mtd: rawnand: stm32_fmc2: add NAND Write Protect support

This patch adds the support of the WP# signal. WP will be disabled
before the first access to the NAND flash.

Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>

diff --git a/drivers/mtd/nand/raw/stm32_fmc2_nand.c b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
index eee6594..fb3279b 100644 (file)
--- a/drivers/mtd/nand/raw/stm32_fmc2_nand.c
+++ b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
@@ -12,6 +12,7 @@
 #include <log.h>
 #include <nand.h>
 #include <reset.h>
+#include <asm/gpio.h>
 #include <dm/device_compat.h>
 #include <linux/bitfield.h>
 #include <linux/bitops.h>
@@ -149,6 +150,7 @@ struct stm32_fmc2_timings {
 struct stm32_fmc2_nand {
        struct nand_chip chip;
        struct stm32_fmc2_timings timings;
+       struct gpio_desc wp_gpio;
        int ncs;
        int cs_used[FMC2_MAX_CE];
 };
@@ -824,6 +826,9 @@ static int stm32_fmc2_nfc_parse_child(struct stm32_fmc2_nfc *nfc, ofnode node)
                nand->cs_used[i] = cs[i];
        }
 
+       gpio_request_by_name_nodev(node, "wp-gpios", 0, &nand->wp_gpio,
+                                  GPIOD_IS_OUT | GPIOD_IS_OUT_ACTIVE);
+
        nand->chip.flash_node = node;
 
        return 0;
@@ -972,6 +977,10 @@ static int stm32_fmc2_nfc_probe(struct udevice *dev)
        chip->ecc.size = FMC2_ECC_STEP_SIZE;
        chip->ecc.strength = FMC2_ECC_BCH8;
 
+       /* Disable Write Protect */
+       if (dm_gpio_is_valid(&nand->wp_gpio))
+               dm_gpio_set_value(&nand->wp_gpio, 0);
+
        ret = nand_scan_ident(mtd, nand->ncs, NULL);
        if (ret)
                return ret;