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>

diff --git a/Documentation/devicetree/bindings/mtd/gpmc-nand.txt b/Documentation/devicetree/bindings/mtd/gpmc-nand.txt
index ff3215d..3ee7e20 100644 (file)
--- a/Documentation/devicetree/bindings/mtd/gpmc-nand.txt
+++ b/Documentation/devicetree/bindings/mtd/gpmc-nand.txt
@@ -48,6 +48,7 @@ Optional properties:
                locating ECC errors for BCHx algorithms. SoC devices which have
                ELM hardware engines should specify this device node in .dtsi
                Using ELM for ECC error correction frees some CPU cycles.
                locating ECC errors for BCHx algorithms. SoC devices which have
                ELM hardware engines should specify this device node in .dtsi
                Using ELM for ECC error correction frees some CPU cycles.

+ - rb-gpios:   GPIO specifier for the ready/busy# pin.

 
 For inline partition table parsing (optional):
 
 
 For inline partition table parsing (optional):
 


@@ -78,6 +79,7 @@ Example for an AM33xx board:
                        nand-bus-width = <16>;
                        ti,nand-ecc-opt = "bch8";
                        ti,nand-xfer-type = "polled";
                        nand-bus-width = <16>;
                        ti,nand-ecc-opt = "bch8";
                        ti,nand-xfer-type = "polled";

+                       rb-gpios = <&gpmc 0 GPIO_ACTIVE_HIGH>; /* gpmc_wait0 */

 
                        gpmc,sync-clk-ps = <0>;
                        gpmc,cs-on-ns = <0>;
 
                        gpmc,sync-clk-ps = <0>;
                        gpmc,cs-on-ns = <0>;

diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
index 35b8f33..e0b2b2f 100644 (file)
--- 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/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>
 #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;
        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)
 };
 
 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
  * @mtd: MTD device structure

+ *
+ * Returns true if ready and false if busy.

  */
 static int omap_dev_ready(struct mtd_info *mtd)
 {
  */
 static int omap_dev_ready(struct mtd_info *mtd)
 {

-       unsigned int val = 0;

        struct omap_nand_info *info = mtd_to_omap(mtd);
 
        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->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;
                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;
 
        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
        /*
         * 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
         */
         * 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 {
                nand_chip->dev_ready = omap_dev_ready;
                nand_chip->chip_delay = 0;
        } else {

diff --git a/include/linux/platform_data/mtd-nand-omap2.h b/include/linux/platform_data/mtd-nand-omap2.h
index 7f6de53..17d57a1 100644 (file)
--- a/include/linux/platform_data/mtd-nand-omap2.h
+++ b/include/linux/platform_data/mtd-nand-omap2.h
@@ -71,7 +71,6 @@ struct omap_nand_platform_data {
        int                     cs;
        struct mtd_partition    *parts;
        int                     nr_parts;
        int                     cs;
        struct mtd_partition    *parts;
        int                     nr_parts;

-       bool                    dev_ready;

        bool                    flash_bbt;
        enum nand_io            xfer_type;
        int                     devsize;
        bool                    flash_bbt;
        enum nand_io            xfer_type;
        int                     devsize;


@@ -82,5 +81,6 @@ struct omap_nand_platform_data {
        /* deprecated */
        struct gpmc_nand_regs   reg;
        struct device_node      *of_node;
        /* deprecated */
        struct gpmc_nand_regs   reg;
        struct device_node      *of_node;

+       bool                    dev_ready;

 };
 #endif
 };
 #endif