[MTD] Refactor NAND hwcontrol to cmd_ctrl

The hwcontrol function enforced a step by step state machine
for any kind of hardware chip access. Let the hardware driver
know which control bits are set and inform it about a change
of the control lines. Let the hardware driver write out the
command and address bytes directly. This gives a peformance
advantage for address bus controlled chips and simplifies the
quirks in the hardware drivers.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 8 insertions, 24 deletions

diff --git a/drivers/mtd/nand/cs553x_nand.c b/drivers/mtd/nand/cs553x_nand.c
index 064f3feadf53..cd3d7eb132f9 100644
--- a/drivers/mtd/nand/cs553x_nand.c
+++ b/drivers/mtd/nand/cs553x_nand.c
@@ -131,33 +131,17 @@ static void cs553x_write_byte(struct mtd_info *mtd, u_char byte)
         writeb(byte, this->IO_ADDR_W + 0x801);
 }
 
-static void cs553x_hwcontrol(struct mtd_info *mtd, int cmd)
+static void cs553x_hwcontrol(struct mtd_info *mtd, int cmd,
+                             unsigned int ctrl)
 {
         struct nand_chip *this = mtd->priv;
         void __iomem *mmio_base = this->IO_ADDR_R;
-        unsigned char ctl;
-
-        switch (cmd) {
-        case NAND_CTL_SETCLE:
-                ctl = CS_NAND_CTL_CLE;
-                break;
-
-        case NAND_CTL_CLRCLE:
-        case NAND_CTL_CLRALE:
-        case NAND_CTL_SETNCE:
-                ctl = 0;
-                break;
-
-        case NAND_CTL_SETALE:
-                ctl = CS_NAND_CTL_ALE;
-                break;
-
-        default:
-        case NAND_CTL_CLRNCE:
-                ctl = CS_NAND_CTL_CE;
-                break;
+        if (ctrl & NAND_CTRL_CHANGE) {
+                unsigned char ctl = (ctrl & ~NAND_CTRL_CHANGE ) ^ 0x01;
+                writeb(ctl, mmio_base + MM_NAND_CTL);
         }
-        writeb(ctl, mmio_base + MM_NAND_CTL);
+        if (cmd != NAND_CMD_NONE)
+                cs553x_write_byte(mtd, cmd);
 }
 
 static int cs553x_device_ready(struct mtd_info *mtd)
@@ -233,7 +217,7 @@ static int __init cs553x_init_one(int cs, int mmio, unsigned long adr)
                 goto out_mtd;
         }
 
-        this->hwcontrol = cs553x_hwcontrol;
+        this->cmd_ctrl = cs553x_hwcontrol;
         this->dev_ready = cs553x_device_ready;
         this->read_byte = cs553x_read_byte;
         this->write_byte = cs553x_write_byte;