staging: comedi: s626: define S626_LP_CNTR* registers based on channel number

Redefining the Counter Preload/Latch registers as a macro that calculates
the register offset based on the comedi channel number.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/s626.c

@@ -1334,7 +1334,7 @@ static const struct s626_enc_info s626_enc_chan_info[] = {
 		.set_load_trig		= s626_set_load_trig_a,
 		.set_mode		= s626_set_mode_a,
 		.reset_cap_flags	= s626_reset_cap_flags_a,
-		.my_latch_lsw		= S626_LP_CNTR0ALSW,
+		.my_latch_lsw		= S626_LP_CNTR(0),
 		.my_event_bits		= S626_EVBITS(0),
 	}, {
 		.chan			= 1,
@@ -1348,7 +1348,7 @@ static const struct s626_enc_info s626_enc_chan_info[] = {
 		.set_load_trig		= s626_set_load_trig_a,
 		.set_mode		= s626_set_mode_a,
 		.reset_cap_flags	= s626_reset_cap_flags_a,
-		.my_latch_lsw		= S626_LP_CNTR1ALSW,
+		.my_latch_lsw		= S626_LP_CNTR(1),
 		.my_event_bits		= S626_EVBITS(1),
 	}, {
 		.chan			= 2,
@@ -1362,7 +1362,7 @@ static const struct s626_enc_info s626_enc_chan_info[] = {
 		.set_load_trig		= s626_set_load_trig_a,
 		.set_mode		= s626_set_mode_a,
 		.reset_cap_flags	= s626_reset_cap_flags_a,
-		.my_latch_lsw		= S626_LP_CNTR2ALSW,
+		.my_latch_lsw		= S626_LP_CNTR(2),
 		.my_event_bits		= S626_EVBITS(2),
 	}, {
 		.chan			= 3,
@@ -1376,7 +1376,7 @@ static const struct s626_enc_info s626_enc_chan_info[] = {
 		.set_load_trig		= s626_set_load_trig_b,
 		.set_mode		= s626_set_mode_b,
 		.reset_cap_flags	= s626_reset_cap_flags_b,
-		.my_latch_lsw		= S626_LP_CNTR0BLSW,
+		.my_latch_lsw		= S626_LP_CNTR(3),
 		.my_event_bits		= S626_EVBITS(3),
 	}, {
 		.chan			= 4,
@@ -1390,7 +1390,7 @@ static const struct s626_enc_info s626_enc_chan_info[] = {
 		.set_load_trig		= s626_set_load_trig_b,
 		.set_mode		= s626_set_mode_b,
 		.reset_cap_flags	= s626_reset_cap_flags_b,
-		.my_latch_lsw		= S626_LP_CNTR1BLSW,
+		.my_latch_lsw		= S626_LP_CNTR(4),
 		.my_event_bits		= S626_EVBITS(4),
 	}, {
 		.chan			= 5,
@@ -1404,7 +1404,7 @@ static const struct s626_enc_info s626_enc_chan_info[] = {
 		.set_load_trig		= s626_set_load_trig_b,
 		.set_mode		= s626_set_mode_b,
 		.reset_cap_flags	= s626_reset_cap_flags_b,
-		.my_latch_lsw		= S626_LP_CNTR2BLSW,
+		.my_latch_lsw		= S626_LP_CNTR(5),
 		.my_event_bits		= S626_EVBITS(5),
 	},
 };

drivers/staging/comedi/drivers/s626.h

@@ -233,19 +233,9 @@
 #define S626_LP_CRA(x)		(0x0000 + (((x) % 3) * 0x4))
 #define S626_LP_CRB(x)		(0x0002 + (((x) % 3) * 0x4))
 
-/* Counter PreLoad (write) and Latch (read) Registers: */
-#define	S626_LP_CNTR0ALSW	0x000C	/* 0A lsw. */
-#define	S626_LP_CNTR0AMSW	0x000E	/* 0A msw. */
-#define	S626_LP_CNTR0BLSW	0x0010	/* 0B lsw. */
-#define	S626_LP_CNTR0BMSW	0x0012	/* 0B msw. */
-#define	S626_LP_CNTR1ALSW	0x0014	/* 1A lsw. */
-#define	S626_LP_CNTR1AMSW	0x0016	/* 1A msw. */
-#define	S626_LP_CNTR1BLSW	0x0018	/* 1B lsw. */
-#define	S626_LP_CNTR1BMSW	0x001A	/* 1B msw. */
-#define	S626_LP_CNTR2ALSW	0x001C	/* 2A lsw. */
-#define	S626_LP_CNTR2AMSW	0x001E	/* 2A msw. */
-#define	S626_LP_CNTR2BLSW	0x0020	/* 2B lsw. */
-#define	S626_LP_CNTR2BMSW	0x0022	/* 2B msw. */
+/* Counter PreLoad (write) and Latch (read) Registers: 0A 1A 2A 0B 1B 2B */
+#define S626_LP_CNTR(x)		(0x000c  + (((x) < 3) ? 0x0 : 0x4) + \
+					   (((x) % 3) * 0x8))
 
 /* Miscellaneous Registers (read/write): */
 #define S626_LP_MISC1		0x0088	/* Read/write Misc1. */