mtd: nand: omap2: Implement NAND ready using gpiolib

The GPMC WAIT pin status are now available over gpiolib.
Update the omap_dev_ready() function to use gpio instead of
directly accessing GPMC register space.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Tony Lindgren <tony@atomide.com>

1 files changed, 18 insertions, 11 deletions

diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
index 35b8f3359c17..e0b2b2f0fbde 100644
--- a/drivers/mtd/nand/omap2.c
+++ b/drivers/mtd/nand/omap2.c
@@ -12,6 +12,7 @@
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
 #include <linux/delay.h>
+#include <linux/gpio/consumer.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/jiffies.h>
@@ -182,6 +183,8 @@ struct omap_nand_info {
         struct nand_ecclayout           oobinfo;
         /* fields specific for BCHx_HW ECC scheme */
         struct device                   *elm_dev;
+        /* NAND ready gpio */
+        struct gpio_desc                *ready_gpiod;
 };
 
 static inline struct omap_nand_info *mtd_to_omap(struct mtd_info *mtd)
@@ -1023,21 +1026,16 @@ static int omap_wait(struct mtd_info *mtd, struct nand_chip *chip)
 }
 
 /**
- * omap_dev_ready - calls the platform specific dev_ready function
+ * omap_dev_ready - checks the NAND Ready GPIO line
  * @mtd: MTD device structure
+ *
+ * Returns true if ready and false if busy.
  */
 static int omap_dev_ready(struct mtd_info *mtd)
 {
-        unsigned int val = 0;
         struct omap_nand_info *info = mtd_to_omap(mtd);
 
-        val = readl(info->reg.gpmc_status);
-
-        if ((val & 0x100) == 0x100) {
-                return 1;
-        } else {
-                return 0;
-        }
+        return gpiod_get_value(info->ready_gpiod);
 }
 
 /**
@@ -1755,7 +1753,9 @@ static int omap_nand_probe(struct platform_device *pdev)
                 info->gpmc_cs = pdata->cs;
                 info->reg = pdata->reg;
                 info->ecc_opt = pdata->ecc_opt;
-                info->dev_ready = pdata->dev_ready;
+                if (pdata->dev_ready)
+                        dev_info(&pdev->dev, "pdata->dev_ready is deprecated\n");
+
                 info->xfer_type = pdata->xfer_type;
                 info->devsize = pdata->devsize;
                 info->elm_of_node = pdata->elm_of_node;
@@ -1787,6 +1787,13 @@ static int omap_nand_probe(struct platform_device *pdev)
         nand_chip->IO_ADDR_W = nand_chip->IO_ADDR_R;
         nand_chip->cmd_ctrl  = omap_hwcontrol;
 
+        info->ready_gpiod = devm_gpiod_get_optional(&pdev->dev, "rb",
+                                                    GPIOD_IN);
+        if (IS_ERR(info->ready_gpiod)) {
+                dev_err(dev, "failed to get ready gpio\n");
+                return PTR_ERR(info->ready_gpiod);
+        }
+
         /*
          * If RDY/BSY line is connected to OMAP then use the omap ready
          * function and the generic nand_wait function which reads the status
@@ -1794,7 +1801,7 @@ static int omap_nand_probe(struct platform_device *pdev)
          * chip delay which is slightly more than tR (AC Timing) of the NAND
          * device and read status register until you get a failure or success
          */
-        if (info->dev_ready) {
+        if (info->ready_gpiod) {
                 nand_chip->dev_ready = omap_dev_ready;
                 nand_chip->chip_delay = 0;
         } else {