mtd: m25p80: Create read_spi_reg and add read for flag status reg

Created read_spi_reg to perform atomic register read operation.
Added read_fsr and modified read_sr to call read_spi_reg.

Signed-off-by: Suneel Garapati <suneel.garapati@xilinx.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index dfda931fa47abfe0bdb8df999f12bc7dbd6199d5..2796193a644356a56937e56474c845ebb7424352 100644 (file)
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -47,6 +47,7 @@
 #define        OPCODE_CHIP_ERASE       0xc7    /* Erase whole flash chip */
 #define        OPCODE_SE               0xd8    /* Sector erase (usually 64KiB) */
 #define        OPCODE_RDID             0x9f    /* Read JEDEC ID */
+#define OPCODE_RDFSR           0x70    /* Read Flag Status Register */
 
 /* Used for SST flashes only. */
 #define        OPCODE_BP               0x02    /* Byte program */
@@ -70,6 +71,9 @@
 #define        SR_BP2                  0x10    /* Block protect 2 */
 #define        SR_SRWD                 0x80    /* SR write protect */
 
+/* Flag Status Register bits. */
+#define FSR_RDY                        0x80    /* Ready/Busy program erase
+                                       controller */
 /* Define max times to check status register before we give up. */
 #define        MAX_READY_WAIT_JIFFIES  (480 * HZ) /* N25Q specs 480s max chip erase */
 #define        MAX_CMD_SIZE            5
@@ -102,27 +106,45 @@ static inline struct m25p *mtd_to_m25p(struct mtd_info *mtd)
  */
 
 /*
- * Read the status register, returning its value in the location
- * Return the status register value.
+ * Read register, returning its value in the location
  * Returns negative if error occurred.
  */
-static int read_sr(struct m25p *flash)
+static inline int read_spi_reg(struct m25p *flash, u8 code, const char *name)
 {
        ssize_t retval;
-       u8 code = OPCODE_RDSR;
        u8 val;
 
        retval = spi_write_then_read(flash->spi, &code, 1, &val, 1);
 
        if (retval < 0) {
-               dev_err(&flash->spi->dev, "error %d reading SR\n",
-                               (int) retval);
+               dev_err(&flash->spi->dev, "error %d reading %s\n",
+                               (int) retval, name);
                return retval;
        }
 
        return val;
 }
 
+/*
+ * Read flag status register, returning its value in the location
+ * Return flag status register value.
+ * Returns negative if error occurred.
+ */
+static int read_fsr(struct m25p *flash)
+{
+       return read_spi_reg(flash, OPCODE_RDFSR, "FSR");
+}
+
+/*
+ * Read the status register, returning its value in the location
+ * Return the status register value.
+ * Returns negative if error occurred.
+ */
+static int read_sr(struct m25p *flash)
+{
+       return read_spi_reg(flash, OPCODE_RDSR, "SR");
+}
+
 /*
  * Write status register 1 byte
  * Returns negative if error occurred.