Re: [PATCH 6/8 v2] staging: pi433: use defines for shifting register values

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 





Am 13.12.2017 um 18:55 schrieb Valentin Vidic:
Avoid shifting by magic numbers and use defines instead.

Signed-off-by: Valentin Vidic <Valentin.Vidic@xxxxxxxxx>
---
v2: - drop change for SHIFT_DATAMODUL_MODULATION_TYPE
     - move shifting to the header file

  drivers/staging/pi433/rf69.c           | 16 ++++++++--------
  drivers/staging/pi433/rf69_registers.h |  8 ++++++++
  2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/drivers/staging/pi433/rf69.c b/drivers/staging/pi433/rf69.c
index f77ecd60f43a..ce259b4f0b0e 100644
--- a/drivers/staging/pi433/rf69.c
+++ b/drivers/staging/pi433/rf69.c
@@ -340,14 +340,14 @@ enum lnaGain rf69_get_lna_gain(struct spi_device *spi)
currentValue = rf69_read_reg(spi, REG_LNA); - switch (currentValue & MASK_LNA_CURRENT_GAIN >> 3) { // improvement: change 3 to define
-	case LNA_GAIN_AUTO:	    return automatic;
-	case LNA_GAIN_MAX:	    return max;
-	case LNA_GAIN_MAX_MINUS_6:  return maxMinus6;
-	case LNA_GAIN_MAX_MINUS_12: return maxMinus12;
-	case LNA_GAIN_MAX_MINUS_24: return maxMinus24;
-	case LNA_GAIN_MAX_MINUS_36: return maxMinus36;
-	case LNA_GAIN_MAX_MINUS_48: return maxMinus48;
+	switch (currentValue & MASK_LNA_CURRENT_GAIN) {
+	case LNA_GAIN_AUTO_SHIFTED:	    return automatic;
+	case LNA_GAIN_MAX_SHIFTED:	    return max;
+	case LNA_GAIN_MAX_MINUS_6_SHIFTED:  return maxMinus6;
+	case LNA_GAIN_MAX_MINUS_12_SHIFTED: return maxMinus12;
+	case LNA_GAIN_MAX_MINUS_24_SHIFTED: return maxMinus24;
+	case LNA_GAIN_MAX_MINUS_36_SHIFTED: return maxMinus36;
+	case LNA_GAIN_MAX_MINUS_48_SHIFTED: return maxMinus48;
  	default:		    return undefined;
  	}
  }
diff --git a/drivers/staging/pi433/rf69_registers.h b/drivers/staging/pi433/rf69_registers.h
index d23b8b668ef5..6329bbf9e499 100644
--- a/drivers/staging/pi433/rf69_registers.h
+++ b/drivers/staging/pi433/rf69_registers.h
@@ -237,6 +237,7 @@
  #define  MASK_LNA_ZIN				0x80
  #define  MASK_LNA_CURRENT_GAIN			0x38
  #define  MASK_LNA_GAIN				0x07
+#define  SHIFT_LNA_CURRENT_GAIN			3
#define LNA_GAIN_AUTO 0x00 /* default */
  #define  LNA_GAIN_MAX				0x01
@@ -246,6 +247,13 @@
  #define  LNA_GAIN_MAX_MINUS_36			0x05
  #define  LNA_GAIN_MAX_MINUS_48			0x06
+#define LNA_GAIN_AUTO_SHIFTED (LNA_GAIN_AUTO << SHIFT_LNA_CURRENT_GAIN)
+#define  LNA_GAIN_MAX_SHIFTED			(LNA_GAIN_MAX		<< SHIFT_LNA_CURRENT_GAIN)
+#define  LNA_GAIN_MAX_MINUS_6_SHIFTED		(LNA_GAIN_MAX_MINUS_6	<< SHIFT_LNA_CURRENT_GAIN)
+#define  LNA_GAIN_MAX_MINUS_12_SHIFTED		(LNA_GAIN_MAX_MINUS_12	<< SHIFT_LNA_CURRENT_GAIN)
+#define  LNA_GAIN_MAX_MINUS_24_SHIFTED		(LNA_GAIN_MAX_MINUS_24	<< SHIFT_LNA_CURRENT_GAIN)
+#define  LNA_GAIN_MAX_MINUS_36_SHIFTED		(LNA_GAIN_MAX_MINUS_36	<< SHIFT_LNA_CURRENT_GAIN)
+#define  LNA_GAIN_MAX_MINUS_48_SHIFTED		(LNA_GAIN_MAX_MINUS_48	<< SHIFT_LNA_CURRENT_GAIN)
/* RegRxBw (0x19) and RegAfcBw (0x1A) */
  #define  MASK_BW_DCC_FREQ			0xE0


Hi Valentin,

nice :-)

Name is a bit strange, since it's not really shifted. If you have a look at the datasheet (RegLNA, page 68), there are two sections "by chance" both using the max, -6, -12 ... But auto is not needed for current gain (was already bad in my old implementation!), since the current gain will always report a real value, never auto. So maybe it is a little(!) better not to derive the "current" defines from the "select" defines and use names like LNA_GAIN_MAX_SELECT and LNA_GAIN_MAX_CURRENT.

Never the less - I like patch 6/8 v2 a lot more, than the original one :-)

Thank you very much for your help,

Marcus

_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel



[Index of Archives]     [Linux Driver Backports]     [DMA Engine]     [Linux GPIO]     [Linux SPI]     [Video for Linux]     [Linux USB Devel]     [Linux Coverity]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [Yosemite Backpacking]
  Powered by Linux