[alsa-devel] [PATCH 4/4] ASoC: sh: fsi: remove runtime register check from fsi_master_xxx

[Kuninori Morimoto]

Current FSI driver was checking register range on fsi_master_xxx function.
This runtime check was added to avoid an illegal access
from wrong/mistake implementation.
But it is useless check under the correct implementation.
This patch escape runtime check by using macro technique.
If there is wrong implementation, it will be compile error.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
---
 sound/soc/sh/fsi.c |   48 ++++++++++++++++++++----------------------------
 1 files changed, 20 insertions(+), 28 deletions(-)

diff --git a/sound/soc/sh/fsi.c b/sound/soc/sh/fsi.c
index 66abb6e..19a2f99 100644
--- a/sound/soc/sh/fsi.c
+++ b/sound/soc/sh/fsi.c
@@ -33,6 +33,12 @@
 #define REG_MUTE_ST	0x0028
 #define REG_OUT_SEL	0x0030
 
+/* master register */
+#define MST_CLK_RST	0x0210
+#define MST_SOFT_RST	0x0214
+#define MST_FIFO_SZ	0x0218
+
+/* core register (depend on FSI version) */
 #define A_MST_CTLR	0x0180
 #define B_MST_CTLR	0x01A0
 #define CPU_INT_ST	0x01F4
@@ -41,12 +47,6 @@
 #define INT_ST		0x0200
 #define IEMSK		0x0204
 #define IMSK		0x0208
-#define MUTE		0x020C
-#define CLK_RST		0x0210
-#define SOFT_RST	0x0214
-#define FIFO_SZ		0x0218
-#define MREG_START	A_MST_CTLR
-#define MREG_END	FIFO_SZ
 
 /* DO_FMT */
 /* DI_FMT */
@@ -200,17 +200,13 @@ static void __fsi_reg_mask_set(u32 reg, u32 mask, u32 data)
 #define fsi_reg_mask_set(p, r, m, d)\
 	__fsi_reg_mask_set((u32)(p->base + REG_##r), m, d)
 
-static u32 fsi_master_read(struct fsi_master *master, u32 reg)
+#define fsi_master_read(p, r) _fsi_master_read(p, MST_##r)
+#define fsi_core_read(p, r)   _fsi_master_read(p, p->core->r)
+static u32 _fsi_master_read(struct fsi_master *master, u32 reg)
 {
 	u32 ret;
 	unsigned long flags;
 
-	if ((reg < MREG_START) ||
-	    (reg > MREG_END)) {
-		pr_err("fsi: register access err (%s)\n", __func__);
-		return 0;
-	}
-
 	spin_lock_irqsave(&master->lock, flags);
 	ret = __fsi_reg_read((u32)(master->base + reg));
 	spin_unlock_irqrestore(&master->lock, flags);
@@ -218,17 +214,13 @@ static u32 fsi_master_read(struct fsi_master *master, u32 reg)
 	return ret;
 }
 
-static void fsi_master_mask_set(struct fsi_master *master,
+#define fsi_master_mask_set(p, r, m, d) _fsi_master_mask_set(p, MST_##r, m, d)
+#define fsi_core_mask_set(p, r, m, d)  _fsi_master_mask_set(p, p->core->r, m, d)
+static void _fsi_master_mask_set(struct fsi_master *master,
 			       u32 reg, u32 mask, u32 data)
 {
 	unsigned long flags;
 
-	if ((reg < MREG_START) ||
-	    (reg > MREG_END)) {
-		pr_err("fsi: register access err (%s)\n", __func__);
-		return;
-	}
-
 	spin_lock_irqsave(&master->lock, flags);
 	__fsi_reg_mask_set((u32)(master->base + reg), mask, data);
 	spin_unlock_irqrestore(&master->lock, flags);
@@ -448,8 +440,8 @@ static void fsi_irq_enable(struct fsi_priv *fsi, int is_play)
 	u32 data = AB_IO(1, fsi_get_port_shift(fsi, is_play));
 	struct fsi_master *master = fsi_get_master(fsi);
 
-	fsi_master_mask_set(master, master->core->imsk,  data, data);
-	fsi_master_mask_set(master, master->core->iemsk, data, data);
+	fsi_core_mask_set(master, imsk,  data, data);
+	fsi_core_mask_set(master, iemsk, data, data);
 }
 
 static void fsi_irq_disable(struct fsi_priv *fsi, int is_play)
@@ -457,13 +449,13 @@ static void fsi_irq_disable(struct fsi_priv *fsi, int is_play)
 	u32 data = AB_IO(1, fsi_get_port_shift(fsi, is_play));
 	struct fsi_master *master = fsi_get_master(fsi);
 
-	fsi_master_mask_set(master, master->core->imsk,  data, 0);
-	fsi_master_mask_set(master, master->core->iemsk, data, 0);
+	fsi_core_mask_set(master, imsk,  data, 0);
+	fsi_core_mask_set(master, iemsk, data, 0);
 }
 
 static u32 fsi_irq_get_status(struct fsi_master *master)
 {
-	return fsi_master_read(master, master->core->int_st);
+	return fsi_core_read(master, int_st);
 }
 
 static void fsi_irq_clear_status(struct fsi_priv *fsi)
@@ -475,7 +467,7 @@ static void fsi_irq_clear_status(struct fsi_priv *fsi)
 	data |= AB_IO(1, fsi_get_port_shift(fsi, 1));
 
 	/* clear interrupt factor */
-	fsi_master_mask_set(master, master->core->int_st, data, 0);
+	fsi_core_mask_set(master, int_st, data, 0);
 }
 
 /*
@@ -497,8 +489,8 @@ static void fsi_spdif_clk_ctrl(struct fsi_priv *fsi, int enable)
 	val = enable ? mask : 0;
 
 	fsi_is_port_a(fsi) ?
-		fsi_master_mask_set(master, master->core->a_mclk, mask, val) :
-		fsi_master_mask_set(master, master->core->b_mclk, mask, val);
+		fsi_core_mask_set(master, a_mclk, mask, val) :
+		fsi_core_mask_set(master, b_mclk, mask, val);
 }
 
 /*
-- 
1.7.1