[PATCH 2/3] mtd: mtk-nor: mtk serial flash controller driver

Lothar Waßmann LW at KARO-electronics.de
Wed Sep 9 06:00:50 PDT 2015


Hi,

> > +	writeb(len, mt8173_nor->base + MTK_NOR_CNT_REG);
> > +	return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PRG_CMD);
> > +}
> > +
> > +static int mt8173_nor_get_para(struct mt8173_nor *mt8173_nor, u8 *buf, int len)
> > +{
> > +	if (len > 1) {
> > +		/* read JEDEC ID need 4 bytes commands */
> > +		mt8173_nor_set_cmd(mt8173_nor, 0, 32, SPINOR_OP_RDID);
> > +		buf[2] = readb(mt8173_nor->base + MTK_NOR_SHREG0_REG);
> > +		buf[1] = readb(mt8173_nor->base + MTK_NOR_SHREG1_REG);
> > +		buf[0] = readb(mt8173_nor->base + MTK_NOR_SHREG2_REG);
> > +	} else {
> > +		if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_RDSR_CMD)) {
> > +			dev_err(mt8173_nor->dev, "read status failed!\n");
> > +			return -EINVAL;
> > +		}
> > +		*buf = readb(mt8173_nor->base + MTK_NOR_RDSR_REG);
> > +	}
> > +	return 0;
> > +}
> > +
> > +/* cmd1 sent to nor flash, cmd2 write to nor controller */
> > +static int mt8173_nor_set_para(struct mt8173_nor *mt8173_nor, int cmd1,
> > +			       int cmd2)
> > +{
> > +	if (mt8173_nor_set_cmd(mt8173_nor, 0, 8, SPINOR_OP_WREN)) {
> > +		dev_err(mt8173_nor->dev,
> > +			"write enable failed in write protect!\n");
> > +		return -EINVAL;
> > +	}
> > +	writeb(cmd1, mt8173_nor->base + MTK_NOR_PRGDATA5_REG);
> > +	writeb(8, mt8173_nor->base + MTK_NOR_CNT_REG);
> > +	if (mt8173_nor_execute_cmd(mt8173_nor, cmd2)) {
> > +		dev_err(mt8173_nor->dev, "execute cmd failed!\n");
> 
> mt8173_nor_execute_cmd() will already have printed an error message.
> 
And mt8173_nor_execute_cmd()/mt8173_nor_set_cmd() returned an error
code which should be promoted to the caller rather than
inventing a new one.
The same for other instances of this code fragment.


Lothar Waßmann



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