mtd: rawnand: diskonchip: Replace mdelay with usleep_range in doc_probe

doc_probe() is never called in atomic context.

doc_probe() is only called by init_nanddoc(), which is only set as
a parameter of module_init().
This function is not called in atomic context.

Despite never getting called from atomic context, doc_probe()
calls mdelay() to busily wait.
This is not necessary and can be replaced with usleep_range() to
avoid busy waiting.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>

diff --git a/drivers/mtd/nand/raw/diskonchip.c b/drivers/mtd/nand/raw/diskonchip.c
index 86a258d..8d0fb2d 100644 (file)
--- a/drivers/mtd/nand/raw/diskonchip.c
+++ b/drivers/mtd/nand/raw/diskonchip.c
@@ -1481,12 +1481,12 @@ static int __init doc_probe(unsigned long physadr)
                WriteDOC(tmp, virtadr, Mplus_DOCControl);
                WriteDOC(~tmp, virtadr, Mplus_CtrlConfirm);
 
-               mdelay(1);
+               usleep_range(1000, 2000);
                /* Enable the Millennium Plus ASIC */
                tmp = DOC_MODE_NORMAL | DOC_MODE_MDWREN | DOC_MODE_RST_LAT | DOC_MODE_BDECT;
                WriteDOC(tmp, virtadr, Mplus_DOCControl);
                WriteDOC(~tmp, virtadr, Mplus_CtrlConfirm);
-               mdelay(1);
+               usleep_range(1000, 2000);
 
                ChipID = ReadDOC(virtadr, ChipID);