[PATCH v8 11/15] mtd: spi-nor-core: Add the ->ready() hook

[tkuw584924]

From: Takahiro Kuwano <takahiro.kuw...@infineon.com>

For dual/quad die package devices from Spansion/Cypress, the device's
status needs to be checked by reading status registers in all dies, by
using Read Any Register command. To support this, a Flash specific hook
that can overwrite the legacy status check is needed.

Signed-off-by: Takahiro Kuwano <takahiro.kuw...@infineon.com>
Reviewed-by: Pratyush Yadav <p.ya...@ti.com>
---
Changes in v8:
  - No change
  
Changes in v7:
  - No change
  
Changes in v6:
  - Rebase and fix commit description
  
Changes in v5:
  - Move spansion_sr_ready() to different patch
  - Move original code in spi_nor_ready() to newly created
    spi_nor_default_ready()

 drivers/mtd/spi/spi-nor-core.c | 10 +++++++++-
 include/linux/mtd/spi-nor.h    |  2 ++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c
index ac8ebfc4f0..8a2c5d949a 100644
--- a/drivers/mtd/spi/spi-nor-core.c
+++ b/drivers/mtd/spi/spi-nor-core.c
@@ -567,7 +567,7 @@ static int spi_nor_fsr_ready(struct spi_nor *nor)
        return fsr & FSR_READY;
 }
 
-static int spi_nor_ready(struct spi_nor *nor)
+static int spi_nor_default_ready(struct spi_nor *nor)
 {
        int sr, fsr;
 
@@ -580,6 +580,14 @@ static int spi_nor_ready(struct spi_nor *nor)
        return sr && fsr;
 }
 
+static int spi_nor_ready(struct spi_nor *nor)
+{
+       if (nor->ready)
+               return nor->ready(nor);
+
+       return spi_nor_default_ready(nor);
+}
+
 /*
  * Service routine to read status register until ready, or timeout occurs.
  * Returns non-zero if error.
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index de4472da5c..2236e36e28 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -437,6 +437,7 @@ struct spi_flash {
  * @flash_is_locked:   [FLASH-SPECIFIC] check if a region of the SPI NOR is
  *                     completely locked
  * @quad_enable:       [FLASH-SPECIFIC] enables SPI NOR quad mode
+ * @ready:             [FLASH-SPECIFIC] check if the flash is ready
  * @priv:              the private data
  */
 struct spi_nor {
@@ -482,6 +483,7 @@ struct spi_nor {
        int (*flash_unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
        int (*flash_is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len);
        int (*quad_enable)(struct spi_nor *nor);
+       int (*ready)(struct spi_nor *nor);
 
        void *priv;
 /* Compatibility for spi_flash, remove once sf layer is merged with mtd */
-- 
2.25.1