linux-kernel - [PATCH] mfd: lpc_ich: Do not touch SPI-NOR write protection bit on Apollo Lake

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Date:   Thu,  4 Jan 2018 12:20:18 +0300
From:   Mika Westerberg <mika.westerberg@...ux.intel.com>
To:     Lee Jones <lee.jones@...aro.org>, Peter Tyser <ptyser@...-inc.com>
Cc:     Mika Westerberg <mika.westerberg@...ux.intel.com>,
        linux-kernel@...r.kernel.org
Subject: [PATCH] mfd: lpc_ich: Do not touch SPI-NOR write protection bit on Apollo Lake

Just to be on the safe side, don't touch the bit. If write access to the
flash chip is needed, the BIOS needs to enable it explicitly.

Signed-off-by: Mika Westerberg <mika.westerberg@...ux.intel.com>
---
 drivers/mfd/lpc_ich.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/drivers/mfd/lpc_ich.c b/drivers/mfd/lpc_ich.c
index cf1120abbf52..53dc1a43472c 100644
--- a/drivers/mfd/lpc_ich.c
+++ b/drivers/mfd/lpc_ich.c
@@ -1143,11 +1143,6 @@ static int lpc_ich_init_spi(struct pci_dev *dev)
 			res->end = res->start + SPIBASE_APL_SZ - 1;
 
 			pci_bus_read_config_dword(bus, spi, BCR, &bcr);
-			if (!(bcr & BCR_WPD)) {
-				bcr |= BCR_WPD;
-				pci_bus_write_config_dword(bus, spi, BCR, bcr);
-				pci_bus_read_config_dword(bus, spi, BCR, &bcr);
-			}
 			info->writeable = !!(bcr & BCR_WPD);
 		}
 
-- 
2.15.1