[PATCH] staging: rtl8723bs: replace beacon timing magic numbers with named constants

[Jad Keskes <inasj268@gmail.com>]

Break down the 0x6404 and 0x660F in rtl8723b_InitBeaconParameters()
as requested by the TODO in the source.

REG_TBTT_PROHIBIT (0x0540): 0x6404 = hold (0x64) and setup (0x04),
both in 32us ticks.  Same layout as rtw88 (WLAN_TBTT_HOLD_TIME << 8 |
WLAN_TBTT_PROHIBIT in rtw88.h).

REG_BCNTCFG (0x0510): 0x660F is an EDCA-like register.  Lower byte is
AIFS (0x0F = no contention before beacon), next nibble is CWmin (0x06),
top nibble is CWmax (0x06).  Confirmed by rtl8192du/rtl8723ae in the
tree which write 0x66FF (test chips) and 0x660F (production) — only
AIFS varies, the CW byte stays 0x66.

The out-of-tree driver that Dan linked in the TODO discussion was the
reference for the bit assignments:
Link: https://lore.kernel.org/all/aiGMXBNQ0TbIGbpP@stanley.mountain/

Drop the TODO since this was the last thing it referenced.

Signed-off-by: Jad Keskes <inasj268@gmail.com>
Reviewed-by: Dan Carpenter <error27@gmail.com>
---
v2: Added Link: to Dan's TODO thread, expanded commit message per Greg's feedback
v3: Added in-tree references (rtw88, rtl8192du, rtl8723ae) and Dan's R-b tag

 drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c |  5 ++---
 drivers/staging/rtl8723bs/include/rtl8723b_hal.h  | 13 +++++++++++++
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c b/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c
index e794fe3caf9d..4afba1252161 100644
--- a/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c
+++ b/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c
@@ -878,8 +878,7 @@ void rtl8723b_InitBeaconParameters(struct adapter *padapter)
 
 	rtw_write16(padapter, REG_BCN_CTRL, val16);
 
-	/*  TODO: Remove these magic number */
-	rtw_write16(padapter, REG_TBTT_PROHIBIT, 0x6404);/*  ms */
+	rtw_write16(padapter, REG_TBTT_PROHIBIT, TBTT_PROHIBIT_TIME_8723B);
 	/*  Firmware will control REG_DRVERLYINT when power saving is enable, */
 	/*  so don't set this register on STA mode. */
 	if (check_fwstate(&padapter->mlmepriv, WIFI_STATION_STATE) == false)
@@ -888,7 +887,7 @@ void rtl8723b_InitBeaconParameters(struct adapter *padapter)
 
 	/*  Suggested by designer timchen. Change beacon AIFS to the largest number */
 	/*  because test chip does not contension before sending beacon. by tynli. 2009.11.03 */
-	rtw_write16(padapter, REG_BCNTCFG, 0x660F);
+	rtw_write16(padapter, REG_BCNTCFG, BCNTCFG_8723B);
 
 	pHalData->RegBcnCtrlVal = rtw_read8(padapter, REG_BCN_CTRL);
 	pHalData->RegTxPause = rtw_read8(padapter, REG_TXPAUSE);
diff --git a/drivers/staging/rtl8723bs/include/rtl8723b_hal.h b/drivers/staging/rtl8723bs/include/rtl8723b_hal.h
index ffd03927841c..81105c55afb2 100644
--- a/drivers/staging/rtl8723bs/include/rtl8723b_hal.h
+++ b/drivers/staging/rtl8723bs/include/rtl8723b_hal.h
@@ -72,6 +72,19 @@ struct rt_firmware_hdr {
 #define DRIVER_EARLY_INT_TIME_8723B  0x05
 #define BCN_DMA_ATIME_INT_TIME_8723B 0x02
 
+/* REG_TBTT_PROHIBIT (0x0540) - TBTT prohibit hold/setup in 32us units */
+#define TBTT_PROHIBIT_SETUP_8723B 0x04
+#define TBTT_PROHIBIT_HOLD_8723B  0x64
+#define TBTT_PROHIBIT_TIME_8723B \
+	((TBTT_PROHIBIT_HOLD_8723B << 8) | TBTT_PROHIBIT_SETUP_8723B)
+
+/* REG_BCNTCFG (0x0510) - beacon AIFS, CWmin, CWmax (EDCA-like layout) */
+#define BCN_AIFS_8723B   0x0F
+#define BCN_CW_MIN_8723B 0x06
+#define BCN_CW_MAX_8723B 0x06
+#define BCNTCFG_8723B \
+	((BCN_CW_MAX_8723B << 12) | (BCN_CW_MIN_8723B << 8) | BCN_AIFS_8723B)
+
 /* for 8723B */
 /* TX 32K, RX 16K, Page size 128B for TX, 8B for RX */
 #define PAGE_SIZE_TX_8723B 128
-- 
2.55.0