summaryrefslogtreecommitdiffstats
path: root/drivers/mtd/nand/gpio.c
diff options
context:
space:
mode:
authorChristophe Leroy <christophe.leroy@c-s.fr>2017-02-10 15:01:10 +0100
committerBoris Brezillon <boris.brezillon@free-electrons.com>2017-03-16 10:34:27 +0100
commit44dd182861f99f04171256f29b9dc51940757e5d (patch)
treeb63db2eb4070eb0016667ad3779345c49fab3410 /drivers/mtd/nand/gpio.c
parentmtd: nand: Update dependency of IFC for LS1021A (diff)
downloadlinux-44dd182861f99f04171256f29b9dc51940757e5d.tar.xz
linux-44dd182861f99f04171256f29b9dc51940757e5d.zip
mtd: nand: gpio: make nCE GPIO optional
On some hardware, the nCE signal is wired to the ChipSelect associated to bus address of the NAND, so it is automatically driven during the memory access and it is not managed by a GPIO. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Marek Vasut <marek.vasut@gmail.com> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Diffstat (limited to 'drivers/mtd/nand/gpio.c')
-rw-r--r--drivers/mtd/nand/gpio.c18
1 files changed, 12 insertions, 6 deletions
diff --git a/drivers/mtd/nand/gpio.c b/drivers/mtd/nand/gpio.c
index 0d24857469ab..85294f150f4f 100644
--- a/drivers/mtd/nand/gpio.c
+++ b/drivers/mtd/nand/gpio.c
@@ -78,7 +78,9 @@ static void gpio_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
gpio_nand_dosync(gpiomtd);
if (ctrl & NAND_CTRL_CHANGE) {
- gpio_set_value(gpiomtd->plat.gpio_nce, !(ctrl & NAND_NCE));
+ if (gpio_is_valid(gpiomtd->plat.gpio_nce))
+ gpio_set_value(gpiomtd->plat.gpio_nce,
+ !(ctrl & NAND_NCE));
gpio_set_value(gpiomtd->plat.gpio_cle, !!(ctrl & NAND_CLE));
gpio_set_value(gpiomtd->plat.gpio_ale, !!(ctrl & NAND_ALE));
gpio_nand_dosync(gpiomtd);
@@ -201,7 +203,8 @@ static int gpio_nand_remove(struct platform_device *pdev)
if (gpio_is_valid(gpiomtd->plat.gpio_nwp))
gpio_set_value(gpiomtd->plat.gpio_nwp, 0);
- gpio_set_value(gpiomtd->plat.gpio_nce, 1);
+ if (gpio_is_valid(gpiomtd->plat.gpio_nce))
+ gpio_set_value(gpiomtd->plat.gpio_nce, 1);
return 0;
}
@@ -239,10 +242,13 @@ static int gpio_nand_probe(struct platform_device *pdev)
if (ret)
return ret;
- ret = devm_gpio_request(&pdev->dev, gpiomtd->plat.gpio_nce, "NAND NCE");
- if (ret)
- return ret;
- gpio_direction_output(gpiomtd->plat.gpio_nce, 1);
+ if (gpio_is_valid(gpiomtd->plat.gpio_nce)) {
+ ret = devm_gpio_request(&pdev->dev, gpiomtd->plat.gpio_nce,
+ "NAND NCE");
+ if (ret)
+ return ret;
+ gpio_direction_output(gpiomtd->plat.gpio_nce, 1);
+ }
if (gpio_is_valid(gpiomtd->plat.gpio_nwp)) {
ret = devm_gpio_request(&pdev->dev, gpiomtd->plat.gpio_nwp,