/at91_udc.c~at91-implements-clk_must_disable drivers/usb/gadget/at91_udc.c
--- a/drivers/usb/gadget/at91_udc.c~at91-implements-clk_must_disable
+++ a/drivers/usb/gadget/at91_udc.c
@@ -1782,7 +1782,7 @@ static int at91udc_suspend(struct platfo
*/
if ((!udc->suspended && udc->addr)
|| !wake
- || at91_suspend_entering_slow_clock()) {
+ || clk_must_disable(udc->fclk)) {
pullup(udc, 0);
wake = 0;
} else
diff -puN drivers/usb/host/ohci-at91.c~at91-implements-clk_must_disable drivers/usb/host/ohci-at91.c
--- a/drivers/usb/host/ohci-at91.c~at91-implements-clk_must_disable
+++ a/drivers/usb/host/ohci-at91.c
@@ -299,7 +299,7 @@ ohci_hcd_at91_drv_suspend(struct platfor
*
* REVISIT: some boards will be able to turn VBUS off...
*/
- if (at91_suspend_entering_slow_clock()) {
+ if (clk_must_disable(fclk)) {
ohci_usb_reset (ohci);
at91_stop_clock();
}
_
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