[PATCH v3 4/4] soc: ti: pm33xx: Save/restore clk context based on enable_off_mode setting

[Keerthy]

Save/restore clk context based on enable_off_mode setting.
The context needs to be saved at the very end of suspend path
and restored at the beginning of resume path.

Signed-off-by: Keerthy <j-keer...@ti.com>
---

No Changes in v2

 arch/arm/mach-omap2/pm33xx-core.c    | 15 +++++++++++++++
 drivers/soc/ti/pm33xx.c              | 13 +++++++++++++
 include/linux/platform_data/pm33xx.h |  1 +
 3 files changed, 29 insertions(+)

diff --git a/arch/arm/mach-omap2/pm33xx-core.c 
b/arch/arm/mach-omap2/pm33xx-core.c
index 9b3755a..29f848f 100644
--- a/arch/arm/mach-omap2/pm33xx-core.c
+++ b/arch/arm/mach-omap2/pm33xx-core.c
@@ -37,6 +37,20 @@ static int __init am43xx_map_scu(void)
        return 0;
 }
 
+static int am43xx_check_off_mode_enable(void)
+{
+       /*
+        * Check for am437x-sk-evm which due to HW design cannot support
+        * this mode reliably.
+        */
+       if (of_machine_is_compatible("ti,am437x-sk-evm") && enable_off_mode) {
+               pr_warn("WARNING: This platform does not support off-mode, 
entering DeepSleep suspend.\n");
+               return 0;
+       }
+
+       return enable_off_mode;
+}
+
 static int amx3_common_init(void)
 {
        gfx_pwrdm = pwrdm_lookup("gfx_pwrdm");
@@ -161,6 +175,7 @@ static struct am33xx_pm_sram_addr *amx3_get_sram_addrs(void)
        .init = am43xx_suspend_init,
        .soc_suspend = am43xx_suspend,
        .get_sram_addrs = amx3_get_sram_addrs,
+       .check_off_mode_enable = am43xx_check_off_mode_enable,
 };
 
 static struct am33xx_pm_platform_data *am33xx_pm_get_pdata(void)
diff --git a/drivers/soc/ti/pm33xx.c b/drivers/soc/ti/pm33xx.c
index 652739c..e749b8d 100644
--- a/drivers/soc/ti/pm33xx.c
+++ b/drivers/soc/ti/pm33xx.c
@@ -6,6 +6,7 @@
  *     Vaibhav Bedia, Dave Gerlach
  */
 
+#include <linux/clk.h>
 #include <linux/cpu.h>
 #include <linux/err.h>
 #include <linux/genalloc.h>
@@ -52,6 +53,14 @@ static int am33xx_pm_suspend(suspend_state_t suspend_state)
 {
        int i, ret = 0;
 
+       /*
+        * For RTC only mode with DDR in selfresh we need to save
+        * clocks context at the very end
+        */
+       if (suspend_state == PM_SUSPEND_MEM &&
+           pm_ops->check_off_mode_enable())
+               clk_save_context();
+
        ret = pm_ops->soc_suspend((unsigned long)suspend_state,
                                  am33xx_do_wfi_sram);
 
@@ -77,6 +86,10 @@ static int am33xx_pm_suspend(suspend_state_t suspend_state)
                }
        }
 
+       if (suspend_state == PM_SUSPEND_MEM &&
+           pm_ops->check_off_mode_enable())
+               clk_restore_context();
+
        return ret;
 }
 
diff --git a/include/linux/platform_data/pm33xx.h 
b/include/linux/platform_data/pm33xx.h
index f9bed2a..36f7007 100644
--- a/include/linux/platform_data/pm33xx.h
+++ b/include/linux/platform_data/pm33xx.h
@@ -25,6 +25,7 @@ struct am33xx_pm_platform_data {
        int     (*init)(void);
        int     (*soc_suspend)(unsigned int state, int (*fn)(unsigned long));
        struct  am33xx_pm_sram_addr *(*get_sram_addrs)(void);
+       int (*check_off_mode_enable)(void);
 };
 
 struct am33xx_pm_sram_data {
-- 
1.9.1