From: Angus Clark <angus.clark@st.com>
Date: Wed, 26 Mar 2014 16:39:17 +0000 (+0000)
Subject: mtd: st_spi_fsm: Update Macronix 'QE' configuration
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=cc6668637ebed620eaafc807802f3d85b193f534;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git

mtd: st_spi_fsm: Update Macronix 'QE' configuration

Update the configuration of the Macronix 'QE' bit, such that
we only set or clear the bit if required.

Signed-off-by: Angus Clark <angus.clark@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
---

diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c
index 40eb830eea21..f86d3e01433b 100644
--- a/drivers/mtd/devices/st_spi_fsm.c
+++ b/drivers/mtd/devices/st_spi_fsm.c
@@ -1164,12 +1164,27 @@ static int stfsm_mx25_config(struct stfsm *fsm)
 					      CFG_ERASESEC_TOGGLE_32BIT_ADDR);
 	}
 
-	/* For QUAD mode, set 'QE' STATUS bit */
+	/* Check status of 'QE' bit */
+	stfsm_read_status(fsm, FLASH_CMD_RDSR, &sta);
 	data_pads = ((fsm->stfsm_seq_read.seq_cfg >> 16) & 0x3) + 1;
 	if (data_pads == 4) {
-		stfsm_read_status(fsm, FLASH_CMD_RDSR, &sta);
-		sta |= MX25_STATUS_QE;
-		stfsm_write_status(fsm, sta, 1);
+		if (!(sta & MX25_STATUS_QE)) {
+			/* Set 'QE' */
+			sta |= MX25_STATUS_QE;
+
+			stfsm_write_status(fsm, sta, 1);
+
+			stfsm_wait_busy(fsm);
+		}
+	} else {
+		if (sta & MX25_STATUS_QE) {
+			/* Clear 'QE' */
+			sta &= ~MX25_STATUS_QE;
+
+			stfsm_write_status(fsm, sta, 1);
+
+			stfsm_wait_busy(fsm);
+		}
 	}
 
 	return 0;