[PATCH v4 4/8] mtd: nand: xway: use generic reset function

[Hauke Mehrtens]

On 06/20/2016 10:50 AM, Boris Brezillon wrote:
> On Sun, 19 Jun 2016 19:03:01 +0200
> Hauke Mehrtens <hauke at hauke-m.de> wrote:
> 
>> Instead of writing an own reset function use the generic NAND reset
>> function. This way we can remove our own reset function.
>>
>> Signed-off-by: Hauke Mehrtens <hauke at hauke-m.de>
>> ---
>>  drivers/mtd/nand/xway_nand.c | 23 +++--------------------
>>  1 file changed, 3 insertions(+), 20 deletions(-)
>>
>> diff --git a/drivers/mtd/nand/xway_nand.c b/drivers/mtd/nand/xway_nand.c
>> index 6028edb..8a0019a 100644
>> --- a/drivers/mtd/nand/xway_nand.c
>> +++ b/drivers/mtd/nand/xway_nand.c
>> @@ -35,7 +35,6 @@
>>  #define NAND_CMD_CS		BIT(4) /* chip select */
>>  #define NAND_CMD_SE		BIT(5) /* spare area access latch */
>>  #define NAND_CMD_WP		BIT(6) /* write protect */
>> -#define NAND_WRITE_CMD_RESET	0xff
>>  #define NAND_WRITE_CMD		(NAND_CMD_CS | NAND_CMD_CLE)
>>  #define NAND_WRITE_ADDR		(NAND_CMD_CS | NAND_CMD_ALE)
>>  #define NAND_WRITE_DATA		(NAND_CMD_CS)
>> @@ -68,22 +67,6 @@ struct xway_nand_data {
>>  	struct nand_chip	chip;
>>  };
>>  
>> -static void xway_reset_chip(struct nand_chip *chip)
>> -{
>> -	unsigned long nandaddr = (unsigned long) chip->IO_ADDR_W;
>> -	unsigned long flags;
>> -
>> -	nandaddr &= ~NAND_WRITE_ADDR;
>> -	nandaddr |= NAND_WRITE_CMD;
>> -
>> -	/* finish with a reset */
>> -	spin_lock_irqsave(&ebu_lock, flags);
>> -	writeb(NAND_WRITE_CMD_RESET, (void __iomem *) nandaddr);
>> -	while ((ltq_ebu_r32(EBU_NAND_WAIT) & NAND_WAIT_WR_C) == 0)
>> -		;
>> -	spin_unlock_irqrestore(&ebu_lock, flags);
>> -}
>> -
>>  static void xway_select_chip(struct mtd_info *mtd, int chip)
>>  {
>>  
>> @@ -199,14 +182,14 @@ static int xway_nand_probe(struct platform_device *pdev)
>>  		| NAND_CON_SE_P | NAND_CON_WP_P | NAND_CON_PRE_P
>>  		| cs_flag, EBU_NAND_CON);
>>  
>> -	/* finish with a reset */
>> -	xway_reset_chip(&data->chip);
>> -
>>  	/* Scan to find existence of the device */
>>  	err = nand_scan(mtd, 1);
>>  	if (err)
>>  		return err;
>>  
>> +	/* finish with a reset */
>> +	data->chip.cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
>> +
> 
> Hm, I wonder if this is really useful. The NAND chip is already reset
> as part of the nand_scan() process. Are you sure you need to reset it
> again here?
> 
> Can you test after dropping this reset operation?
> 

Yes it looks like this is not needed at all, I will send new patches.

Hauke