[v8,02/10] serial: sc16is7xx: mark IOCONTROL register as volatile

Message ID 20230607140525.833982-3-hugo@hugovil.com
State New
Headers
Series serial: sc16is7xx: fix GPIO regression and rs485 improvements |

Commit Message

Hugo Villeneuve June 7, 2023, 2:05 p.m. UTC
  From: Hugo Villeneuve <hvilleneuve@dimonoff.com>

Bit SRESET (3) is cleared when a reset operation is completed. Having
the IOCONTROL register as non-volatile will always read SRESET as 1,
which is incorrect.

Also, if IOCONTROL register is not a volatile register, the upcoming
patch "serial: sc16is7xx: fix regression with GPIO configuration"
doesn't work when setting some shared GPIO lines as modem control
lines.

Therefore mark IOCONTROL register as a volatile register.

Cc: <stable@vger.kernel.org> # 6.1.x
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: Lech Perczak <lech.perczak@camlingroup.com>
Tested-by: Lech Perczak <lech.perczak@camlingroup.com>
---
 drivers/tty/serial/sc16is7xx.c | 1 +
 1 file changed, 1 insertion(+)
  

Patch

diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index faa51a58671f..0c903d44429c 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -488,6 +488,7 @@  static bool sc16is7xx_regmap_volatile(struct device *dev, unsigned int reg)
 	case SC16IS7XX_TXLVL_REG:
 	case SC16IS7XX_RXLVL_REG:
 	case SC16IS7XX_IOSTATE_REG:
+	case SC16IS7XX_IOCONTROL_REG:
 		return true;
 	default:
 		break;