ASoC: fsi: Add spin lock operation for accessing shared area

fsi_master_xxx function should be protected by spin lock,
because it are used from both FSI-A and FSI-B.

Signed-off-by: Kuninori Morimoto <morimoto.kuninori@renesas.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 26 insertions, 3 deletions

diff --git a/sound/soc/sh/fsi.c b/sound/soc/sh/fsi.c
index 5f9f2693f4eb..ebf358808db1 100644
--- a/sound/soc/sh/fsi.c
+++ b/sound/soc/sh/fsi.c
@@ -110,6 +110,7 @@ struct fsi_master {
         struct fsi_priv fsia;
         struct fsi_priv fsib;
         struct sh_fsi_platform_info *info;
+        spinlock_t lock;
 };
 
 /************************************************************************
@@ -168,30 +169,51 @@ static int fsi_reg_mask_set(struct fsi_priv *fsi, u32 reg, u32 mask, u32 data)
 
 static int fsi_master_write(struct fsi_master *master, u32 reg, u32 data)
 {
+        int ret;
+        unsigned long flags;
+
         if ((reg < MREG_START) ||
             (reg > MREG_END))
                 return -1;
 
-        return __fsi_reg_write((u32)(master->base + reg), data);
+        spin_lock_irqsave(&master->lock, flags);
+        ret = __fsi_reg_write((u32)(master->base + reg), data);
+        spin_unlock_irqrestore(&master->lock, flags);
+
+        return ret;
 }
 
 static u32 fsi_master_read(struct fsi_master *master, u32 reg)
 {
+        u32 ret;
+        unsigned long flags;
+
         if ((reg < MREG_START) ||
             (reg > MREG_END))
                 return 0;
 
-        return __fsi_reg_read((u32)(master->base + reg));
+        spin_lock_irqsave(&master->lock, flags);
+        ret = __fsi_reg_read((u32)(master->base + reg));
+        spin_unlock_irqrestore(&master->lock, flags);
+
+        return ret;
 }
 
 static int fsi_master_mask_set(struct fsi_master *master,
                                u32 reg, u32 mask, u32 data)
 {
+        int ret;
+        unsigned long flags;
+
         if ((reg < MREG_START) ||
             (reg > MREG_END))
                 return -1;
 
-        return __fsi_reg_mask_set((u32)(master->base + reg), mask, data);
+        spin_lock_irqsave(&master->lock, flags);
+        ret = __fsi_reg_mask_set((u32)(master->base + reg), mask, data);
+        spin_unlock_irqrestore(&master->lock, flags);
+
+        return ret;
 }
 
 /************************************************************************
@@ -929,6 +951,7 @@ static int fsi_probe(struct platform_device *pdev)
         master->fsia.master     = master;
         master->fsib.base       = master->base + 0x40;
         master->fsib.master     = master;
+        spin_lock_init(&master->lock);
 
         pm_runtime_enable(&pdev->dev);
         pm_runtime_resume(&pdev->dev);